Carcinogenesis, 1981, 2(1), 33 - 8 4-Chloromethylbiphenyl (4CMB): a novel mutagen and potential carcinogen; Ashby J et al.; The bacterial mutagenicity and cell transforming properties of the monocyclic alkylating agent benzyl chloride have been compared with those of its biphenyl analogue, 4-chloromethylbiphenyl (4CMB), and it is apparent that the addition of the second benzene ring greatly enhances biological activity . The possible reasons for this enhancement are discussed in relation to similar effects observed when comparing the activities of aniline with its biphenyl analogue, 4-aminobiphenyl (4AB) . The marked activity observed for 4CMB, a stable and crystalline solid, suggests that it could prove useful as a direct-acting positive control test chemical for use in short-term mutagenicity tests. Biophys J, 1981 Jan, 33(1), 93 - 106 Sensitivity of exponentially growing populations of Escherichia coli to photo-induced psoralen-DNA interstrand crosslinks; Grover NB et al.; Experimental survival curves for Escherichia coli K 12 (CR 34) were determined after exposure to 4,5',8-trimethylpsoralen and near ultraviolet light . The lethal action was shown to arise exclusively from interstrand crosslinks, cell vulnerability increasing markedly with the doubling time of the culture . To account for these results, two quite different models are considered . The first assumes that a cell survives as long as at least one copy of its genome remains undamaged; a variant of this permits repair by DNA strand exchange . The second model allows for a limited period of time during which DNA repair can take place . A crosslink in a stretch of DNA due to be replicated within this interval constitutes a fatal lesion . Theoretical survival curves are computed for bacterial populations with defined age distributions and chromosome configurations . While the first model completely fails to provide a satisfactory description of the experimental results, the second model does predict the presence of a shoulder in the survival curves and, in one of its forms, it seems to agree rather well with the measured data over a wide range of crosslink concentrations and doubling times. Boll Ist Sieroter Milan, 1981, 60(1), 61 - 8 {Preliminary results on the effects of pretreatment with thymic extract on experimental endotoxin hepatitis in the mouse}; Corridori S et al.; The Authors wish to examine the protective effects which a period of pre-treatment with thymostimulin, would have on endotoxin hepatitis, induced in thymectomized and non-thymectomized animals . The test showed that the histological picture and the degree of endotoxinemia, measured with the Lymulus test, benefited from treatment with a thymic extract . This therapy was effect (and was statistically significant) in obtaining an immunorestoring effect (in the thymectomized mouse) and in inducing an immunostimulating effect (in the normal mouse). Arch Virol, 1981, 68(3-4), 249 - 56 Principles of selective inactivation of viral genome . II . Influence of stirring and optical density of the layer to be irradiated upon UV-induced inactivation of viruses; Budowsky EI et al.; Kinetics of the UV-induced (lambda = 254 nm) inactivation of phage MS2 is studied for stirred and non-stirred solutions with optical densities ranging from 0.06 to 2.1 . The extent of inactivation exhibits exponential dependence on irradiation time for stirred solutions thus indicating the homogeneity of the phage population in respect to photosensitivity of infectivity . Irradiation of the same solution without stirring results in deviation of survival curves from exponential ones (the so called "tailing"), being more pronounced the larger the optical density of the layer under irradiation and degree of inactivation . Such a deviation is conditioned by non-uniform light absorption by virions in solution in the absence of stirring . The inactivation kinetics upon UV-irradiation of the stirred and non-stirred phage solutions is rather accurately expressed by respective equations thus enabling the choice of rational conditions for a given depth of phage inactivation to be performed. Mol Gen Genet, 1981, 182(1), 44 - 52 Copy number control and incompatibility of plasmid R1: identification of a protein that seems to be involved in both processes; Burger KJ et al.; Investigations into the genetic determinants for incompatibility of miniplasmids and hybrid replicons constructed from wide type and mutant R1 revealed the presence of an incompatibility function at the junction f two small PstI fragments . These two fragments were not distinguished in earlier experiments since they have the same mobility on agarose gels . This incompatibility function is distinct from other inc-determinants of R1 (Kollek and Goebel 1979; Molin and Nordstrom, 1980) and independent of R1-type replication . By means of specific deletions and subcloning of DNA fragments, the location of this new inc-determinant could be determined further . After deletion of this inc-determinant from inc-determinant from miniplasmids, a 5-fold increase in copy number was observed which could then be reduced to a copy number of about 1 plasmid per cell by complementation with hybrid plasmids having this function . Incompatibility of miniplasmids deleted in this determinant is not reduced, whereas analogous deletions introduced into recombinant plasmids nearly abolished their incompatibility . This determinant seems to exert strong incompatibility only when cloned on pBR322 . Therefore, its main function is plasmid R1 is probably restricted to copy control . The appearance of low copy numbers of of miniplasmids carrying this determinant and of trans-acting copy control and strong incompatibility exerted by hybrid plasmids is consistently correlated with the presence of a protein of 11,000 molecular weight, synthesized in relatively large amounts in Escherichia coli minicells. Mol Gen Genet, 1981, 182(1), 12 - 8 Altered stability and integration frequency of a F' factor in RNA polymerase mutants of Escherichia coli; Gray GW Jr et al.; A number of spontaneous rifampicin-resistant (Rifr) mutants were isolated from a strain of E . coli having a deletion in the lac proA proB region of the chromosome . The stability of a F'lac proA proB episome in these mutants was determined by their sensitivity to acridine orange curing and the frequency of spontaneous loss of episomes . The Rifr mutants can be divided into three classes based on their ability to maintain the F'lac pro episome . Class I mutants (25% of the total Rifr mutants) showed high degree of spontaneous episome loss and high sensitivity to acridine orange curing . Class II mutants (55% of the total Rifr mutants), like the parent strains, showed intermediate sensitivity to acridine orange curing . Class III mutants (21% of the total Rifr mutants) showed high resistance to acridine orange curing and low frequency of spontaneous episome loss . Three-fourths of the Class II mutants were found to be Hfr as shown by their lack of the F'lac pro DNA band on agarose gel together with their ability to mobilize chromosomal markers in mating . Representative Rifr mutants from each class were selected and the Rifr mutants from each class were selected and the Rifr mutations were mapped within the proB gene for the beta beta' operon by P1 transduction . These results indicate that RNA polymerase, or the beta subunit of RNA polymerase, plays an important role in maintaining the F' lac pro episome and in the integration of the F' lac pro episome where no extensive sequence homology is involved. Mol Gen Genet, 1981, 181(4), 564 - 6 DNA synthesis in Escherichia coli during a nutritional shift-up; Zaritsky A et al.; DNA synthesis in a thymine-requiring Escherichia coli K12 strain was studied by exploiting deoxyguanosine, so simulating the behaviour of Thy+ strains . DNA synthesis is inhibited during the first 24 min after a nutritional shift-up . The new DNA/mass is lower than that predicted by current models for initiation control. Mol Gen Genet, 1981, 181(4), 535 - 40 Nitrate reductase and cytochrome bnitrate reductase structural genes as parts of the nitrate reductase operon; Bonnefoy-Orth V et al.; The existence of a nitrate-reductase operon in the tryptophane region was deduced from the effects of prophage insertion in each of chlI and chlC genes and from transposition of the Mu-mediated host DNA fragments of F-prime . This operon appears to be polarized from chlC to chlI and the gene order in the region is trp -- chlI -- chlC -- purB. Mol Gen Genet, 1981, 181(4), 491 - 6 Acetohydroxy acid synthase isoenzymes of Escherichia coli K-12: a trans-acting regulatory locus of ilvHI gene expression; Ursini MV et al.; We isolated an Escherichia coli K-12 regulatory mutation affecting the acetohydroxy acid synthase III isoenzyme . This mutation was found to lie outside the structural genes ilvHI for this isoenzyme and was designated lrs-1 . A strain carrying this mutation was found to be altered in the leucine-mediated control of ilvHI mRNA and acetohydroxy acid synthase III synthesis observed in the isogenic lrs+ strain . These alterations appeared to be a consequence of a reduced intracellular concentration of a single one of five tRNALeu isoaccepting species. Mol Gen Genet, 1981, 181(4), 441 - 7 DNA sequence of a plasmid-encoded dihydrofolate reductase; Swift G et al.; The sequence of the methotrexate-resistant dihydrofolate reductase (DHFR) gene borne by the plasmid R-388 was determined . The gene was subcloned and mapped by an in vitro mutagenesis method involving insertion of synthetic oligonucleotide decamers encoding the BamHI recognition site . Sites of insertion that destroyed the methotrexate resistance fell in two regions separated by 300 bp within a 1.2 kb fragment . One of these regions encodes a 78 amino acid polypeptide homologous to another drug-resistant DHFR . The second region essential for DHFR expression appears to be the promoter of the DHFR gene. Mol Gen Genet, 1981, 181(4), 417 - 9 Three-factor reciprocal cross mapping of a gene that causes expression of feedback-resistant acetohydroxy acid synthase in Escherichia coli K-12; Jackson JH et al.; The ilv-662 allele was previously identified as a mutation that caused acetohydroxy acid synthase activity to be resistant to feedback inhibition by valine (Davis et al . 1977) . This allele was mapped between thr and leu by cotransduction analysis and labeled ilvJ . This report describes the mapping of ilvJ relative to genes that lie between thr and leu (ara, carA and pdxA) by three factor reciprocal cross analyses . We find that the probable gene order is thr-carA-pdxA-ilvJ-ara-leu . Although the phenotypic properties of ilvJ662 appear to be quite distinct from brnS, a gene reported to involve branched chain amino acid transport (Guardiola et al . 1974), we do not rule out possible allelism because of the uncertainty of the map position of brnS. J Urol (Paris), 1981, 87(4), 249 - 51 {Primary vesical pneumaturia in the absence of diabetes (author's transl)}; Lhez JM et al.; Vesical pneumaturia occurring in the absence of any glycosuric diabetes suggested a uro-digestive origin . The pathogenesis of primary pneumaturia, in the absence of diabetes, is discussed on the basis of experimental research . The aetiopathogenic mechanism of this primary pneumaturia remains obscure. J Immunol Methods, 1981, 41(1), 115 - 24 Application of the Farr assay to the analysis of antibodies specific for UV irradiated DNA; Strickland PT et al.; In order to determine the optimum conditions for reactivity in the ammonium sulphate precipitation (Farr) assay was have studied the DNA binding properties of two antibodies raised against ultraviolet single stranded DNA (UVssDNA) complexed with methylated bovine serum albumin . In general the buffer composition, pH, temperature, and ionic strength conditions described for binding to undamaged DNA were found to be appropriate for binding to UV-irradiated DNA . However, some differences in detail were noted which indicate the necessity for checking the physical conditions of binding of individual antibodies . Mouse monoclonal antibody and rabbit polyclonal antisera bound to UVssDNA very rapidly, even when DNA and ammonium sulphate were added simultaneously, whereas this procedure prevented binding of rabbit antisera to UV-irradiated double stranded DNA . Incubation at 45 degrees C for 30 min inhibited binding by mouse antibody, and incubation at 37 degrees C for 60 min caused reversible dissociation of the DNA-antibody complex . The optimised Farr assay was used to define the antigen specificities of the antibodies . The mouse antibody specifically bound to UVssDNA, but not to ssDNA, double stranded (ds) DNA, or UVdsDNA, whereas the rabbit antisera bound to UVssDNA, ssDNA or UVdsDNA, but not dsDNA . The extent of binding of the mouse antibody was dependent on the UV dose to the antigen, as well as the antigen concentration, indicating that the Farr assay can form the basis of a quantitative assay for photoproducts in DNA. Chromosoma, 1981, 82(4), 515 - 23 In situ transcription analysis of chromatin template activity of the S-chromosome of Drosophila following high molar NaCl treatment; Chatterjee RN et al.; The chromatin template activity of the polytene chromosomes in larval salivary glands of Drosophila hydei has been assayed by in situ transcription, on the fixed chromatin using E . coli RNA polymerase holoenzyme and 3H-UTP as the monitoring substrate, both with optimal salt and high salt concentration (1 M NaCl) . Results reveal an increase in the net transcription of all chromosomes in the high salt treatment series in comparison with the control . The X-chromosomes of the male larval gland also shows an increase in the labelling following the high salt treatment, but the increase is significantly less than that of the autosomes of the same nucleus . On the basis of these findings it has been suggested that the X-chromosomal hyperactivity of the male, as normally known to exist, might be guided by an inherent modulation of the structure of the X-chromatin. Annu Rev Biophys Bioeng, 1981, 10, 151 - 74 Applications of 13C NMR to metabolic studies; Scott AI et al.; It is our view that the above examples, most of which have been published in the last two years, represent the beginnings of a new field and that in spite of major problems in instrumentation and programming, the essential feasibility of using enriched 13C substrates for metabolic processes as a noninvasive technique has been firmly established . With the caveat that a rigorous protocol for signal assignment must be devised, we can look forward to many applications of this method in a wide range of biological systems. Acta Microbiol Acad Sci Hung, 1981, 28(2), 165 - 70 Guanosine polyphosphate production of Escherichia coli stringent and relaxed strains in the stationary phase of growth; Kramer M et al.; Stringent and relaxed Escherichia coli strains grown on minimal and on differently enriched media produced guanosine polyphosphates in the stationary phase of growth . On transition from the logarithmic to the stationary phase, stringent strains started to produce guanosine 5' triphosphate 3' diphosphate (pppGpp) . and guanosine 5' diphosphate 3' diphosphate (ppGpp), while relaxes strains accumulated only ppGpp . When the stringent strain was cultivated on media enriched with Casamino Acids the leve of pppGpp decreased, while with yeast extract an almost twofold increase could be observed . The concentration of ppGpp increased with both nutrients as compared to that measured in minimal medium . Readdition of glucose to the stationary phase culture did not result in the slightest decrease of the nucleoside polyphosphate levels . In contrast, addition of a mixture of 20 L-amino acids or Casamino Acids or yeast extract to the medium caused an abrupt decrease in the guanosine polyphosphate levels . Qualitatively similar results were obtained with the relaxed strains except that the amounts of ppGpp were smaller than in the case of the stringent counterpart and the responses to the resupplementation were slower . Some possible mechanisms regarding the occurrence of guanosine polyphosphates in the stationary phase are discussed. J Mol Evol, 1981, 17(2), 85 - 93 Evolutionary sequence divergence within repeated DNA families of higher plant genomes . II . Analysis of thermal denaturation; Preisler RS et al.; An assay based on derivative analysis of thermal denaturation (melting) behavior of reassociated DNA was developed in an attempt to characterize the sequence relationships in repeated DNA families according to the homogeneous or heterogeneous models of Bendich and Anderson (1977) . The validity of the technique was confirmed by the use of deaminated Escherichia coli DNA models for repetitive families . The melting data for DNA reassociated at two different temperatures provided strong evidence that Pisum sativum repeated families are mostly heterogeneous, while homogeneous families predominate in Vigna radiata . These findings, together with other differences between the two genomes, suggest that the rate of sequence amplification has been higher in the evolutionary history of Pisum DNA . A general trend seems to exist for high amplification rates in large, highly repetitive plant genomes such as Pisum and lower rates in smaller plant genomes such as Vigna, as well as in the generally smaller, less repetitive genomes of most animal species. Genetika, 1981, 17(5), 782 - 93 {Mutation affecting the promotor region of the Escherichia coli K-12 deo-operon}; Akhliustina EV et al.; It was shown that the strain SA1030 (Das et al., 1976) contains a mutation (deoPx), which decreases deoR regulated expression of the deo operon . Thymine dependent strain harbouring deoPx mutation decreases requirement in thymine up to 8-10 microgram/ml . The deoPx mutation causes 9 fold and 3 fold decrease in the activity of thymidine phosphorylase and purine nucleoside phosphorylase, respectively in cytR-deoR- strains, i.e . under the conditions of maximal derepression of the operon . The presence of cya mutation in deoPx background causes reduction of the activity of both enzymes to basal level, no matter whether cytR or deoR repressor proteins are present or not . It is supposed that deoPx mutation blocks the activity of the deoP promoter, while the cytP promoter remains unchanged . On the other hand, the deoR mutation gives rise to a rather high level of the activity of deo enzymes in cya+cytR+ strains harbouring deoPx mutation, as compared to those found in the corresponding deoR+ strains . These data may be explained by the conception that two repressor proteins function in a cooperation with respect to repression of the deo-genes (Hammer-Jespersen, Munch-Petersen, 1975) . The deoPx mutation is cotransducible (approximately 50%) with the thr gene and is located near the deo operon to the left of dra, indicating the order of markers on the chromosome to be deoPx--dra--thr . In transduction and conjugation matings deoPx mutation is characterized by a very low frequence or the absence of integration into the chromosomes of some recipient strains . These data, suggest that deoPx mutation is the result of a rearrangement of genetic material in the promoter region of the deo operon. Chemotherapy, 1981, 27(4), 264 - 9 Effects of doxycycline on the phagocytosis of 32 P-labelled Escherichia coli by human polymorphonuclear cells; Melby K et al.; A study on the effect of various concentrations (2-100 microgram/ml) of doxycycline on the phagocytic activity of human polymorphonuclear cells was undertaken using a radio-labelled strain of Escherichia coli as test particle . In the presence of 10% normal human serum pretreatment with 50-100 microgram/ml resulted in a 50% increase in cell-associated radioactivity . When omitting serum during the ingestion phase, or conducting the ingestion phase at 4 degree C, the ingestive capability was reduced . 2 microgram/ml present during the ingestion together with 10% normal human serum reduced the ingestive capability significantly, whereas the presence of 10 microgram/ml exerted no significant effect . By the use of 3H-labelled doxycycline the drug was shown to be firmly fixed to the leukocyte monolayer. Biokhimiia, 1981 Jan, 46(1), 92 - 9 {Influence of alcohol lipotropic agents on biosynthesis and repression of secreted alkaline phosphatase in Escherichia coli}; Zemlianukhina OA et al.; Preincubation of cells in the presence of 4% ethanol accompanied by an increase of non-saturated cis-vaccenic acid content was shown to promote synthesis of alkaline phosphatase . Preincubation of cells in 0.1% hexanol reducing the level of this acid, on the contrary, leads to partial repression of the enzyme synthesis; the lag-phase of repression in the cells with a raised content of non-saturated cis-vaccenic acid and, consequently, with a greater fluidity of lipids was also shown to be reduced . Conversely, the reduction of lipid membrane fluidity on ethanol addition simultaneously with the repressing metabolite ortho-phosphate extends the lag-phase of repression and removes it partially during cell cultivation in the presence of ortho-phosphate . The impact of lipid composition variations on the synthesis and repression of alkaline phosphatase is discussed. Res Vet Sci, 1981 Jan, 30(1), 57 - 61 The influence of Escherichia coli O78 endotoxin on carbohydrate metabolism in the domestic fowl; Curtis MJ et al.; The injection of endotoxin isolated from a pathogenic avian strain of Escherichia coli (1 mg/kg intravenously) accelerated the depletion of liver glycogen in fasting nine- to 10-week-old chickens within the first hour and concurrently reduced their plasma inorganic phosphate levels . These changes were attributed to increased glycogenolysis and were followed by hypoglycaemia and a large increase in the lactate content of the plasma which appeared to be caused by enhanced glucose oxidation and reduced gluconeogenesis . The plasma glucose level returned to normal within three hours and simultaneous changes in the plasma urate and albumin content indicated that glucose was being synthesised from amino acids and that albumin was being catabolised to provide them. Proc Natl Acad Sci U S A, 1981 Jan, 78(1), 243 - 6 Nucleotide sequence of cloned rat serum albumin messenger RNA; Sargent TD et al.; The nucleotide sequences of the recombinant DNA inserts of three bacterial plasmid clones containing nearly all of the rat serum albumin mRNA have been determined . A statistical analysis of the nucleotide sequence reveals a pattern of repeated internal homology that confirms the "intragenic triplication" model of albumin evolution. Proc Natl Acad Sci U S A, 1981 Jan, 78(1), 215 - 9 Membrane potential changes during the first steps of coliphage infection; Labedan B et al.; Immediately after adsorption, phages T4 and T5 induce a partial depolarization of the host cytoplasmic membrane . Infected bacteria respond to this phage-induced effect by a repolarization that leads to a new steady state of reduced membrane potential . The rate and extent of repolarization are adjusted to the intensity of depolarization, which depends on the number of adsorbed phages . Consequently, the new steady state membrane potential is attained in the same interval of time regardless of the maximum depolarization . These membrane potential changes appear to be independent of phage-specific properties (type of phage, presence of DNA and internal proteins, injection process) and of several membrane-related parameters (temperature, external pH, preinfectious level of membrane potential) . We propose that phage adsorption to the outer membrane triggers the emission of a signal that is transmitted to the cytoplasmic membrane . Additivity of independent signals is possible when stimuli (phages) are added at the same time . Additional adsorption of phages has no further depolarizing effect as soon as the repolarization begins . We propose that this refractoriness to secondary depolarization nd the shut-off of the first depolarization are induced by the same chemical modification also initiated by adsorption of the first phage. Proc Natl Acad Sci U S A, 1981 Jan, 78(1), 138 - 42 Prophage (phi 80) induction in Escherichia coli K-12 by specific deoxyoligonucleotides; Irbe RM et al.; A cell preparation that is permeable to proteins and oligonucleotides yet produces infectious phage particles after induction treatments was obtained by plasmolysis of Escherichia coli cells lysogenic for phi 80 . When the permeabilized cells were exposed to specific oligo(deoxynucleotides), prophage (phi 80) was induced during further incubation . Of the dinucleotides tested, only d(A-G), d(G-G), and d(I-G) induced prophage . The essential base sequence of the deoxydinucleotides for the induction was determined to be deoxy(purine-G) . Among oligo(deoxynucleotides) with unique base composition examined, only oligo(deoxyguanylates) exhibited the inducing activity . Although this specific oligo(deoxynucleotide)-triggered induction occurred in recB- cells, the induction was not detected in recA- cells or in the cells lysogenic for induction-negative phi 80(ind-) . Possible biological significance of the oligo(deoxynucleotide)-triggered prophage induction is discussed. Mol Gen Genet, 1981, 181(3), 411 - 3 Chromosome replication following a temporary inhibition of DNA-synthesis by nalidixic acid in a temperature-sensitive dnaA mutant of Escherichia coli; Khachatourians GG; Chromosome replication cycle in a DNA initiation mutant of Escherichia coli (CRT-83, dnaAts) was blocked by nalidixic acid, an inhibitor of the A subunit of DNA gyrase . Following a period of inhibition of DNA synthesis, the drug was removed and "run-out" DNA synthesis was examined . It was found that the "capacity" for DNA synthesis was not affected by such a treatment. Mol Gen Genet, 1981, 181(3), 356 - 62 Organization of genes in the four minute region of the Escherichia coli chromosome: evidence that rpsB and tsf are co-transcribed; Bendiak DS et al.; Restriction endonuclease-generated DNA fragments of lambda polC-9 (Friesen et al . 1976) have been cloned on plasmid vehicles . Expression of genes carried by these plasmids was determined either by genetic complementation of the appropriate mutants, or in ultraviolet-irradiated cells . On the basis of these experiments we have inferred the following gene order in the four minute region of the Escherichia coli chromosome: tonA-dapD4-dapD2-rpsB-tsf-22 kilodalton protein - fir 27,000-firA-dnaE . We suggest that rpsB and tsf are in one transcriptional unit, with rpsB being promoter-proximal . We also suggest the possible position of the promoter for dnaE. Int Arch Allergy Appl Immunol, 1981, 65(3), 300 - 3 Studies on the K antibody response in rabbits immunized with a pool of five different K antigen-containing Escherichia coli; Kaijser B; The Escherichia coli K antibody response in rabbits which were immunized with a mixture of E . coli O1K1H7, O6K2a2cH1, O4K12, O6K13H1 and O6K53, or with only one of these strains, was analyzed using indirect hemagglutination . Some K antigens gave generally high antibody response, while others did not . There were not statistically significant difference concerning K antibody response for each of the K antigens when the rabbits were immunized with one strain or a mixture of strains . The information is important for the composition of a future E . coli vaccine containing several K antigens. Gene, 1981 Jan-Feb, 13(1), 1 - 12 Variants of a cloned synthetic lactose operator . I . A palindromic dimer lactose operator derived from one stand of the cloned 40-base pair operator; Betz JL et al.; Starting with one strand of the 40-bp synthetic operator (Sadler et al., 1978), we have constructed and cloned a 66-bp, palindromic DNA segment with the following sequence (Formula: see text), where the horizontal arrows indicate the locations of the two 21-bp "core" operator sequences in this segment and the vertical arrow designates the dyad axis of symmetry . Upon denaturation and rapid renaturation, each strand of this fragment forms a hairpin molecule still retaining an EcoRI cohesive end . Two hairpin molecules can be joined with T4 DNA ligase to form a duplex DNA molecule having no ends (dumbbell form A) . Denaturation and rapid renaturation of dumbbell A yields a mixture of two dumbbell forms: dumbbell A which is a substrate for Eco RI, and a new form, dumbbell B, which is not a substrate . Each of the conformations of this DNA fragment have been purified and all are active in binding lactose repressor in vitro. Adv Biophys, 1981, 14, 1 - 35 Subunit of assembly of Escherichia coli RNA polymerase; Ishihama A; The isolated subunits of Escherichia coli DNA-dependent RNA polymerase are reassembled in a stepwise manner in the following sequence: 2 alpha leads to alpha 2 leads to alpha 2 beta leads to alpha 2 beta beta' (premature core enzyme) leads to E (active core enzyme) . When the in vitro reconstitution is performed at low temperature, the subunit assembly is prevented until the assembled but inactive premature core enzyme is formed, which is similar to native core enzyme in many parameters of gross conformation but differs from it in several minor and local conformations . The temperature-dependent activation of premature core enzyme at a salt concentration as low as that in vivo takes place only in the continuous presence of either the sigma subunit or DNA . The sigma subunit is therefore proposed to be a regulatory protein which influences the conformation of core subunit assembly in multiple ways from the initial enzyme maturation to the final initiation of transcription . Evidence has accumulated which indicates that the subunit assembly in vivo proceeds via the same pathway as that identified in vitro, including the identification of all species of the assembly intermediates in cell extracts, the identification of all possible types of assembly-defective mutants among temperature-sensitive alpha-, beta-, and beta'-subunit mutants, the kinetics of the appearance of pulse-labeled subunits in the enzyme structure as expected from the assembly sequence and the integration of labeled subassemblies into the enzyme structure upon chasing . The functional complexity of RNA polymerase coupled with transcriptional control appears to depend on its structural flexibility which fluctuates through the assembly with various transcription factors . This type of transcriptional control is being thoroughly considered by a final conclusion awaits further examinations. Poult Sci, 1981 Jan, 60(1), 49 - 53 Genetic and phenotypic correlations between immune response to Escherichia coli and to Newcastle disease virus vaccines; Soller M et al.; Genetic and phenotypic variation and covariation in immune response to inactivated Newcastle disease virus (NDV) vaccine and to Escherichia coli vaccine were studied in commercial poultry strains . Within any given experiment there was no tendency for individual birds to respond in a correlated manner to NDV and E . coli vaccines . There were highly significant differences between sire families in immune response to NDV vaccine (57 sire families) and to E . coli vaccine (35 sire families) . Heritabilities of immune response levels to NDV and to E . coli were .41 and .25, respectively . In both cases, additive genetic standard deviations were slightly over 1.0 titer unit . The correlation between sire-family means for response to NDV and sire-family means for response to E . coli (35 sire families) was .077 and statistically nonsignificant . Thus, the data provide evidence for the presence of significant genetic variation in immune response with respect to two endemic disease antigens, but they provide no evidence for a genetic correlation in response to the two antigens. Genetika, 1981, 17(2), 258 - 67 {Genetic study of the mutations impairing guanine, xanthine and hypoxanthines assimilation in a purine auxotroph of Escherichia coli K-12}; Brikun IA et al.; The hpt gene is responsible for the synthesis of hypoxanthine-guanine phosphoribosiltransferase . This gene was located between aceE and pan markers on the linkage map of Escherichia coli K-12 by a detailed transductional analysis using P1 phage . As described earlier by Nijkamp and De Haan, the guaC mutation blocks the synthesis of guanosine-5'-monophosphate reductase . The cotransduction frequencies of guaC with leu, azi, nadC, aceE, hpt and pan showed the guaC site to be positioned anterior to nadC marker . The order of these genes appeared to be as follows: leu--azi--guaC--nadC--aceE--hpt--pan. Genetika, 1981, 17(2), 246 - 57 {Phenotypic manifestation of the pnd mutation, which promotes purine nucleoside cleavage by Escherichia coli K-12 cells, in the genome of strains defective in the metabolism of nucleic acid precursors}; Kocharian ShM et al.; Strains of Escherichia coli K-12 containing both pnd1 mutation, rendering bacteria capable to catabolize purine nucleosides without participation of purine nucleoside phosphorylase (pup gene), and mutations in several genes of purine metabolism or nucleosides catabolism have been constructed . The introduction of the deletion mutation in adenosine deaminase gene (add) into the pup pnd genome does not affect the ability of mutants to utilize adenosine and deoxyadenosine as the sole carbon and energy sources . Mutations affecting purine phosphoribosyltransferases (hpt and gpt) block the ability of pup pnd mutants to utilize hypoxanthine, guanine and their deoxyribonucleosides and also xanthine and xanthosine as the only purine source . A mutation in deoxyribomutase (drm) disturbs the ability of pnd mutants to use all purine ribo- and deoxy-ribonucleosides as carbon and energy sources, whereas a mutation in deoxyriboaldolase (dra) only disturbs utilization of deoxyribonucleosides . These data seem to indicate that the activity promoted by pnd mutations catalyzes the cell reaction of irreversible phosphorolytic cleavage of the N-glycoside bond of the purine nucleosides molecules: purine nucleoside + phosphate leads to purine + pentose-1-phosphate . It is suggested that pnd mutations affect the structural gene of some phosphorolytic enzyme and modify its substrate specificity . Evidence is presented that the structural gene of a new nucleoside phosphorylase is not sensitive to catabolite repression. Appl Environ Microbiol, 1981 Jan, 41(1), 46 - 50 Cadmium-binding component in Escherichia coli during accommodation to low levels of this ion; Khazaeli MB et al.; An inducible cadmium-binding protein was isolated from Escherichia coli cells accommodated to 3 X 10(-6) M Cd2+ but not from normal or unaccommodated cells . Sephadex G-100, metal chelate affinity chromatography, and disc gel electrophoresis were used in the purification procedure . The molecular weight of the Cd2+-binding protein was estimated to be about 39,000 by Sephadex G-100 chromatography, making it different from the conventional, much smaller metallothionein. Zentralbl Bakteriol Naturwiss, 1981, 136(1), 3 - 9 Protein composition of Bdellovibrio bacteriovorus and Escherichia coli membranes during their interaction; Severin AI et al.; A comparative study of membrane proteins of Bdellovibrio bacteriovorus and host-bacteria Escherichia coli was performed by polyacrylamide gel electrophoresis in presence of sodium dodecyl sulphate . Infection of E . coli cells by bdellovibrions resulted in the loss of some high-molecular proteins and appearance of new ones in the host-bacteria membranes . The possible role of parasite proteases in degradation of host-bacteria membrane proteins is discussed. Mol Gen Genet, 1981, 181(1), 24 - 8 Conditional lethality of Escherichia coli strains carrying dnaE and dnaQ mutations; Horiuchi T et al.; A double mutant of Escherichia coli K12 which carries a conditional lethal mutator mutation, dnaQ49 (Horiuchi et al . 1978), and a DNA polymerase III-deficient mutation, dnaE486 (Wechsler and Gross 1971), was found to be more thermolabile than was either of the dnaQ49 or dnaE486 single mutants . The double mutant is able to grow at 28 degrees C but not at 30 degrees C . Under the restrictive conditions DNA synthesis, but not protein synthesis, of the double mutant was suppressed . All the other combinations of dnaQ and dnaE mutation alleles tested so far rendered the cells thermolabile . A dnaZ mutation exerted a similar effect on the dnaQ strain . However, when non-specific temperature-sensitive growth mutations were combined with the dnaQ49 mutation, no such increase in thermosensitivity was observed . There is a possibility that the product of the dnaQ gene interacts directly with the DNA replicating enzyme complex. Mol Gen Genet, 1981, 181(1), 101 - 6 The influence of colicinogenic plasmids ColIb-P9, ColIa-CA53 and ColV-K30 on the repair, mutagenesis and induction of colicin E1 synthesis; Khmel IA et al.; The presence of colicinogenic plasmids ColIb-P9 and ColIa-CA53 in E . coli K-12 cells, wild-type with respect to repair, enhanced the survival of cells after UV irradiation and increased the frequency of UV-induced argE3 and his-4 reversions, while the presence of ColV-K30 negatively affected repair and mutagenesis . The plasmid ColIb-P9 showed a UV-protective effect in E . coli cells carrying mutations in genes uvrA, uvrB, uvrC, polA, recB, recF, though in none of the mutants did cell survival reach the wild-type level . The effect of ColIb-P9 on mutagenesis did not depend on the uvrA or recB genes . The plasmid's protective effect and the enhancement of mutagenesis depended on the recA+ lexA+ genotype . The frequency of 2-aminopurine-induced mutations was not affected by ColIb-P9 or ColV-K30 . The presence of ColIb-P9 decreased the ability of ColE1-carrying cells to induce colicin E1 synthesis caused by DNA-damaging agents: UV, MNNG, mitomycin C, whereas ColV-K30 increased the percentage of colicin E1-producing cells . These plasmid effects on the level of induction of colicin E1 synthesis were not observed in the case of induction caused by chloramphenicol which did not depend on the products of recA and lexA genes. J Clin Lab Immunol, 1981 Jan, 5(1), 47 - 51 Age dependence of subpopulations and functions of human peripheral lymphocytes; Birkeland SA; The eventual dependency of a series of immune parameters on age has been studied in a material of 288 normal persons, divided into 2 sexes and with 16 persons in each 5-year age interval between 5 and 95 years, using a cryobiological freezing and storage system for lymphocytes with subsequent testing in large series . Lymphocyte transformation responses were studied after stimulation with a series of mitogens and specific antigens (PHA, PWM, PPD, Con A, SA, EC, CA and SK/SD), as well as with allogene cells in mixed lymphocyte culture . Values were found to decrease with increasing age . No age-dependency could be demonstrated for T and B lymphocytes using rosette formation tests . There was no difference between the two sexes . Thus, increasing age does not change the distribution between T and B lymphocytes, but does lead to a decrease in the function of the cell-mediated response. Int Arch Allergy Appl Immunol, 1981, 65(1), 102 - 6 Immediate hypersensitivity in the guinea pig conjunctiva . III . long-term persistence of the hypersensitive state and characterization of antibodies; Dwyer RS et al.; The ocular immediate hypersensitivity reaction in guinea pigs to topically applied normal rabbit serum can be evoked as long as 4 years after sensitization . The reaction was as severe and tended to persist for longer than that evoked 6 months after sensitization . Passive cutaneous anaphylaxis tests showed that very high titres of homocytotropic antibodies were present and that both IgE- and IgG1-like antibodies were involved . Sensitization with one set of injections instead of two was not consistently successful and the response on challenge was mild to moderate . Pretreatment of eyes with Isoptocarpine before antigenic challenge had no effect on the response . The addition of bacterial lipopolysaccharide to the first set of sensitizing injections produced hypersensitivity in animals which were otherwise refractory to sensitization. Infect Immun, 1981 Jan, 31(1), 500 - 3 Production of heat-labile or heat-stable enterotoxins by strains of Escherichia coli belonging to serogroups O44, O114, and O128; Scotland SM et al.; Strains of Escherichia coli which belong to enteropathogenic serogroups usually fail to produce heat-labile or heat-stable enterotoxins . However, 1 of 34 strains of E . coli O44, 9 of 45 strains of E . coli O114, and 18 of 82 strains of E . coli O128 produced heat-labile or heat-stable enterotoxins . Most enterotoxigenic isolates were from tropical or developing countries; all three enterotoxigenic strains isolated in Britain were from patients returned from abroad . Enterotoxigenic strains were of many different flagellar types . Certain enterotoxigenic strains of E . coli O114 and O128 possessed colonization factor antigen I. Infect Immun, 1981 Jan, 31(1), 42 - 51 K88-mediated binding of Escherichia coli outer membrane fragments to porcine intestinal epithelial cell brush borders; Middeldorp JM et al.; We have examined the interactions between various radiolabeled membrane fractions obtained from an enterotoxigenic Escherichia coli strain and brush borders isolated from porcine intestinal epithelial cells . Outer membrane fragments containing the K88 attachment factor bound tightly to brush borders, whereas cytoplasmic membrane vesicles did not . Three different types of outer membrane preparations were tested: (i) cellular outer membranes isolated from lysozyme spheroplasts, (ii) medium vesicles or outer membrane fragments released into the medium during growth, and (iii) periplasmic vesicles, or outer membrane fragments which were released from the cells during spheroplast formation and were therefore isolated in the periplasmic fraction . Of these fractions, which were heterogeneous, it was always the outer membrane subfraction which bound tightly to brush borders . This binding, which was K88 dependent, may have some physiological significance in view of the association between outer membrane fragments and enterotoxin . Thus, released outer membrane fragments equipped with attachment factors may function as enterotoxin carriers which increase the efficiency with which enterotoxin can be delivered to intestinal epithelial cells. Infect Immun, 1981 Jan, 31(1), 252 - 60 Respective contributions to protection of primary and booster immunization with Escherichia coli heat-labile enterotoxin in rats; Klipstein FA et al.; The respective contributions to protection of the route and dosage of primary and booster immunizations with Escherichia coli heat-labile enterotoxin were evaluated in rats . The degree of protection was determined by challenge with toxin and viable bacteria in ligated ileal loops, and the serum antitoxin response was assayed by enzyme-linked immunosorbent assay . Primary immunization was effective only when given by the parenteral route . The degree of protection was enhanced a fivefold dosage increase in the primary parenteral immunization in rats given constant dosages of booster immunizations either parenterally or perorally, but not by further dosage increases . In contrast, the degree of protection rose when dosages of the booster immunizations were increased over a 25-fold range . Four weekly peroral, but only two biweekly parenteral, booster immunizations were necessary to achieve strong protection; biweekly combined parenteral and peroral booster immunizations yielded both strong, immediate and extended protection . The degree of protection against the toxin correlated with that against viable bacteria and with elevated serum antitoxin titers: all seven groups with a protection index of greater than 5 against the toxin had strong protection against heat-labile toxin-producing strains and fourfold or greater increases in the antitoxin titers, whereas none of the nine groups with a protection index of less than 3 was protected against bacteria or had an equivalent antitoxin response . These observations show that once an adequate parenteral primary immunization is given, the degree of protection is influenced primarily by the dosage of the booster immunizations, the necessary number of which is dependent on their route of administration. Infect Immun, 1981 Jan, 31(1), 245 - 51 Comparison of enterotoxic activities of heat-stable enterotoxins from class 1 and class 2 Escherichia coli of swine origin; Whipp SC et al.; Pig small intestine develops age-dependent resistance to some (class 2 strains) enterotoxigenic Escherichia coli while remaining susceptible to others (class 1 strains) . This study tested the hypothesis that class 1 and class 2 strains produce different subtypes of heat-stable enterotoxin (ST) . The dose-response curves of small intestine to crude ST preparations from a class 1 and a class 2 strain were compared in several species . In infant mice, the class 1 ST preparation was less active than the class 2 ST preparation, whereas in rabbits the preparations were equally potent . However, in 1-, 7-, and 14-week-old pigs, the class 1 ST preparation was more active than the class 2 preparation . At low doses, both preparations caused reduced absorption in pigs of all three age groups, and at high doses the class 1 preparation caused secretion in all three age groups . In contrast, at high doses the class 2 preparation caused secretion in 1-week-old pigs but only reduced absorption in older pigs . when class 1 and class 2 ST preparations were fractionated by methanol extraction, in both cases the mouse-negative, pig-positive activity was associated with the methanol-insoluble fraction and mouse-positive, pig-positive activity was associated with the methanol-soluble fraction . The results are consistent with a hypothesis that class 1 and class 2 strains of enterotoxigenic E . coli produce different subtypes of ST and that the response of pig intestine to ST varies with both age and toxin subtype. Eur J Biochem, 1981, 114(1), 127 - 31 Decrease in the S1 protein of 30-S ribosomal subunits in polyamine-requiring mutants of Escherichia coli grown in the absence of polyamines; Igarashi K et al.; The reason for the decrease of polypeptide-synthetic activity of 30-S ribosomal subunits obtained from two polyamine-requiring mutants of Escherichia coli, grown in the absence of polyamines, has been studied by analyzing the total and split proteins of 30-S subunits by disc gel and slab gel electrophoresis . It was concluded that the decrease of S1 protein in 30-S subunits was responsible for the decrease of polypeptide synthesis in polyamine-requiring mutants of E . coli grown in the absence of polyamines. Eur J Biochem, 1981 Jan, 113(3), 563 - 8 {Structure of the heptose region of the lipopolysaccharide from Escherichia coli K12 CR34 (author's transl)}; Blache D et al.; The heptose region of the lipopolysaccharide of Escherichia coli K12 CR34 was studied . The glucose linked to the heptose II was found to be substituted by a D-galactose and the linear chain of the core polysaccharide has two (1 lead to 3) linked heptoses . The heptose II is substituted by a lateral (1 leads to 7) linked heptose III and heptose I is linked in (1 leads to 5) to 2-deoxy-D-manno-octulosonic acid . The three sugars of the linear chain, heptose I, heptose II and glucose are substituted by phosphate, pyrophosphate or pyrophosphorylethanolamine group linked to C-4 hydroxyl groups . However, in some polysaccharidic chains one or two substituting groups may be absent . This result may explain the heterogeneity in the length of the core polysaccharidic chains. Eur J Biochem, 1981 Jan, 113(3), 555 - 61 Succinic semialdehyde dehydrogenases of Escherichia coli: their role in the degradation of p-hydroxyphenylacetate and gamma-aminobutyrate; Donnelly MI et al.; Two physically and genetically distinct forms of succinic-semialdehyde dehydrogenase have been identified in Escherichia coli B . The two enzymes could be separated by filtration on Sephadex G-150 and their apparent molecular weights were 200 000 and 97 000 . The larger enzyme, which is specific for NADP, is induced by growth on gamma-aminobutyrate . Its induction is highly coordinated with that of gamma-aminobutyrate:2-oxoglutarate transaminase, the enzyme which initiates degradation of gamma-aminobutyrate . The smaller enzyme, which is induced by growth on p-hydroxyphenylacetate, has been purified to 98% homogeneity by affinity chromatography in conjunction with conventional methods . Under standard assay conditions this enzyme acts preferentially with NAD but reduces NADP at 15% of the rate observed for NAD, primarily because of a difference in Km . Apparent Km values for succinic semialdehyde and NAD are 13.3 +/- 1.3 microM and 33.7 +/- 1.4 microM, respectively . The subunit molecular weight was estimated to be 55 000, indicating that the native enzyme is dimeric . The NAD-dependent succinic-semialdehyde dehydrogenase is also induced by exposure of cells to exogenous succinic semialdehyde, a treatment which has no effect on the amount of other enzymes of p-hydroxyphenylacetate or gamma-aminobutyrate metabolism . Apparently the gene for this enzyme functions independently from the genes encoding the other enzymes of p-hydroxyphenyl-acetate degradation . As a consequence of its induction mechanism, this NAD-dependent dehydrogenase is also present in extracts of E . coli B grown with gamma-aminobutyrate as sole nitrogen source, in addition to the NADP-specific enzyme involved in gamma-aminobutyrate metabolism . Presumably the NAD-dependent enzyme is gratuitously induced by succinic semialdehyde formed by transamination of gamma-aminobutyrate. Cell, 1981 Jan, 23(1), 79 - 88 Suppressor mutations that restore export of a protein with a defective signal sequence; Emr SD et al.; A selection procedure is described that should allow the genetic identification of cellular components involved in the process of protein localization in Escherichia coli . This procedure makes use of mutations that alter the signal sequence of the lambda receptor protein (product of the lamB gene), and prevent export of this protein to its normal outer membrane location . Several suppressor mutations have been identified that restore export of the mutant lambda receptor protein . Mapping experiments show that the suppressor phenotype is the result of mutations in any of at least three different chromosomal loci . One class of suppressor mutations, the class containing the largest number of independent isolates, maps in the major ribosomal gene cluster, suggesting that the suppressor phenotype is the consequence of an altered ribosomal protein . This class of suppressors phenotypically suppresses all known export-defective mutations, internal to the signal sequence region of the lamB gene . These results suggest that ribosomes play an important role in the export of lambda receptor to the outer membrane. Cell, 1981 Jan, 23(1), 229 - 38 Incompatibility properties of Col E1 and pMB1 derivative plasmids: random replication of multicopy replicons; Hashimoto-Gotoh T et al.; The incompatibility properties of Col E1-like plasmids have been examined in Rec+ and RecA- bacteria . Two Col E1- (or two pMB1-) derivative plasmids coreplicated in the same clone for many cell doublings, irrespective of the rec genotype of host bacteria . Their kinetics of segregation were found to be consistent with models that assume a random choice of template molecule for each plasmid replication event, but with models based on a single (master) template molecule per cell . In contrast, minimal coreplication of a Col E1- and a pMB1-derivative plasmid occurred, with the latter type rapidly excluding the former . We suggest here that the pMB1 derivatives, pMB9 and pBR322, are less sensitive than Col E1 derivatives to the putative inhibitor that regulates plasmid replication, due to base sequence differences in their target for the inhibitor, and consider one mechanism whereby the duplication of Col E1-like plasmids might be regulated. Can J Microbiol, 1981 Jan, 27(1), 81 - 6 Type I nitroreductases of Escherichia coli; Bryant DW et al.; Analysis of partially purified crude extract of Escherichia coli K12 by chromatography and gel electrophoresis has resulted in the separation of three distinct activities which catalyse the reduction of nitrofurazone (semicarbazone of 5-nitro-2-furaldehyde) in the presence of oxygen (type I nitroreductases) . The major enzymatic activity (type IA), which was dependent solely on NADPH as a cofactor, was absent from nitrofurazone-resistant strains NFR 402 and NFR 502, but present in SIL 41, a strain which is only marginally resistant to the nitrofuran . The remaining nitroreductase activities (IB1 and IB2) utilize either NADH or NADPH as a cofactor . These activities coelute from DEAE-cellulose at pH 7.2, but may be differentiated by their behaviour on CM-cellulose at pH 5.8 . The reductase activity missing in SIL 41 was observed in extracts of strain NFR 402 but not NFR 502 . This enzyme (IB1) though retained by DEAE-cellulose had no affinity for CM-cellulose . The only reductase present in extracts of NFR 502 (a nitrofuran-resistant strain selected after two mutational events) was type IB2 . This activity, also detectable in SIL 41 and NFR 402, has not been mapped genetically . An interesting feature of the type IB2 enzyme is its apparent inactivation by MnCl2 which has been routinely used as a partial purification step in the past. Can J Microbiol, 1981 Jan, 27(1), 147 - 9 The Anderson--Baird-Parker direct plating method versus the most probable number procedure for enumerating Escherichia coli in meats; Rayman MK et al.; Comparison of the Anderson--Baird-Parker direct plating method (DP) and the North American most probable number procedure (MPN) for enumerating Escherichia coli in frozen meats revealed that the DP method is more precise and yields higher counts of E . coli than the MPN procedure . Any of three brands of membrane filters tested was suitable for use in the DP method. Arkh Patol, 1981, 43(1), 12 - 7 {Early changes in the kidney microcirculatory bed in the generalized Sanarelli-Shwartzman reaction}; Val'kovich EI et al.; Investigations of early changes of renal microcirculation in generalized Sanarelli-Schwartzmann's reaction revealed markedly manifest alterations in endotheliocytes, podocytes, basal membrane of the glomeruli accompanied by disorders in the permeability of their capillaries and disseminated microthrombosis. Mutat Res, 1981 Jan, 80(1), 15 - 25 The effects of lexA101, recB21, recF143 and uvrD3 mutations on liquid-holding recovery in ultraviolet-irradiated Escherichia coli K12 recA56; Tang MS et al.; Using an Escherichia coli K12 recA strain, we have tested the effects of incorporating additional mutations affecting deoxyribonucleic acid (DNA) repair on ultraviolet-radiation sensitivity and on the expression of liquid-holding recovery (LHR) . (This laboratory had previously shown that a mutation at uvrA, uvrB or uvrC blocked LHR in a recA strain.) In the recA56 background, an additional lexA101 mutation had no effect on UV-radiation sensitivity or LHR . The addition of a recB21 mutation to recA56 did not alter UV-radiation sensitivity, but greatly increased the rate of LHR . The recB gene product (exonuclease V) appears to act as a competitive inhibitor both of excision repair and of photoreactivation under liquid-holding (LH) conditions . The uvrD3 mutation increased the radiation sensitivity of a recA strain, and almost completely blocked LHR . The recA uvrD strain showed more DNA degradation and DNA double-strand breaks during LH than did the recA strain . The recF143 mutation increased both UV-radiation sensitivity and LHR in a recA strain, suggesting that the recF gene product may also function in recA-independent pathways of DNA repair. J Appl Physiol, 1981 Jan, 50(1), 185 - 90 Effect of methysergide on the acute lung mechanics response to endotoxin; Allison RC et al.; The effect of the serotonin antagonist methysergide on the acute lung mechanics response to endotoxin in anesthetized, paralyzed, mechanically ventilated dogs was investigated . In five dogs given 0.25 mg/kg Escherichia coli endotoxin only, the pulmonary nonelastic resistance (RL) increased to 238% of control and dynamic compliance (CL) decreased to 50% of control . In a second group of five dogs, methysergide (0.25 mg/kg) was shown to markedly attenuate the lung mechanics response to serotonin (0.04 mg/kg), which alone had produced changes in lung mechanics greater than endotoxin . In these same dogs endotoxin administered after injection of methysergide produced an increase in RL to 377% and a decrease in CL to 33% of control . In a third group of five dogs whose lung mechanics response to serotonin was also greater than to endotoxin alone, endotoxin administered after injection of saline produced an increase in RL to 168% and a decrease in CL to 58% of control . Since the response to endotoxin after injection of methysergide exceeded the response after saline, we conclude that serotonin is not a mediator of the acute lung mechanics response to endotoxin. J Appl Physiol, 1981 Jan, 50(1), 178 - 84 Role of platelet serotonin in the canine pulmonary response to endotoxin; Murphy TL et al.; There is evidence suggesting a role for platelet serotonin (5-HT) in the immediate pulmonary response to endotoxin in the dog (J . Appl . Physiol . 23: 47, 1967) . To further define this role, autologous canine platelets were labeled with 5-{14C}HT in vitro and then reinfused . Subsequently Escherichia coli endotoxin (0.55:B-5, Difco), 2.5 mg/kg, was injected . Within 5 min dynamic compliance (CL) fell by more than 50%, and nonelastic resistance (RL) increased by more than 200% . Despite a 95% decrease in platelet count, less than 10% of the platelet 5-HT was released as determined by changes in the radioactivity of platelet-poor plasma (PPP) prepared from both aortic and pulmonary artery blood . As a positive control, injected of bovine collagen produced a similar decrease in platelet count that was associated with a significant increase in the radioactivity of aortic and pulmonary artery PPP . FInally, rapid injection of a dose of 5-HT equivalent to 25% of the 5-HT in circulating platelets did not cause a change in CL or RL equivalent to that produced by endotoxin . From these data we conclude that endotoxin injection does not cause immediate massive platelet activation and that platelet 5-HT does not play a major role in the immediate pulmonary response to endotoxin. Eur J Biochem, 1981 Jan, 113(2), 375 - 80 Precursor proteins are intermediates in vivo in the synthesis of two major outer membrane proteins, the OmpA and OmpF proteins, of Escherichia coli K12; Crowlesmith I et al.; The OmpA and OmpF proteins are major outer membrane proteins of Escherichia coli K12 . Their precursors, the pro-OmpA and pro-OmpF proteins, have been detected in vivo in pulse-labelling experiments carried out with {35S}methionine at 25 degrees C . Wehn the pulse was at 37 degrees C, however, no precursors were detected . The pulse-labelled precursors were processed rapidly and quantitatively into mature protein at 25 degrees C . The apparent half-life of the pro-OmpF protein was estimated to be 30 s, and the pro-OmpA protein may be processed even faster . In short pulses (10 s) the precursors of both proteins were the predominant labelled species, indicating that at 25 degrees C processing does not start until chain elongation of the precursor is almost, if not entirely, complete . When French press lysates of cells pulse-labelled for 10 s were subjected to sucrose gradient centrifugation to separate the inner and outer membranes, both precursors comigrated with the inner membrane. Eur J Biochem, 1981 Jan, 113(2), 349 - 57 Identification of different forms of the murein-bound lipoprotein found in isolated outer membranes of Escherichia coli; Wensink J et al.; The identification of the free and murein-bound forms of the Escherichia coli lipoprotein on dodecylsulphate-polyacrylamide gels was systematically investigated by analyzing the low-molecular-weight proteins (Mr less than 20 000) of both cytoplasmic and outer membranes . The free form of the lipoprotein was identified on 15% polyacrylamide gels as the fastest migrating component (Mr = 7200-7500) of isolated outer membranes; it could be separated from a small cytoplasmic membrane protein (Mr = 6500) which was probably identical to the dicyclohexylcarbodiimide binding proteolipid of the membrane-bound ATPase . Lysozyme treatment of both outer membranes and murein sacculi failed to convert the murein-bound lipoprotein into a fragment of uniform size; instead the bound form appeared as a series of bands consisting of lipoprotein bound to one, two,...eight murein subunits . The composition of this ladder depended on the method used to isolate outer membranes . Beside these lipoprotein bands the outer membrane contained two other proteins, III and V; the relation of these proteins to previously described proteins is discussed. J Clin Microbiol, 1981 Jan, 13(1), 49 - 53 Properties of binding of Escherichia coli endotoxin to various matrices; Maitra SK et al.; Binding of Escherichia coli O127:B8 endotoxin to a variety of resins and column materials was investigated by measuring the beta-hydroxy myristic acid content (a major component of the lipid A moiety) of endotoxin after hydrolysis by selected ion-monitoring gas chromatography-mass spectrometry . More than 80% of the endotoxin was bound to hydroxylapatite, polystyrene, Dowex 1-X2, and charcoal . The binding of endotoxin to these materials was markedly reduced by the addition of normal or delipidated serum . Phenyl- and octyl-Sepharose bound 56 and 50% of the endotoxin from saline solutions, respectively . Their percent binding was increased significantly in 1 M ammonium sulfate solutions, indicating hydrophobic interactions between endotoxin and phenyl- and octyl-Sepharose . Only 5% of the endotoxin was bound to plastic polymer PSI-HAP-100 beads, and no binding was observed with concanavalin A- and heparin-Sepharose . Study of the in vitro binding of endotoxin to the above material in the presence of serum suggests that the use of these materials in removing circulating endotoxin in vivo is limited. J Clin Microbiol, 1981 Jan, 13(1), 179 - 83 Toxin detection after storage or cultivation of enterotoxigenic with colicinogenic Escherichia coli: a possible mechanism for toxin-negative pools; Murray BE et al.; Of 100 non-enterotoxigenic Escherichia coli isolated from children with diarrhea in Bangkok, Thailand, 24 were found to produce colicin(s) . Of these, 87% were active against one or more enterotoxigenic E . coli isolated from the same population . Storage of nine enterotoxigenic E . coli with known inhibitory colicin-producing E . coli in different proportions caused 51 of 96 pools to become negative in the suckling mouse assay (heat-stable toxin) and 17 of 52 to become negative in the Y-1 adrenal cell assay (heat-labile toxin) . Cocultivation of the same strains, without prior storage, caused 12 of 96 pools to become negative for heat-stable toxin and 1 of 52 pools to become negative for heat-labile toxin . Storage or cultivation of E . coli in pools may cause negative results in the suckling mouse and Y-1 adrenal cell assays if any of the isolates in the pool produces colicin(s). J Clin Microbiol, 1981 Jan, 13(1), 139 - 46 Validation of Legionella pneumophila indirect immunofluorescence assay with epidemic sera; Wilkinson HW et al.; Sera from six outbreaks of legionellosis and four outbreaks of pneumonia of other etiologies were tested with the indirect immunofluorescence assay (IFA) as currently performed . The current IFA is at least as sensitive as the original test in detecting cases of Legionnaires disease (78 to 91%) . By using Center for Disease Control criteria for a positive (fourfold increase in titer during convalescence to greater than or equal to 128) or presumptive (single titer greater than or equal to 256) serological test, the specificity exceeded 99% . No cross-reactions against Legionella pneumophila antigens were observed among sera from epidemic cases of Q fever, tularemia, and psittacosis; the only positive L . pneumophila IFA titer among the epidemic Mycoplasma pneumonia sera was reduced to a negative titer with an immunosorbent extracted from Escherichia coli strain O13:K92:H4 . The slight increase in specificity (to 100%), however, was offset by a slight decrease in sensitivity . The sensitivity of the IFA was maximal when a conjugate that detected immunoglobulins G, M, and A was used . IFA titers were not significantly altered by replacing the monovalent serogroup 1 antigen with a polyvalent antigen (serogroups 1 through 4) nor by the presence of rheumatoid factor or heat-labile serum factors. J Bacteriol, 1981 Jan, 145(1), 88 - 96 Regulatory mutations conferring constitutive synthesis of major outer membrane proteins (OmpC and OmpF) in Escherichia coli; Sato T et al.; An ompB strain of Escherichia coli K-12 lacking major outer membrane proteins OmpC and OmpF was used to isolate a pair of mutants that have restored the ability to synthesize either OmpC or OmpF protein . These mutants were found to produce the respective proteins constitutively under the several conditions where the synthesis in the wild-type strain was markedly repressed; namely, in the absence of the ompB gene function, under restrictive medium conditions, or upon lysogenization with phage PA-2 . The mutations ompCp1 and ompFp9 responsible for such synthesis were shown to be located in the close vicinity of the corresponding structural genes, ompC and ompF . Moreover, the mutations affect the expression of these genes in a cis-dominant fashion . Taken together with other evidence, it was suggested that ompCp1 and ompFp9 represent regulatory site mutations occurring at the promoter regions of ompC and ompF respectively . Relevance of these findings to the genetic control of outer membrane protein synthesis is discussed. J Bacteriol, 1981 Jan, 145(1), 668 - 71 Cleavage of colicin Ia by the Escherichia coli K-12 outer membrane is not mediated by the colicin Ia receptor; Bowles LK et al.; Colicin Ia can be cleaved by isolated outer membranes prepared from sensitive and resistant (lacking the colicin Ia receptor) strains of Escherichia coli . Both active and heat-denatured colicin Ia are extensively fragmented . Such proteolysis does not occur when colicin Ia is added to whole sensitive or resistant cells . These results demonstrate that cleavage of colicin Ia is not mediated by its outer membrane receptor. J Bacteriol, 1981 Jan, 145(1), 647 - 50 Use of cir-lac operon fusions to study transcriptional regulation of the colicin Ia receptor in Escherichia coli K-12; Worsham PL et al.; We describe cir-lac operon fusions constructed by using phage Mu d(Apr lac) . Expression of beta-galactosidase in these fusion strains is analogous to known regulatory properties of cir gene expression . It is concluded that the observed regulation by iron of the cir gene is under transcriptional control. J Bacteriol, 1981 Jan, 145(1), 644 - 6 Escherichia coli K-12 clones that overproduce dam methylase are hypermutable; Herman GE et al.; A strain of Escherichia coli K-12 that overproduces dam methylase 50-fold was found to be hypermutable, and mutations which resulted in loss of excess methylase activity restored mutation frequencies to wild-type levels . These results are consistent with involvement of this deoxyribonucleic acid methylase in mismatch correction. J Bacteriol, 1981 Jan, 145(1), 472 - 8 Lipid synthesis during the Escherichia coli cell cycle; Carty CE et al.; Lipid synthesis was examined in Escherichia coli cells at different stage of cell division . Exponentially growing cells were pulse-labeled with appropriate isotopes for 0.1 generation time, inactivated, and separated by size on a sucrose gradient . An abrupt increase in the rate of lipid synthesis occurred which was coincident with the initiation of cross walls . In contrast, the rate of protein synthesis during this same interval remained constant, resulting in an increased lipid/protein ratio in dividing cells . No changes in the composition of phospholipid head groups, fatty acids, or phospholipid molecular species were observed in cells at different stages of division . The observed increase in the rate of lipid synthesis may reflect a means by which the activities of membrane-associated enzymes are modulated during cross wall formation. J Bacteriol, 1981 Jan, 145(1), 459 - 65 High-efficiency, temperature-sensitive suppression of amber mutations in Escherichia coli; Zengel JM et al.; We have constructed a high-copy-number plasmid carrying an allele of the supD gene (supD43,74) . The plasmid conferred temperature-sensitive suppression of amber mutations . Strains carrying the plasmid exhibited 50 to 60% suppression at 30 degrees C but little or no suppression at 42 degrees C . After a temperature shift from 30 to 42 degrees C the efficiency of suppression decreased gradually over a 60- to 90-min period before reaching the 42 degrees C steady-state level of suppression. J Bacteriol, 1981 Jan, 145(1), 43 - 9 Methyl-accepting chemotaxis protein III and transducer gene trg; Hazelbauer GL et al.; A comparison of the two-dimensional gel patterns of methyl-3H- and 35S-labeled membrane proteins from trg+ and trg null mutant strains of Escherichia coli indicated that the product of trg is probably methyl-accepting chemotaxis protein III . Like the other known methyl-accepting chemotaxis proteins, the trg product is a membrane protein that migrates as more than one species in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, implying that it too is multiple methylated . It appears likely that all chemoreceptors are linked to the tumble regulator through a single class of membrane protein transducers which are methyl-accepting proteins . Three transducers are coded for by genes tsr, tar, and, probably, trg . Another methyl-accepting protein, which is not related to any of these genes, was observed. J Bacteriol, 1981 Jan, 145(1), 429 - 33 Role of peptide chain elongation factor G in guanosine 5'-diphosphate 3'-diphosphate synthesis; Pao CC et al.; In a wild-type strain (relA+) of Escherichia coli, starvation of amino acid led to an immediate cessation of the synthesis of stable ribonucleic acids, together with the accumulation of an unusual nucleotide, guanosine 5'-diphosphate 3'-diphosphate, commonly known as ppGpp . This compound also accumulated during heat shock . When temperature-sensitive protein synthesis elongation factor G (EF-G) was introduced into E . coli NF859, a relA+ strain, the synthesis of ppGpp was reduced to approximately one-half that of wild-type EF-G+ cells at a nonpermissive temperature of 40 degrees C . Furthermore, fusidic acid, an inhibitor of protein synthesis which specifically inactivates EF-G, prevented any accumulation of ppGpp during the heat shock . We suggest that a functional EF-G protein is necessary for ppGpp accumulation under temperature shift conditions, possibly by mediating changes in the function of another protein, the relA gene product . However, EF-G is probably not required for the synthesis of ppGpp during the stringent response, since its inactivation did not prevent ppGpp accumulation during amino acid starvation. J Bacteriol, 1981 Jan, 145(1), 35 - 42 Multiple forms of methyl-accepting chemotaxis proteins distinguished by a factor in addition to multiple methylation; Hazelbauer GL et al.; Methyl-accepting chemotaxis proteins are central to both the excitation and adaptation phases of chemotactic behavior . Using null mutations in the genes coding for the two major methyl-accepting proteins (tsr and tar), we identified the gene products among the membrane proteins of Escherichia coli visualized on one- and two-dimensional gels . On two-dimensional gels, both the tsr and the tar proteins appeared as a group of multiple spots arranged in two to four diagonal arrays . The multiplicity of forms could not be completely explained by the previously documented heterogeneity of the methylated proteins resulting from different numbers of methylated glutamyl residues per polypeptide chain . We suggest that there is at least one other way besides extent of methylation in which the polypeptides of a methylated protein can differ. J Bacteriol, 1981 Jan, 145(1), 341 - 7 Increased binding of a hydrophobic, photolabile probe to Escherichia coli inversely correlates to membrane potential but not adenosine 5'-triphosphate levels; Wolf MK et al.; We describe conditions for a quantitative determination of azidopyrene binding to Escherichia coli cells . In addition, we define conditions whereby irradiation of azidopyrene in the presence of cells leads to irreversible association of probe with cells . This is presumably due to the light-dependent generation of reactive nitrenes and subsequent incorporation of nitrenopyrene moieties into cellular components . These methods allowed us to determine that the amount of azidopyrene bound to cells was inversely correlated with the magnitude of the cellular membrane potential, but was not correlated with high or low adenosine 5-triphosphate levels per se . Cells bound more azidopyrene if the delta psi was low . Cell-bound azidopyrene was found to be entirely associated with the inner and outer membrane . We suggest that the decreased association of hydrophobic probes upon energization of whole cells reflects a rapid transition in structural properties of the cell envelope. J Bacteriol, 1981 Jan, 145(1), 293 - 8 Use of gene fusions to determine the orientation of gene phoA on the Escherichia coli chromosome; Sarthy A et al.; We present genetic evidence which demonstrates that the phoA gene is transcribed in the clockwise direction on the Escherichia coli chromosome, in contrast to an earlier proposal . Our conclusion is based on analysis of various genetic fusions between the lac operon and the phoA gene. J Bacteriol, 1981 Jan, 145(1), 211 - 20 Regulation of hexuronate system genes in Escherichia coli K-12: multiple regulation of the uxu operon by exuR and uxuR gene products; Robert-Baudouy J et al.; New regulatory mutants of Escherichia coli K-1 carrying alterations of the uxuR gene were isolated and characterized . In the presence of superrepressed or derepressed uxuR mutations, mannonic hydrolyase (uxuA) and oxidoreductase relationship analyses suggested that the uxuR gene product acted as a repressor in the control of uxuA-uxuB operon expression . uxuR mutations were localized near min 97, and the following gene order was established: (argH)-uxuR-uxuB-uxuA-(thr) . Properties of exuR (point and deletion) mutants showed that both exuR and uxuR regulatory gene products were involved in the control of the uxuA uxuB operon . Analysis of exuR uxuR double-derepressed mutants suggested that exuR and uxuR repressors act cooperatively to repress the uxu operon. J Bacteriol, 1981 Jan, 145(1), 113 - 21 Two interacting mutations causing temperature-sensitive phosphatidylglycerol synthesis in Escherichia coli membranes; Nishijima M et al.; A conditionally lethal mutant of Escherichia coli lacking phosphatidylglycerol in vivo at 42 degrees C has been previously isolated by two-stage mutagenesis (M . Nishijima and C . R . H . Raetz, J . Biol . Chem . 254:7837-7844, 1979) . In the first step (designated pgsA444) the phosphatidylglycerophosphate synthetase is partially inactivated, but the resulting strain continues to make about two-thirds of the normal level of phosphatidylglycerol and is not temperature sensitive . The second lesion, termed pgsB1, causes temperature-sensitive growth and phosphatidylglycerol synthesis in strains harboring pgsA444 . The pgsA locus appears to be the structural gene for the synthetase and maps near min 42 . In the present study we mapped the pgsB1 mutation and characterized its interaction with pgsA444 by genetic and biochemical methods . Unexpectedly, pgsB1 was not a second lesion in the pgsA structural gene, but rather mapped at a distinct site near minute 4 . P1 vir-mediated contransduction suggested the gene order pantonA-dapD-pgsB-dnaE (clockwise) . Independent evidence for the genetic mapping was provided by the identification of two hybrid ColE1 plasmids (pLC26-43 and pLC34-20 . L . Clarke and J . Carbon, Cell 9:91-99, 1976) which both carry pgsB+ and dnaE+ . Introduction of either the pgsA+ or the pgsB+ gene (via episomes, hybrid plasmids or P1 vir transduction) suppressed the temperature sensitivity of the double mutant (pgsA444 pgsB1) and restored normal levels of phosphatidylglycerol at 42 degrees C . In addition, strains with the pgsA+ pgsB1 genotype produced a novel lipid (X) at all temperatures, whereas the double mutant (pgsA444 pgsB1) contained two unusual lipids (X and Y) after 3 h at 42 degrees C . Both X and Y are precursors of lipopolysaccharide, and introduction of pgsB+ into the double mutant caused the disappearance of X and Y . Although the biochemical basis of the pgsB1 lesion is unknown, its existence suggests a previously unrecognized link between lipopolysaccharide and phosphatidylglycerol syntheses in E . coli. Endocrinology, 1981 Jan, 108(1), 353 - 6 Hybridization histochemistry: use of recombinant DNA as a "homing probe" for tissue localization of specific mRNA populations; Hudson P et al.; A procedure, termed hybridization histochemistry, has been developed to locate in specially prepared whole sections of tissue those areas which contain specific mRNA populations . Three 32P-labelled recombinant DNA probes were used; one complementary to endorphin mRNA, one complementary to growth hormone mRNA and one a fragment of bacterial DNA . The specific cell populations or tissue regions binding the probe were identified by autoradiography . Hybridization histochemistry is thus similar in principle to immunohistochemical procedures . The endorphin probe consistently labelled the rat pituitary pars intermedia which is known to be particularly rich in the corresponding mRNA . Likewise the growth hormone probe specifically labelled the anterior pituitary . Control tissues were not labelled by either probe, nor did the bacterial DNA probe significantly label any tissue, providing further evidence of the specificity of the procedure . These results, which are highly reproducible, indicate that the mRNA species for endorphin and growth hormone are present in whole sections of pituitary in a physical state which leaves them accessible to cDNA probes . This initial success provides encouragement that hybridization histochemistry, with further refinement, should have wide applicability in the localization and semi-quantitative analysis of intracellular mRNA in whole frozen sections of tissue. Br J Surg, 1981 Jan, 68(1), 55 - 8 Alanine metabolism in patients with chronic infection; Royle GT et al.; Alanine matabolism was studied in surgical patients with chronic infection and non-infected control subjects by means of an intravenous infusion of alanine . Septic patients had low basal blood concentrations of alanine compared with control subjects but alanine half-life was similar in both groups . This suggests that low basal alanine concentration in the septic patients was due to decreased release from muscle rather than increased hepatic uptake . Alanine infusion in septic patients caused a fall in the blood concentration of ketone bodies which was initially raised . Similar increases in blood concentrations of glucose, lactate, pyruvate an insulin occurred in both septic and control patients after alanine infusion . Hyperketonaemia may limit muscle breakdown and alanine release in patients with chronic infection. Am Rev Respir Dis, 1981 Jan, 123(1), 79 - 84 Emphysema associated with intravascular leukocyte sequestration . Comparison with papain-induced emphysema; Guenter CA et al.; The pulmonary effects of endotoxin-induced, repetitive, intravascular leukocyte sequestration were studied in dogs and were compared to the effects of intratracheal papain . Lung specimens from 7 animals receiving 20 to 23 weekly injections were histologically and physiologically similar to those from 10 control animals . Dogs receiving 50 injections of endotoxin during 17 wk developed histologic evidence of emphysema as seen on whole lung sections, a significant increase in mean linear intercept, and loss of elasticity at high lung volumes . The group of animals given intratracheal papain also developed histologic evidence of emphysema, with increased mean linear intercepts and loss of lung elasticity . However, the effects on lung elasticity were much greater in the papain group . Endotoxin-induced, repetitive leukocyte sequestration in the lungs results in mild emphysema; however, similar changes in alveolar size appear to cause less effect on the pressure-volume loop than does papain-induced emphysema. South Med J, 1981 Jan, 74(1), 71 - 3 Hepatic abscess resulting from asymptomatic diverticulitis of the sigmoid colon; Liebert CW Jr; I have described a case of pyogenic liver abscess secondary to completely asymptomatic diverticulitis . Because extensive diverticulitis may be present with minimal or no clinical symptoms, it should be strongly considered as the cause when dealing with a so-called "cryptogenic" liver abscess, and treatment should be planned accordingly. Mol Gen Genet, 1981, 183(1), 175 - 80 Mutations affecting translational fidelity in the eucaryote Podospora anserina: characterization of two ribosomal restrictive mutations; Picard-Bennoun M; Fifty-nine mutations that restrict suppressor efficiency were selected in the fungus Podospora anserina using four different screening methods . Previous genetic analysis has shown that these antisuppressors lie in six loci and that they could be similar to ribosomal restrictive mutations known in Escherichia coli . The present study deals with the response of two of them, AS1-1 and AS6-1, to paromomycin and low temperature both in vivo and in vitro . The data demonstrate that ribosomes of the mutant and double-mutant strains are equally resistant to the ambiguity effect of paromomycin . These data are the first demonstration of mutations that increase translational fidelity in eucaryotic organism. Mol Gen Genet, 1981, 182(3), 505 - 7 Structure and properties of the region of homology between plasmids pMB1 and ColE1; Bhagwat AS et al.; Physical maps of the two independently isolated Escherichia coli plasmids, pMB1 and ColE1, were prepared with 13 restriction endonucleases and compared . A 5.1 kilobase continuous region covering 55% of pMB1 and 75% of colE1 was found to have similar, but non-identical, restriction maps . The differences in the maps of this region probably arose by localized mutational events rather than by major sequence rearrangements . The F-factor was found to mobilize pMB1 efficiently for conjugal transfer . A region on pMB1 required for its F-mediated transfer was mapped . Results of our study combined with results of other investigators suggest that pMB1 and ColE1 share functional properties such as colicin production, colicin immunity, mode of replication, and mobilization by the F-factor, and that the sequences required to code these functions are contained within the 5.1 kilobase homologous region. Aust N Z J Med, 1981, 11(Suppl 1), 109 - 11 IgA, glomerulonephritis and liver disease; Woodroffe AJ; Data from our Unit suggest that soluble immune complexes (IC) are responsible for the mesangial deposits of IgA and C3 in patients with IgA nephropathy . These IC are of intermediate size (9-17S) and contain IgA, IgG and less commonly IgM . Ubiquitous exogenous antigens have been implicated in some patients and primary defects in antigen exclusion or reticuloendothelial sequestration have been proposed to account for the formation and persistence of IC . The liver plays a central role in the clearance of antigens, polymeric IgA and IC, and liver disease is associated with alimentary hyperimmunization, hypergammaglobulinaemia (including IgA polymers) and circulating IC . At autopsy, mesangial (14/28), skin (10/18) and choroid plexus . (2/3) deposits of IgA were found in patients with alcoholic cirrhosis compared with 1/15, 3/10 and 2/5 respectively in controls . Raised serum antibodies to E . coli and to BSA were noted in patients with alcoholic cirrhosis but no specific antibodies have been detected in the kidney eluates . Circulating IC and mesangial deposits of IgA and C3 have also been demonstrated in rats with carbon tetrachloride-induced cirrhosis and after portacaval shunting . Measurement of reticuloendothelial function and the clearance of IgA polymers and IC is now required in patients with primary IgA nephropathy and HSP . In the meantime, IgA nephropathy is best regarded as a syndrome with primary and secondary forms, and as a clinical spectrum from isolated glomerulonephritis to systemic IC disease (HSP). Mol Gen Genet, 1981, 181(3), 352 - 5 Transcription of colicin E1 plasmid: electron-microscopic mapping of promoters; Naumova GN et al.; The promoters of ColE1 plasmid DNA have been localized . Their position has been determined relative to the functional map of the plasmid . The direction of transcription from each promoter has been established . Superhelical ColE1 DNA was transcribed in vitro by Escherichia coli RNA polymerase . The resulting complexes of DNA with nascent RNA were treated with restriction endonucleases EcoR1 and SmaI and observed in an electron microscope . Statistical analysis of RNA distribution on DNA made it possible to localize the promoters and determine the direction of transcription from them . The analysis was based on a specially prepared computer program. Toxicology, 1981, 21(2), 169 - 78 The effect of phospholipid-containing surfactant from nickel exposed rabbits on pulmonary macrophages in vitro; Wiernik A et al.; Alveolar macrophages from 9 normal rabbits were incubated in vitro for 3 h with and without phospholipid-containing surfactant from nickel-treated ones . The macrophages treated with surfactant showed morphological and functional criteria of increased activity . The cell surface had many protrusions and the cytoplasma contained several lamellated structures . The oxidative metabolism, measured by the nitroblue tetrazolium (NBT)-test, at rest and after E . coli stimulation was increased, as was the attachment and ingestion of yeast particles . The NBT-values were about the same as corresponding values of macrophages lavaged from the lungs of nickel-treated rabbit . Macrophages incubated with surfactant from untreated animals, had NBT values and phagocytic activity similar to cells incubated without surfactant . As this substance was administered in excess, the difference in macrophage response would probably be due to a qualitative alteration of the surfactant after nickel exposure. Adv Shock Res, 1981, 6, 163 - 74 The effect of compensation of acidosis on survival in endotoxin shock; Bastiaans JC et al.; IP injection of 10 mg E . coli endotoxin in fasted female rats causes 100% mortality while hemodynamic effects are absent . A progressive fall in blood glucose to extremely low values with a concomitant rise in plasma lactate is recorded . Plasma pH falls below 7.00 . Infusion of glucose or glucose and insulin does not prolong the survival time . An infusion of 5% NaHCO3 preventing the terminal acidosis has no effect on the survival time and dose not affect the blood glucose and plasma lactate concentrations . Artificial ventilation has no effect on survival time or on blood glucose and plasma lactate concentrations. Mol Gen Genet, 1981, 184(3), 355 - 8 Enhanced recombination between F42lac and lambda plac5: dependence on F42lac fertility functions; Porter RD; F42lac recombination with lambda plac5 is normally twentyfold to fiftyfold higher than recombination between lambda plac5 and a chromosomal lac gene . The presence of an fi+ R1 plasmid in the same cell as F42lac dramatically reduces this enhanced recombination level while the fi- R1drd19 plasmid has little effect . When F42lac traJ90 is tested in a sup+ strain, it shows a sharp reduction in recombination with lambda plac5 that can be largely reversed by the presence of a supF mutation that partially suppresses the traJ90 nonsense mutation . It is concluded that the enhanced recombination between F42lac and lambda plac5 is largely dependent on the constitutive expression of F42lac fertility functions. Mol Gen Genet, 1981, 183(3), 528 - 31 Codon binding and translational properties of an isoaccepting lysine tRNA peculiar to virus-transformed Cells; Bjercke RJ et al.; Isoaccepting lysyl-tRNAs from virus-transformed cells in culture were fractionated in the RPC-5 system into peaks 1, 2, 4, 5a, 5, and 6 . tRNALys6 previously was found predominantly associated with transformed cells . The codon response of each peak was determined in an E . coli ribosomal binding assay . tRNALys1, tRNALys2, and tRNALys4 are highly specific for the 5'AAG3' codon . tRNALys5 and tRNALys5a preferentially bind in response to AAA . tRNALys6 binds in response to AAA 3-fold better than in response to AAG . The presence of thiolated nucleosides in the anticodon regions of tRNALys5a, tRNALys5, and tRNALys6 is indicated by I2-inactivation of aminoacylation ability with no effect on the other is isoacceptors . Functional abilities of the isoacceptors were compared in a wheat germ translational system with tobacco mosaic virus RNA as messenger . All of the isoacceptors function about equally well in translation except for tRNALys6, which is only 14 to 24% as effective as the other isoacceptors. Mol Gen Genet, 1981, 183(1), 54 - 8 A mutation in the RNA polymerase beta' subunit causing depressed ribosomal RNA synthesis in Escherichia coli; Oostra BA et al.; Macromolecular synthesis in an Escherichia coli mutant with a temperature-sensitive beta' subunit of RNA polymerase was analysed . At the non-permissive temperature ribosomal RNA synthesis is strongly reduced while messenger RNA synthesis is affected to only a slightly extent . The overall protein synthesis is only slightly affected . We conclude that the beta' subunit is involved in promoter recognition and plays a role in transcriptional selectivity. Nucleic Acids Symp Ser, 1981, (9), 225 - 8 Cell-free expression of the beta-galactosidase gene: a model system to study the effects of nucleotide analogs on transcription-translation; Zimmer M et al.; A cell-free system for the expression of the beta-galactosidase gene was employed to study the effects of the UTP and CTP analogs: s2UTP, s2CTP, f5UTP and rTTP on transcription-translation . From the analogs investigated, only rTTP turned out to be able to substitute UTP in the cell-free synthesis of beta-galactosidase . In case of the other analogs listed above, the incorporation of even a small fraction of analog into rRNA resulted in drastic inhibition of beta-galactosidase synthesis. J Immunol Methods, 1981, 44(2), 125 - 33 A rapid solid-phase enzyme-linked binding assay for screening monoclonal antibodies to cell surface antigens; Cobbold SP et al.; A solid-phase enzyme-linked binding assay is described for screening monoclonal antibodies to cell surface antigens . E . coli beta-galactosidase was coupled to rabbit anti-rat Ig and used to detect the binding of rat monoclonal antibodies to cells which had been fixed to the wells of microtitre plates using a combination of poly-L-lysine and glutaraldehyde . This method was found to be advantageous for the large screening of monoclonal antibodies with a panel of cell types, and has been useful in the selection of antibodies which would be candidates for differentiation markers within the human and mouse haemopoietic systems. Folia Microbiol (Praha), 1981, 26(3), 212 - 6 A lipopolysaccharide from Aspergillus flavus conidia; Budinska O et al.; A lipopolysaccharide was isolated by extraction of Aspergillus flavus conidia with 45% phenol at 68-70 degrees C . Quantitative analysis revealed 7% nucleic acids, 5.5% proteins, 46% polysaccharides and 49% liquids, of which 12% were covalently bound . Glucose, mannose, galactose and fucose were detected as monosaccharide components of the polysaccharide moiety by gas chromatography; palmitic acid, stearic acid, oleic acid, linoleic acid and myristic acid were mainly present in the lipidic fraction . This material differs from the bacterial lipopolysaccharides, both in composition of the polysaccharide moiety and representation of fatty acids in the lipidic fraction. Chromosoma, 1981, 83(2), 199 - 208 Characterization of macronuclear DNA in five species of ciliates; Steinbruck G et al.; Macronuclear DNA of four hypotrichous and one holotrichous ciliate species was characterized by biochemical techniques . The renaturation kinetics of the macronuclear DNAs of all five species were similar . Repetitive sequences occur only in an amount below 2% . Although the DNA content of the macronuclei of the species differs considerably, the kinetic complexity of the macronuclear DNA is rather uniform (around 3 x 10(10) daltons, i.e., 4-11 x the E . coli genome) . Only in the macronuclei of the hypotrichous species the DNA exists as gene-sized fragments. Carcinogenesis, 1981, 2(6), 553 - 8 Minor products from the reaction of (+) and (-) benzo{a}-pyrene-anti-diolepoxide with DNA; Osborne MR et al.; The reaction of trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydrobenzo{a}pyrene (BP-diolepoxide) with deoxyguanosine has been studied . In addition to the expected N2-guanine derivative minor products resulting from reaction at the O6 and 7-positions have been identified . Reaction of racemic, (+) or (-) BP-diolepoxide with {14C} and {3H}purine labelled DNA allowed these same products to be identified and their yields estimated . It was found that the O6 and 7-guanine products were derived mainly from reaction of the (-)isomer . The 7-substituted guanine derivative in DNA was unstable, undergoing either spontaneous release of the substituted guanine or imidazole ring opening. Mol Gen Genet, 1981, 182(1), 137 - 42 Plasmid-mediated UV-protection in Myxococcus xanthus; McCann K et al.; Plasmid R46 was successfully transferred from Escherichia coli K=12 into myxococcus xanthus strain MD-1 but not into M . xanthus strain XK . Plasmid R68.45 was transferred from E . coli K-12 into both strains of M . xanthus . The effects of these plasmids on survival of M . xanthus after ultraviolet (UV)-244 nm irradiation, the ability of M . xanthus to reactivate irradiated myxophages, and weigle reactivation of UV-irradiated effect on UV survival of M . xanthus, but increased the host's ability to reactivation irradiated myxophages . Plasmid R68.45 protected M . xanthus strains MD-1 and XK against the lethal effects of UV irradiation and also increased the host's ability to reactivate irradiated myxophages. Mol Gen Genet, 1981, 181(4), 518 - 21 Promoter sites in the genome of B . subtilis phage SPP1; Stuber D et al.; Transcriptional complexes formed in vitro using DNA of B . subtilis phage SPP1 as template and E . coli and B . subtilis RNA polymerases were analyzed by electron microscopy . Both enzymes recognize the same five strong promoters in the early region of the genome . Strand selection at these sites was identical with both enzymes . These results correlate well with data obtained from in vivo transcription studies . Transcriptional activity in the late region of the genome was very low, not permitting the identification of promoter sites. Genetika, 1981, 17(5), 932 - 5 {Phenotypic properties of Escherichia coli K-12 purine auxotrophs with disordered synthesis of guanine, xanthine and hypoxanthine phosphoribosyltransferases}; Brikun IA et al.; Purine auxotrophs of Escherichia coli completely blocked for reutilization of guanine, xanthine and hypoxanthine via phosphoribosiltransferase reactions (purD hpt gpt) were studied . They lost the ability to utilize inosine as the source of carbon and purines though retained the purine nucleoside phosphorilase activity . The bacteria of this genotype were also found to be sensitive to leucine, despite the presence of relA+ allele . These phenotypic properties of the purD hpt gpt bacteria were suppressed by the introduction of cya mutation which affects cAMP synthesis into their genome . It has been shown that exogenous cAMP inhibits growth of purD hpt gpt (cya+) bacteria and this has been considered to suggest that purD hpt gpt cya bacteria have an increased pool of purine nucleotides as a consequence of a decrease in the catabolite-sensitive genes activity. Proc Natl Acad Sci U S A, 1981 Jan, 78(1), 464 - 8 Osmotic control of kdp operon expression in Escherichia coli; Laimins LA et al.; Turgor pressure, the difference in osmotic pressure across the inner membrane, has been found to regulate expression of the kdp operon in Escherichia coli . The kdp operon codes for a high-affinity repressible transport system for the uptake of potassium . We have studied the regulation of Kdp expression in a strain in which the gene for beta-galactosidase, lacZ, was placed under control of the kdp promotor . Neither internal nor external K+ concentrations directly controlled Kdp expression . Only when the external K+ concentration was reduced to the point of limiting growth was the kdp operon expressed . An increase in external osmolarity at constant K+ concentration, a procedure that reduces turgor pressure, caused expression of the kdp operon . As the magnitude of the osmotic shift was increased, corresponding to greater decreases in turgor pressure, the amount of Kdp expression also increased . The kdp operon thus appears to be controlled by changes in a physical force, the turgor pressure. Am J Vet Res, 1981 Jan, 42(1), 94 - 9 Therapeutic effect of phenylbutazone on experimental acute Escherichia coli endotoxemia in ponies; Burrows GE; Phenylbutazone (PBZ), a classic anti-inflammatory and prostaglandin-synthesis inhibitor drug, was used to determine the role of prostaglandins and other mediators on the development and perpetuation of the response to intraperitoneal Escherichia coli endotoxin administration . The PBZ (15 mg/kg of body weight) was administered IV 30 minutes after endotoxin administration and was repeated later at 6 and 12 hours at a dose of 10 mg/kg . A variety of evaluation measurements (hematologic, blood glucose, pyruvate, lactate and fibrinogen, serum beta-glucuronidase, prothrombin time, blood gases, hepatic glycogen, plasma esterase, capillary refill time, and rectal temperature) were utilized . Marked alterations were noted for all evaluators following endotoxin administration except for blood fibrinogen, prothrombin time, and plasma esterase activity . The PBZ therapy blocked the hemoconcentration, hyperglycemia, increased blood lactate, decreased bicarbonate, decreased blood pH, pyrexia, and prolonged capillary refill time responses associated with endotoxin administration . Despite the significant blocking effects of PBZ on endotoxin responses, the eventual survival rate was unaffected in these experiments. Acta Histochem Suppl, 1981, 23, 137 - 43 The nature of the intramembraneous particle; Verkleij AJ et al.; It is argued that the different modes of fracturing of the erythrocyte membrane and the outer membrane of Escherichia coli with respect to the intramembraneous particles have their definite biochemical and structural counterpart i.e., . the non-complementary particles of the erythrocyte membrane being predominantly proteinaceous in nature and the complementary particles of the outer membrane of E . coli being determined by lipopolysaccharide . Evaluation of the complementarity aspect of intramembraneous particles shows than an assessment of complementarity in replicas may decisive when interpreting micrographs at the macromolecular level. J Biochem (Tokyo), 1981 Jan, 89(1), 223 - 9 Enzyme immunoassay for antibodies in serum using a covalent chromatographic method for separation of the bound label; Yamamoto R et al.; A sensitive enzyme immunoassay system for the measurement of antibodies in serum was developed by the use of a separation method based on the thiol-disulfide interchange reaction . Serum samples including antibodies (anti-insulin, anti-human chorionic gonadotropin, or anti-beta-D-galactosidase) were incubated with antigens labeled with beta-D-galactosidase from Escherichia coli . Each reaction mixture was then passed through a small column (0.1 ml) of (anti-IgG)IgG-Sepharose 4B, in which the (anti-IgG)IgG had been coupled by means of a disulfide bond . The column was washed to remove the unbound label, then the antibody-bound label was eluted from the column with a buffer containing 25 mM dithiothreitol, which cleaved the disulfide bonds between the Sepharose matrix and the anti-IgG antibody molecules . By measuring the enzyme activity in the eluate, the amount of antibodies could be determined even in a serum sample which contained antibodies corresponding to as little as 0.01% of the standard antisera . Preliminary experiments showed that the present method can be used to detect the anti-insulin antibody in the sera from insulin-treated diabetic patients. J Clin Microbiol, 1981 Jan, 13(1), 1 - 5 Modified Elek test for detection of heat-labile enterotoxin of enterotoxigenic Escherichia coli; Honda T et al.; The Elek test was modified for detection of the heat-labile enterotoxin of enterotoxigenic Escherichia coli . A total of 164 strains of E . coli were tested by the modified Elek test, and the results correlated well with those of the Chinese hamster ovary cell assay and passive immune hemolysis . It is concluded that the modified Elek test is a simple and reproducible assay method for identification of E . coli which produce heat-labile enterotoxin, and is suitable for use in clinical laboratories. J Bacteriol, 1981 Jan, 145(1), 641 - 3 Mechanism of the rel defect in beta-galactosidase synthesis; Foley D et al.; Relaxed (relA) mutants of Escherichia coli are defective in beta-galactosidase synthesis during amino acid limitation . We show here that this defect comprises both a transcriptional component and a translational component. Int Arch Allergy Appl Immunol, 1981, 64(2), 190 - 4 Immune complexes and cryoproteins in ascitic fluid of patients with alcoholic liver disease; Quismorio FP Jr et al.; 27 paired specimens of ascitic fluid and serum obtained from patients with alcoholic liver disease were tested for cryoproteins and immune complexes by the C1q binding assay . 20 sera (74%) and ten ascitic fluid (37%) had significant amounts of cryoproteins . The cryoproteins were of the 'mixed' type of cryoglobulins consisting of IgG, IgM, IgA, C3 and C1q . The C1q binding test was positive in 17 sera (63%) and in 16 ascitic fluid (59%) . Intracytoplasmic inclusions of immunoglobulin and complement were found within the ascitic fluid leukocytes by direct immunofluorescence . The presence of immune complexes in the ascitic fluid may be important in the reduction of the complement level of cirrhotic ascitic fluid. Reprod Nutr Dev, 1981, 21(2), 177 - 83 {tRNA adaptation and the optimization of translation}; Garel JP et al.; The intracellular level of each tRNA species is adjusted to the codon frequency of the mRNA being decoded . This was first observed in such highly differentiated cells as the silk gland of Bombyx mori, which produces fibroin and sericin, and the rabbit reticulocyte . tRNA adaptation also occurs in other cell types from E . coli to mammalian cells . Regardless of the mechanism regulating tRNA biosynthesis, we believe that tRNA adaptation is the basic step optimizing chain elongation at the ribosomal level . We propose the system of trial and error as a working model for the ribosome . This model clarifies the correlations between iso-accepting tRNA levels and codon frequencies, as well as the effect of tRNA pool balance on mean elongation rate and non-uniform individual elongation rate (depending on whether codons are rare or abundant) for fibroin mRNA translated in a reticulocyte cell-free system. Mol Gen Genet, 1981, 184(3), 457 - 9 Lysogenic induction of lambdoid phages in lexA mutants of Escherichia coli; Sedgwick SG et al.; UV irradiation of lexA3 mutants of E . coli caused lysogenic induction of prophage lambda, lambda i21, lambda i434 and phi 80 . Maximal induction in lexA3 lysogens needed less UV than in lexA+ bacteria and gave 25-100% of the normal levels of infective centres induced . Assays of gene expression arising from derepression of a defective lambda prophage showed at least 40% of the normal levels of induction by mitomycin C in lexA3 bacteria . The need for post-irradiation protein synthesis for lysogenic induction in lexA3 lysogens was reduced by increasing the basal level of recA protein with a recA+ plasmid . It is concluded that in lexA E . coli some recA protein synthesis, too small to be detected by physical means, is needed for UV induced lysogenic induction. Mol Gen Genet, 1981, 184(1), 68 - 72 A temperature sensitive Reca protein of Escherichia coli; Hickson ID et al.; The temperature sensitive allele recA200 has been cloned into the multiple copy number plasmid pBR322 and the gene product isolated . The purified RecA200 protein is temperature sensitive in ability to cleave the phage lambda and LexA repressors in vitro and also in ability to promote a successful search for homology between single stranded DNA and a homologous duplex leading to D-loop formation . However, at the non-permissive temperature the RecA200 protein has approximately wild type single stranded DNA dependent ATPase activity and ability to promote pairing between homologous single DNA strands . The demonstration that the temperature sensitivity in vivo can be correlated with the temperature sensitive cleavage of the lambda and LexA repressors in vitro and also with D-loop formation shows that these in vitro reactions, which require large amounts of RecA protein, are not carried out by trace amounts of contaminating proteins. Mol Gen Genet, 1981, 183(3), 514 - 7 Negative regulation of beta and beta' synthesis by RNA polymerase; Lang-Yang H et al.; The genes for the beta and beta' subunits of RNA polymerase, rpoB and rpoC, and the genes for the two ribosomal proteins, rplL and rplJ, are part of the beta operon . Although this operon and contains a single strong promoter, the genes of the operon are not always coordinately expressed in vivo . This has now been confirmed in vitro where the lack of coordinate expression has been shown to be correlated with the selective inhibition of rpoB and rpoC gene expression by RNa polymerase . Rifampicin, which stops the initiation of transcription, also relieves this autogenous inhibition of beta and beta' (beta beta') synthesis . The inhibitory action of RNA polymerase and its reversal by rifampicin most likely occurs at a posttranscriptional or translation level. Mol Gen Genet, 1981, 183(3), 484 - 9 Rac-E . coli K12 strains carry a preferential attachment site for lambda rev; Diaz R et al.; Lambda rev is a hybrid lambdoid phage formed by recombination between lambda and a defective lambdoid prophage (Rac) present in most E . coli K12 derivatives . We show here that three independently derived Rac-E . coli K12 strains are specifically deleted for the entire Rac prophage consistent with loss of Rac by excisive recombination between hybrid attachment sites that flank the prophage (c.f . excision of a lambda prophage) . lambda rev, in which int and PP' of lambda have been replaced by integrative recombination genes and an attachment site derived from Rac (Gottesman et al . 1974), integrates site-specifically and in the correct orientation at the preferential attachment site generated by Rac excision. Mol Gen Genet, 1981, 183(3), 463 - 72 The genes for the eight subunits of the membrane bound ATP synthase of Escherichia coli; Hansen FG et al.; The genes for the eight subunits of the membrane bound ATP synthase of Escherichia coli (Ca++, Mg++ dependent ATPase, EC 3.6.1.3) were mapped through genetic, physical and functional analysis of specialized transducing phages lambda asn (von Meyenburg et al . 1978) . The ATP synthase genes, designated atp1, are located at 83.2 min in a segment of the chromosome between 3.5 and 11.3 kb left (counterclockwise) of the origin of replication oriC . The counterclockwise order of the genes for the eight subunits, the expression of which starts from a control region at 3.5 kb-L, was found to be: a, (c, b, delta), alpha, gamma, (epsilon, beta) which in the notation of Downie el al . (1981) reads atp B (EFH) A G (C D) . The analysis was in part based on the isolation of new types of atp (unc, Suc-) mutations . We made use of the fact that specialized transducing phages lambda asn carrying oriC can establish themselves as minichromosomes rendering asnA cells Asn+, and that the resulting Asn+ cells grow slowly if the lambda asn carries part or all of the atp operon . Selecting for fast growing strains mutations were isolated on the lambda asn which either eliminated atp genes or affected their expression ("promoter" mutations) . The relationship between these atp mutations and the cop mutations of Ogura et al . (1980), which also appear to map in front of or within the atp genes, is discussed. Mol Gen Genet, 1981, 183(3), 428 - 36 Identification of the protein products of the rrnC, ilv, rho region of the Escherichia coli K-12 chromosome; Gray JE et al.; Two methods have been used to identify the protein products of the Escherichia coli K-12 ilv region at 84 min and the flanking rrnC (counterclockwise) and rho (clockwise) loci . First, a set of lambda dilv specialized transducing phages, including some phages that carry rho and others that carry part of rrnC, was used to infect UV irradiated cells . The proteins produced by the infecting lambda dilv phage were selectively labelled with radioactivity amino acids and identified by SDS gel electrophoresis and autoradiography . Second, restriction enzyme fragments were cloned from the lambda dilv phage into pBR322 and the plasmid specific gene products produced in maxicells were similarly identified by SDS gel electrophoresis and autoradiography . The proteins produced were correlated with specific genes and restriction enzyme fragments present in the lambda dilv phage and the pBR322 derivatives . Several ilv gene products that have previously been refractory to protein purification attempts have been identified for the first time by this technique . The presence of mutations at the ilvO site is shown to activate the cryptic ilvG gene and to result in the production of a 62,000 dalton protein . A 15,000 dalton protein of unknown function is synthesized from a DNA segment between ilv and rrnC . The rho gene was cloned from lambda dilv phage into pBR322 and shown to be dominant to a rho mutation on the host chromosome . The rho gene product and four additional proteins coded by genes near or between rho and ilv have been detected. Mol Gen Genet, 1981, 184(2), 308 - 11 The influence of host DNA replicat