Mol Gen Genet, 1979 Sep, 175(2), 159 - 74 Physical characterisation of the "Rac prophage" in E . coli K12; Kaiser K et al.; We confirm the hypothesis of Low (1973) that many E . coli K12 strains contain a prophage (the Rac prophage) located a few minutes clockwise of the trp operon on the genetic map . We have used restriction endonucleases and 32P-labelled probes to construct a physical map of this prophage . Some E . coli K12 strains, including AB1157, have lost the entire prophage, apparently by a specific deletion . This is consistent with prophage excision by site-specific recombination . lambda reverse (lambda rev) phages (Zissler et al., 1971) are recombination proficient derivatives of phage lambda in which the phage recombination functions have been replaced by analogous functions (RecE) derived from the host chromosome (Gottesman et al., 1974; Gillen et al., 1977) . Our data support the origin of lambda rev plages by recombination between lambda and the Rac prophage following excision of the Rac prophage from the E . coli chromosome . Important experimental data are included in the Figure legends. Mol Gen Genet, 1979 Sep, 175(2), 151 - 7 Location and characterisation of a new replication origin in the E . coli K12 chromosome; Diaz R et al.; A segment of DNA located in the region of the E . coli K12 chromosome previously identified by the Rac phenotype can function as a self-replicating plasmid . Evidence is presented that this plasmid, the oriJ plasmid, contains the origin of replication of a defective prophage postulated to be located in this chromosomal region by Low (1973) . The plasmid can only be maintained in strains in which this postulated prophage has been deleted . In strains which possess the prophage selection for plasmid maintenance permits the isolation of clones containing new deletions which we postulate are the result of prophage excision. Gene, 1979 Sep, 7(1), 1 - 14 Preparation and characterization of large amounts of restriction fragments containing the E . coli lac control elements; Hardies SC et al.; Large quantities of pure DNA fragments (789, 203 and 95 bp in length) containing the Escherichia coli lac controlling elements (operator, promoter, CRP binding site) were prepared from appropriate recombinant plasmids . High pressure liquid chromatography on RPC-5 or preparative sucrose gradient centrifugation was used to fractionate the pVH51 vector from the inserts . The fragments had few, if any, nicks or depurinated sites, and the majority of the fragment ends were intact . Absorbance-temperature profiles on the fragments showed multiphasic transitions. Z Naturforsch {C}, 1979 Sep-Oct, 34(9-10), 742 - 6 Inhibition of E . coli L-Asparaginase by reaction with 2,3-butanedione . Chemical modification of arginine and histidine residues; Petz D et al.; The inactivation of E . coli asparaginase by 2,3-butanedione studied with L-asparagine and diazooxonorvaline as substrates obeys pseudo first order kinetics . Activity losses are linear with respect to arginine and histidine modification, with complete inactivation being correlated with alteration of one arginine and one histidine per subunit . The rate of inactivation of the enzyme was reduced in the presence of competitive inhibitors like L-2-amino-2-carboxyethane-sulfonamide . Under comparable conditions 1,2-cyclo hexanedione does not affect the activity of L-asparaginase. J Pharm Pharmacol, 1979 Sep, 31(9), 583 - 7 Haemodynamic effects of the carboxylic ionophore monensin when administered before and during shock induced by E . coli endotoxin; McCaig DJ et al.; The haemodynamic effects of the carboxylic ionophore monensin have been examined in cats anaesthetized with sodium pentobarbitone . Marked increases in left ventricular dP/dtmax (and dP/dt at fixed isovolumic pressures) and slight increases in cardiac output and stroke volume occurred, indicating increased myocardial contractility . Heart rate was unchanged but systemic arterial pressure was substantially increased . Satisfactory increases in contractility and arterial pressure were obtained when monensin was infused intravenously in a total dose of 0.25 mg kg-1 over 10 min . Larger doses, especially if rapidly injected, resulted in very marked increases in myocardial contractility leading eventually to cardiac failure . The haemodynamic effects of monensin were markedly reduced during shock induced by E . coli endotoxin and there was unfortunately no evidence to suggest that this extremely potent compound might be potentially beneficial in this form of profound cardiovascular shock. Nucleic Acids Res, 1979 Aug 24, 6(12), 3891 - 909 Polynucleotide-protein interactions in the translation system . Identification of proteins interacting with tRNA in the A- and P-sites of E . coli ribosomes; Abdurashidova GG et al.; Ultraviolet irradiation (lambda = 254 nm) of ternary complexes of E . coli 70 S ribosomes with poly(U) and either Phe-tRNAPhe (in the A-site) or NAcPhe-tRNAPhe (in the P-site) effectively induces covalent linking of tRNA with a limited number of ribosomal proteins . The data obtained indicate that in both sites tRNA is in contact with proteins of both 30 S and 50 S subunits (S5, S7, S9, S10, L2, L6 and L16 proteins in the A-site and S7, S9, S11, L2, L4, L7/L12 and L27 proteins in the P-site) . Similar sets of proteins are in contact with total aminoacyl-tRNA and N-acetylaminoacyl-tRNA . However, here no contacts of tRNA in the P-site with the S7 and L25/S17 proteins were revealed, whereas in the A-site total aminoacyl-tRNA contacts L7/L12 . Proteins S9, L2 and, probably, S7 and L7/L12 are common to both sites. Biokhimiia, 1979 Aug, 44(8), 1521 - 3 {Selective inhibition of ribosomal RNA synthesis by rifampicin in E . coli cells}; Kliachko EV et al.; Under partial inhibition of total RNA synthesis by rifampicin the formation of beta- and beta'-subunits of RNA polymerase is stimulated and the rRNA synthesis is selectively repressed . The differential rate of synthesis of the beta- and beta'-subunits increases from 1,15% up to 2,88% in the presence of 30 micrograms rifampicin per ml . Simultaneously the differential rate of rRNA synthesis decreases from 41% down to 10% . The degree of inhibition of rRNA synthesis by rifampicin depends on the cell growth rate. Biokhimiia, 1979 Aug, 44(8), 1512 - 20 {Phospholipids of E . coli and activity of alkaline phosphatase}; Nesmeianova MA et al.; The effects of liposomes prepared from the E . coli lipids on the activity of soluble alkaline phosphatase and on the complementation reaction between its subunits were studied . It was shown that the liposomes nonspecifically catalyze the dimerization of the enzyme subunits without changing the dimer activity . The effects of phospholipases A2 and C on the activity of membrane-bound alkaline phosphatase were studied . An interrelationship was found between the level of hydrolysis of membrane phosphatidyl glycerol (PG) by these enzymes and the changes in the activity of membrane-bound alkaline phosphatase . It was also shown that PG is less accessible to the effects of phospholipases in the cells with derepressed biosynthesis of alkaline phosphatase . It is assumed that the membrane PG interacts with the membrane-bound alkaline phosphatase during its translocation into the periplasm. Mol Gen Genet, 1979 Aug, 175(1), 77 - 87 Characterization of lambdapolA transducing phages; effective expression of the E . coli polA gene; Murray NE et al.; lambdapolA phages carrying the polA gene in either orientation were isolated and characterised by genetic tests and by assay of the polA gene product after infection of E . coli or induction of lysogens . Lytic infection gave consistently better amplification of DNA polymerase I than that obtained by induction of a lysogen . Optimal amplification of DNA polymerase I was not achieved from the PL promoter of cro-phages, but some advantages accrued when the polA gene was oriented for transcription from the PL promoter of a cro+ phage . lambdapolA phages in which the polA allele was from E . coli strain C600 provided better amplification than phages with the polA allele from E . coli ED8659 . Induction of a lambdapolA1 cI857 Qam Sam prophage gave levels of DNA polymerase I approaching 100 times that found in the non-lysogenic Pol+ host . Genetics studies with the lambdapolA phages confirmed the previously postulated orientation of the polA gene within the E . coli genome. Mol Gen Genet, 1979 Jul 24, 174(3), 281 - 6 Different specific activities of the monomeric and oligomeric forms of plasmid DNA in transformation of B . subtilis and E . coli; Mottes M et al.; (1) The low residual transforming activity in preparations of monomeric, supercoiled, circular (CCC) forms of the plasmids pC194 and pHV14 could be attributed to the presence in such isolates of a small number of contaminating multimeric molecules . (2) E . coli derived preparations of pHV14, as in vitro recombinant plasmid capable of replication in both E . coli and B . subtilis, contain oligomeric forms of plasmid DNA in addition to the prevalent monomeric CCC form . The specific transforming activity of pHV14 DNA for E . coli is independent of the degree of oligomerization, whereas in transformation of B . subtilis the specific activity of the purified monomeric CCC molecules is at least four orders of magnitude less than that of the unfractionated preparation . (3) Oligomerization of linearized pHV14 DNA by T4 ligase results in a substantial increase of specific transforming activity when assayed with B . subtilis and causes a decrease when used to transform E . coli. Mol Gen Genet, 1979 Jul 2, 174(1), 53 - 8 Assembly of ribosomal subunits affected in a ribosomal mutant of E . coli having an altered L22 protein; Pardo D et al.; In this article we describe some in vivo properties of a coldsensitive ribosomal mutant from Escherichia coli . The mutation affects the rplV gene which is the structural gene of ribosomal protein L22 . Our work shows that at 22 degrees C, the biosynthesis of both ribosomal subunits and the maturation processing of 15S and 23S ribosomal RNA are impaired . Integration of our results in a general model of in vivo ribosomal assembly in E . coli is presented. Biophys Chem, 1979 Jul, 10(1), 47 - 54 Comparison of van 't Hoff and calorimetrically determined enthalpies of binding of N-phosphonacetyl-L-aspartate to E . coli aspartate transcarbamylase; Hofmann GE et al.; A comparison has been made of the values obtained by direct calorimetric measurements and van 't Hoff analysis, under similar conditions, for the enthalpy of binding of the bisubstrate analog N-phosphonacetyl-L-aspartate (PALA) to E . coli aspartate transcarbamylase and its catalytic subunit . In the case of the catalytic subunit, data were obtained at both saturating and non-saturating concentrations of L-Asp, and at two ionic strengths . Despite a 1000-fold difference in protein concentrations, and the obligatory omission of carbamyl phosphate in the calorimetric experiments, the values obtained by the two methods are shown to agree to within 15% when appropriate corrections are made . These results suggest that subunit dissociation is not a significant factor at the low protein concentrations used in the van 't Hoff analysis, and, conversely, that aggregation of the protein is negligible at the high protein concentrations used in the calorimetric experiments . They also imply that, at pH 8.3, the enthalpic difference between the two conformational states of the enzyme which exist in the presence and absence of substrates is less than 2.5 kcal/mol . In addition, the trends in the three sets of data for the catalytic subunit indicate that ionic bonds are involved in binding PALA to the active site, and that non-productive binding by L-Asp is negligible under these experimental conditions. Vopr Med Khim, 1979 Jul-Aug, 25(4), 395 - 7 {Detection of plasmids in the cells of E . coli CK}; Nikol'skaia II et al.; Superspiralized coiled plasmide DNA were found in cells E . coli CK . One of plasmides pEco CK-1 had a size 21.2 micron that corresponded to molecular mass 43.7 megadaltons, another plasmide pEco CK-2 with the size 14.2 micron had a molecular weight 29.2 megadaltons . Effective restriction was observed in cross titration using phage PBV-I.CK for E . coli strains carrying R II plasmide and phage PBV-I.R II for E . coli CK cells . The data obtained suggest that the Eco CK type with DNA of host specificity is distinct from hsp II type due to presence of R II and N-15 plasmides. Antibiotiki, 1979 Jul, 24(7), 516 - 20 {Effect of low doses of chloramphenicol on ribosomal precursor formation in E . coli cells}; Drobyshev VI; RNA synthesized in the cells of E . coli CP 78 (rel+) in the presence of chloramphenicol low concentrations (5 microgram/ml) was found in 30S and 50S subunits and monosomes . A significant part of it was alotted to ribonucleoproteid or chloramphenicol particles . The protein content of ribonucleoproteid amounted to 22-25% and the content of RNA in it was equal to 78-75%. Dig Dis Sci, 1979 Jul, 24(7), 509 - 13 Differences in intrahepatic portal-systemic shunting in alcoholic and nonalcoholic liver disease as assessed by liver scan, portal pressure, and E . coli antibodies; Triger DR et al.; The interrelationship among portal vein pressure, 99mTc sulfur colloid liver/spleen scan abnormality, and serum E . coli antibody titers has been examined in 33 patients with alcoholic liver disease (ALD) and compared with 24 patients with liver disease not related to alcohol (non-ALD) . A correlation between portal vein pressure and liver scan abnormality is seen in both groups, but for a given degree of portal hypertension there is a much greater redistribution of sulfur colloid in the ALD group (P less than 0.01) . E . coli antibody titers are significantly higher in the ALD patients compared with the non-ALD patients (P less than 0.02), and they show a positive correlation with scan abnormality but not with portal vein pressure . It is suggested that the differences in scan appearance and E . coli antibody titers in these two groups of liver disease patients may be related to differences in intrahepatic shunting. Biokhimiia, 1979 Jul, 44(7), 1212 - 7 {Exogenous orthophosphate regulation of ATPase activity of E . coli cells}; Nesmeianova MA et al.; The effect of exogenous orthophosphate and mutations in genes, regulating the Pi transport system, on the ATPase activity of E . coli subcellular fractions was studied . It was shown that the orthophosphate starvation resulted in the cessation of the increase in the ATPase activity of membranes and was accompanied by the increase in the analogous activity of a soluble fraction at the expense of the derepression of alkaline phosphatase possessing this activity . The disturbance, resulted from the mutation of protein components participating in the specific binding and transport of orthophosphate, changed the ATPase activity of subcellular fractions: increased the ATPase activity of soluble fraction (independently of the presence of orthophosphate in medium), did not affect significantly the activity of membrane--bound ATPase in the presence of orthophosphate and decreased this activity in the absence of orthophosphate . The data obtained point to the fact that components, binding exogenous orthophosphate and transporting it into a cell, affect the rigidity of the ATPase bound E . coli cytoplasmic membrane . Mutations resulting in the defect in these components relax this bound and lead to the detection of ATPase proper in the periplasm. Biull Eksp Biol Med, 1979 Jul, 88(7), 65 - 8 {Dimethylaminochalcone, an indicator of the structural changes in the cellular envelop of E . coli under the action of Ca2+ cations and tris buffer}; Sabel'nikov AG et al.; An attempt was made to detect possible structural changes in E . coli cell envelope induced by Ca2+ treatment with the help of an uncharged fluorescent probe 4-dimethylaminochalcon (DMC) . The effects of the treatment with tris buffer (0.01 M) at 0 degrees C and other agents (Mg2+ and EDTA) were also studied for the purpose of comparison . It is shown that Ca2+ treatment of E . coli cells results in structural changes in the cell envelope surface, whick differ from those induced by tris-buffer at 0 degrees C, Mg2+ and EDTA . DMC can be used successfully as a suitable probe for monitoring structural changes in biomembranes. Nucleic Acids Res, 1979 Jun 25, 6(8), 2919 - 28 Blue dextran Sepharose chromatography of the tryptophanyl-tRNA synthetase of E . coli: a potential application for the purification of the enzyme; Drocourt JL et al.; E . coli tryptophanyl-tRNA synthetase can form a complex with Blue-dextran Sepharose, in the presence or in the absence of Mg++ . In its absence, the complex is dissociated by either ATP or cognate tRNATrp . However, in the presence of Mg++, only tRNATrp can dissociate the complex whereas ATP has no effect . E . coli total tRNA or tRNAMet, at the same concentration, cannot displace the synthetase from the complex . It is suggested that the Blue-dextran binds to the synthetase through its tRNA binding domain . This hypothesis is supported by previous findings with polynucleotide phosphorylase showing that Blue-dextran Sepharose can be used in affinity chromatography to recognize a polynucleotide binding site of the protein . The selective elution by its cognate tRNA of Trp-tRNA synthetase bound to Blue-dextran Sepharose provides a rapid and efficient purification of the enzyme . Examples of other synthetases and nucleotidyl transferases are also discussed. Nucleic Acids Res, 1979 Jun 11, 6(7), 2637 - 46 Studies on the RNA and protein binding sites of the E . coli ribosomal protein L10; Pettersson I; We have used modification of specific amino acid residues in the E . coli ribosomal protein L10 as a tool to study its interactions with another ribosomal protein, L7/L12, as well as with ribosomal core particles and with 23S RNA . The ribosome and RNA binding capability of L10 was found to be inhibited by modification of one more of its arginine residues . This treatment does not affect the ability of L10 to bind four molecules of L7/L12 in a L7/L12-L10 complex . Our results support the view that L10's role in promoting the L7/L12-ribosome association is due primarily to its ability to bind to both 23S RNA and L7/L12 simultaneously. Nucleic Acids Res, 1979 Jun 11, 6(7), 2545 - 60 A study on the unprimed poly (dA-dT) synthesis catalyzed by preparations of E . coli DNA polymerase I; Nazarenko IA et al.; Evidence was obtained indicating that the initiation of poly (dA-dT) de novo synthesis is provided by deoxynucleoside diphosphate: oligonucleotide deoxynucleotidyl transferase (dNDP-transferase present in preparations of E . coli DNA polymerase I and capable of catalyzing the unprimed polymerization of dNDP . dNDP-transferase synthesyzes short oligonucleotides which form template-primer complexes repeatedly replicated by DNA polymerase I . This conclusion was based on the following observations: the abolition of the lag period of poly (dA-dT) synthesis by preincubation of DNA-polymerase I preparations with dADP and dTDP; the presence of oligo (dA-dT) among the preincubation products; the suppressive effect of dithiothreitol and N-ethylmaleimide (inhibitors of dNDP-transferase) on the de novo, but not on the primed synthesis of poly (dA-dT), catalyzed by preparations of DNA-polymerase I. Mol Gen Genet, 1979 Jun 7, 173(2), 135 - 44 Synthesis and degradation of lac mRNA in E . coli depleted of 30S ribosomal subunits; Har-El R et al.; Escherichia coli was depleted of active ribosomes by a thermal shock at 47 degrees C which quantitatively destroyed the 30S ribosomal subunits . During recovery, RNA is synthesized while protein synthesis resumes only after about 90 minutes . It is shown that lac mRNA is synthesized in the complete absence of ribosomal activity and hence RNA synthesis is not coupled to protein synthesis . Transcription time and average transcript length were slightly less than in untreated cells . lac mRNA was degraded much more slowly in bacteria depleted of ribosomes . In E . coli W both functional half life (T 1/2 = 28 min vs . 2.25 in untreated cells) and chemical stability . The analysis of rna and pnp mutants showed that polynucleotide phosphorylase is involved in lac mRNA degradation in heat treated cells but that RNase I is not . The functional T 1/2 was increased in pnp mutants and was 95 min during the recovery period . The rate of chemical decay is so slow that the half-life cannot be accurately determined. Mol Gen Genet, 1979 Jun 7, 173(2), 127 - 34 Relief of polarity in E . coli depleted of 30S ribosomal subunits; Cohen T et al.; Escherichia coli was depleted of ribosomes by a thermal shock at 47 degrees C which quantitatively destroyed the 30S ribosomal subunits . During recovery in minimal medium at 30 degrees C RNA is synthesized while protein synthesis resumes only after about 90 min . It is shown that lac mRNA is synthesized in the complete absence of ribosomal activity and hence RNA synthesis is not coupled to protein synthesis . Lac mRNA from a series of lac nonsense mutants was examined in both heated and untreated cells . It was found that the polar effect of nonsense mutation is relieved in the absence of ribosomes and that this relief is due to the synthesis of larger mRNA molecules . Since Rho remained active in thermally treated cells, premature termination at secondary signals within the lac operon must also depend on the presence of active ribosomes. Rev Bras Pesqui Med Biol, 1979 Jun, 12(2-3), 117 - 22 Liquid holding recovery in E . coli K12 . I - Substances released during buffer holding; Aragao BR et al.; It is known that the incubation, in a buffer, of UV-irradiated E . coli cells results in viability increase, this phenomenon had been called liquid holding recovery (LHR) . We have studied the cellular constituents release during LHR and verified that releasing rate is dose-dependent . LHR was also observed after nitrogen-mustard treatment and it is not blocked by caffeine . So, we suggest that LHR expression is not always a rec-gene dependent function and, probably, the survival increase could be explained by (a) DNA-repair, (b) reversible membrane damage and (c) cellular multiplication. Rev Bras Pesqui Med Biol, 1979 Jun, 12(2-3), 111 - 6 Some repair effectiveness coefficients as indicators of E . coli UV-resistance; Pelico JV et al.; Mathematical studies of E . coli survival curves to UV (254 nm) lead to the definition of a photoresistance parameter - the "mean survival dose" (MSD) - to compare radiation resistances of genetically related bacterial strains . Based on this MSD-parameter some repair coefficients were proposed as indicators of the relative effectiveness with which every repair system recovers radiation lesions in cells . The theoretical values calculated for the proposed coefficients are in agreement with those which were obtained from experimental data presented in the literature. Int J Radiat Biol Relat Stud Phys Chem Med, 1979 Jun, 35(6), 539 - 48 Influence of unsaturated fatty acids, membrane fluidity and oxygenation on the survival of an E . coli fatty acid auxotroph following gamma-irradiation; Yatvin MB et al.; Escherichia coli K1060, a fatty acid auxotroph unable to either synthesize or degrade unsaturated fatty acids (uFAs), was used to study the effect of membrane fluidity on survival after exposure to ionizing radiation . Using this strain of E . coli, significant alterations in the fatty acid composition of the membrane have been produced and verified by gas chromatography . Linolenic, oleic, elaidic and palmitelaidic acids were the uFAs used . Survival above the transition temperature (Tt) (liquid crystal in equilibrium gel) was comparable for these fatty-acid-supplemented membranes after exposure to gamma-irradiation, whereas gamma-irradiation below Tt resulted ina significant decrease in survival . An oxygen enhancement effect was observed for each experimental condition employed. Br J Cancer, 1979 Jun, 39(6), 755 - 60 Radiosensitization of E . coli B/r by the cytotoxic agent procarbazine: a hypoxic cell sensitizer preferentially toxic to aerobic cells and easily oxidized; Roberts PB; Procarbazine has been shown to be a hypoxic cell sensitizer of moderate ability in E . coli B/r, with an achievable enhancement ratio of 1.4 at subtoxic concentrations . The drug appears to act in a manner similar to the expected with the electron-affinic radiosensitizers . However, procarbazine and the electron-affinic sensitizers differ in two important respects . Unlike the electron-affinic sensitizers, procarbazine is not easily reduced, but is easily oxidized . It is more toxic to aerobic than to hypoxic cells . At the drug dosages in present clinical use, procarbazine is likely to be only a weak radiosensitizer . The possible implications of the data for the further development of a new class of sensitizers and combination therapy are discussed. Cell, 1979 Jun, 17(2), 265 - 74 E . coli DNA binding protein HU forms nucleosomelike structure with circular double-stranded DNA; Rouviere-Yaniv J et al.; The incubation of the E coli DNA binding protein HU with relaxed circular SV40 DNA in the presence of pure nicking-closing enzyme introduces up to 18 negative superhelical turns in the DNA molecules as measured by agarose gel electrophoresis . The maximal density of supercoiling is obtained at a HU-DNA mass ratio of 1 . Reconstituted DNA-HU complexes prefixed with glutaraldehyde appear as condensed circular structures having an average of 14 "beads" per circular SV40 DNA molecule, with a "bead" diameter of 180 +/- 23 A . The circular SV40 DNA is condensed by a ratio of 2.0-2.5 relative to naked DNA . This is similar to the ratio (2.4) measured for chromatin formed by reassociation of relaxed SV40 DNA with the four core histones. Biokhimiia, 1979 Jun, 44(6), 1101 - 9 {Transhydrogenase as an additional site of energy accumulation in the E . coli respiratory chain}; Chetkauskaite AV et al.; NAD+ reduction catalyzed by transhydrogenase (EC 1.6.1.1) from E . coli membrane particles at the expense of NADPH oxidation is coupled with phenyldicarbaundecaborate (PCB-) absorption by the particles . This process is inhibited by oxidative phosphorylation protonophorous uncouplers and by equilibration of concentrations of the substrates and products of the transhydrogenase reaction . Elimination of the water-soluble part of membrane ATPase results in the inhibition of PCB- absorption at the expense of the transhydrogenase reaction energy . Treatment of the particles by dicyclohexyl carbodiimide increases the transhydrogenase-coupled absorption of PCB- . The transhydrogenase-induced increase of pPCB in the suspension of particles is directly correlated with the ratio of ({NADPH}.{NAD+})/({NADP+}.{NADH}) . When this value is equal to 1, no energy-dependent increase of pPCB was observed . NADP+ reduction at the expense of NADH oxidation leads to a decrease in the amount of PCB- absorbed by the particles at the expense of ATP hydrolysis energy . The experimental data suggest that NADPH oxidation in the course of the transhydrogenase reaction is coupled with the formation of a membrane potential with a positive charge localized inside the particles. Mol Gen Genet, 1979 May 23, 173(1), 51 - 9 Inactivation of E . coli RNA polymerase by polyriboinosinic acid: heterogeneity of RS complexes; DeLorbe WJ et al.; Polyriboinosinic acid (poly I) inhibits initiation of transcription by binary complexes formed between Adenovirus 2 DNA and E . coli RNA polymerase holoenzyme . In the presence of poly I, just as in the presence of rifampicin, initiation of transcription exhibits a sigmoidal dependence on the temperature at which the binary complexes are formed . This indicates that I (closed) complexes between Ad 2 DNA and RNA polymerase are rapidly inactivated by poly I, but that RS (open) complexes are relatively resistant . However, even among the RS complexes, at least two classes can be distinguished on the basis of the degree to which they are resistant to poly I: RS-1 complexes are somewhat sensitive to poly I (half-time of inactivation approximately 10 min) while RS-2 complexes are almost completely resistant to the inhibitor (half-time of inactivation approximately 10 h) . For both types of RS complex, the degree of sensitivity to poly I is ionic strength-dependent. Mol Gen Genet, 1979 May 4, 172(2), 171 - 8 Isolation and restriction mapping of plasmids containing ribosomal DNA sequences from the rrn B cistron of E . coli; Palmer ML et al.; Recombinant plasmids containing the entire 16S RNA gene from the rrn B cistron of E . coli inserted in Col E1 and pBR322 plasmid vectors have been constructed . These plasmids have been mapped using several restriction endonucleases as well as by DNA-RNA hybridization . These maps reveal previously undetected restriction sites in the rrn B cistron and in Col E1 plasmid DNA. Mutat Res, 1979 May, 60(3), 263 - 70 Relative effectiveness of the 300--320 NM spectral region on sunlight for the production of primary lethal damage in E . coli cells; Harm W; Cell inactivation by sunlight exposure has been studied in E . coli CSR 603 (uvrA recA phr), a K12 derivative which is deficient in all known repair systems . Under suitable conditions, unfiltered sunlight inactivates these cells to 10(-3) survival within 30 sec . The effects of unfiltered sunlight have been compared with those of sunlight filtered through 1-cm layers of aqueous caffeine solutions ranging in concentration from 1 to 20 mg/ml . In the wavelength region of solar emission below 320 nm, which is most critical for DNA damage, the transmission of these liquid filters changes from 10 to 90% within 8-nm intervals . Thus our results permit minimum estimates for the fraction of lethal lesions produced by the solar spectrum below certain wavelenghts . In an experiment analyzed in this manner more than 80% of primary lethal lesions are caused by wavelengths less than 321 nm, and more than 50% by wavelengths less than 306 nm, while the contribution of wavelengths greater than 380 nm to primary lethal damage is below 1%. Biophys Chem, 1979 May, 9(4), 405 - 12 Relaxation kinetics of E . coli ribosomes: evidence for the reaction of 30S . IF3 complex with 50S ribosomal subunits; Chaires JB et al.; Addition of initiation factor IF3 to solutions of E . coli ribosomes dramatically alters their behavior in pressure-jump relaxation kinetic experiments in which 90 degrees light-scattering is used to monitor the macromolecular reaction . The effect of IF3 on relaxation processes attributed to "tight" couples is strongly dependent on the Mg2+ concentration . At 2.5 mM Mg2+, addition of 1 molar equivalent of IF3 decreases the relaxation amplitude by a factor of 3 relative to ribosome solutions without IF3 . However, at 5.0 mM Mg2+, addition of 1 molar equivalent of IF3 produces a marked increase in the relaxation amplitude, by a factor of 2-8 fold relative to ribosomes in the absence of IF3 . IF3 has no effect on the relaxation process attributed to "loose" couples at 10 mM Mg2+ . While we are unable to propose a precise mechanism for IF3 action with the data on hand, our results require that the 30S . IF3 complex either reacts with the 50S subunit, forming a 70S . IF3 intermediate, or acts as a pool of reactive 30S subunit . Further kinetic evidence is required to distinguish between these possible pathways. Mol Biol (Mosk), 1979 May-Jun, 13(3), 681 - 9 {Role of RNA-polymerase in gene activity regulation of E . coli RNA-polymerase mutants with a pleiotropic effect . I . Physiological and biochemical studies}; Kamzolova SG et al.; Four Rifr-mutants of E . coli B/r (rpo B401, rpo B402, rpo B403, rpo B409) which differ from the wild strain in one or more phenotypic properties besides rifampicin resistance were obtained . Transfer of the mutant Rifr-alleles into the parent strain gives the latter all the properties of the mutant . This indicates that the new properties are due to the pleiotropic effect of Rifr-mutations . Biochemical studies of the properties of RNA-polymerases from the mutants and the parent showed that some new properties of the mutants could not be explained by the appearance of analogous properties in the mutant RNA-polymerase itself . They seem to be caused by alteration in functional activity of the mutant enzyme, particulary, alteration of its control properties during transcription . The function of the beta-subunit in genetic transcription is discussed. Cell, 1979 May, 17(1), 211 - 24 Identification of initiation sites for the in vitro transcription of rRNA operons rrnE and rrnA in E . coli; Gilbert SF et al.; The transcription initiation sites of E . coli rRNA operons were determined using various DNA fragments derived from transducing phage lambda metA20 carrying rrnE and from hybrid plasmid pLC19-3 carrying rrnA . In vitro transcription products were analyzed for their 5' end sequences and their oligonucleotide compositions . The results are in full agreement with the nuceotide sequences of the DNA templates described in an accompanying paper (de Boer, Gilbert and Nomura, 1979) and allow us to make the following conclusions . First, there are two transcription, start sites on each of the rRNA operons; they are 109 bp apart in the case of rrnE and 117 +/- 1 bp aprart in rrnA . Second, the first start site is 283 bp upstream from the m16S rRNA coding region in the case of rrnE, while is 291 bp upstream in rrnA . Initiation starts with ATP in both cases . Finally, the second start sites are 174 and 174 +/- 1 bp from the m16S rRNA genes in rrnE and rrnA, respectively . Initiation starts with CTP in both cases . We have also shown that in the present in vitro transcription system, guanosine tetraphosphate (ppGpp) inhibits the synthesis of full-sized RNAs from both start sites in each rRNA operon. Cell, 1979 May, 17(1), 201 - 9 DNA sequences of promoter regions for rRNA operons rrnE and rrnA in E . coli; de Boer HA et al.; The nucleotide sequences have been determined for the promoter regions of two ribosomal RNA operons, rrnA and rrnE, in E . coli . The sequences cover the two in vitro transcription start sites identified for each operon (Gilbert, der Boer and Nomura, 1979) . The first two start sites are 283 and 291 bp preceding the mature 16S rRNA (m16S rNA) coding regions for rrnE and rrnA, respectively; the second start sites are 174 and 174 +/- 1 bp preceding the m16S rRNA coding regions for rrnE and rrnA, respectively . Each of these start sites has an identifiable "Pribnow box" sequence 6-7 bp upstream from the start site . The nucleotide sequences of the two operons have nearly complete homology from the m16S rRNA coding regions to positions 145 bp upstream from those regions, and at the regions surrounding the Pribnow boxes preceding the first start sites . The DNA sequences indicate that the RNAs transcribed from the first start sites of rrnE and rrnA are quite different in their first 150 nucleotides . These heterogeneous regions, however, precede the RNAse III cleavage sites (deduced previously by Young and Steitz, 1978), and the "precursor 16S rRNA" molecules are largely homogeneous . The nucleotide sequences of the promoter regions of the two rRNA operons are also compared with those or rrnD and rrnX, determined by Young and Steitz (1979), and some common features are discussed. Cell, 1979 May, 17(1), 175 - 84 Site-specific cleavage of DNA by E . coli DNA gyrase; Morrison A et al.; E . coli DNA gyrase, which catalyzes the supercoiling of DNA, cleaves DNA site-specifically when oxolinic acid and sodium dodecylsulfate are added to the reaction . We studied the structure of the gyrasecleaved DNA because of its implications for the reaction mechanism and biological role of gyrase . Gyrase made a staggered cut, creating DNA termini with a free 3' hydroxyl and a 5' extension that provided a template primer for DNA polymerase . The cleaved DNA was resistant to labeling with T4 polynucleotide kinase even after treatment with proteinase K . Thus the denatured enzyme that remains attached to cleaved DNA is covalently bonded to both 5' terminal extensions . The 5' extensions of many gyrase cleavage fragments from phi X174, SV40 and Col E1 DNA were partially sequenced using repair with E . coli DNA polymerase I . No unique sequence existed within the cohesive ends, but G was the predominant first base incorporated by DNA polymerase I . The cohesive and sequences of four gyrase sites were determined, and they demonstrated a four base 5' extension . The dinucleotide TG, straddling the gyrase cut on one DNA strand, provided the only common bases within a 100 bp region surrounding the cleavage sites . Analysis of other cleavage fragments showed that cutting between a TG doublet is common to most, or all, gyrase cleavages . Other bases common to some of the sequenced sites were clustered nonrandomly around the TG doublet, and may be variable components of the cleavage sequence . This diverse recognition sequence with common elements is a pattern shared with several other specific nucleic acid-protein interactions. Biull Eksp Biol Med, 1979 May, 87(5), 466 - 8 {Effect of formaldehyde and its aminomethylol derivatives on E . coli strains with various defects of the DNA repair systems}; Mitsevich EV et al.; It was shown that aminomethylol compounds formed during reaction of formaldehyde with amino acids and formaldehyde as well exert a pronounced lethal action on E . coli strains with various defects of the DNA repair systems . The correlation between the extent of the DNA depurination caused by in vitro action of diverse aminomethylol derivatives and the inactivation of bacteria by these derivatives is revealed . The data obtained suggest that the inactivating effect of formaldehyde and its aminomethylol derivatives seems likely to be due to the formation of depurinized groups in bacterial DNA rather than to dimerization of purine bases. Cell, 1979 May, 17(1), 225 - 34 Tandem promoters direct E . coli ribosomal RNA synthesis; Young RA et al.; To determine the special feature of ribosomal RNA promoters that might account for the highly efficient and regulated synthesis of rRNA in E . coli, we have analyzed the beginnings of two ribosomal RNA operons, rrnD and rrnX . DNA sequences for 425 bp preceding those specifying mature 16s rRNA are reported . In vitro transcription of restriction endonuclease fragments containing this region from either operon reveals the presence of two promoters about 110 nucleotides apart; they are denoted P1 and P2 . RNA synthesis from P1 is initiated with GTP at position -284 (relative to 16s sequences) in rrnD and with ATP at position -285 in rrnX . At P2, the RNA starts with CTP primarily at position-176 in both operons . The DNA sequences of the two operons are identical for 231 bp preceding the 16s rDNA (including a substantial region around P2); they then diverge almost completely, except for a notable 18 bp homology just preceding the transcription start site for P1 . Certain sequences implicated in the recognition of promoters by E . coli RNA polymerase are clearly identifiable in both P1 and P2; other features include an extended region preceding P1 which is strikingly rich in AT base pairs . Possible mechansims by which these tandem promoters contribute to the high frequency of rRNA transcription and to the differential expression of the E . coli rrn operons are discussed. Zentralbl Bakteriol {Orig A}, 1979 Apr, 243(2-3), 197 - 206 {Enteritis due to Escherichia coli O142 K86 H34 in a ward of premature infants . With a discussion on the problem of pathogenicity of "enteropathogenic serogroups of E . coli" (author's transl)}; Bockemuhl J et al.; E . coli O142 K86 H34 has been isolated from stool specimens of five babies in a ward of premature infants . Diarrheal stools were observed in two of them; one infant temporarily failed to gain weight, and the other developed a temporary loss of weight . Smooth stools observed in the third baby as well as asymptomatic infections in two others did not affect their normal development . The outbreak lasted 15 days; the source of infection and the mode of transmission remained unknown . The pathogenesis and importance of human diarrheal disease caused by E . coli is reviewed . Enteritis of adults and children due to enteroinvasive (EIEC) and enterotoxigenic (ETEC) strains is described . The etiological role of so-called "enteropathogenic E . coli" (EPEC), rejected increasingly during the past decade, has been demonstrated again in recent studies . Routine search for EPEC is suggested in cases of infantile enteritis in hospitals and other institutions. Nucleic Acids Res, 1979 Apr, 6(4), 1631 - 8 The binding of tyrosinyl-5'-AMP to tyrosyl-tRNA synthetase (E.coli); Grosse F et al.; The binding between tyrosyl-tRNA synthetase (E.coli) and the alkylanalogue of the aminoacyladenylate, tyrosinyl-5'-AMP, has been investigated by fluorescence titrations and rapid mixing experiments . Tyrosyl-tRNA synthetase has two equivalent and independent binding sites for tyrosinyl-5'-AMP . The intrinsic binding constant is 4 x 10(7)M-1 . The binding sites for tRNATyr and tyrosinyl-5'-AMP are independent of each other, the anticooperative mode of tRNA binding being preserved in the presence of tyrosinyl-5-AMP. Acta Pathol Microbiol Scand {C}, 1979 Apr, 87C(2), 99 - 105 Uptake of non-opsonized E . coli by unstimulated mouse peritoneal macrophages; Rollag H; A method is described for the study of phagocytosis of 32P-labelled, non-opsonized, viable E . coli by mouse peritoneal macrophages . Factors influencing the uptake, such as medium, number of bacteria and time of phagocytosis, were standardized . The kinetics of the uptake were studied by visual counting of bacteria and by measuring the distribution of radioactive labelling . The uptake of 32P by the macrophages is well correlated to the number of bacteria phagocytized . The amount of phagocytosis depends on the bacterial density of the medium and the time of phagocytosis . When the medium contains more than 10(9) bacteria per ml, the maximum phagocytic capacity is reached after 90 minutes. Biull Eksp Biol Med, 1979 Apr, 87(4), 328 - 30 {Electron microscopic study of conjugative plasmids from serologically typed E . coli AP1}; Kaliuzhnaia AP et al.; The plasmid DNAs isolated from E . coli AP1 were studied by electron microscopy . Two plasmid DNA forms (FB1-1 and FB1--2) with the mol wt of 35.9 +/- 0.5 x x 10(6) and 51.5 +/- 0.6 x 10(6) daltons, respectively, were revealed. Mol Gen Genet, 1979 Mar 5, 170(3), 299 - 308 The structure of the DNA containing the E . coli tRNATry gene; Yarus M et al.; Using the pMB9 recombinant plasmid pMY3, which contains a functional gene for the tRNATry mutant Su+7, the EcoRI fragment containing the tRNATry gene is mapped and oriented with respect to the HindIII site in the tetracycline region of pMB9 . Complete HpaII and HaeIII maps of the EcoRI fragment are derived . The Su+7 tRNA gene is placed by hybridization to these fragments, and the tRNA gene is oriented by using the restriction sites for HinfI, TaqI, and HpaII in the tRNA gene itself . A tRNAAsp gene is shown to lie adjacent to tRNATry, and is also placed and oriented in the map . The RI fragment itself originates in a locus adjacent to, and transcribed in the same direction as, the ribosomal RNA genes of phi 80d3 . The implications of the structure of the cloned DNA for its previously measured regulatory and tRNA gene activities are discussed . In particular, the effect on the regulation of RNA synthesis is attributable to an E . coli DNA sequence, but cannot be due to the presence of a normal tRNA promoter on the plasmid. Mol Gen Genet, 1979 Mar 5, 170(3), 291 - 8 Isolation and properties of a plasmid which expresses the E . coli Su+7 amber suppressor tRNA gene; Yarus M; The gene of the amber suppressor tRNA derived from tRNATry, Su+7, has been inserted into a col E1-derived vehicle by selecting for its expression . Despite selection for a suppressor phenotype, and the plasmid's stable presence at ca . 180 copies cell during balanced growth, the level mature tRNA maintained by the gene is less than that of the normal haploid tRNATry locus in the bacterial chromosome . Transfer RNA genes, both the plasmid Su+7 gene and chromosomal tRNA's are expressed during inhibition of protein synthesis . During, e.g . chloramphenicol inhibition, Su-7 and Su+7 tRNA can be elevated similarly in the plasmid-containing cell; Su+7 reaches levels of molecules/cell which ordinarily characterize a major tRNA . The recombinant plasmid, but not the cloning vehicle alone, has a more general effect on tRNA levels; accumulation of tRNA from three chromosomal tRNA loci including tRNATry, continues during extensive isoleucine limitation . The plasmid therefore contains a locus which probably alters the relaxed-stringent circuit, whose effect is disseminated to at least 3 widely separated loci. Biokhimiia, 1979 Mar, 44(3), 570 - 2 {Modification of the alpha-subunit of phenylalanyl-tRNA synthetase from E . coli MRE-600 with N-chlorambucilyl-phenylalanyl-tRNA}; Lavrik OI et al.; L-Phenylalanyl-tRNA synthetase from E . coli MRE-600 (EC 6.1.1.20) was alkylated with N-chlorambucilyl-{14C} phenylalanyl-tRNA . After removal of the affinity reagent tRNA moiety bp alkaline hydrolysis of the ester bond between the N-chlorambucilyl-phenylalanyl residue and the 3'-end of tRNA, The enzyme was dissociated into subunits in the presence of SDS . Separation of the subunits was performed by SDS electrophoresis . The bulk of the radioactivity of the N-chlorambucilyl-{14C} phenylalanyl residue was found at the position of the alpha-subunit of the enzyme . The results obtained are consistent with a specific binding of the phenylalanyl-tRNA analog to the alpha-subunit of the enzyme followed by covalent binding of the N-chlorambucilyl-phenylalanyl moiety to the protein. Biokhimiia, 1979 Mar, 44(3), 440 - 52 {Isolation and properties of DNA-cytosine-methyltransferase EcoRII and E . coli K12}; Bogdarina IG et al.; The methods of isolation and partial purification of two DNA-cytosine-methylases (DC-methylases) EcoRII and E . coli K12 are described . After chromatography on phosphocellulose the enzymes were purified 100-fold, the yield being 30% . Further purification of the enzymes was performed by sedimentation in a sucrose concentration gradient . Both enzymes have native molecular weights of 50,000; DC-methylase from E . coli K12 may simultaneously occur in the forms with molecular weights of 70,000, 90,000 and 110,000 . Both DC-methylases modify identical nucleotide sequences of DNA, have equal numbers (90) of methylation sites in phage lambda DNA and provide in vitro a complete protection of phage lambda DNA against restriction endonuclease EcoRII . DC-methylases E . Coli K12 and EcoRII differ in their chromatographic behaviour on phosphocellulose and capacity to form compexes with the cell DNA-adenine-methylase. Cell, 1979 Mar, 16(3), 617 - 25 Mutants in transmission of chemotactic signals from two independent receptors of E . coli; Hazelbauer GL et al.; We have characterized chemotactic mutants of E . coli that appear to be defective in a common linkage of two independent receptors to the central chemotactic components . The mutants do not respond to gradients of ribose or galactose and thus are called trg (taxis to ribose and galactose), after Ordal and Adler (1974b) . These trg mutants are indistinguishable from their parent in tactic response to other attractants, swimming pattern, growth rates, and transport of ribose and galactose . The mutant cells contain the usual amounts of ribose and galactose receptors, and those proteins function normally in their other role, transport of their respective ligands . The mutations, generated by insertion of translocatable drug-resistance elements (transposons)8 are located near 31 min on the map of the E . coli chromosome, a locus far removed from the genes coding for the ribose and galactose receptors . Trg mutants do not resemble either specific receptor mutants or che mutants . The nature of the requirement for the trg product in the response to ribose and galactose is not defined, but evidence for interference of tactic signals from the ribose and galactose receptors (Strange and Koshland, 1976) supports the idea that the product functions directly in the transmission of tactic signals from the two receptors to the flagella. Cell, 1979 Mar, 16(3), 523 - 34 Structure and organization of the two tRNATyr gene clusters on the E . coli chromosome; Rossi JJ et al.; The structure and organization of the gene clusters coding for the two tyrosine-accepting tRNA species (tRNA1Tyr and tRNA2Tyr) on the E . coli chromosome have been determined . The mature structural sequences of the two tRNATyr genes, located on opposite sides of the E . coli chromosome, differ by only 2 bp, but sequences surrounding these portions of the genes are very different . The genes coding for tRNA1Tyr (tyrT) comprise two mature structural sequences separated by a 200 bp "intergenic spacer." It is known that in transducing phage, the region adjoining the CCA end of the second mature structural sequence comprises a 178 bp repeated sequence which contains an in vitro, rho-dependent transcriptional termination site . We find that these potentially genetically unstable repeated sequences are present in the E . coli chromosome with the same organization as that determined from transducing phage analyses . The gene that codes for tRNA2Tyr (tyrU) is present in a single copy and is tightly clustered with three other tRNA genes . One of these genes (to be called thrU) encodes a previously undescribed tRNA (to be called tRNA4Thr) . The organization of this cluster on the E . coli chromosome is tRNA4Thr--8 bp--tRNA2Tyr--115 bp--tRNA2Gly--6 bp--tRNA3Thr . The importance of correlating structural analyses derived from specialized transducing phage with those determined for the chromosome itself is demonstrated by results which show that out of four independently isolated tRNATyr transducing phage, two carrying the tRNA1Tyr genes {phi80psu3+,- (Cambridge) and phi80sus2psu3+ (Kyoto)} and two carrying the tRNA2Tyr gene (lambdarifd 18 and lambdah80dglyTsu+36), only the first phage from each group has the same gene organization as that found in the E . coli chromosome. Zentralbl Bakteriol {Orig A}, 1979 Mar, 243(1), 16 - 27 The lethal effect and the inhibition of colicin production by leucine on a phenylalanine requiring E . coli strain as a function of age and dilution of culture; Ben-Gurion R; The lethal effect caused by leucine on a phenylalanine requiring strain of Escherichia coli K-12 (7), was found to be strongly affected by the age of the culture . Early log cells were the least sensitive, while older cells became more sensitive to leucine . Another important factor affecting the sensitivity of this strain to leucine in liquid medium was the range of dilution of the culture . The age sensitive culture reacted to leucine only when its dilution was at a certain specific range . The sensitivity to leucine of a culture treated at the "right" age and at the proper dilution was proportional to the concentration of leucine . Colicine production was studied with cultures treated in various ways using a colicinogenic derivative of the leucine sensitive strain . It was found that leucine in a rather high concentration (2 mg/ml) prevented colicine production when given in the absence of phenylalanine, while phenylalanine at a very low dose (0.2 microgram/ml) could reverse this inhibition . The effect of leucine on colicine production, like lethality, operated only under certain conditions of culture dilution, but unlike lethality, was not very sensitive to the age of the culture . Tryptophane was found to resemble leucine in its effects on viability and on colicine production in liquid medium . Its effect was likewise reversed by a small amount of phenylalanine, and like leucine, tryptophane acted best only under very specific conditions of culture dilution. Nucleic Acids Res, 1979 Mar, 6(3), 1041 - 8 2'-Deoxy-2'-fluorouridine-5'-triphosphates: a possible substrate for E . coli RNA polymerase; Pinto D et al.; dUflTP was tested as substrate in the E . coli RNA polymerase system using poly(dAT) as template . dUflTP could replace UTP when Mn++ was utilized as divalent cation instead of Mg++ . The level of transcription with the fluoro analog was then 55% of that with UTP. Zh Mikrobiol Epidemiol Immunobiol, 1979 Mar, (3), 63 - 6 {Determination of the localization of the kcpA gene on the chromosome of E . coli O124 . I . Use of the type F' plasmids of varying length}; Lycheva TA et al.; The loss of virulence was observed in some of the transconjugates of E . coli O124 in the process of the transfer of the plasmids differing in length: F' 200 PS, F'x 573 and F'x 363, carrying the genes of the chromosome area lac--pur E . The genetic determinants contributing to the ability of E . coli O124 to produce keratoconjunctivitis seem to be localized near the lactose marker, and not near E as in Sh . flexneri . In E . coli O124 these genetic determinants are probably localized on both sides of the lactose operon. Nucleic Acids Res, 1979 Mar, 6(3), 1189 - 201 Apparent allosterism by avian myeloblastosis virus reverse transcriptase and E . coli DNA polymerase I; Darling TL et al.; A recent report (1) presented evidence for allosterism in reverse transcription by Mason-Pfizer monkey virus reverse transcriptase and by E . coli DNA polymerase I . Our experiments also demonstrate these apparent cooperative effects when synthesis is catalyzed by either avian myeloblastosis virus DNA polymerase, feline sarcoma virus DNA polymerase, or E . coli DNA polymerase I (large fragment) . We show that the apparent cooperativity depends on the use of oligo(dT)12-18 as primer . However, if the polymerase reaction products are isolated chromatographically, then the polymerases obey classical Michaelis-Menten kinetics with respect to substrate and enzyme concentrations . These results suggest that the cooperative effects are an acid precipitation artifact . The results are also consistent with the enzyme operating by a distributive mechanism with the oligo(dT)12-18 primer. Mol Cell Biochem, 1979 Feb 9, 23(3), 167 - 75 E . coli galactose-1-phosphate uridyl transferase: N-terminal and C-terminal sequences; Raychowdhury R et al.; A modified procedure for the purification of E . coli galactose-1-phosphate uridyl transferase (E.C . 2.7.6.12) was developed which reproducibly gives pure enzyme . The purified enzyme was shown to be a dimeric protein with a subunit molecular weight of 41,000 and its amino acid composition and content of free sulfhydryl groups were determined . The N-terminal and C-terminal amino acid sequences were found to be NH2-thr-gln-phe-asn-pro-val-asp and -ser(val leu)-ala-COOH respectively . This N-terminal sequence allowed the identification of the start of the transferase gene in the DNA sequence determined by GRINDLEY . Furthermore it appears to define a nine base intercistronic region between the epimerase and transferase genes. Nature, 1979 Feb 8, 277(5696), 453 - 6 The E . coli gene encoding heat stable toxin is a bacterial transposon flanked by inverted repeats of IS1; So M et al.; Restriction endonuclease subclones of the Escherichia coli gene encoding the heat stable (ST) toxin exhibit a stem and loop structure similar to those seen in many procaryotic transposons . An EcoRI DNA fragment encoding tetracycline (Tc) resistance but no transposition functions was spliced into the ST gene in one of these subclones . By monitoring Tcr, we were able to show that the ST gene transposes . Restriction and DNA sequence data strongly suggest that the ST transposon, Tn 1681, is flanked by inverted repeats of IS1. Biokhimiia, 1979 Feb, 44(2), 364 - 7 {Dependence of the rate of aspartate ammonia-lyase reaction catalyzed by free and immobilized cells of E . coli on temperature and preliminary thermal treatment}; Zueva NN et al.; The effects of temperature (45--55 degrees) and duration of thermal treatment on the L-aspartase activity of free and immobilized on polyacrylamide gel cells of E . coli, strain 85 were studied . It was found that preliminary thermal treatment of the cells at 50 degrees for 40--60 min is optimal for a high aspartase activity . Within the temperature interval of 20--55 degrees the temperature dependence of effective rate constants of L-aspartate synthesis obeys the Arrhenius equation, whereas the effective energy of activation is decreased from 12,6 to 3,6 kcal/mole, when the "activation" of the cells shows an increase. Mol Gen Genet, 1979 Feb 1, 169(3), 337 - 43 Genetic organization of the E . coli chromosome around the structural gene for initiation factor IF3 (infC); Springer M et al.; A set of lambda transducing phages carrying varying lengths of the E . coli chromosome around the structural gene for initiation factor IF3 (infC) was derived from lambda p2 which is known to carry, besides infC, the structural genes for the alpha subunit of phenylalanyl-tRNA synthetase (pheS), the beta subunit of phenylalanyl-tRNA synthetase (pheT) and the structural gene for threonyl-tRNA synthetase (thrS) . The E . coli coding content of these derived phages was analysed by genetic complementation of a set of mutants and by SDS-polyacrylamide gel analysis of the proteins synthesized in UV irradiated cells infected with these phages . The segregation pattern of the different genes among these derived phages indicates that the order of the genes is pheT - pheS - "P12" - (infC, thrS) where infC is probably between "P12" and thrS . "P12" is the structural gene of a 12,000 molecular weight unidentified protein. Mol Gen Genet, 1979 Feb 1, 169(3), 279 - 87 W-reactivation of phage lambda in recF, recL, uvrA, and uvrB mutants of E . coli K-12; Rothman RH et al.; W-reactivation is reduced by recF143 and recF144 mutations and is undetectable if a second mutation at either the uvrA or uvrB locus is combined with recF143 . The uvrA and uvrB mutations alone block W-reactivation partially . A recL152 mutation also partially blocks W-reactivation by itself . In combination with a uvrB5 mutation, recL125 blocks W-reactivation completely but in combination with recF143, significant residual W-reactivation ability remains . We suggest that the phenomenon of W-reactivation is the result of at least two modes or pathways . The observation that recF143 uvrB5 and recF143 uvrA6 strains permit normal levels of mutagenesis (Kato et al., 1977) but completely block all W-reactivation leads us to suggest further that the mechanism(s) of W-reactivation is at least partly different from that of UV mutagenesis. Surgery, 1979 Feb, 85(2), 212 - 8 Amino acid metabolism in dogs with E . coli bacteremic shock; Woolf LI et al.; In 10 fasting dogs receiving 10(9) viable E . coli bacteria per kilogram intravenously, mean systolic blood pressure decreased from 120.6 +/- 15.1 to 82.2 +/- 12.8 mm Hg . The association of hypoglycemia and increased arterial alanine and glycine with elevated plasma glucagon implied impaired gluconeogenesis . A rapid elevation of blood urea concentration, indicating increased ureagenesis, a fall of blood glucose, and an increase of net urea synthesis relative to that of glucose suggested that an increased proportion of the carbon residues derived from glucogenic amino acids is catabolized via pathways other than gluconeogenesis . In the bacteremic dogs the absolute net release from the leg of valine, isoleucine, and leucine and their net release relative to the net rate of proteolysis were decreased, suggesting increased oxidation of these amino acids in skeletal muscle . An increased net release of alanine relative to the net rate of protein catabolism in muscle was in agreement with this contention. Mol Gen Genet, 1979 Jan 16, 169(1), 35 - 40 In vitro replication of a DNA fragment containing the vicinity of the origin of E . coli DNA replication; Nusslein-Crystalla V et al.; The restriction nuclease cleavage pattern of E . coli DNA synthesized in vitro in the cellophane membrane system (Schaller et al., 1972) is similar to the one obtained after labelling E . coli in vivo . This is shown for exponentially growing cells and for cells synchronized by amino acid starvation followed by thymine starvation . In synchronized cells a piece of some 180 kilobase pairs is labelled containing oriC and neighbouring regions at 82 min on the genetic map of E . coli . A pulse label in vitro is incorporated into the same piece of DNA, but the center of this region, i.e . the EcoR1 fragment of 8.6 kbp length which contains the oriC region (Marsh and Worcel, 1977; v . Meyenburg et al., 1977; Yasuda and Hirota, 1977) is missing. Mol Gen Genet, 1979 Jan 11, 168(3), 341 - 4 The isolation and genetic characteristics of lambda transducing phages of the uvrA+ and uvrC+ genes of E . coli K12; Auerbach J et al.; Lambda transducing phages carrying the excision repair genes uvrA+ and uvrC+ were selected from a pool of lambda phages carrying EcoR1 fragments of E . coli DNA . These phages and also lambdauvrB+ (obtained from Gottesman) were used to make lysogens of excision-defective strains carrying uvrA-, uvrB- or uvrC- . Lambda uvrA+ was found to transduce strains carrying uvrA- but not those carrying uvrB- or uvrC-, to normal ultraviolet resistance . Similarly, lambdauvrB+ and lambdauvrC+ were found to complement only the corresponding uvr- allele . The lambda transducing phages were co-transduced with gal+ by P1 phage into lysogenic gal- recipients, and presumably were integrated at the normal prophage site. Mol Gen Genet, 1979 Jan 2, 167(3), 235 - 41 Close vicinity of IS1 integration sites in the leader sequence of the gal operon of E . coli; Kuhn S et al.; Four insertions of IS1 in the leader sequence of the gal operon of E . coli have been analysed . Two of them occur at the same position, but in opposite orientations . The other two are inserted one nucleotide to one side and four nucleotides to the other side, respectively . In each case, nine base pairs of the leader sequence of the gal operon are duplicated directly, and are found flanking the termini of IS1 at its junction with the gal operon . These repeated sequences differ from each other as expected from the different insertion sites. Circ Shock, 1979, 6(3), 235 - 44 Failure of exogenous ATP and creatine phosphate to modify the course of E coli endotoxin shock in the cat; McCaig DJ et al.; Exogenous adenosine triphosphate (ATP) (in combination with MgCl2) and also creatine phosphate (CrP), have been administered intravenously to endotoxin-shocked cats . Untreated shocked cats exhibited systemic hypotension during the first hour and again from four hours . Cardiac output fell progressively, and markedly elevated arterial lactate levels were evident within one hour of endotoxin administration . Treatment with ATP (10 mg/kg every 30 minutes) during shock led to rapid hemodynamic deterioration in all cats; most of the cats were dead before completion of dosing (at three hours) . Long-lasting systemic hypotension and bradycardia were associated with this ATP administration and marked hypoglycemia developed in the survivors . Neither ATP (62 mg/kg) administered before endotoxin, nor CrP (500 mg/kg; administered either prior to endotoxin, or one hour afterwards) significantly modified the hemodynamic or metabolic changes associated with endotoxin shock in this species . Neither ATP nor CrP increased survival (assessed at five hours) . Other workers have demonstrated improved survival from shock with ATP treatment . There may be species differences in the responsiveness to exogenous ATP or, alternatively, a difference in the role of high-energy phosphates in different types of shock. Adv Shock Res, 1979, 2, 233 - 44 Effects of methylprednisolone sodium succinate on clearance of live E coli from the peripheral blood of dogs; White GL et al.; Corticosteroids have been reported to potentiate infections, and yet recent clinical and experimental studies have documented their therapeutic effectiveness in both septic and endotoxin shock . This study was designed to determine if methylprednisolone sodium succinate (MP) affects the clearance of live E coli organisms from peripheral blood of dogs . The experimental group was pretreated with 30 mg/kg of MP, and controls received equal volumes of saline . Both control and MP-pretreated dogs significantly reduced the number of E coli in peripheral blood by almost two orders of magnitude; however, there was no significant difference in clearance of E coli organisms between the two groups . An initial leukopenia occurred in both groups after E coli injections; however, the subsequent development of leukocytosis in the MP group was significantly greater at +6 hours . Rectal temperatures were higher in the MP group from +1 through +4 hours than in the controls . Hyperglycemia developed initially in both groups, followed by a progressive hypoglycemia, with survivors returning to near normal blood glucose concentrations . Hemoconcentration occurred in both groups, with higher hematocrits being associated with mortality . Results support the view that methylprednisolone sodium succinate does not affect the clearance of live E coli organisms. Antonie Van Leeuwenhoek, 1979, 45(1), 103 - 11 The effect of a plasmid on growth and survival of E . coli; Dale JW et al.; We studied the growth characteristics of a pair of Escherichia coli strains, isogenic apart from the possession of a nonconjugative plasmid . There was no difference between the two strains when they were grown separately . In mixed culture, a second slow phase of growth that normally occurred following the end of rapid exponential growth, was absent from the plasmid-carrying strain . This resulted in a considerable decrease in the proportion of the cells that carried the plasmid after overnight incubation . The effect of different conditions of growth is reported . The plasmid-carrying strain survived extended incubation (150 days at 37 degrees C) as well as did the plasmid free strain separately . In a mixture, the proportion of plasmid-carrying cells declined rapidly, and none was detected after 100 days. Vet Med Nauki, 1979, 16(10), 74 - 80 {Hemagglutinating activity and morphology of antigen K 99 in enterotoxic strains of E . coli isolated from calves}; Petkov M et al.; The hemagglutination activity and morphology of antigen K 99 in enterotoxic E . coli strains isolated from calves was studied . It was proven that antigen K 99 is produced not at 18 degrees C, but at 37 degrees C . All K 99+ E . coli strains react with absorbed anti K 99 serum, showing various anti-agglutination titers . The hemagglutination activity of K 99+ E . coli strains is inhibited by absorbed K 99 antiserum . In immunodiffuse tests all K 99+ E . coli strains react by producing a single precipitation line . It is proven electronmicroscopically that on the surface of the bacterial cell of K 99+ E . coli strains is observed a filamentous structure, consisting of numerous fine fibers which give it a fibriform outlook . No such morphological structures are observed in K 99- E . coli strains. Nucleic Acids Symp Ser, 1979, (6), s195 - 8 Synthesis of the nascent strand of tRNAfMet from E coli; Ohtsuka E et al.; Oligonucleotides corresponding to the total tRNAfMET FROM E . coli have been synthesized . These fragments were joined by using RNA ligase to yield quarter molecules . The 5'-quarter molecule showed 84% amino acid acceptor activity when it was combined with the natural three quarter molecule. Vet Med Nauki, 1979, 16(9), 24 - 8 {Hemagglutinating activity of enterotoxic strains of E . coli isolated from calves}; Petkov M et al.; The manose-resistant hemagglutination activity of 272 E . coli strains isolated from calves sick or dead of colibacteriosis, 43 of which were enteropathogenic, was assessed . Strain enteropathogeneity was determined after the method of Smith and Halls (1967) . It was established that 38 (88.3%) of the 43 enteropathogenic strains cause full or partial hemagglutination of horse or pig erythrocytes . Manose-resistant hemagglutination was not observed in the non-enteropathogenic E . coli strains . Manose-resistant hemagglutination of enterotoxic E . coli strains is in relation with their enteropathogeneity. Mol Gen Genet, 1979, 177(1), 129 - 37 Indirect and intragenic suppression of the lexA102 mutation in E . coli B/r; Volkert MR et al.; In Escherichia coli B/r the expression of UV inducible (SOS) functions is under the control of the recA and lexA genes . In this study we have characterized mutants which are altered in their ability to express SOS functions . These mutants were isolated as UV resistant UV nonmutable (Rnm) derivatives of the lexA102 uvrA155 mutant strain WP51 . The UV resistance of these Rnm strains is a result of the suppression of lexA102 mediated UV sensitivity . Genetic mapping of rnm mutations shows that the two predominant classes, rnmA and rnmB, map in or very near the lexA and recA genes respectively . rnmA mutations differ from rnmB with regard to recA protein synthesis, rnmA mutations do not restore the ability to express high levels of recA protein after UV treatment whereas rnmB mutations result in constitutive expression of high levels of recA protein . However, both rnmA and rnmB mutant strains inhibit postirradiation DNA degradation . This shows that in rnmA strains, high levels of recA protein are not needed to inhibit postirradiation DNA degradation . The genetic map location and constitutive expression of recA protein synthesis resulting from rnmB mutations suggests that they are operator constitutive mutations of the recA gene . The result that the lexA+ gene is required for the expression of UV mutagenesis in rnmB mutants shows that high levels of recA protein do not circumvent the need for the lexA+ gene product in this process . Thus, while the lexA gene product is required for the induction of recA protein synthesis, lexA must have an additional role in UV induced mutagenesis. Contrib Microbiol Immunol, 1979, 6, 78 - 88 Recombination between the plasmid prophages P1 and P7 and the E . coli chromosome; Chesney RH et al.; The prophages of the related temperate phages P1 and P7, which normally exist as plasmid DNA, suppress E . coli dnaA(Ts) by integrating into the host chromosome . Integratively suppressed strains may either be capable of producing phage or may have prophage deletions . In strains containing non-defective prophages, the location of the site on the prophage used for integrative recombination was identified by use of restriction analysis and DNA-DNA hybridization techniques . At least seven different integration sites were found on the prophage; the site used most often may be at the 'end' of the genetic map generated by vegetative phage crosses . For suppression of P1 and P7, the sites on the host chromosome utilized for prophage integration are not distributed randomly. Vet Med Nauki, 1979, 16(1), 72 - 6 {Transmissible drug resistance in strains of E . coli isolated from birds}; Kandov P; A total of 97 strains of Escherichia coli, resistant either to one or to several theraupeutic agents and isolated from young and adult birds, were studied for the presence of transmissible R plasmids . Transmissible drug resistance was demonstrated with 37 per cent of the strains . The transmission of such resistance was manifested in highest percent in the case of ampicillin and chloramphenicol, followed by sulphathiazole and tetracycline . The R plasmids established in multi-drug resistant strains with three markers and more, were found to bear high percent determinants of resistance to chloramphenicol and in lower percent such to sulphathiazole and tetracycline . The same strains presented R plasmids that bore determinants of resistance to five therapeutic agents (Tc, Su, Cm, Mm, Nm) and to three therapeutic agents (Cm, Ap, Tc) and (Cm, Su, Km). Chem Biol Interact, 1979, 28(1), 61 - 70 Biological activity of metal complexes . I . Interaction of pt(II), pd(II) and rh(I) complexes with E . coli strains and with mice LS fibroblasts in vitro; Aresta M et al.; The effects of a number of Pt(II, Pd(II) and Rh(I) complexes against cultures of Escherichia coli (strains B, H10178, uvra-, recA-) and cultures of mice LS Fibroblasts were tested . Most of the compounds showed higher cytotoxic activity than the cis-Pt(NH3)2Cl2, the compound at present on clinical trial as antittumour drug . A new model of active compound is proposed. Ann Sclavo, 1979 Jan-Feb, 21(1), 53 - 7 {R factors influence on motility of "E . coli" and "S . typhimurium" (author's transl)}; Perduca M et al.; Influence on the motility of E . coli and S . typhimurium strains by several R factors has been studied; both classes of inhibiting and stimulating R factors have been detected; the plasmidic effect on the motility can be inverted by transfer to another carrier strain. J Perinat Med, 1979, 7(1), 23 - 6 Neonatal E . coli pericarditis; Wynn RJ; A review of the literature reveals only one case of neonatal Escherichia coli pericarditis . This is a case report of Escherichia coli pericarditis occurring in a two day old infant . The infant initially presented with lethargy and jaundice but this rapidly progressed into shock . Despite vigorous resuscitative efforts, the infant succumbed and at autopsy 30 cc of purulent fluid were obtained . Cultures of the admission blood and post-mortem pericardial effusion grew Escherichia coli . The clinical diagnosis of pericarditis is often difficult because of vague, nonspecific symptoms and signs . The symptoms are usually those of sepsis plus those of impaired circulation due to mechanical embarrassment by accumulating pericardial effusion . It is difficult to differentiate pericarditis with effusion from myocarditis and pericardial effusion secondary to congestive heart failure . The use of pericardiocentesis as a diagnostic tool and echocardiography are the most helpful techniques presently available for diagnosis . Management consists of vigorous supportive efforts, antibiotics, and drainage of the pericardial effusion . Because of the very high mortality associated with this disorder, a high index of suspicion with a vigorous diagnostic and therapeutic approach to the patient is indicated. Circ Shock, 1979, 6(4), 343 - 55 Prolonged shock in the monkey following live E coli organism infusion; Coalson JJ et al.; Responses of the rhesus monkey to the administration of live Escherichia coli organisms during an observation of 0--27 hours were studied . Nine monkeys were infused for 30 minutes with live E coli organisms, the dose ranging between 7.6 X 10(9) and 3.0 X 10(11) organisms/kg . Three of nine animals survived for 24 hours or longer . Nonsurvivors demonstrated significant hypotension, hypoglycemia, and hypoinsulinemia, while survivors showed lesser degrees of physiologic derangement . Findings were hepatic sinusoidal fibrin thrombi and hepatocellular damage accompanied by elevated serum enzymes . The kidney did not show glomerular fibrin thrombi; however, tubular lesions were clearly evident and increases in blood urea nitrogen levels and endogenous creatinine were documented . Lungs of animals surviving longer contained fewer polymorphonuclear leukocytes and platelets than were seen in acute shock studies . This study emphasizes the importance of monitoring the nonhuman primate during an extended time period, since many significant pathophysiologic responses occur after eight hours of observation. Biochimie, 1979, 61(8), 881 - 9 Function of individual E . coli 30 S ribosomal proteins as determined by in situ immunospecific neutralization: a tentative classification; Lelong JC et al.; The accessibility of each 30S subunit protein to their cognate antibodies (IgG or Fabs) having been previously well established, the effect of their in situ specific neutralization by monovalent IgG fragments (FabI) are reported for five reactions: 1) T4 and R17 RNA directed protein synthesis: 2) polyphenylalanine synthesis: 3) enzymatic Phe-tRNA binding in the presence of 30S + 50W subunits: 4) fMet-tRNAf binding to the 30S subunit in the presence of initiation factors IF1, IF2, IF3; 5) coupling with lambda plac DNA transcription of the initial translation step (i.e., interaction of IF3 activated 30S subunits with nascent mRNA, in the absence of tRNA) . According to evident similarities in their inhibition pattern concerning the five reactions tested, 30S subunit proteins can be classified in five categories which are discussed in terms of functional topography. Quad Sclavo Diagn, 1978 Dec, 14(4), 536 - 50 {Pathogenicity of E . coli: biological aspects and problems related to laboratory diagnosis (author's transl)}; Patriarca P et al.; The biological properties which may contribute to the pathogenicity of E . coli are reviewed in this article . Specifically the following topics are discussed in detail: 1) adhesion to the intestinal epithelial cells, 2) production of enterotoxins, 3) invasiveness of and ability to multiply within the epithelial cells, 4) insensitivity to complement lysis or inability to activate the alternative pathway of complement, 5) resistance to phagocytic killing . The various techniques which might be of potential usefulness in the clinical laboratory to test the parameters of the pathogenicity of E . coli are briefly outlined . The dissociation between the definition of pathogenicity, as established on the basis of the results of E . coli serotyping, and the criteria of pathogenicity listed above is brought to the attention of the reader . As specificity regards the toxinogenicity, what emerged from a survey of the literature, was that only one of the so called "enteropathogenic" strains of E . coli, according to the serotype classification, was found to produce an enterotoxin. Int J Radiat Biol Relat Stud Phys Chem Med, 1978 Dec, 34(6), 537 - 45 The response of E . coli Bs-1 to tritium-beta particles under aerated and anoxic conditions; Lunec J et al.; E . coli Bs-1 cells were exposed to acute doses of tritium-beta particles by suspension in tritiated water for known lengths of time . The resulting survival rate was compared with that obtained for external irradiation with 7 MeV electrons . The o.e.r . measured for tritium-beta s was not significantly different from the value of 2.15 measured for 7 MeV electrons . The r.b.e . of the tritium beta s relative to 7 MeV electrons was 1.21 in both air and nitrogen . These results were compared with existing data for low voltage electron irradiations and with track segment studies of the effect of varying LET on the radiosensitivity of E . coli Bs-1. Can J Microbiol, 1978 Dec, 24(12), 1607 - 13 Factors influencing the in vivo stability of L-serine deaminase activity in E . coli K12; Beeraj RD et al.; L-Serine deaminase (L-SD) is unstable in intact cells of Escherichia coli K12 . The extent of this instability is dependent on the nitrogen content of the medium in which the enzyme is synthesized, and on that in which it is tested . Enzyme activity in cells grown with an inorganic nitrogen source is unstable in the presence of inorganic nitrogen; enzyme activity in cells grown with an organic nitrogen source is unstable in the presence of the amino acids glycine and leucine. Nucleic Acids Res, 1978 Dec, 5(12), 4933 - 47 RNA-RNA interactions in the binding site of protein L24 on 23S ribosomal RNA of E . coli . II . Sequence analysis of the interacting fragments; Krol A et al.; A ribonucleoprotein complex containing several RNA subfragments from the 5' part of 23S RNA was recovered after digestion of the reconstituted complex between 23S RNA and protein L24 . It was suggested in the preceding paper that the RNA subfragments 4B, 10A and 9, which are widely separated in the sequence, strongly interact . These subfragments were previously partially sequenced by the classical fingerprinting methods . Their sequences have now been completed with rapid new RNA sequencing methods . We propose here a base-pairing model showing how these subfragments may interact with one another. Nucleic Acids Res, 1978 Dec, 5(12), 4837 - 53 Participation of X47-fluorescamine modified E . coli tRNAs in in vitro protein biosynthesis; Sprinzl M et al.; The reaction of fluorescamine with primary amino groups of tRNAs was investigated . The reagent was attached under mild conditions to the 3'-end of tRNAPhe-C-C-A(3'NH) from yeast and to the minor nucleoside x in E . coli tRNAArg, tRNALys, tRNAMet, tRNAIle and tRNAPhe . The primary aliphatic amino groups of these tRNAs react specifically so that the fluorescamine dye is not attached to the amino groups of the nucleobases . E . coli tRNA species modified on the minor nucleoside X47 can all be aminoacylated . An involvement of the minor modified nucleoside X47 in the tRNA: synthetase interaction is detected . Native tRNALys-C-C-A from E . coli can be phenylalanylated by phenylalanyl-tRNA synthetase from yeast, whereas this is not the case for fluorescamine treated tRNALys-C-C-A(XF47) . Pre-tRNAPhe-C-C-A(XF47) forms a ternary complex with the elongation factor Tu:GTP from E . coli, binds enzymatically to the ribosomal A-site and is active in poly U dependent poly Phe synthesis . Fluorescamine-labelled E . coli tRNAs provide new substrates for the study of protein biosynthesis by spectroscopic methods. Nucleic Acids Res, 1978 Dec, 5(12), 4613 - 23 The attenuator of the tryptophan operon in E.coli: rho-mediated release of RNA polymerase from a transcription termination complex in vitro; Fuller RS et al.; In vivo, termination of transcription at the attenuator site of the tryptophan (trp) operon of E . coli is influenced by the protein termination factor rho . In vitro, termination does not depend on rho factor, and is very efficient in a purified system consisting only of RNA polymerase, the DNA template, nucleoside triphosphates, and buffer . The extent of termination in this system is unaffected over a wide range of salt and nucleoside triphosphate concentration . However, there is a 10-fold stimulation of trp leader mRNA synthesis if rho factor is present during the transcription reaction . This stimulation occurs only at low molar ratios of polymerase to template, and can be blocked by rifampicin . It is thus most likely due to the recycling of RNA polymerase molecules that have been released from the attenuator site by rho factor . In fact, transcription of the trp leader region in vitro results in the fomration of a stable termination complex which can be observed on sucrose gradients or by binding to nitrocellulose filters . These data indicate that a major function of rho at the trp attenuator is to release completed transcripts from a pre-formed termination complex, rather than to cause the cessation of elongation. Biokhimiia, 1978 Dec, 43(12), 2183 - 8 {The effect of guanosinetetraphosphate on rRNA synthesis in E . coli extracts}; Perel'man BV et al.; The synthesis of rRNA in the ribosome-free extracts S100 of E . coli cells was about 30 and 60% of total transcript when E . coli DNA and DNA of lambda rifd 18 phage were used respectively . The synthesis of rRNA with both types of DNA was inhibited in 5--6 times by 0.8 mM ppGpp, while the synthesis of total RNA decreased only two-fold . Selective action of ppGpp on rRNA synthesis is due to the intensive inhibition of the initiation of transcription of the appropriate genes . The rRNA synthesis and the inhibitory capacity of ppGpp was shown to dependend on the KCl concentration in S 100 extracts . These results indicate that ppGpp is the main factor controlling rRNA synthesis both in isolated RNA polymerase system and in cell-free extracts. Cell, 1978 Dec, 15(4), 1221 - 30 Sensory adaptation mutants of E . coli; Parkinson JS et al.; The ability of E . coli to adapt to constant levels of attractant and repellent chemicals was studied by examining the patterns of flagellar movement in cells subjected to abrupt concentration changes . Wild-type bacteria exhibited transient responses to such stimuli, in support of previous findings . Nonchemotactic mutants of the cheX class responded to both attractants and repellents, but were unable to terminate these behavioral changes as long as the stimulating chemical was present . The sensory adaptation defect of cheX strains may be due to an inability to methylate several cytoplasmic membrane proteins that initiate changes in flagellar movement in response to chemoreceptor signals . Based on these results, possible mechanisms of stimulus transduction and sensory adaptation during chemotaxis are discussed. Biokhimiia, 1978 Dec, 43(12), 2154 - 62 {Aminoglycoside-3'-phosphotransferase I from aminoglycoside-polyresistant strain E . coli 182}; Ganelin VL et al.; An aminoglycoside-3'-phosphotransferase I catalyzing phosphorylation of some aminoglycoside antibiotics with the 3'-hydroxyl group has been purified from the cells of aminoglycoside resistant strain E . coli 182 by competitive affinity chromatography on neomycin-Sepharose and gel-filtration on Sephadex G-100 . The product of enzymatic phosphorylation of kanamycin A was isolated and identified as kanamycin-3'-phosphate by NMR, thin-layer chromatography and chemical characterization . The kinetic properties of the enzyme were studied . The pH-optimum was between 7,8--8,0; the {S}0.5 values for kanamycin, neomycin and paromomycin were 2.10(-5) M, the energy of activation was 15,9 kcal/mol . The bivalent cations were required for activity of the enzyme, Mg2+ was the most effecient . The relative aminoglycoside antibiotics containing no 3'-hydroxyl group were competitive inhibitors of the enzyme activity with Ki values close to {S}0.5. Biokhimiia, 1978 Dec, 43(12), 2261 - 4 {Affinity alkylation of E . coli RNA-dependent DNA polymerase with TTP gamma-amidate derivatives}; Buneva VN et al.; TTP gamma-benzylamidates are shown to act as competitive inhibitors of poly(dT) synthesis catalyzed by E . coli RNA-dependent DNA polymerase . The KM value for TTP as well as KI values for the gamma-analogues have been determined . TTP gamma-4-(N-2-chloroethyl-N-methyl-amino)benzylamidate is shown to be an effective affinity reagent for this enzyme. Mol Gen Genet, 1978 Nov 9, 166(3), 329 - 36 Functional mRNA half lives in E . coli; Pedersen S et al.; Analysis of the synthetic rate of individual protein species at various times after complete inhibition of transcription with either streptolygidin or rifampicin was carried out by two-dimensional polyacrylamide electrophoresis of total Escherichia coli cell extracts . The decay rate of the potential to synthesize different proteins was assumed to be equal to the functional decay rate of the corresponding mRNA . We conclude the following: (a) The tufA and tufB messengers have different half lives (3.0 and 2.4 min, respectively) . (b) Different genes within the same transcriptional unit can have different half lies (S7, EGF and EFTuA--2.5, 3.8 and 3.0 min, respectively) . (c) There is at least a twenty-fold variation in individual mRNA half lives in E . coli; ribosomal protein S1 mRNA was observed to have the shortest half life in the cell (40 sec), while the longest observed half life was approximately 20 min (all values at 30 degrees C) . (d) Addition of rifampicin increases the absolute rate of RNA polymerase subunit alpha and beta synthesis two-fold . (e) The induction of the synthesis of alpha subunit of RNA polymerase takes place without a concomitant induction of ribosomal protein S4 and L17, which are reported to be on either side of alpha in the same transcriptional unit. Nature, 1978 Nov 2, 276(5683), 33 - 7 Identification of a single promoter in E . coli for rplJ, rplL and rpoBC; Linn T et al.; A set of restriction fragments cloned into phage lambda vectors has allowed us to locate a site necessary for full rpoBC expression . We find that these genes for the two large subunits of RNA polymerase and the genes, rplL and rplJ, for two ribosomal proteins, form a single operon. Cell, 1978 Nov, 15(3), 1055 - 66 Structural analysis and in vitro processing to p5 rRNA of a 9S RNA molecule isolated from an rne mutant of E . coli; Ghora BK et al.; A temperature-sensitive mutant of E . coli, rne (RNAase E-), accumulates a number of relatively small RNA molecules at the nonpermissive temperature . One of these molecules, 9S, contains 5S rRNA sequences . The 9S RNA can be processed in vitro to 5S (p5) and a 4S-sized molecule . The 9S and the p5 and 4S RNAs processed from it were all characterized by RNAase T1 fingerprinting and pancreatic RNAase redigestion analysis . Unique oligonucleotides found in the p5 and the 4S RNA are present as unique oligonucleotides in the 9S RNA, suggesting that each 9S molecule contains one 5S and one 4S RNA moiety . Since the 9S RNA contains about 420 nucleotides, and intervening sequences are not known to exist in E . coli, the 5S an 4S RNAs cannot be more than 200 nucleotides apart in the genome . E . coli contains at least three different sequence variants of 5S rRNA, all of which can be identified in the 9S transcript, indicating that 9S RNA is transcribed from most, if not all, of the active rRNA genes, and that RNAase E processes transcripts derived from all these rRNA genes . No modified bases were found in the 4S RNA, nor was its sequence compatible with the known sequences of tRNAs found near the 5S rRNA . We therefore conclude that the 9S RNA doses not contain tRNA, and that the tRNA molecules located near the 5S rRNA are distal to it. Nucleic Acids Res, 1978 Nov, 5(11), 4215 - 23 Isolation of Q nucleoside precursor present in tRNA of an E . coli mutant and its characterization as 7-(cyano)-7-deazaguanosine; Noguchi S et al.; One of the E . coli mutants selected for deficiency of modified nucleoside Q was found to contain an analogue of Q and normal guanosine in place of Q . The analogue of Q, designated as preQo, was isolated on a large scale from purified tRNATyr containing preQo . The structure of preQo was determined to be 7-(cyano)-7-deazaguanosine by comparison of its ultraviolet absorption spectra, thin-layer chromatographic mobility and mass spectrum with those of synthetic material. Gene, 1978 Nov, 4(3), 241 - 59 Transcription and translation in E . coli of hybrid plasmids containing the catabolic dehydroquinase gene from Neurospora crassa; Alton NK et al.; Two hybrid plasmids which carry the gene for Neurospora crassa catabolic dehydroquinase (C-DHQase) and complement an aroD6 (dehydroquinase-deficient) auxotroph of Escherichia coli have been analyzed . One of these contains a 2.9 kilobase (kb) fragment cloned in the HindIII site of plasmid pBR322 (pVK57) and the other contains a 6.8 kb fragment cloned in the PstI site (pVK88) . Restriction enzyme mapping of these plasmids has demonstrated that the 2.9 kb fragment is totally contained within the 6.8 kb fragment . When the polarity of either the HindIII fragment or PstI fragment was reversed with respect to pBR322 no effect was observed on either the ability of the hybrid to complement an aroD- auxotroph or on the level of C-DHQase activity . In vivo transcription of plasmid pVK88 in both orientations was analyzed by RNA-DNA hybridization and by the techniques developed by Southern (1975) . Approx . 40% of the plasmid-directed transcription occurred from the cloned PstI fragment and 60--70% of these N . crassa transcripts were encoded by the 2.9 kb HindIII fragment . The Southern technique allowed a further localization of the region of most extensive transcription to a 1.8 kb HindIII-EcoRI fragment . Biochemical analysis revealed that the C-DHQase protein produced by strains harboring pVK57 and pVK88 in either orientation was identical to the N . crassa enzyme . Furthermore, when these plasmids were segregated into minicells and labeled with 14C amino acids, the C-DHQase protein was synthesized at a level comparable to other plasmid-encoded proteins . Taken together, these experiments demonstrate that transcription is efficiently initiated in E . coli from a site on the cloned N . crassa DNA and that the resulting C-DHQase mRNA is efficiently and accurately translated. Antibiotiki, 1978 Nov, 23(11), 989 - 93 {Makeup and properties of E . coli cells with a varying level of resistance to tetracycline}; Kuzina ZA et al.; Lipopolysaccharide composition of tetracycline sensitive and resistant strains of E . coli was studied comparatively . It was shown that that resistance of E . coli to tetracycline was probably due to the differences in the lipopolysaccharide component composition of the outer membrane . On the basis of the activity comparison of the Mg2+- and Ca2+-activated ATP-ase of the membrane fraction of the tetracycline sensitive and resistance strains of E . coli it was concluded that the resistance development in the strains tested to tetracycline was not associated with the changes in the ATP-ase activity. Acta Paediatr Scand, 1978 Nov, 67(6), 705 - 8 Immunodeficiency in Down's syndrome . Titres of "natural" antibodies to E . coli and rabbit erythrocytes at different ages; Ugazio AG et al.; "Natural" antibody titres to E . coli O antigens of different serotypes and to rabbit red blood cells were determined in 86 subjects with Down's syndrome and 79 mentally retarded but chromosomally normal controls ranging in age from 10 months to 52 years . Subjects in the two groups were matched for sex, age and socio-environmental conditions . Titres of both antibodies, assessed by haemagglutination, were significantly lower in subjects with DS in the 1 to 5 year old group . E . coli antibodies transiently increased to normal values in subjects with DS during the second 5 years of life, thereafter rapidly declining to levels significantly lower than those observed in controls . The titres of antibodies to rabbit erythrocytes in subjects with Down's syndrome showed a more variable course transiently approaching normal values in the 7-10 year group and after 20 years of age . These data are interpreted as further evidence for the existence of a congenital immunodeficiency in Down's syndrome. Wien Klin Wochenschr, 1978 Oct 27, 90(20), 717 - 21 {Inhibition of opsonization of E . coli by enzyme-treated gammaglobulin (author's transl)}; Eibl M et al.; The influence of Cohn fraction II, pepsin- and plasmin-treated gammaglobulin on the opsonization of E . coli 0111 was investigated . Normal serum at different dilutions, as well as serum of patients with different forms of antibody deficiency syndromes were tested . No effect was observed by pre-incubation of the bacteria in these gammaglobulins if concentrated or 1:10 diluted serum was used for opsonization . In diluted serum Cohn fraction II potentiated and pepsin-treated gammaglobulin competitively inhibited opsonization, whilst plasmin-treated gammaglobulin potentiated at the low and competitively inhibited at higher dilutions . In serum from patients with antibody-deficiency syndromes, potentiation of opsonization by Cohn fraction II and competitive inhibition by pepsin- and plasmin-treated gammaglobulins was already seen at low serum dilutions. Nature, 1978 Oct 19, 275(5681), 617 - 24 Phenotypic expression in E . coli of a DNA sequence coding for mouse dihydrofolate reductase; Chang AC et al.; The construction and analysis of bacterial plasmids that contain and phenotypically express a mammalian genetic sequence are described . Such plasmids specify a protein that has enzymatic properties, immunological reactivity and molecular size characteristic of the mouse dihydrofolate reductase, and render host cells resistant to the antimetabolic drug trimethoprim. Nucleic Acids Res, 1978 Oct, 5(10), 3759 - 73 A computer aided oligonucleotide analysis provides a model sequence for RNA polymerase-promoter recognition in E.coli; Scherer GE et al.; A novel computer procedure has been used to search for homology among 17 known procaryotic promoter sequences . A model sequence, :formula: (see text), is compatible with the properties of all known promoter and operator mutations, predicts base positions for the initiation of RNA synthesis coinciding with those determined experimentally, is compatible with current models for the regulation of transcription, suggests that RNA polymerase could recognize the DNA double helix firstly in the B conformation then in the A. Int J Radiat Biol Relat Stud Phys Chem Med, 1978 Oct, 34(4), 317 - 27 Extensive and equivalent repair in both radiation-resistant and radiation-sensitive E . coli determined by a DNA-unwinding technique; Ahnstrom G et al.; The extent of strand breakage and repair in irradiated E . coli B/r and Bs-1 was studied using a DNA-unwinding technique in denaturing conditions of weak alkali . Although these two strains show widely different responses to the lethal effects of ionizing radiation, they both have an equal capacity to repair radiation-induced breaks in DNA . Oxygen enhancement ratios for the killing of B/r and Bs-1 were respectively 4 and 2; but after repair in non-nutrient or nutrient post-irradiation conditions, the oxygen enhancement values for the residual strand breaks were always the same for the two strains . The equal abilities of E . coli B/r and E . coli Bs-1 to remove the strand breaks measured by this weak-alkali technique leads us to suggest that some other type of damage to either DNA or another macromolecule may play a major role in determining whether or not the cells survive to proliferate. Gene, 1978 Oct, 4(2), 137 - 52 Cloning of an E . coli ribosomal RNA gene and its promoter region from lambdarifd18; Kiss A et al.; The DNA of the specialized transducing phage lambdarifd18, which carries a bacterial rRNA transcription unit, was digested with restriction enzymes EcoRI and/or BamHI . Attempts were made to clone fragments containing the presumed rRNA promoter region or the entire rRNA gene in RSF2124 or pBR313 plasmid vectors with the following results: (1) We failed to clone an EcoRI fragment with the rRNA promoter region in plasmid RSF2124 . (2) A smaller EcoRI-BamHI fragment with the rRNA promoter was also unclonable by itself, but one recombinant was found containing this fragment together with another large (7 Mdaltons) fragment, derived from phage lambda . The presence of this large fragment proved to be essential . The identity of these DNA fragments in the recombinant clone was confirmed by redigestion with several restriction enzymes, hybridization with rRNA, and in vitro transcription experiments, which showed preferential rRNA transcription . (3) A BamHI fragment encompassing the entire rRNA gene was easily cloned . Such stable clones carried a doubled number of rRNA genes . In vitro transcription using the recombinant plasmid resulted in 70% rRNA transcription . These recombinant clones allow the easy purification of the relevant DNA fragments for further investigation including sequencing. Cell, 1978 Oct, 15(2), 527 - 39 Processing of rRNA by RNAase P: spacer tRNAs are linked to 16S rRNA in an RNAase P RNAase III mutant strain of E . coli; Gegenheimer P et al.; To determine which enzymes are responsible for the processing cleavages of ribosomal RNA transcripts in Escherichia coli, we constructed a mutant strain lacking RNAase III and containing a thermolabile RNAase P . At the nonpermissive temperature, this strain accumulates a novel "19S" RNA species which contains 17S precursor rRNA sequences covalently linked to tRNA sequences transcribed from the ribosomal RNA spacer region between the 16S and the 23S rRNA cistrons . In vitro treatment of 19S RNA with cell extracts releases tRNA2Glu and other tRNA species . These "spacer" tRNA sequences are apparently not contained with the 18S RNA species found in an RNAase III- RNAase P+ cell . RNAase P-deficient extracts are incapable of cleaving space tRNA from 19S RNA, indicating that RNAase P is required for the release of spacer tRNAs from rRNA transcripts of E . coli cells. Biokhimiia, 1978 Oct, 43(10), 1783 - 9 {Interrelationship between metabolic and genetic regulation of alkaline and acid phosphatases in E . coli cells}; Nesmeianova MA et al.; The effect of exogenous orthophosphate and mutations in regulatory genes of alkaline phosphatase on the level of nonspecific acid phosphatase was studied . The level of this enzyme as well as the level of alkaline phosphatase were shown to be regulated by exogenous orthophosphate being derepressed under phosphate starvation . The derepression of acid phosphatase is accompanied by more rapid secretion of enzyme from membranes to soluble fraction . Mutations in all the four regulatory genes decrease the level of enzyme in cells . Genes phoR and phoS, participating in regulation of alkaline phosphatase, are required for the derepression of acid phosphatase under the conditions of phosphate starvation. Br J Pharmacol, 1978 Oct, 64(2), 185 - 91 E . coli endotoxin shock in the dog; treatment with lidocaine or indomethacin; Fletcher JR et al.; 1 Dogs treated with lidocaine (1 mg kg-1 h-1) or indomethacin (1.5 mg/kg) before and after an LD60 dose (1 mg/kg) of E . coli endotoxin survived for at least 72 h . 2 Although all dogs in both treated groups survived, only those treated with indomethacin were significantly protected against the fall in the arterial blood pressure 1 to 2 min following endotoxin administration . 3 Endotoxin increased the plasma prostaglandin F2alpha (PGF2alpha) concentration in the control and lidocaine-treated groups, however, no increase was observed with indomethacin treatment . 4 Neither lidocaine nor indomethacin alone had any significant effect on the parameters measured in this model . 5 Following the administration of endotoxin, lidocaine-treated animals had significantly decreased plasma fibrinogen concentrations when compared to the other groups . 6 This study suggests that lidocaine, a local anaesthetic and a drug widely used for cardiac arrhythmias, might offer protection in endotoxin shock. Eur J Immunol, 1978 Oct, 8(10), 688 - 92 Immune response against the beta-galactosidase enzyme of E . coli at precursor cell level . I . Analysis of the secondary repertoire in BALB/c mice; Accolla RS et al.; The BALB/c secondary response against the beta-galactosidase (beta-gal) enzyme of E . Coli was analyzed at the precursor cell level by using the splenic focus technique . Our results indicate that in immunized mice, one out of 18 000 B cells is able to recognize beta-gal . Among the families of anti-beta-gal monoclonal antibodies, a subset of specific antibodies was detected which is capable of protecting the enzyme from heat denaturation . The frequency of clones making protecting antibodies is 1 out of 90 000 and appears to be fairly constant among different individual mice . Further, the degree of heterogeneity of protecting antibodies analyzed in one individual is very high (250-fold difference in affinity) but comparable to other secondary repertoires . Specific frequencies are compared with previous findings relative to secondary responses against artificial haptens . It is suggested that a different type of recognition exists between protein determinants and artificial haptens . In addition, the relatively high proportion of clones making antibodies of the protecting type suggests that only a small proportion of antigenic sites on the beta-gal is actually able to stimulate an immune response. Nucleic Acids Res, 1978 Oct, 5(10), 3855 - 69 Phosphorus-31 NMR studies of E . coli ribosomes; Tritton TR et al.; Phosphorus-31 nuclear magnetic resonance spectra, relaxation times and nuclear Overhauser (NOE) enhancement have been measured for E . coli ribosomes, subunits and rRNA . NOE and T1 experiments reveal that the phosphorus relaxation in this organelle is largely dipolar in origin . Moreover these results imply the presence of internal motion within the RNA chain with a correlation time of about 3-5 x 10(-9) sec . In all cases the predominant resonance is centered at about -1.5 ppm (relative to 85% H3PO4) as expected for a phosphodiester linkage where there is a large degree of double helix . The linewidth narrows by about a factor of four when the ribosomal proteins are removed indicating a substantial immobilization of the RNA when it is assembled into the ribosome . In addition to the phosphodiester resonance, ribosomes also reveal one or two narrower resonances shifted to low field by 1-4 ppm . Based on the observation that these resonances show a pH dependent chemical shift, we assign them to phosphate monoesters i.e . terminal 3' or 5' phosphate groups . These terminal phosphates are due to short oligomers of RNA derived from the terminus of the chain. Mol Biol (Mosk), 1978 Sep-Oct, 12(5), 1085 - 95 {Modification of one tRNA recognition site of phenylalanyl-tRNA synthetase from E . coli MRE-600 with N-chlorambucilyl-phenylalanyl-tRNA}; Ankilova VN et al.; Affinity labelling of phenylalanyl-tRNA synthetase from E . coli MRE-600 with N-chlorambucilyl-phenylalanyl-tRNA results in a binding of 1 mole of the reagent per 1 mole of the enzyme . Exhaustive alkylation of phenylalanyl-tRNA synthetase completely blocks the aminoacylation and partially inhibits the reaction of ATP--{32P}pyrophosphate exchange . Removal of the tRNA moiety of the reagent by hydrolysis of the ester bond N-chlorambucilyl-phenylalanine and terminal adenosine does not result in a restoration of ATP--{32P}pyrophosphate exchange and aminoacylation activity . The latter result may testify a chemical modification of amino acid residues essential for enzymatic activity . Possibility of blocking one of the two tRNA binding sites is discussed. Biokhimiia, 1978 Sep, 43(9), 1718 - 20 {Sensitivity of chromosomal and plasmid E . coli DNA to restriction endonuclease Eco RII}; Guseinov OA et al.; It was shown that E . coli C, E . coli MRE 600 DNA, and also plasmid DNA of Col E1, RSF 2124 from E . coli K-12, and plasmid DNA from E . coli MRE 600 were completely resistant against restriction endonuclease R . Eco RII . Plasmid DNAs of Col E1, RSF 2124 amplificated for 4 hours in the presence of chloramphenicol are sensitive to R . Eco RII but after 16-hour amplification in the presence of chloramphenicol these DNAs acquire complete resistance against R . Eco RII . These data point to the slower rate of modification of DNA in vivo by DC-methylases of Eco RII type in comparison with DNA methylase Eco RII. Biokhimiia, 1978 Sep, 43(9), 1680 - 7 {Induction of E . coli alkaline phosphatase synthesis in cells preincubated at low temperatures}; Evdokimova OA et al.; Cell preincubation at lowered t degrees was found to result in increased alcaline phosphatase synthesis . The ability of cells for increased alcaline phosphatase synthesis correlates with increased content of cis-vaccinic acid and higher liquidity of lipids . It has been ascertained that modifications caused by cell preincubation at lowered t degrees favour the greater stability of mRNA coding the alcaline phosphatase. Cell, 1978 Sep, 15(1), 231 - 6 Isolation and characterization of a promoter mutant in the str ribosomal protein operon in E . coli; Post LE et al.; The lambda fus3 transducing phage carries several operons for ribosomal proteins of E . coli, including the str operon . A mutant transducing phage with a promoter mutation in this operon has been isolated . This mutant shows reduced stimulation of synthesis of proteins encoded by the operon, S12, S7, and elongation factors G and Tu, in ultraviolet-irradiated cells . This mutation also abolishes in vitro transcription from the str promoter . The DNA sequence of the mutant promoter shows that it is a point mutation 6 bases upstream from the in vitro transcription start site, changing the "Pribnow box" sequence from TAAAATT to TAAAACT . These results indicate that the site altered by the mutation, which is in the region just preceding the transcription start site, is important for the expression of the str operon. Antibiotiki, 1978 Sep, 23(9), 779 - 85 {2 types of auxotrophic mutants occurring by insertion of the ampicillin transposon into the chromosome of E . coli K-12}; Gordienko IV et al.; Insertion of transpozone TnI determining ampicillin resistance into the E . coli K-12 chromosome resulted in formation of auxothrophic mutants of 2 types . The mutants of the first type carried thermosensitive mutation resulting in auxotrophy with respect to isoleucine at a temperature of 43 degrees C . Such mutants occurred with high frequency (up to 14 per cent with respect to the number of the survived cells with the chromosomes carrying inserted TnI) and had capacity for reversion to the phenotype of the wild type . The mutants of the second type occurred with a frequency 20--180 times lower than that of the mutants of the first type and did not reverse to the phenotype of the parent bacteria . It was found that the chromosome of E . coli K-12 possessed at least 7 sites available for transpozone TnI insertion. Biokhimiia, 1978 Sep, 43(9), 1640 - 7 {Effect of mutations in regulatory genes for alkaline phosphatase on the phosphohydrolase spectrum of E . coli periplasm}; Maraeva OB et al.; The isoform spectra of alkaline and acid phosphatase, pyrophosphataes, and ATPase in periplasm of E . coli were studied using electrophoresis in polyacrylamide gel with subsequent development of zimograms directly in the gel . Wild strains and mutants on 4 regulatory genes of alkaline phosphatase were analyzed . Mutations in regulatory genes were shown to influence the amount of each of the 3 isoforms of alkaline phosphatase and also the spectra of other phosphohydrolases. Cell, 1978 Sep, 15(1), 215 - 29 DNA sequences of promoter regions for the str and spc ribosomal protein operons in E . coli; Post LE et al.; The DNA sequences have been determined for promoter regions of two ribosomal protein operons in E . coli, the str operon and the spc operon . The site of in vitro transcription initiation within each of these promoter regions has been determined . The start site of the str operon occurs 69 bases upstream from the initiation codon of the S12 gene . The start site of the spc operon occurs 72 bases upstream from the L14 gene, and only 91 bases downstream from the termination codon of the S17 gene (which is in the preceding S10 operon) . Both promoters are similar to other sequenced promoters in that they each have an identifiable "Pribnow box" sequence 5 bases upstream from the transcription start site . The spc promoter has a long sequence of 2 fold symmetry centered within the Pribnow box; the str promoter has a shorter but similar symmetry . At positions -69 through -40 in the spc operon, another long region of symmetry is present which may be the termination signal of the preceding S10 operon . Extensive sequence similarity between the str and spc promoter regions is found downstream from the Pribnow box-that is, in a transcribed region preceding the translation start sites. Diabetologia, 1978 Aug, 15(2), 113 - 6 The effect of E . coli L-asparaginase on oral glucose tolerance and insulin release in man; Lavine RL et al.; To study the effect of E . Coli L-asparaginase on glucose tolerance and insulin release, 6 patients with neoplastic disease were subjected to 3 hour oral glucose tolerance tests with simultaneous measurement of serum immunoreactive insulin (IRI) levels before and following the intravenous administration of 5000 I . U . L-asparaginase/day for 4 days . Five of the patients exhibited a significant deterioration in glucose tolerance; however, no change was noted in their fasting glucose and IRI levels . The deterioration in glucose tolerance was associated with a decrease in the amount of insulin secreted in the first 30 minutes after the oral glucose load . The total amount of insulin released during the 3 hour test remained unchanged . These studies suggest that L-asparaginase can cause a deterioration of glucose tolerance without accompanying fasting hyperglycaemia . This may be due, in part, to a decrease in glucose-induced insulin release during the first thirty minutes following oral glucose. Acta Pathol Microbiol Scand {B}, 1978 Aug, 86(4), 193 - 9 Phagocytosis of 32P-labelled E . coli by human polymorphonuclear cells (PMN) . Adaptation of a method; Midtvedt T et al.; A system for the study of phagocytosis by human polymorphonuclear cells (PMN) is presented . The leucocytes are harvested from heparinized whole blood by the Boyum method and transferred to glass tubes to yield glass adherent monolayers of leucocytes, approximately 80% of which were PMN . A strain of E . coli labelled by 32P served as test organism. Int J Radiat Biol Relat Stud Phys Chem Med, 1978 Aug, 34(2), 101 - 8 The synthesis of DNA by DNA-membrane complexes from irradiated E . coli B/r and Bs-1: the role of the membrane; Robertson WR et al.; DNA-membrane complexes were isolated from lysed E . coli B/r and Bs-1, either by low g forces from a low salt solution, or by high g forces through a discontinuous sucrose gradient . The latter method was more gentle . Irradiation of the intact bacteria had no effect on the membrane macromolecules or on RNA components of these complexes . DNA loss was not significant after irradiation under anoxic conditions but complexes isolated from from Bs-1 irradiated in air showed an appreciable decrease in DNA content . In the presence of the appropriate nucleotide mixture, both 'free' DNA, found in the supernatant fractions, and rapidly sedimented membrane-associated DNA