Mutat Res, 1983 May, 120(2-3), 91 - 5 Are econazole, miconazole and clotrimazole mutagenic to bacteria? Voogd CE, van der Stel JJ. The fungistatic drugs econazole, miconazole and clotrimazole were investigated as to mutagenic properties in the fluctuation test with Klebsiella pneumoniae and Escherichia coli K12 as test organisms and in the plate-incorporation test, with and without metabolic activation, with Salmonella typhimurium strains TA98 and TA100 . No mutagenic activity of the 3 compounds on these microorganisms was found. Mutat Res, 1983 May, 109(2), 183 - 93 The correlation between benzo{a}pyrene-induced mutagenicity and DNA adduct formation in Salmonella typhimurium TA100; Arce GT et al.; In an attempt to stabilize the dose response in the Salmonella typhimurium test (STT), the use of DNA-bound products from BP was evaluated as a measure of the biologically effective dose . In addition to the previously documented interlaboratory variation, we observed a 3-fold difference in the dose response of TA100 to BP even when the assay was repeated with the same experimental conditions . When overall BP-DNA adduct formation was related to the level of His+ revertants, a series of responses emerged with two predominating . In the first type of response around 70 revertants per plate were generated for every BP molecule bound per 10(6) nucleotides of cellular DNA . The second response gave about 1400 revertants per plate for one BP bound in every 10(6) nucleotides . Several intermediates curves were also detected . The variation in the mutational response to binding levels occurred regardless of the source of S9 or the growth stage of the cells . These experiments indicate that there was no constant level of DNA damage that would lead to a specified number of revertants of TA100 by BP and that DNA modification was not solely responsible for mutagenic potency . It is possible that an induction of an error-prone repair function of the muc gene carried by the plasmid pKM101 in TA100 may be affecting the relationship between the measured adduct level and reversion frequency. J Bacteriol, 1983 May, 154(2), 763 - 71 Isolation and characterization Salmonella typhimurium mutants lacking a tripeptidase (peptidase T); Strauch KL et al.; Salmonella typhimurium contains an enzyme, peptidase T, that hydrolyzes a variety of tripeptides . Specificity studies with a peptidase activity stain after gel electrophoresis of crude cell extracts showed that peptidase T hydrolyzes tripeptides containing N-terminal methionine, leucine, or phenylalanine . Little or no activity could be detected against dipeptides, N-blocked or C-blocked tripeptides, and tetrapeptides . Analysis of reaction products by high-pressure liquid chromatography showed that peptidase T removes the N-terminal amino acid from tripeptides . Mutants lacking peptidase T were isolated by screening microcultures grown in the wells of plastic microtitration plates for hydrolysis of Met-Ala-Ser or Met-Gly-Gly . Mutations (pepT) that eliminate this enzyme were found to be phage P22 cotransducible with purB at approximately 25 map units on the S . typhimurium map . Comparison of the growth properties of mutant and wild-type strains suggests that peptidase T does not function in utilization of tripeptides to provide amino acids during growth. Cancer Res, 1983 May, 43(5), 2052 - 8 Formation of DNA adducts in vitro and in Salmonella typhimurium upon metabolic reduction of the environmental mutagen 1-nitropyrene; Howard PC et al.; The polycyclic nitroaromatic hydrocarbon 1-nitropyrene is an environmental pollutant, a potent bacterial mutagen, and a carcinogen . Xanthine oxidase, a mammalian nitroreductase, catalyzed the in vitro metabolic activation of this compound to DNA-bound adducts . Maximum adduct formation occurred at pH 5.5 to 6.0 and was increased by the addition of catalase to the incubation medium . DNA binding from 1-nitropyrene was inhibited by hydrogen peroxide, L-ascorbate, and glutathione . Enzymatic hydrolysis of the modified DNA and subsequent analysis by high-pressure liquid chromatography indicated the presence of one major and two minor adducts . The major adduct was characterized by mass spectrometry and nuclear magnetic resonance spectroscopy as N-(deoxyguanosin-8-yl)-1-aminopyrene . The minor adducts appear to be decomposition products of the major adduct . When Salmonella typhimurium TA1538 was incubated with 1-nitropyrene, a strong correlation was found between the extent of DNA binding and the frequency of induced histidine reversions . Analysis of the bacterial DNA indicated one major adduct which had chromatographic properties and pKaS identical to those of N-(deoxyguanosin-8-yl)-1-aminopyrene . These data indicate that N-hydroxy-1-aminopyrene is probably the mutagenic and DNA-binding species formed during the metabolic reduction of 1-nitropyrene. J Bacteriol, 1983 May, 154(2), 561 - 8 Regulation of proline utilization in Salmonella typhimurium: characterization of put::Mu d(Ap, lac) operon fusions; Maloy SR et al.; The genes for proline utilization were fused to the structural genes of the lac operon by use of the hybrid Mu phage derivative Mu d(Ap lac) . Stable deletion derivatives of these fusions were selected and used to study the transcriptional regulation of the put genes . Analysis of these fusions showed that the putA gene product, a bifunctional oxidase-dehydrogenase, also serves to negatively control transcription of the putA and putP genes . Transcription of the put genes is repressed only in putA+ strains; this repression is lifted when exogenous proline is supplied . Transcription of the put genes is stimulated by cyclic AMP in putA+ and putA strains . Maximal induction of the put genes in putA+ strains requires oxygen or an alternative electron acceptor . This oxygen effect is mediated by the putA protein since putA mutants show maximal transcription even without an electron acceptor . The orientation of the Mu d(Ap lac) insertions was determined by formation of Hfr's via the lac homology on F'ts114 lac+ . The direction of chromosome mobilization by these Mu d(Ap lac)-directed Hfr's demonstrated that the putP and putA genes are divergently transcribed from a central regulatory region lying between them. J Mol Biol, 1983 Apr 15, 165(3), 443 - 59 DNA sequence changes of mutations in the histidine operon control region that decrease attenuation; Barnes WM et al.; The DNA sequence changes of 18 (9 different) mutations in the control region of the histidine operon of Salmonella typhimurium are presented . All of these mutations increase the level of expression of the operon, presumably by decreasing transcription termination at the attenuator . Five of the mutations were previously isolated hisO mutations, and the other four were isolated here as His+ pseudorevertants of His- stop codon mutations in the leader peptide gene . Only two mutations, O1242 and O3154, directly affect the terminator stem of the leader RNA . One mutation, O1202, creates a strong new stem that would compete with the terminator stem . Most of the other mutations damage other RNA stems . Their effect can best be explained by, and they thus provide supporting evidence for, the prevailing model of attenuator regulation involving alternative, competing RNA stems in the leader RNA . Two mutations that do not appear to significantly affect an RNA stem directly, including a deletion of three of the seven consecutive histidine codons, are best explained as effects of a translating ribosome upon the RNA stem structures, even though the histidine codons are not translated in the pseudorevertants. Science, 1983 Apr 8, 220(4593), 201 - 4 Fibronectin binds to some bacteria but does not promote their uptake by phagocytic cells; Van de Water L et al.; The involvement of plasma fibronectin in phagocytosis of bacteria was investigated by testing the binding of fibronectin to several species of bacteria and by evaluating the ability of fibronectin to promote binding and endocytosis of two species of these bacteria by phagocytic cells . Fibronectin binds non-covalently to Gram-positive and Gram-negative bacteria and to yeast but did not appear to be necessary or sufficient for uptake of Staphylococcus aureus and Salmonella typhimurium by several different phagocytic cell types. J Toxicol Environ Health, 1983 Apr-Jun, 11(4-6), 971 - 80 Detection of nitroaromatic compounds on coal combustion particles; Hanson RL et al.; Mutagenic and nonmutagenic extracts of fly ash from fluidized bed combustion were analyzed to determine the compounds responsible for the direct mutagenic activity (mutagenic activity that does not require added metabolic enzymes in the Salmonella mutagenicity assay) . Some nitro derivatives of polycyclic aromatic hydrocarbons which are direct acting mutagens were detected by tandem triple quadrupole mass spectrometry . Treatment of a mutagenic and a nonmutagenic extract with excess N2O4 resulted in 28- and 3200-fold increases, respectively, in direct mutagenicity in Salmonella typhimurium strain TA98 and an increase in the relative abundance of nitroaromatic compounds . Polycyclic aromatic compounds were also detected and tentatively identified by gas chromatography-mass spectrometry . Since, previous studies have shown that polycyclic aromatic hydrocarbons may react with NO2 to form direct-acting mutagens, it appears that the direct-acting mutagens in these fly ash extracts may be products of reactions of polycyclic aromatic hydrocarbons with NOX in the combustion gases. Cancer Lett, 1983 Apr, 18(3), 271 - 5 Mutagenicity of N-nitrosobis(2-hydroxypropyl)amine and its related compounds in the presence of rat lung and liver S9; Mori Y et al.; The mutagenic activities of N-nitrosobis(2-hydroxypropyl)amine (BHP) and its related compounds were studied in Salmonella typhimurium TA100 and TA98 strains by Ames's liquid incubation assay in the presence or absence of lung and liver S9 of rats treated with polychlorinated biphenyl (PCB) . BHP and its related compounds, N-nitroso-(2-hydroxypropyl)(2-oxopropyl)amine (HPOP), N-nitrosobis(2-oxopropyl)amine (BOP), N-nitrosobis(2-acetoxypropyl)amine (BAP), and N-nitroso-2,6-dimethylmorpholine (NDMM) showed negative mutagenicity in the absence of lung and liver S9 in TA100 and TA98 strains while those compounds showed positive in the presence of liver S9 in TA100 strain . HPOP and BOP showed positive mutagenic activity in the presence of lung S9 in TA100 strain . HPOP showed the strongest mutagenic activity in the presence of lung and liver S9. Ann Ophthalmol, 1983 Apr, 15(4), 321 - 2 Endogenous endophthalmitis due to Salmonella typhimurium; Shohet I et al.; Endogenous endophthalmitis due to Salmonella typhimurium is reported in a 1-year-old child . Despite vigorous antibiotic therapy, the child's vision deteriorated, and loss of light perception occurred in the infected eye . Endophthalmitis is a very rare complication of salmonellosis, and it should alert physicians because of its severe damage to the eye. J Appl Physiol, 1983 Apr, 54(4), 1167 - 71 Reproducibility of cardiopulmonary effects of different endotoxins in the same sheep; Traber DL et al.; This study compares qualitative and quantitative differences between the cardiopulmonary responses to Salmonella typhimurium and Escherichia coli 055:B5 endotoxins (Difco) in the same sheep model . Lipopolysaccharides, 0.75 micrograms/kg, were infused into chronically instrumented sheep over 30 min . Cardiopulmonary and pulmonary lymph flux data were collected for 2 h prior to and 6 h following this . One week later the sequence was repeated with another endotoxin . The administration of the two endotoxins was varied: some received S . typhimurium first; others received E . coli . A total of 13 animals were studied; 8 had intact pulmonary lymphatic catheters . Following each injection of endotoxin these animals showed a typical response of early high pressure-mediated increase in pulmonary lymph flow and later lymph flow elevation associated with a very mild increase in microvascular pressure and lymph with normal protein levels . These changes were associated with hemoconcentration, lowered arterial oxygen partial pressure, cardiac index, and blood neutrophil count . It is concluded that Difco S . typhimurium and E . coli endotoxins are similar in their mechanism of action and potency and can be studied in the same animal. Mutat Res, 1983 Apr, 120(1), 7 - 11 Mutagenicity and co-mutagenicity of catechol on Salmonella; Yoshida D et al.; Catechol was not mutagenic for Salmonella typhimurium TA98, TA100 or TA1537 in the presence or absence of S9 mix . At the lower level of S9 in the Ames method, the mutagenic activity of benzo{a}pyrene decreased with the increased addition of catechol . When catechol was added to the pre-incubation mixture at a higher concentration than in the conventional Ames method, the mutagenic activity of benzo{a}pyrene increased with the increased addition of catechol . Catechol is believed to be a co-mutagen for benzo{a}pyrene in the presence of a sufficient amount of S9 in the incubation mixture. Mutat Res, 1983 Apr, 117(1-2), 93 - 104 Determining the mutagenic activity of a tar, its vapors and aerosols; Penalva JM et al.; The Ames test was performed on Salmonella typhimurium, strain TA98, TA100, TA1535, TA1537, TA1538, to evaluate the mutagenic potential of a tar as well as its vapors and aerosols emitted at 250, 350 and 550 degrees C . Two chemical procedures were used: extractions of aromatics for DMSO; elimination of acids, alcohols and phenols . Weak mutagenic activity was demonstrated at each temperature . Then, using only Salmonella typhimurium strains TA98 and TA100, a study was made on the effects of the mutagenic compounds, benzo{a}pyrene, 2-aminoanthracene, nitrofluorene, methyl methanesulfonate and on the vapors and aerosols emitted at 350 degrees C by road-coating tar . For promutagenic compounds, an enhancing effect was observed before an inhibition effect . For direct mutagenic compounds, only the inhibition effect appeared . The mutagenic and/or carcinogenic activity was usually tested on a pure isolated chemical compound. Mutat Res, 1983 Apr, 117(1-2), 47 - 54 Mutagenicity of methyl nitrite in Salmonella typhimurium; Tornqvist M et al.; Methyl nitrite was tested for mutagenicity in Salmonella typhimurium TA1535 . In the first set of experiments, plated bacteria were exposed to methyl nitrite in desiccators both in the absence and presence of a metabolizing system (S9 from Aroclor-pretreated Sprague-Dawley rats) . Initial concentrations from 125 to 500 ppm were tested . In all experiments an increased initial concentration gave an increased mutagenic response . The mutagenic effect in the presence of S9 was similar to that in the absence of S9 . Owing to difficulties in dose determinations in this type of experiment it could not be decided, unequivocally, whether the mutagenic effect was caused by methyl nitrite or its hydrolysis products . Experiments were therefore carried out in suspension, and the concentrations of methyl nitrite and inorganic nitrite were determined . Treatments with inorganic nitrite were also carried out under similar conditions . From the results of these experiments we concluded that methyl nitrite is mutagenic . Possible mechanisms of action of methyl nitrite are discussed, and it is suggested that mutagenicity may be a general property of alkyl nitrites. Mutat Res, 1983 Apr, 117(1-2), 41 - 6 Mutagenicity in Salmonella typhimurium TA98 of the serum extract of the organic matter derived from airborne particulates; Takeda N et al.; To investigate the interactions between mutagens and serum components, the mutagenicity of the serum extract of the organic matter derived from airborne particulates (tar) was examined by the Salmonella/mammalian microsome mutagenicity test . The mutagens in the organic matter were found to be extracted with serum but not with saline . The mutagenic activity of the serum extract of the tar, however, decreased to about 60% compared with that of the DMSO extract, when they were activated by S9 mix . On the other hand, without S9 mix, the mutagenic activities of the serum and DMSO extracts were about the same . Gel filtration of the serum extract was carried out and followed by mutagenicity testing of each fraction . It is suggested that the mutagens, which require metabolic activation, combine mainly with beta-lipoproteins and the direct mutagens with both alpha- and beta-lipoproteins in serum. Mutat Res, 1983 Apr, 117(1-2), 21 - 9 Mutagenicity of dichloroacetylene and its degradation products trichloroacetyl chloride, trichloroacryloyl chloride and hexachlorobutadiene; Reichert D et al.; Dichloroacetylene (DCA) is a highly reactive compound that decomposes rapidly in contact with air into a series of chlorinated aliphatic hydrocarbons (e.g., phosgene, trichloroacetyl chloride, trichloroacryloyl chloride and hexachlorobutadiene) . Experiments were performed to compare the mutagenic properties of DCA and its degradation products on the histidine-dependent tester strains TA98 and TA100 of Salmonella typhimurium . In these experiments, DCA vapour was streamed under analytical control through the bacterial suspensions . DCA is soluble in aqueous solution and was stable under the experimental steady-state conditions of the bacterial exposure . There is a linear correlation between the supply of DCA vapour and solubilized DCA in the range of 1000 and 16 000 ppm . Mutagenic response was observed with strain TA100 if the bacteria were suspended in Oxoid medium . No mutagenicity could be detected with strain TA98 . DCA mixtures with acetylene, as used as stabilizer for animal experiments, were not mutagenic in either bacterial strain, irrespective of the presence or absence of S9 mix in the cell suspension . One of the degradation products of DCA, trichloroacryloyl chloride, showed pronounced mutagenic properties with and without drug-metabolizing enzymes . Other degradation products of DCA, such as trichloroacetyl chloride and hexachlorobutadiene, were not mutagenic, either in the presence or absence of liver homogenate. Mutat Res, 1983 Apr, 117(1-2), 193 - 9 Mutagenicity of oxytetracycline; Blitek D et al.; Oxytetracycline hydrochloride, potassium nitrite and a combination of this antibiotic with the nitrite were tested for their mutagenicity in the host-mediated assay with mice as the host animals . The Salmonella typhimurium strain used was his G46 . The bacteria were injected intraperitoneally, and the test compounds were administered by a stomach tube . Neither oxytetracycline nor potassium nitrite were mutagenic for strain G46, but the combination of the compounds administered in the highest tolerated doses proved to be mutagenic for this Salmonella strain . The mutagenicity of the compounds was further evaluated by the micronucleus test in the bone marrow of Swiss mice . The test compounds were administered p.o., half the dose 30 h and the rest 6 h before the animals were killed . Oxytetracycline and the combination of oxytetracycline with potassium nitrite induced a significant increase in the frequency of micronuclei in polychromatic erythrocytes . Dose-response experiments with oxytetracycline and with the combination of the antibiotic with nitrite revealed an apparent no-effect level at 2 X 50 to 2 X 500 mg/kg . At higher doses both oxytetracycline and oxytetracycline with nitrite significantly influenced the ratio of erythrocytes to nucleated cells . The findings were compared with data obtained with dimethylnitrosamine included in both kinds of experiment. Mutat Res, 1983 Apr, 117(1-2), 113 - 25 Modulation of aromatic amine mutagenicity in Salmonella typhimurium with rat-liver 9000 g supernatant or monolayers of rat hepatocytes as an activation system; Holme JA et al.; 2-Aminofluorene (AF), 2-acetylaminofluorene (AAF) and N-hydroxy-2-acetylaminofluorene (N-OH-AAF) were studied for mutagenic activity in S . typhimurium and either liver 9000 g supernatant fractions (S9) or monolayer cultures of hepatocytes isolated from Wistar rats were used as an activation system . All 3 compounds were converted into mutagens excreted into the incubation medium by the cell-culture system, with N-OH-AAF greater than AF greater than AAF . Cultures used 24 h after plating were less efficient in promutagen conversion than were cultures used after 2 h . Phenobarbital, but not 3-methylcholanthrene, pretreatment of the rats caused similar effects on AF, AAF and N-OH-AAF mutagenicity with both S9 and hepatocyte cultures . The mutagenicities of AF and AAF were reduced by the cytochrome-P-450 inhibitors metyrapone and alpha-naphthoflavone, whereas the mutagenicity of N-OH-AAF was increased by using both inhibitors . Further, the microsomal deacetylase inhibitor paraoxon caused only a moderate reduction in N-OH-AAF mutagenicity, but a total inhibition of AAF mutagenicity . No significant effect of paraoxon on AF mutagenicity was seen . With the S9 system, no effect of ascorbate on the mutagenicity of AF, AAF or N-OH-AAF was observed . In contrast, the mutagenicity of all 3 compounds was increased by ascorbate when hepatocyte cultures were used as activation system . Incubation of hepatocyte monolayers in a sulfate-free medium did not change the mutagenicity of AF, AAF or N-OH-AAF . Galactosamine, an inhibitor of glucuronidation in cells, increased the mutagenicity of AF, AAF and N-OH-AAF with hepatocyte cultures . The addition of cofactor for glucuronidation in the S9 system, however, had no effect . A reduction in mutagenicity of AF and AAF, but not that of N-OH-AAF, was observed with the addition of glutathione (GSH) in both the S9 and the hepatocyte systems . On the other hand, no effect of cellular GSH depletion was seen on aromatic-amine mutagenicity in the hepatocyte system . The data indicate that the hepatocyte culture system offers advantages over the conventional liver-sub-fraction activation system as a model, in vivo, for the metabolism of the aromatic amine mutagens/carcinogens. Mutat Res, 1983 Apr, 117(1-2), 105 - 12 Conversion of Congo red and 2-azoxyfluorene to mutagens following in vitro reduction by whole-cell rat cecal bacteria; Reid TM et al.; Congo red, an azo dye derived from benzidine, and 2-azoxyfluorene, a derivative of 2-aminofluorene, were reduced during overnight incubation with a suspension of rat intestinal bacteria . High performance liquid chromatography and ultraviolet spectral analysis verified the presence of benzidine in extracts of the Congo red incubations and 2-aminofluorene in extracts of the 2-azoxyfluorene incubations . Extracts of the Congo red incubations were mutagenic toward Salmonella typhimurium TA1538 in the presence of a post-mitochondrial activating system, but Congo red was not mutagenic without this reductive pretreatment . Thus, the utility of the Ames test in screening for potential mutagens may be expanded by a reductive pretreatment utilizing cecal bacteria. Mutat Res, 1983 Apr, 117(1-2), 1 - 8 Mutagenicity of bis- and mono-(2,3-dibromopropyl)phosphate, and their salts used as flame retardants, in the Salmonella/microsome system; Nakamura A et al.; The mutagenicity of pure synthesized samples of bis(2,3-dibromopropyl)phosphate (bis-BP) and mono(2,3-dibromopropyl)phosphate (mono-BP) against Salmonella typhimurium TA100 was examined in relation to microsomal activation of tris(2,3-dibromopropyl)phosphate (tris-BP) . Both mono- and bis-BPs were weak direct mutagens . Their mutagenicities increased with S9 mix, but the rates were much less than that of tris-BP . The magnesium and ammonium salts of mono- and bis-BPs were also prepared and their mutagenicities were examined with S9 mix in relation to 2 commercial flame retardants (our abbreviations: DB-1 and DB-2) . In both mono- and bis-BP series, an apparent increase of mutagenicity was observed in the order: ammonium salt greater than magnesium salt greater than free acid . On the other hand, mono-BP and its salts are usually more active than the corresponding bis-BPs independently of the kind of cation . DB-1 (DB-2), however, is more potent than the magnesium (ammonium) salts of mono- and bis-BPs, the constituents in DB-1 (DB-2) . No synergistic effect between mono-BP salts and bis-BP salts was observed . The different unknown mutagenic compounds in DB-1 and DB-2 are suggested. J Bacteriol, 1983 Apr, 154(1), 84 - 91 flaAII (motC, cheV) of Salmonella typhimurium is a structural gene involved in energization and switching of the flagellar motor; Dean GE et al.; The flaAII gene of Salmonella typhimurium has also been termed motC and cheV, because defective alleles may give rise to a nonflagellate, paralyzed, or nonchemotactic phenotype . We isolated a temperature-sensitive motility mutant (MY1) and have found that the mutation occurs in the flaAII gene . In temperature-jump experiments, MY1 could be converted from highly motile to paralyzed within 0.5 s, demonstrating that flaAII is a structural gene whose product is immediately essential for motor rotation . The mutant, although chemotactic at permissive temperatures (less than 36 degrees C), had a higher clockwise rotational bias than did the wild type; it can therefore be regarded simultaneously as motC(Ts) and cheV (tumbly) . The only previously reported S . typhimurium cheV mutant was smooth-swimming . A shift toward counterclockwise bias accompanied loss of rotational speed in the restrictive temperature range . This result, by analogy with known proton motive force effects on motor switching, further indicates a central role of the flaAII (motC, cheV) protein in the energy transduction and switching process . Since there is no evidence associating it with the isolable entity known as the basal body, it may reside at the cytoplasmic face of the flagellar motor. Infect Immun, 1983 Apr, 40(1), 236 - 44 Effect of lipopolysaccharide mutations on the pathogenesis of experimental Salmonella gastroenteritis; Mintz CS et al.; Lipopolysaccharide mutants of Salmonella typhimurium provoked diminished amounts of fluid in rabbit ileal loops as compared with the response to the wild type . The responses elicited by these mutants ranged from 0 to 60% of that caused by the parent strain . Two completely rough mutants and one leaky rough mutant were chosen for further study . Purified lipopolysaccharide from the parent and the mutant strains failed to stimulate fluid exsorption in ileal loop experiments . Histological studies revealed that the three lipopolysaccharide mutants were less invasive than wild type and were less able to generate an inflammatory reaction in the rabbit ileum . A Salmonella enterotoxin was present in culture filtrates from one rough mutant and the wild type; however, the rough mutant appeared to produce less toxin . Enterotoxic activity was absent in culture filtrates from the two other rough mutants . These results suggest that reductions in both invasiveness and the ability to produce Salmonella enterotoxin decreased the ability of these mutants to provoke fluid exsorption . Also, the results indicate that lipopolysaccharide mutations can have a profound effect on the enteropathogenic properties of S . typhimurium. Food Chem Toxicol, 1983 Apr, 21(2), 221 - 3 Mutagenicity study of nine monoalkyl phthalates and a dialkyl phthalate using Salmonella typhimurium and Escherichia coli; Yoshikawa K et al.; Nine monoalkyl (C1-C8) phthalates and di-(2-ethylhexyl) phthalate (DEHP) were assayed for mutagenicity in two strains of Salmonella typhimurium (TA98 and TA100) and two strains of Escherichia coli WP2 try- (uvrA+ and uvrA-) with and without metabolic activation with S-9 mix . The procedure of Ames et al . (Mutation Res . 1975, 31, 347) was used, with minor modifications . None of the compounds tested showed any mutagenic activity, but all the monoalkyl phthalates showed some lethality towards the S . typhimurium strains, the most toxic being monoheptyl phthalate . A marginally lethal effect on the Salmonella strains was shown by DEHP, but only at the highest concentration tested (2000 micrograms/plate) and in the absence of S-9 mix. Food Chem Toxicol, 1983 Apr, 21(2), 175 - 80 Negative Ames tests of epoxide fatty methyl esters derived from hemolysis of linoleic acid hydroperoxides; Gardner HW et al.; Five isomeric epoxyhydroxyene and epoxyoxoene fatty esters derived from hemolytic decomposition of linoleic acid hydroperoxide were tested for mutagenicity by the "Ames' top-agar incorporation method using S-9 mix derived from livers of male rats pretreated with Aroclor 1254 . The epoxide fatty esters tested--methyl trans-12,13-epoxy-erythro-11-hydroxy-cis(trans)-9-octadecenoate and methyl trans-12,13-epoxy-threo-11-hydroxy-cis(trans)-9-octadecenoate (each composed of approximately 80% cis-9-ene and 20% trans-9-ene), methyl trans-12,13-epoxy-9-oxo-(trans-10-octadecenoate, methyl trans-12,13-epoxy-9-hydroxy-trans-10-octadecenoate and methyl cis-12,13-epoxy-9-oxo-trans-10-octadecenoate--had structural characteristics similar to certain potent mutagens . However, these esters were not mutagenic in Salmonella typhimurium strains TA100, TA98 or TA1537 at concentrations up to 2000 micrograms/test plate . Under the same test conditions, the methyl ester of hydroperoxy linoleic acid, from which these epoxides were derived, was weakly mutagenic in strain TA100 and possibly also in strain TA98. Environ Res, 1983 Apr, 30(2), 427 - 41 The mutagenicity of a Prudhoe Bay crude oil and its residues from an experimental in situ burn; Sheppard EP et al.; Fresh and weathered Prudhoe Bay crude oil as well as residues from its combustion were tested for mutagenicity using strain TA98 in the Ames Salmonella typhimurium/liver microsome test . Because of the toxicity of the oils involved, mutagenic effects were clearly visible only at very low concentrations . All samples were found to be mutagenic, with precipitated plume having the greatest activity followed by the burn residue, the weathered oil, and fresh crude, respectively . The most polar components of the neutral fraction of the samples displayed the greatest mutagenicity. Naturwissenschaften, 1983 Apr, 70(4), 173 - 9 {Microbiological short-time tests for the evaluation of mutagenic potential of chemical substances}; Gericke D; During the last 20 years it became much more interesting to test new chemicals as fast as possible for their carcinogenic potency . Therefore new test models were developed . Mutagenicity seems to be one sign for carcinogenicity . Therefore test systems using microorganisms were studied which are influenced by mutagenic substances . These systems are described, first of all the Ames-Test, using revertants of Salmonella typhimurium, secondly the Escherichia coli system deficient of DNA-polymerase A (DNA-Pol A-) . The yeast Saccharomyces cerevisiae was introduced some years ago and finally the Neurospora crassa system serves as an additional test to define exactly the localisation of mutations . The tests and their problems are discussed. J Natl Cancer Inst, 1983 Apr, 70(4), 767 - 9 Increased mutagenicity of chloroethylnitrosoureas in the presence of a rat liver S9 microsome mixture; Suling WJ et al.; The mechanism for an enhanced effect of Aroclor 1254-induced Sprague-Dawley rat liver 9,000 x g supernatant (S9) microsome preparation on the mutagenicity of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), 1-(2-chloroethyl)-3-cyclohexyl-N-nitrosourea (CCNU), and 2-{3-(2-chloroethyl)-3-nitrosoureido}-2-deoxy-D-glucopyranose (chlorozotocin) for Salmonella typhimurium strain TA1535 was studied . Although all three compounds were direct-acting mutagens, rat liver S9 increased the mutagenic response to BCNU, CCNU, and chlorozotocin . The enhanced mutagenic effect was independent of NADPH . Heat-denatured S9 enhanced the mutagenicity of BCNU and CCNU, but not that of chlorozotocin . Mutagenic enhancement, however, was less than that observed with untreated S9 . The substitution of extractable S9 lipid and bovine serum albumin for S9 in the reaction mixture resulted in an enhanced mutagenicity of CCNU with little or no effect on BCNU or chlorozotocin mutagenicity . These results suggest that the enhanced mutagenicity of CCNU, and possibly that of BCNU, in the presence of S9 was due in part to nonspecific factors that are present in the S9 preparation. Mutat Res, 1983 Apr, 117(1-2), 31 - 40 Microbial mutagenicity of 3- and 4-ring polycyclic aromatic sulfur heterocycles; Pelroy RA et al.; The stable isomers of 3- and 4-ring polycyclic aromatic sulfur heterocycles were tested for mutagenicity in the Ames standard plate incorporation test and a liquid pre-incubation modification of the Ames test . Of the 4 three-ring compounds tested, only naphtho{1,2-b}thiophene was mutagenic . Of the four-ring compounds, 7 of 13 were mutagenic in the standard Ames or pre-incubation Ames test . The highest activity for the 4-ring compounds was observed for phenanthrol{3,4-b}thiophene, a compound of approximately the same mutagenic potency in the Ames test as benzo{a}pyrene . The other active 4-ring compounds were of considerable less mutagenic potency than phenanthrol{3,4-b}thiophene . Mutagenicity for two of the 4-ring aromatic thiophenes could only be detected in the liquid pre-incubation Ames test . Salmonella typhimurium TA100 was the most sensitive strain to mutagenesis by these compounds, followed by TA98 . All mutagenesis was indirect, requiring metabolic activation. J Biol Chem, 1983 Mar 25, 258(6), 3769 - 74 Salmonella typhimurium mutants defective in UDP-D-galactose:lipopolysaccharide alpha 1,6-D-galactosyltransferase . Structural, immunochemical, and enzymologic studies of rfaB mutants; Wollin R et al.; The biochemical defect in a class of Salmonella typhimurium mutants (rfaB) defective in biosynthesis of the lipopolysaccharide core is described . Structural, immunochemical and enzymologic studies showed that: (i) the core polysaccharide completely lacked the branch alpha 1,6-D-galactosyl residue of the normal lipopolysaccharide as shown by methylation analysis and 1H nmr spectroscopy; (ii) the mutant lipopolysaccharides acted as acceptors for transfer of D-galactose from UDP-D-galactose into alpha 1,6 linkage to the proximal D-glucosyl residue of the core in a reaction catalyzed by an enzyme activity present in extracts from rfaB+ cells; (iii) the UDP-D-galactose:(glucosyl)lipopolysaccharide alpha 1,6-D-galactosyltransferase activity was absent from extracts of rfaB cells. Science, 1983 Mar 25, 219(4591), 1427 - 9 Activation of 2-aminofluorene by cultured plant cells; Plewa MJ et al.; Cultured tobacco plant cells activated 2-aminofluorene to an agent mutagenic to Salmonella typhimurium strain TA98 . The plant activation of 2-aminofluorene is heat-inactivated and may not involve solely cytochrome P-450 . The kinetics of activation demonstrated both time- and concentration-dependent responses. Biochim Biophys Acta, 1983 Mar 15, 756(1), 41 - 8 Different biosynthetic pathways of the pyrimidine moiety of thiamin in procaryotes and eucaryotes; Yamada K et al.; {14C}Formate is incorporated into the C-2 of the pyrimidine moiety of thiamin by Escherichia coli and Salmonella typhimurium . In Saccharomyces cerevisiae, it is incorporated into C-4 . Radioactive carbons of {1-14C}glycine and {2-14C}glycine are incorporated by S . typhimurium into the C-4 and C-6 of the pyrimidine, respectively, but not by S . cerevisiae . These facts suggest that procaryotes and eucaryotes have different biosynthetic pathways for pyrimidine . In this study, the procaryotes tested incorporated {14C}formate into the C-2 and the eucaryotes incorporated it into the C-4 of the pyrimidine. J Biol Chem, 1983 Mar 10, 258(5), 3266 - 79 Genetic characterization of the folding domains of the catalytic chains in aspartate transcarbamoylase; Jenness DD et al.; In Salmonella typhimurium strains which produce high constitutive levels of aspartate transcarbamoylase due to the pyrH700 mutation, the bulk of the carbamoyl phosphate of the cell is consumed for the biosynthesis of pyrimidines . As a consequence, there is little substrate available for arginine synthesis and the cell growth is impeded . Suppression of arginine auxotrophy by mutations which block aspartate transcarbamoylase activity provides a positive selection technique for mutant strains defective in this enzyme activity . A genetic analysis was performed on 29 mutant strains harboring defects in the structural gene pyrB, encoding the catalytic chains of aspartate transcarbamoylase of Escherichia coli . Extracts from 15 strains contained intact, inactive enzyme-like molecules of the same size as the purified wild type enzyme . These same extracts contained a predominant polypeptide chain which migrated electrophoretically at the same rate as catalytic chains from wild type enzyme . In addition to these 15 different missense mutants, 14 others (presumably chain-terminating mutants) were isolated; no polypeptides corresponding to full length catalytic chains were detected in these strains . Based on their reversion and suppression properties, seven were designated as frameshift and two as amber nonsense . A fine structure recombination map of the pyrB locus was constructed from a series of three-factor transductional crosses . Mutational sites were correlated with regions in the polypeptide sequence by relating their map positions to that of mutation pyrB231 which results in an amino acid replacement at position 128 . Moreover, since recent crystallographic studies indicate that residue 128 is located near the junction between the NH2- and COOH-terminal folding domains, the mutational sites can be placed within either of these two regions of tertiary structure . Interallelic complementation experiments showed four units of complementation . Those defining the alpha and beta units were missense mutants with their mutational sites in the NH2- and COOH-terminal domains, respectively . The mutants determining the delta and gamma units involved premature polypeptide chain termination and their mutational sites were correlated with distal regions of the two respective domains . Several mutants of the chain-terminating type failed to complement members of more than one unit . Possible effects of the various mutations and their implications for mechanisms of complementation and enzyme activity are presented. J Biol Chem, 1983 Mar 10, 258(5), 2870 - 4 Purification and characterization of recA protein from salmonella typhimurium; Pierre A et al.; recA protein was purified to homogeneity from Salmonella typhimurium TA98 strain after induction of the cells by nalidixic acid . The purification was monitored with a radioimmune assay and involved a specific elution of the protein by ATP from a single-stranded DNA-cellulose column . From 240 liters of cell culture we obtained 40 mg of recA protein which was more than 98% pure . This protein exhibited the same molecular weight as measured on sodium dodecyl sulfate-polyacrylamide gel and the same isoelectric point as the Escherichia coli recA protein purified by a similar procedure . In addition, the S . typhimurium recA protein is endowed with a single-stranded DNA-dependent ATPase activity and cleaves the phage lambda repressor in vitro at the same rate as E . coli recA protein and with the same qualitative requirements . However, peptide mapping with the Staphylococcus aureus V8 protease and cross-reaction with heterologous antibodies show that these two proteins are slightly different. Mutat Res, 1983 Mar, 116(3-4), 361 - 7 Induction of chromosome damage by methylene chloride in CHO cells; Thilagar AK et al.; The genotoxicity of methylene chloride was determined using sister-chromatid exchange (SCE) and chromosome aberration assays in cultured Chinese hamster ovary (CHO) cells . Methylene chloride caused extensive chromosome aberrations both with and without metabolic activation . However, the results of the SCE assay were negative for methylene chloride . These results agree with previously observed genotoxic effects of methylene chloride in Salmonella typhimurium and Saccharomyces cerevisiae . The fact that methylene chloride causes chromosome aberrations without increasing the SCE level indicates that complete reliance on the induction of SCE as a test system for assessing chromosomal effects is not valid. Environ Health Perspect, 1983 Mar, 49, 21 - 5 N-hydroxylation of carcinogenic and mutagenic aromatic amines; Kato R et al.; N-Hydroxylation and mutagenic activation of heterocyclic aromatic amines from protein pyrolysis products were studied in rat liver microsomes and nuclei, rat hepatocytes and various species of purified cytochrome P-450 . These mutagenic amines include Trp-P-2 (3-amino-1-methyl-5H-pyrido{4,3-b}indole), Trp-P-1 (3-amino-1,4-dimethyl-5H-pyrido{4,3-b}indole), Glu-P-1 (2-amino-6-methyldipyrido-{1,2-a:3',2'-d}imidazole), Glu-P-2 (2-amino-dipyrido{1,2-a:3',2'-d}imidazole) and IQ (2-amino-3-methyl-3H-imidazo-{4,5-f}quinoline) . The number of revertants of Salmonella typhimurium TA 98 was always correlated to the amount of each of the N-hydroxylated metabolites in various experimental conditions . The N-hydroxylated amines covalently bound to DNA directly or after being acylated with amino acids by amino-acyl-tRNA synthetase . Various species of cytochrome P-450 preparations showed markedly different activity in N-hydroxylation and mutagenic activation of Trp-P-2, Glu-P-1 and IQ . A high spin form of cytochrome P-450, isolated from the liver of PCB-treated rats, showed very high activity in N-hydroxylation of Trp-P-2, Glu-P-1 and 2-aminofluorene, although its activity was very low in benzo(a)pyrene hydroxylation . The present results indicate that different species of cytochrome P-450 are involved in the N-hydroxylation and mutagenic activation of aromatic amines. J Med Chem, 1983 Mar, 26(3), 309 - 12 Mutagenicity and chemistry of N-nitroso-N-(p-substituted-benzyl)methylamines; Singer GM et al.; The relative mutagenicities of N-nitroso-N-(p-substituted-benzyl)methylamines in Salmonella typhimurium TA 1535 were tested in order to determine whether biological activity is affected by the electron density at a nitrosamine alpha carbon . The order of potency was as follows: X = Cl greater than CN greater than Br greater than NO2 greater than H greater than CH3O greater than CH3 greater than F much greater than COOH . No direct correlation was apparent, nor was there any obvious correlation between biological activity and the extent of base-catalyzed hydrogen-deuterium exchange at the alpha carbons. Trop Geogr Med, 1983 Mar, 35(1), 37 - 41 Drug resistance among Salmonellae in Kuwait; Chugh TD et al.; The status of drug resistance among Salmonella spp . prevalent in Kuwait during 1979-1980 has been assessed . Antibiotic sensitivity of 345 clinical isolates against 14 antimicrobial agents was done by disc-diffusion technique and their MIC was determined by plate dilution . Only 9.6% of these isolates were sensitive to all the 14 drugs . There was resistance to sulfisoxazole (78%), tetracycline (69%), kanamycin (61%), ampicillin (56%), streptomycin (53%), chloramphenicol (38%) and mezlocillin (38%) . Multiple drug resistance (three or more drugs) was seen in 71% of isolates and many of them were resistant to five or more drugs . The common resistance patterns observed were ACGKSSuT, ACKSSuT, ACSSuT, and ASSuT . Co-trimoxazole was the drug of choice as only 15 strains (4%) were resistant to it . The minimum inhibitory concentration (MIC) of the resistant strains was invariably high . Salmonella typhimurium was the commonest (41%) single species and the frequency and level of resistance was higher in this serotype than in others. Bull Eur Physiopathol Respir, 1983 Mar-Apr, 19(2), 143 - 5 Resistance to infection: looking for new genes; Glynn AA; Genetic factors in resistance to infection, somewhat neglected with the development of microbiology, are again receiving careful attention . Although there are numerous reports of infection resulting from deficiencies in, for example, immunoglobulins or complement components, specific abnormalities in resistance associated with particular HLA groups have been unexpectedly rare . In mice, the Ity gene on chromosome 1, which is important in resistance to Salmonella typhimurium infection, may well be identical with the Lsh and Bcg genes concerned with resistance to Leishmania donovani and Mycobacterium bovis BCG . The most likely common factor determining resistance to three such disparate organisms is the macrophage, but direct evidence of its role is lacking . The high and low antibody-producing strains of mice selected by BIOZZI {2} are respectively sensitive and resistant to many intracellular infections including S . thyphimurium . Experiments with hybrids between Biozzi mice and other inbred strains suggest that the high line carries the Itys (salmonella susceptibility gene) plus another gene increasing susceptibility . Low line mice carry the Ityr gene plus another gene increasing resistance . Inbred mice are invaluable for analogizing gene interactions which, once understood, can be looked for in man. Mutat Res, 1983 Mar, 119(3), 289 - 91 Evaluation of mutagenic effect of the fungicide fenaminosulf in Drosophila melanogaster; Pai SB; Fenaminosulf (p-dimethylaminobenzenediazo sodium sulfonate, CAS registry No . 140-56-7) which is an active ingredient in several commercial fungicides was reported to be mutagenic in Salmonella typhimurium (McCann et al., 1975), Bacillus subtilis (Kada et al., 1974) and shown to cause chromosome aberrations in plants (Zutshi and Kaul, 1975) . Since fenaminosulf has structural similarity to the potent carcinogen, butter yellow (p-dimethylaminoazobenzene, CAS registry No . 60-11-7), the present studies were undertaken to evaluate the mutagenic potential of this fungicide in Drosophila melanogaster . Fenaminosulf administered at 10 mg/100 ml food medium failed to induce sex-linked recessive mutations in Drosophila . Since Drosophila has drug-metabolizing enzymes similar to those of mammals (Vogel, 1975), it is suggested that the lack of mutagenic activity of fenaminosulf could be due to the conversion of fenaminosulf to non-mutagenic derivatives in Drosophila. Zentralbl Bakteriol Mikrobiol Hyg {A}, 1983 Mar, 254(1), 69 - 77 {Plasmid patterns of Salmonella typhimurium lysotype n.c . 1/72/n.c . strains from East Germany}; Tietze E et al.; Salmonella typhimurium strains isolated in the German Democratic Republic between 1972 and 1980 mainly belong to phage type n.c.1/72/n.c . and biochemotype b . Nearly all of these strains are characterized by an identical basic plasmid pattern . Thus, they may be considered to be independent isolates of the same epidemic strain . Moreover, some multiple drug resistant offsprings of that epidemic strain have been characterized by their carriage of an additional IncH-1 R plasmid . However, a few strains of phage type n.c.1/72/n.c . were found to differ fundamentally in their plasmid patterns from that of the epidemic strain . The phage pattern of these strains is determined by a conjugative R plasmid belonging to the incompatibility group IncI4 . Despite of the same phage- and biochemotype these strains must be considered non-related with the epidemic strain, therefore . The analysing of the plasmid pattern of bacterial strains turns out to be an important contribution to the investigation of epidemic processes. Toxicology, 1983 Mar-Apr, 26(3-4), 207 - 12 Lack of mutagenic activity of dimethylformamide; Antoine JL et al.; Different test systems have been utilized to evaluate the mutagenic and carcinogenic properties of dimethylformamide (DMF), an aliphatic amide used as a solvent in chemical industry . The Ames test was performed on different strains of Salmonella typhimurium, whereas the ability of DMF to induce structural aberrations in eukaryotic chromosomes was tested by in vitro observations on human lymphocytes and in vivo experiments on mouse bone marrow . Furthermore, male mice were treated with DMF for the induction of sperm abnormalities . The negative results obtained in all test systems as well as the absence of positive reports in man or in experimental animals with respect to induction of cancers suggest strongly that DMF is devoid of mutagenic or carcinogenic properties. Zh Mikrobiol Epidemiol Immunobiol, 1983 Mar, (3), 26 - 32 {Biological characteristics of Salmonella typhimurium obtained from different sources 1975-1980}; Kamenskaia IN et al.; Distinct differences in a number of biological properties between S . typhimurium hospital strains and cultures of animal origin have been revealed . During 1975-1980 changes in the fermentation of lysine were observed in hospital strains and the retarded fermentation of sorbitol was revealed in strains of animal origin . S . typhimurium 1R, a new highly virulent biovariant resistant to antibiotics, and enzymatic varieties of biovar 11S were isolated . The nonstability of enzymatic differences between hospital strains and cultures of animal origin necessitates their constant observation in order to differentiate these cultures for the purpose of epidemic analysis . Complete correlation between the properties of cultures circulating on a limited territory and the character of morbidity in Salmonella infection demonstrates the epidemiological importance of the intraspecific differentiation tests under study. Infect Immun, 1983 Mar, 39(3), 1481 - 4 Polyclonal activation of B-lymphocytes in vivo by Salmonella typhimurium lipoprotein; Johnson RB et al.; Lipoprotein prepared from the outer membrane of Salmonella typhimurium is a polyclonal activator of murine B-lymphocytes . It was shown to be mitogenic for splenic cultures, stimulating increased incorporation of {3H}thymidine into DNA . When injected intravenously into mice, the lipoprotein induced splenomegaly and polyclonal B-cell activation . The latter was evident from an increase in the number of plaque-forming cells against trinitrophenylated sheep erythrocytes . Similar results were obtained with Escherichia coli lipoprotein. Infect Immun, 1983 Mar, 39(3), 1187 - 95 Effect of growth phase and cell envelope structure on susceptibility of Salmonella typhimurium to the lactoperoxidase-thiocyanate-hydrogen peroxide system; Purdy MA et al.; The lactoperoxidase-thiocyanate-hydrogen peroxide system was found to have both bacteriostatic and bactericidal activities against strains of Salmonella typhimurium . The bactericidal activity was clearly dependent on the permeability of the bacterial cell envelope . The deep rough mutant TA1535, with the most permeable cell envelope, was killed both at neutral and acid pH, whereas very little or no killing was observed with the intact cells of the parent strain hisG46 . The delta gal mutant, TA1530, representing an intermediate in cell envelope permeability, was inhibited to a much lesser extent than TA1535 . Bacteria in log phase of growth were more sensitive to the bactericidal effects than were those in stationary phase . Growth phase had little influence on the bacteriostatic effects . The hisG46 strain produced significant quantities of acid in the presence of glucose . This acid production was inhibited by the lactoperoxidase-thiocyanate-hydrogen peroxide system, and, in contrast to results obtained with several strains of streptococci, this inhibition was not reversed by addition of a reducing agent (2-mercaptoethanol). Mutat Res, 1983 Mar, 116(3-4), 399 - 405 Absence of mutagenic activity of WHR-1142A, lidamidine hydrochloride, in 4 short-term tests for mutagenic/carcinogenic potential; Allen JA et al.; WHR-1142A, lidamidine hydrochloride, an antidiarrhoeal agent, was tested for possible mutagenic/carcinogenic activity in the Ames Salmonella typhimurium/metabolic activation test, the micronucleus test, by analysis of metaphase chromosomes obtained from human lymphocytes grown in culture and in a cell transformation assay . No evidence of mutagenic/carcinogenic activity due to WHR-1142A, lidamidine hydrochloride, was found in any of the 4 tests. Mutat Res, 1983 Mar, 116(3-4), 305 - 15 Mutagenicity of selected sulfonated azo dyes in the Salmonella/microsome assay: use of aerobic and anaerobic activation procedures; Brown JP et al.; A selection of 16 sulfonated azo dyes of both the monoazo type and diazo dyes based on benzidine, o-tolidine and o-dianisidine were assayed for mutagenicity in Salmonella typhimurium strains TA98 and TA100 employing both aerobic and anaerobic preincubation procedures . 3 food dyes, FD & C Red No . 40 and Yellows No . 5 and No . 6 were non-mutagenic in all tests . 5 dyes were mutagenic with aerobic treatment (trypan blue, Pontacyl Sky Blue 4BX, Congo Red, Eriochrome Blue Black B, dimethylaminoazobenzene) and 6 were mutagenic aerobically with riboflavin and cofactors (Deltapurpurin, trypan blue, Pontacyl Sky Blue 4BX, Congo Red, methyl orange, Ponceau 3R) . Anaerobic preincubation involving enzymatic reduction of the dyes led to a different pattern of mutagenicity, with trypan blue giving much enhanced mutagenicity; Eriochrome Blue Black B, Pontacyl Sky Blue 4BX, Deltapurpurin and Congo Red exhibiting similar activity to aerobic preincubation; and methyl orange and Ponceau 3R yielding no mutagenicity . The results are interpreted with respect to an hypothesis involving partial reduction of the azo bond under differing degrees of aerobiosis via azo-anion radicals and hydrazo intermediates. Mutat Res, 1983 Mar, 116(3-4), 297 - 304 Mutagenicity of anthraquinones in the Salmonella preincubation test; Tikkanen L et al.; The mutagenicities of 15 naturally occurring anthraquinones were examined in Salmonella typhimurium strains TA98, TA100 and TA2637 by the preincubation method . 7 of the 15 compounds tested, i.e., chrysazin, emodin, islandicin, alizarin, chrysophanol, 2-hydroxyanthraquinone and emodic acid, were strong mutagens in strain TA2637 with metabolic activation . All of these compounds contain 1-3 hydroxyl groups, and some also have methyl groups . Cynodontin, an anthraquinone with 4 hydroxyl groups and 1 methyl group, was only slightly mutagenic in strain TA2637 . 2-Hydroxyanthraquinone, alizarin, emodin, islandicin and chrysazin were also mutagenic in strain TA100 with S9 mix . All the bisanthraquinones tested, i.e., skyrin, (+)rugulosin, (-)luteoskyrin, (-)rubroskyrin and sennoside A, were non-mutagenic in this test system with or without metabolic activation . Unsubstituted anthraquinone and anthrone were also non-mutagenic . These results show that hydroxyl substituents are necessary for the mutagenicity of anthraquinones, the optimal substitutions being 1-3 hydroxyl groups per molecule . The 4th hydroxyl group, in the compound cynodontin reduces the mutagenicity considerably. Mutat Res, 1983 Mar, 116(3-4), 217 - 38 Structural specificity of aromatic compounds with special reference to mutagenic activity in Salmonella typhimurium--a series of chloro- or fluoro-nitrobenzene derivatives; Shimizu M et al.; The mutagenicity of 21 chloro- or fluoronitrobenzene compounds and 9 chloro- or fluorobenzene compounds in Salmonella typhimurium (strains TA98, TA1538, TA1537, TA100 and TA1535) was examined . The tests were carried out under the conditions of absence and presence of liver microsomal activation . 15 nitro-group compounds had mutagenic activity; above all, compounds of fluoronitrobenzene were mutagenic for both types of strain . On the other hand, chloronitrobenzene compounds were mutagenic for base-pair substitution strains only . Mutagenic activity was exhibited by all compounds having a chloro or fluoro substituent at the para and ortho position in the nitrobenzene nucleus . All compounds without a nitro substituent showed no mutagenic activity. Mutat Res, 1983 Mar, 116(3-4), 185 - 216 Further mutagenicity studies on pesticides in bacterial reversion assay systems; Moriya M et al.; A total of 228 pesticides (88 insecticides, 60 fungicides, 62 herbicides, 12 plant-growth regulators, 3 metabolites and 3 other compounds) was tested for mutagenicity in bacterial reversion-assay systems with 5 strains (TA100, TA98, TA1535, TA1537 and TA1538) of Salmonella typhimurium and a strain (WP2 hcr) of Escherichia coli . 50 pesticides (25 insecticides, 20 fungicides, 3 herbicides, 1 plant-growth regulator and 1 other compound) were found to be mutagenic . 5 of them required metabolic activation (S9 mix) for their activities . Among various chemical groups, organic phosphates, halogenated alkanes and dithiocarbamates showed higher ratios of mutagens . Although 22 of the pesticides tested have been reported to be carcinogenic, 7 of them, i.e., captain, DBCP, EDB, EDC, ETU, HEH and nitrofen, were detected as mutagens in the present assay . Most of the other 15 non-mutagenic carcinogens were organochlorine pesticides such as alpha-BHC, chlorobenzilate, p,p'-DDT, dieldrin and quintozene. Mutat Res, 1983 Mar, 108(1-3), 45 - 56 Rate of induced forward mutation at 3 genetic loci in Salmonella typhimurium; Skopek TR et al.; The rate of forward mutation to 8-azaguanine, 5-fluorouracil and azetidine carboxylic acid resistance was measured in Salmonella typhimurium following treatment with 18 chemical mutagens . Although the absolute frequency of both spontaneous and chemically-induced mutation was different at the markers scored, the 3 selection systems were found to be equisensitive: each system produced a statistically significant response at approximately the same mutagen concentration . This result suggests that in Salmonella the target size present in a given forward mutation assay is sufficiently large to approximate the level of mutation occurring elsewhere in the chromosome in sections of DNA of similar size. Proc Natl Acad Sci U S A, 1983 Mar, 80(5), 1159 - 63 An intermediate step in translocation of lipopolysaccharide to the outer membrane of Salmonella typhimurium; Mulford CA et al.; Evidence for transient localization of newly synthesized lipopolysaccharide at the periplasmic face of the inner membrane has been obtained by immunoelectron microscopic techniques . Salmonella typhimurium galE mutants in which O-antigen synthesis is dependent on addition of exogenous galactose were employed, and the distribution and fate of pulse-synthesized O antigen was examined by indirect ferritin labeling with anti-O-antigen IgG of spheroplasts prepared by treatment with lysozyme/EDTA . O-reactive lipopolysaccharide appeared rapidly at the exposed periplasmic face of the inner membrane after addition of galactose and was rapidly depleted upon termination of the pulse . Control experiments showed that secondary redistribution of lipopolysaccharide from outer membrane did not occur under the conditions employed for spheroplast formation and immunolabeling, and the pulse-chase kinetics were consistent with those expected for an intermediate in translocation of lipopolysaccharide to the outer membrane . In addition, undecaprenol-linked O antigen was detectable at the periplasmic face of the inner membrane within 30 sec after addition of galactose to a galE deep rough double mutant, and it accumulated stably in that location . The mutation in synthesis of the lipopolysaccharide core in the deep rough strain prevents transfer of O-antigen chains from undecaprenol phosphate to lipopolysaccharide . The result suggests that attachment of O antigen to lipopolysaccharide occurs on the extracytoplasmic side of the inner membrane and supports the conclusion that lipopolysaccharide is translocated to the outer membrane from the periplasmic, rather than the cytoplasmic, face of the inner membrane. Mutat Res, 1983 Mar, 119(3), 281 - 5 In vitro production of azide mutagenic metabolite in Arabidopsis, Drosophila and Neurospora; Rosichan JL et al.; The ability of Arabidopsis, Drosophila and Neurospora to convert azide to its mutagenic metabolite was investigated . Cultures of these organisms all contained significant levels of O-acetylserine sulfhydrylase activity . Extracts from each organism produced a product from O-acetylserine and azide in vitro which was mutagenic in Salmonella typhimurium TA1530. J Bacteriol, 1983 Mar, 153(3), 1259 - 65 Oligopeptidase-deficient mutants of Salmonella typhimurium; Vimr ER et al.; An oligopeptidase that hydrolyzes N-acetyl-L-alanyl-L-alanyl-L-alanyl-L-alanine (AcAla4) has been identified in extracts of Salmonella typhimurium . Mutants lacking this activity have been isolated in dcp mutant strains by screening extracts of mutagenized clones for failure to hydrolyze AcAla4 or by screening colonies for inability to use AcAla4 as a nitrogen source . Double mutants (dcp optA) lacking both oligopeptidase A and dipeptidyl carboxypeptidase cannot use AcAla4 as a nitrogen source, although dcp+ optA and dcp optA+ strains grow on this peptide . The mutations responsible for the loss of activity map at a locus (optA) between asd (75 map units) and xylA (78 map units) . Oligopeptidase A hydrolyzes certain N-blocked tetrapeptides, unblocked pentapeptides, and unblocked hexapeptides, usually but not always liberating the C-terminal tripeptide . These two activities seem to be responsible for the production of a large fraction of the dipeptides that accumulate during protein breakdown in a pepN pepA pepB pepD strain. J Bacteriol, 1983 Mar, 153(3), 1252 - 8 Dipeptidyl carboxypeptidase-deficient mutants of Salmonella typhimurium; Vimr ER et al.; Mutants of Salmonella typhimurium deficient in dipeptidyl carboxypeptidase have been isolated by screening for clones unable to use N-acetyl-L-alanyl-L-alanyl-L-alanine (AcAla3) as the sole nitrogen source . An insertion of the transposable element Tn10 near dcp (the locus coding for dipeptidyl carboxypeptidase) has been isolated and used to map the locus in the interval between purB and trp, an otherwise genetically silent region of the S . typhimurium map . All dcp mutants could still grow using N-acetyl-L-alanyl-L-alanyl-L-alanyl-L-alanine (AcAla4) as the sole nitrogen source . Crude extracts from the dcp mutants failed to hydrolyze AcAla3 but retained approximately 80% of the wild-type activity toward AcAla4 . Several lines of evidence indicate that hydrolysis of AcAla4 in the dcp mutant results from the action of a new peptidase distinct from dipeptidyl carboxypeptidase . A mutant strain lacking dipeptidyl carboxypeptidase in addition to peptidases N, A, B, and D showed reduced protein breakdown during carbon starvation compared with a strain lacking only peptidases N, A, B, and D. Res Vet Sci, 1983 Mar, 34(2), 188 - 92 Effect of reticuloendotheliosis virus on the response of chickens to Salmonella typhimurium infection; Motha MX et al.; Groups of 25 chickens free of maternal antibody to reticuloendotheliosis virus (REV) were inoculated with either third or seventh passage REV at either one or seven days of age . Some of the birds inoculated at day 1 with REV were inoculated with Salmonella typhimurium either concurrently or six or 13 days later while some of those inoculated with REV at day 7 were inoculated concurrently with S typhimurium . At day old, infection with S typhimurium alone caused the death of 12 of 25 chicks whereas in the dual infection, using the third passage REV, 18 of 25 birds died . Similarly no seven or 14 day old chickens died when challenged with S typhimurium alone, but previous day-old infection with REV caused a respective mortality of eight of 25 and five of 25 birds . With the seventh passage REV a similar pattern was seen . At day old S typhimurium infection alone killed seven of 25 birds whereas combined with virus the mortality was 14 of 25 and while S typhimurium alone killed none of 25 chicks infected at seven days old, the mortality in birds also infected with REV was 14 of 25 . Combined virus and bacterial infections did not increase the proportion of feathering defects in birds surviving S typhimurium infections . There was a significantly higher proportion of feathering defects in birds infected with third passage virus compared with seventh passage virus . Although a higher proportion of birds had antibody responses to REV in the seventh than in the third passage group, there was no discernible difference in the effect the different viruses had on chickens' susceptibility to S typhimurium. Proc Natl Acad Sci U S A, 1983 Mar, 80(5), 1207 - 11 Synthesis of aspartate transcarbamoylase in Escherichia coli: transcriptional regulation of the pyrB-pyrI operon; Navre M et al.; The first committed reaction in pyrimidine biosynthesis in Escherichia coli and Salmonella typhimurium is catalyzed by the allosteric enzyme aspartate transcarbamoylase (aspartate carbamoyltransferase; carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2), the product of the pyrB-pyrI operon . Regulation of the pyrimidine pathway is achieved in part by changes in the enzyme's catalytic activity as a function of the concentration of substrates and other metabolites as well as by variations in enzyme synthesis in response to changes in cellular levels of pyrimidine nucleotides . Although there is substantial evidence that UTP concentration has a marked influence on expression of the pyrB-pyrI operon, the mechanism of this control is not known . We have cloned the operon and determined the nucleotide sequence of the region preceding the first structural gene (pyrB) . These studies show two regions sharing considerable homology with the consensus sequence of E . coli promoters, a segment that can code for a 44-amino-acid leader peptide, and a sequence very similar to that of the attenuator of the trp operon . RNA transcripts from several bacterial strains were studied by S1 nuclease mapping . Under conditions leading to extensive enzyme synthesis there was a large production of transcript whose 5' end correlated with the putative promoter closer to the structural genes . At low levels of operon expression there was little transcript in the extracts and both promoters appeared to serve as initiation sites . The results are interpreted in terms of transcriptional control of the pyrB-pyrI operon according to an attenuation model that differs in novel ways from the mechanisms proposed for the regulation of amino acid biosynthesis. J Bacteriol, 1983 Mar, 153(3), 1439 - 50 Two alanine racemase genes in Salmonella typhimurium that differ in structure and function; Wasserman SA et al.; Mutations were isolated in a previously undescribed Salmonella typhimurium gene encoding an alanine racemase essential for utilization of L-alanine as a source of carbon, energy, and nitrogen . This new locus, designated dadB, lies within one kilobase of the D-alanine dehydrogenase locus (dadA), which is also required for alanine catabolism . The dadA and dadB genes are coregulated . Mutants (including insertions) lacking the dadB alanine racemase do not require D-alanine for growth unless a mutation is introduced at a second locus, designated dal . Two genes specifying alanine racemase activity were cloned from S . typhimurium . The two cloned DNA sequences do not cross-hybridize with each other; one was shown to contain the dadB gene. J Bacteriol, 1983 Mar, 153(3), 1172 - 9 Identification of the uvrD gene product of Salmonella typhimurium LT2; Pang PP et al.; The product of the uvrD gene of Salmonella typhimurium LT2 and Escherichia coli K-12 is thought to play a role in both the correction of mismatched bases and the repair of DNA damage, since insertion mutations in the uvrD gene increase the spontaneous mutation frequency and make the cells more sensitive to killing by UV irradiation . To clone the uvrD gene of S . typhimurium, we first generated a uvrD-specific probe by using DNA from an S . typhimurium uvrD421::Tn5 mutant . This probe was used to screen a lambda library of S . typhimurium DNA . Bacteriophage carrying intact uvrD+ genes were subsequently identified, and the uvrD+ gene was subcloned onto a low-copy-number vector . By using a combination of Tn1000 insertion mutagenesis and the maxicell technique, the product of the uvrD gene was shown to be a 75,000-dalton protein, and the relative direction of transcription of this protein was determined . Introduction of a low-copy-number plasmid carrying the S . typhimurium uvrD+ gene into uvrD insertion mutants of either S . typhimurium or E . coli restored the spontaneous mutation frequency and degree of UV sensitivity to the levels in the corresponding uvrD+ strains. Infect Immun, 1983 Mar, 39(3), 1265 - 70 Effective antibacterial protection induced by a Listeria monocytogenes-specific T cell clone and its lymphokines; Kaufmann SH; The capacity of the murine Listeria monocytogenes-specific T cell clone 9-36-1 and of lymphokines derived therefrom to induce antibacterial protection in vivo was studied . Clone 9-36-1 was stimulated to proliferate and to produce lymphokines by in vitro culture with syngeneic accessory cells and heat-killed L . monocytogenes . Although 9-36-1 cells were highly active in vitro, intravenous transfer of the cells resulted in marginal protection against a systemic infection with L . monocytogenes . In contrast, 9-36-1 cells injected subcutaneously together with L . monocytogenes into the footpad induced marked protection in syngeneic, but not in allogeneic, mice . Multiplication of Salmonella typhimurium was not reduced by the T cell clone . Studies with 51Cr-labeled T cells indicated that the low activity of intravenously transferred cells was due to an altered migration pattern . Lymphokines produced by 9-36-1 cells in vitro induced protection against L . monocytogenes in syngeneic recipient mice . Lymphokine-induced protection was also demonstrable in allogeneic recipients and against S . typhimurium . These findings suggest that the L . monocytogenes-specific T cell clone 9-36-1, although unable to immigrate into sites of bacterial deposition, had retained its ability to mobilize antibacterial defense mechanisms once present at the site of reaction. J Med Chem, 1983 Mar, 26(3), 455 - 8 Derivatives of beta-adrenergic antagonists . N-Nitrosopropranolol and N-hydroxypropranolol and its aldonitrone; Zhang S et al.; Potential precursors to chemically reactive species derived from the beta-adrenergic antagonist propranolol were synthesized and tested for mutagenicity in the Ames Salmonella assay . N-Hydroxypropranolol (1), the corresponding aldonitrone, 3-(1-naphthoxy)-2-hydroxypropionaldehyde N-isopropylnitrone (2), and N-nitrosopropranolol (3) were prepared and tested . N-Hydroxypropranolol (1) was obtained by direct alkylation of 3-(1-naphthoxy)-1-bromo-2-propanol with N-isopropylhydroxylamine and isolated as its neutral oxalate or HBr salt . The aldonitrone (2) was obtained by mercuric oxide oxidation of the hydroxylamine . N-Nitrosopropranolol (3) was prepared by treating propranolol with nitrous acid . None of the compounds was mutagenic in the Ames assay with Salmonella typhimurium TA-98 and TA-100 strains, either in the absence or in the presence of the S-9 liver fraction from Arochlor 1254 treated rats . None of the compounds was significantly toxic to the bacteria, except for slight toxicity of the oxalate salt of 1. Biochem Biophys Res Commun, 1983 Feb 28, 111(1), 346 - 51 Possible role of DT-diaphorase in the bioactivation of antitumor quinones; Talcott RE et al.; Menadione derivatives that are toxic to tumor cells are believed to be reduced intracellularly to species that react with DNA . In this communication, we report evidence that one of these derivatives, 3-bromomethylmenadione, is reduced by DT-diaphorases present in rat liver cytosol and in rat 9L brain tumor cells . Dicoumarol, an inhibitor of DT-diaphorases was found to inhibit both the reduction of 3-bromomethylmenadione and its mutagenicity to Salmonella typhimurium TA 97 . Homogenates of rat 9L cells were found to contain relatively high levels of DT-diaphorase, suggesting that these tumor cells may be relatively sensitive to antitumor quinones that are activated by this enzyme. Anal Biochem, 1983 Feb 15, 129(1), 1 - 13 Complete analysis of tRNA-modified nucleosides by high-performance liquid chromatography: the 29 modified nucleosides of Salmonella typhimurium and Escherichia coli tRNA; Buck M et al.; A high-performance liquid chromatography (HPLC) method has been developed to quantify the major and modified nucleoside composition of total, unfractionated transfer RNA . The method is rapid and sensitive and offers a high degree of chromatographic resolution suitable for quantifying both stable and unstable modified nucleosides . It is nondestructive and allows the recovery of nucleosides for further characterization . We apply the method in the analysis of the 29 modified nucleosides in tRNA from Salmonella typhimurium (and Escherichia coli) and show it to be useful in examining changes in the modified nucleoside content of tRNA . Such changes may be important in regulation. Biochem Biophys Res Commun, 1983 Feb 10, 110(3), 746 - 52 Species difference in the metabolic activation of phenacetin by rat and hamster liver microsomes; Nohmi T et al.; Phenacetin is mutagenic in Salmonella typhimurium TA 100 when liver 9,000 X g supernatant fractions from PCB-treated hamsters instead of rats are used . A mechanism of the species difference in phenacetin mutagenicity was investigated . By high-performance liquid chromatography analysis, it was found that phenacetin is activated to direct-acting mutagens through N-hydroxylation and deacetylation by hamster liver microsomes . Although no significant species difference was observed in N-hydroxylation, rates of deacetylation were 9 to 150 times higher in hamsters than in rats . The results indicate that the marked species difference in phenacetin mutagenicity is due to the difference in deacetylation activity between rat and hamster liver microsomes. Mutat Res, 1983 Feb, 116(2), 161 - 8 Lack of genotoxic properties of the hair-dye component N-methyl-amino-2-nitro-4-N',N'-bis-(2-hydroxyethyl)-aminobenzene, in mammalian cells in vitro, and in yeasts; Loprieno N et al.; N-Methyl-amino-2-nitro-4-N',N'-bis-(2-hydroxyethyl)-aminobenzene is a hair-dye ingredient . Its potential ability to induce gene mutations, in the yeast S . pombe and in cultured mammalian CH-V79 cells, mitotic gene conversion in the yeast S . cerevisiae, and unscheduled DNA synthesis in cultured human HeLa cells was evaluated . The chemical proved unable to induce detectable genotoxic effects according to these tests . The present data, together with others that show that the chemical is not mutagenic in Salmonella typhimurium or Drosophila, and is not clastogenic in mammalian cytogenetic assays (in vitro or in vivo), strongly support the non-genotoxicity of the chemical. J Bacteriol, 1983 Feb, 153(2), 837 - 45 Role of hypoxanthine and guanine in regulation of Salmonella typhimurium pur gene expression; Houlberg U et al.; Data are presented which indicate that the repression of pur gene expression seen after the addition of preformed purines to cultures of Salmonella typhimurium is the consequence of the presence or the formation of the purine bases, hypoxanthine and guanine . This conclusion is based on the following observations . First, it was impossible to find a correlation between the size of any individual purine nucleotide pool and the level of the first four enzymes in the de novo biosynthetic pathway . Second, adenine plus guanosine served as a perfect source of purine nucleotides, but their presence caused no repression of pur gene expression if the cells lacked purine nucleoside phosphorylase activity . This enzyme is needed to convert adenine and guanosine to hypoxanthine and guanine, but not for their conversion to nucleotides . Third, addition of guanine to a strain lacking guanine phosphoribosyltransferase (gpt) resulted in a repression of the level of the purine de novo biosynthetic enzymes, a reduction of the growth rate, and a fall in the pools of ATP and GTP . Addition of hypoxanthine to a strain lacking hypoxanthine phosphoribosyltransferase (hpt) had a similar, although weaker, effect . If the cells lacked both hypoxanthine and guanine phosphoribosyltransferases (hpt gpt), their basal level of the purine de novo biosynthetic enzymes was repressed in minimal medium . Such cells grow slower than wild-type cells and excrete purines, probably due to the inability to salvage endogenously formed hypoxanthine and guanine. J Toxicol Sci, 1983 Feb, 8(1), 15 - 24 The production of mutagens in the intestine of mice fed on a diet containing 15% sorbic acid (I); Tsuchiya T et al.; When mice were fed on a diet containing 15% sorbic acid for a period up to 6 months, ether extracts of the intestinal contents of the mice were not mutagenic with Salmonella typhimurium TA98, but the acidic components obtained by fractionating the ether extracts, showed slightly mutagenic activity with S . typhimurium TA98, and they required the addition of liver 9,000 xg supernatant fraction for mutagenic activation . These results suggested that mutagens were gradually produced in the intestine and moved into the liver where they were metabolically activated . It is possible to presume that liver carcinoma might be attributable to the production of these mutagens. Acta Pathol Microbiol Immunol Scand {B}, 1983 Feb, 91(1), 69 - 73 Bacterial hydrophobicity measured as partition of palmitic acid between the two immiscible phases of cell surface and buffer; Malmqvist T; Bacterial hydrophobicity was measured as the affinity of palmitic acid to the cell surface . Cell surface and buffer were regarded as two immiscible phases with different affinity for the fatty acid . After equilibration of the system, the partition quotient (PQ) between the two phases was calculated . The bacteria hydrophobicity was expressed as the amount of cell mass required to give a partition quotient of 10 between amount of fatty acid bound to cell surface and amount of fatty acid in buffer (PQ 10) . This system permits measurement of changes in hydrophobicity during bacterial growth as shown for Staphylococcus aureus, strain V 8 . The hydrophobicity of this bacterium increased 4-5 times during the exponential growth-phase of the culture . In the stationary growth-phase there was a loss of hydrophobicity, which continued for at least 48 hours, linearly with time . The system was also tested with a Salmonella typhimurium strain and its rough mutant . The results were consistent with findings in other test systems measuring the hydrophobicity of these bacteria. Mutat Res, 1983 Feb, 107(2), 239 - 47 Influence of conjugation reactions on the mutagenicity of aromatic amines; Hongslo J et al.; 2-Acetylaminofluorene (AAF) and 2-aminofluorene (AF), as well as their N-hydroxylated metabolites, N-OH-AAF and N-OH-AF, were studied for mutagenic effects in Salmonella typhimurium with rat- and mouse-liver S9 and microsomal subfractions in the presence of cofactors for glucuronidation and glutathione (GSH) transfer . Addition of UDPGA did not affect the mutagenicity of AAF, AF or N-OH-AAF under any experimental condition . Addition of GSH, on the other hand, markedly inhibited AAF, AF and N-OH-AAF . This seemed to be due to the direct effect of GSH, and not through an enzyme-catalyzed conjugation . Further, GSH inhibited the direct mutagenicity of N-OH-AF. Zentralbl Bakteriol Mikrobiol Hyg {A}, 1983 Feb, 253(4), 515 - 22 Competitive growth experiments with related pairs of tartrate-fermenting and tartrate-non-fermenting strains of Salmonella typhimurium: relevance to biotyping studies; Old DC et al.; For each of the isomers of tartaric acid, meso- or d- or l-, a pair of strains of Salmonella typhimurium was obtained, the one, a naturally occurring, non-fermenting strain and the other a spontaneous, tartrate-fermenting mutant derived from it . For each of the pairs of strains, competitive mixed cultures were grown from inocula of the tartrate-fermenting and tartrate-non-fermenting strains in peptone medium without or with the appropriate tartrate isomer . In each experiment, small numbers of tartrate-fermenting bacteria outgrew small or large numbers of tartrate-non-fermenting bacteria in 24 hours in tartrate-containing but not in tartrate-free peptone medium . The results of the experiments are discussed with reference to the choice of the definitive time of reading for tartrate-utilisation tests in the biotyping of S . typhimurium. Toxicology, 1983 Feb, 26(2), 155 - 60 On the mutagenicity of metabolites derived from the mushroom poison gyromitrin; von der Hude W et al.; The hepatotoxic and carcinogenic hydrazine N-methyl-N-formyl hydrazine (MFH), which is formed from the mushroom poison gyromitrin by hydrolytic cleavage in vivo and in vitro during food processing is much more mutagenic for the strain TA 100 of Salmonella typhimurium in the presence of a metabolic activation system than in its absence . On the other hand, acetylated MFH (Ac-MFH) was not mutagenic for TA 100 in both test conditions . For the strain TA 98 neither MFH nor Ac-MFH were mutagenic both with and without metabolic activation . Therefore, a metabolic conversion of the free NH2-moiety of MFH into a genotoxic metabolite of MFH is postulated. Can J Biochem Cell Biol, 1983 Feb-Mar, 61(2-3), 150 - 3 A novel phosphoprotein dependent on the bacterial phosphoenolpyruvate-sugar phosphotransferase system; Waygood EB et al.; A protein has been fond by isoelectricfocusing and autoradiography in Escherichia coli and Salmonella typhimurium which was phosphorylated by enzyme I and an histidine-containing phosphocarrier protein (HPr) of the phosphoenolpyruvate-sugar phosphotransferase system (PTS) . This protein was not factor III glc nor was it specifically induced by fructose . Its presence in soluble crude extracts was dependent upon growth conditions; however, the two bacteria had different patterns and amounts in respect to this novel protein . The protein was present in S . typhimurium SB2950 which has an extensive deletion through the pts operon, thus indicating that it must be coded for elsewhere on the genome. J Gen Microbiol, 1983 Feb, 129 (Pt 2), 321 - 35 Transduction of Escherichia coli trp genes in Salmonella typhimurium and effect of N-methyl-N'-nitro-N-nitrosoguanidine on transduction with heterogenotic DNA; Mergeay M et al.; P1Kc-mediated transduction of Escherichia coli trp genes occurred at a frequency of about 10(-8) in Salmonella typhimurium trp strains carrying mutations determining sensitivity to P1 and a low level of restriction enzymes . Heterospecific transductants were analysed by using them as donors in second-stage transductions mediated by bacteriophage KBint . One class of heterospecific transductants had the phenotype Trp+ Pro- but were extremely unstable and reverted at high frequency (up to 80%) to the parental phenotype . The Trp+ Pro- phenotype probably represents insertions of the E . coli trp genes in the S . typhimurium pro genes . It was stable in a RecA background . Haploid Pl-mediated heterogenotes exhibited various degrees of homology with the trp region of S . typhimurium in KB-mediated second-stage transductions: one heterogenote (MA427), which transduced the linked markers trp, cysB and pyrF very poorly, was used to look at the effects of the mutagen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in stimulating heterologous recombination and to derive a method for positive selection of linked mutations . Following treatment with MNNG, heterospecific Trp+ transductants were obtained with MA427 as donor . Their yield was maximal immediately after MNNG treatment but decreased and even disappeared when transductions were carried out a few hours later . This transient process is thought to represent MNNG-induced conversion of abortive transductants to complete transductants . On the other hand, phenotypic analysis of MNNG-induced Trp+ heterologous transductants revealed the presence of mutations of various phenotypes . In particular, the antimutator phenotype was recognized in 15 clones among 110 MNNG-induced recombinants tested . However, most of these mutations seemed not to influence heterologous recombination. Gann, 1983 Feb, 74(1), 51 - 9 In vitro metabolic activation of N,N-dibutylnitrosamine in mutagenesis; Suzuki E et al.; Enzymatic alpha-hydroxylation is believed to be the initial step in the metabolic activation of mutagenic and carcinogenic nitrosamines . Oxidative in vitro metabolism of N,N-dibutylnitrosamine (DBN) by hepatic microsomal fractions prepared from rats treated with phenobarbital and polychlorinated biphenyl (PCB) was investigated . Following incubation of DBN with the microsomal fractions, N-butyl-N-(3-hydroxybutyl)nitrosamine was identified by gas-liquid chromatography as the principal metabolite with the N-nitroso moiety, and butyraldehyde and/or two isomeric butyl alcohols (n- and sec-) were also identified and determined by gas-liquid chromatography and high-pressure liquid chromatography . The latter compounds originate from the unstable alpha-hydroxylated intermediate, N-butyl-N-(1-hydroxybutyl)nitrosamine, by spontaneous decomposition . An increased production of butyraldehyde with a concomitant enhancement of the mutagenicity of DBN toward Salmonella typhimurium TA1535 was observed when microsomes prepared from phenobarbital- and PCB-treated rats were used . SKF 525-A not only inhibited the mutagenic activation of DBN by microsomes from rats treated with the inducers but also selectively inhibited the formation of butyraldehyde and butyl alcohols from DBN . These results indicate that among the four initial hydroxylations (alpha, omega-2, omega-1, and omega) of the butyl chain demonstrated in the metabolism of DBN, alpha-hydroxylation is primarily involved in the mutagenic activation. Zh Mikrobiol Epidemiol Immunobiol, 1983 Feb, (2), 52 - 6 {Comparative evaluation of biological properties of Salmonella typhimurium strains of different origin and genetic nature of resistance to antibiotics}; Belova TN et al.; The results obtained in the comparative study of the biological characteristics of Salmonella typhimurium strains of different origin are presented . The circulation of two biovariants differing in a number of biological characteristics, mainly in their susceptibility to antibiotics, has been shown . R-plasmids, mostly with the markers of resistance to tetracycline and with a molecular weight of 64 Md, have been isolated from "hospital" and "sporadic" strains possessing multiple antibiotic resistance. Infect Immun, 1983 Feb, 39(2), 659 - 65 Acute iron overload in mice: pathogenesis of Salmonella typhimurium infection; Sawatzki G et al.; The bacterial growth in the tissues of C3D2F1 male mice was measured during an experimental infection with two Salmonella typhimurium strains (high virulence, strain 2386/74; low virulence, strain L15403) . This experimental model was used for evaluation of the pathogenesis in normal and iron-overloaded animals . Acute iron overload was accomplished by intramuscular injections of chelated iron (with 2,3-dihydroxybenzoic acid and citrate) with a single dose of 100 micrograms of iron per mouse . Bacteria were given intraperitoneally 1 h after the iron injection . Serum iron levels, transferrin levels, and the bacteria counts in blood and liver were measured simultaneously in all animals . There was a significant increase of bacterial growth in all tissues in the iron-treated animals . Iron abolished the normal clearance of the bacteria with low virulence from the blood . This study demonstrates that a general iron overload, as determined by an increased serum iron level, resulting from preinjection of iron, enhances bacterial growth. Mutat Res, 1983 Feb, 119(2), 89 - 93 Toxic and mutagenic effects of formaldehyde in Salmonella typhimurium; Temcharoen P et al.; Toxic and mutagenic activities of formaldehyde were studied in Salmonella typhimurium strain TM677, using forward mutation to 8-azaguanine (8-AG) resistance both in the absence and in the presence of Aroclor-induced rat-liver postmitochondrial supernatant (PMS) . The results showed that formaldehyde was toxic and mutagenic to the bacteria in both systems, but toxicity and mutagenicity were reduced in the presence of PMS . The minimum concentration required to induce toxicity and mutagenicity was 0.17 mM in the absence of PMS and 0.33 mM in the presence of PMS. Mutat Res, 1983 Feb, 116(2), 91 - 102 Mutagenicity of substituted phenanthrenes in Salmonella typhimurium; LaVoie EJ et al.; An extensive series of alkylated phenanthrenes was assayed for mutagenic activity in Salmonella typhimurium TA98 and TA100 . Among the alkylated phenanthrenes assayed, 1-methylphenanthrene, 9-methylphenanthrene, 1,4-dimethylphenanthrene and 4,10-dimethylphenanthrene were active as mutagens . These studies suggest that the structural requirements favoring mutagenic activity among alkylated phenanthrenes are inhibition of 9,10-dihydrodiol formation and the presence of an unsubstituted angular ring adjacent to a free peri position . The mutagenic activities of 9-fluoro-, 9-chloro-, and 9-bromo-phenanthrene were also evaluated . The positive mutagenic response of these halogenated phenanthrenes further supports the observation that inhibition of 9,10-dihydrodiol formation among substituted phenanthrenes favors mutagenic activity. Mutat Res, 1983 Feb, 116(2), 83 - 90 Mutagenicity in Salmonella typhimurium mutants of serum extracts from airborne particulates; Ohsawa M et al.; Airborne particulates collected from urban and non-urban air were extracted with calf serum or benzene, and their mutagenic potencies were evaluated in the Salmonella reversion assay . The serum extracts were mutagenic to strains TA98 and TA100 and contained both direct- and indirect-acting mutagens . Mutagenic activities for TA98 recovered from the particulates by serum or benzene extraction were much less in the serum extracts than in the benzene extracts . There was no significant difference in mutagenic potencies of the extracts between the urban and non-urban particulates, irrespective of the presence of S9 mix . The calculated mutagenic activities per m3 of air, however, were greater for urban air than for non-urban air, because of higher concentration of particulates in urban air than in non-urban air . Serum effectively reduced both direct and indirect mutagenic activities of the benzene extracts except for an insufficient reduction in direct mutagenicity at a high dose of benzene extracts . These findings suggest that serum could contribute greatly to decrease the mutagenicity of airborne particulates by mechanisms such as less efficient solubilization of mutagenic components and inactivation by protein binding . Biological availability of mutagens, therefore, should be considered for evaluation of actual mutagenic hazard by airborne particulates. Mutat Res, 1983 Feb, 116(2), 155 - 9 Mutagenic evaluation of the monocyclic aromatic amine N-methylamino-2-nitro-4-N', N'-bis(2-hydroxyethyl)-aminobenzene in the Salmonella typhimurium/mammalian microsome test; Shahin MM et al.; The hair-dye component N-methylamino-2-nitro-4-N', N'-bis(2-hydroxyethyl) aminobenzene was investigated for mutagenic activity in Salmonella typhimurium strains TA1535, TA100, TA1537, TA1538 and TA98 . The testing was performed in the absence and in the presence of a rat-liver microsomal activation system induced by Aroclor 1254 . Our results indicate that N-methylamino-2-nitro-4-N', N'-bis(2-hydroxyethyl)aminobenzene does not induce mutations in Salmonella typhimurium strains, either in the absence or in the presence of the metabolic activation system . The purity of the compound was controlled by utilizing high-pressure liquid chromatography (HPLC) and thin-layer chromatography (TLC). Mutat Res, 1983 Feb, 116(2), 103 - 17 Mutagenic activities of gentisin and isogentisin from Gentianae radix (Gentianaceae); Morimoto I et al.; The mutagenic activities of 2 hydroxyxanthones, gentisin and isogentisin, obtained from the methanol extract of Gentianae radix (Gentianaceae) were investigated . The methanol extract of Gentianae radix, which showed mutagenicity in the Ames test in Salmonella typhimurium strain TA100 with S9 mix, was fractionated by column chromatography on Sephadex LH-20, and the fractions were purified by preparative TLC and column chromatography on polyamide . 2 mutagenic materials thus obtained, S1 and S2, each gave a single band on TLC . Identification of S1 and S2 was accomplished by comparing the analytical (mps, elementary analyses) and spectral (UV, IR, mass, NMR) results for S1 and S2 with literature data for gentisin and isogentisin . At doses below 10 micrograms, S1 (gentisin) and S2 (isogentisin) had similar specific mutagenic activities . At doses of over 10 to 50 micrograms, the mutagenic activities of S2 and S1 were 19.1 and 6.94 revertants per microgram respectively . This much lower activity of S1 than S2 may be a result of its poor solubility owing to the presence of the OMe group at C-3 . The combined yield of S1 and S2 was about 76 mg (40 mg as S1 and 36 mg as S2), which accounted for 76% of the content of mutagenic compounds (100 mg) estimated roughly from the total mutagenic activity in the extract of the starting materials (100 g). Mutat Res, 1983 Feb, 113(1), 13 - 9 The effect of different genetic properties of Salmonella typhimurium on the determination of stabilities and mutagenic concentrations of chemical carcinogens using the diffusion bioassay; Awerbuch TE et al.; The mathematical model used to calculate half-life and mutagenic concentrations of chemical carcinogens from the diffusion bioassay does not include any terms related to the nature of the microorganism used in the assay (Awerbuch et al., 1979; Awerbuch and Sinskey, 1980) . In this work we tested the model with different strains of Salmonella typhimurium . These strains are auxotrophs for histidine and are sensitive to base-pair substitution . The half-life (tau 1/2) of N-methylN'-nitro-N-nitrosoguanidine (NG) was calculated by the diffusion assay, using strains hisG46, TA1950, TA1535 and TA100 as the bacterial indicators . For all strains tau 1/2 equalled 2.2 h; strain sensitivity for detecting threshold mutagenic concentrations of NG was essentially the same, except that hisG46 was slightly more sensitive. J Infect Dis, 1983 Feb, 147(2), 210 - 6 A hospital outbreak of multiresistant Salmonella typhimurium belonging to phage type 193; Robins-Browne RM et al.; An outbreak of nosocomial infection was caused by strains of Salmonella typhimurium phage type 193 that were resistant to ampicillin, chloramphenicol, neomycin-kanamycin, streptomycin, spectinomycin, sulfonamides, tetracyclines, trimethoprim, and nalidixic acid . Resistances to drugs other than nalidixic acid were specified by plasmids, and, on the basis of phage typing and plasmid characterization studies, the multiresistant phage type 193 strains were determined to be clonal . In a two-year period, 488 patients infected with these bacteria were identified . An investigation in a pediatric surgical ward, where the outbreak was particularly severe, showed that patients exposed to antibiotics were more likely to be colonized with the epidemic strain and that young debilitated patients were more liable to show clinical signs of infection . Epidemiologic studies suggested that cross infection via the hands of the ward staff was the likely means of propagation of the epidemic. J Hyg (Lond), 1983 Feb, 90(1), 55 - 60 Plasmid-encoded trimethoprim resistance in salmonellas isolated in Britain between 1970 and 1981; Threlfall EJ et al.; Trimethoprim resistance was plasmid-encoded in all trimethoprim-resistant Salmonella typhimurium and in the majority of trimethoprim-resistant salmonellas of other serotypes isolated since 1970 from humans and food animals in Britain . In S . typhimurium, non-autotransferring plasmids of compatibility group 3 and autotransferring plasmids of group H2 predominated . The predominance of these plasmid types has resulted from the spread of clones of trimethoprim-resistant strains of phage types 18, 170 and 204c . In other salmonellas, a variety of plasmid compatibility groups have been identified . Almost all plasmids which conferred resistance to trimethoprim also coded for sulphonamide resistance. J Bacteriol, 1983 Feb, 153(2), 998 - 1007 Regulation of Escherichia coli aspartate transcarbamylase synthesis by guanosine tetraphosphate and pyrimidine ribonucleoside triphosphates; Turnbough CL Jr; The effects of guanosine tetraphosphate (ppGpp) and pyrimidine ribonucleoside triphosphates on Escherichia coli aspartate transcarbamylase (ATCase) synthesis were examined . To determine the effect of ppGpp, a stringent (relA+) and relaxed (relA) isogenic pair of E . coli K-12 strains was starved for isoleucine, and the residual rate of synthesis of this enzyme was measured . It was necessary to starve the strains for uracil before the isoleucine limitation to maintain similar, low levels of UTP, the putative pyrimidine effector of ATCase synthesis . The isoleucine starvation of the stringent strain caused an immediate 10-fold increase in the intracellular concentration of ppGpp, which was coincident with the cessation of the synthesis of the enzyme . The elevated level of ppGpp then decayed until it reached an intracellular concentration similar to that found in unstarved cells . Enzyme synthesis resumed at this time . In the relaxed strain, the intracellular concentration of ppGpp did not increase upon isoleucine starvation and synthesis of the enzyme was not repressed . These experiments strongly indicated that ppGpp acts as a negative effector of ATCase synthesis . The repression of ATCase synthesis by ppGpp was demonstrated directly by using a Salmonella typhimurium (relA) in vitro coupled transcription-translation system with a lambda specialized transducing phage carrying the E . coli K-12 operon encoding the subunits of this enzyme (pyrBI) as a source of DNA . This in vitro system was also used to measure the effects of UTP and CTP on ATCase synthesis . Increasing the concentration of UTP in the in vitro reaction mixture resulted in strong repression of this synthesis, whereas increasing the CTP concentration did not affect synthesis significantly . Possible mechanisms for the regulation of pyr gene expression, including attenuation control, are discussed. J Immunol, 1983 Feb, 130(2), 903 - 7 Natural and antibody-dependent cell-mediated activity against Salmonella typhimurium by peripheral and intestinal lymphoid cells in mice; Nencioni L et al.; Cell-mediated immune responses were assessed employing a 2-hr in vitro cytotoxicity assay against S . typhimurium . It was observed that lymphocytes from GALT as well as from peripheral lymphoid organs possessed natural antibacterial activity, whereas macrophages were devoid of this spontaneous activity . The distribution of this newly described natural activity was PPL greater than MnL greater than IEL = SpL = PBL greater than PoL; this did not correlate with the organ distribution of NK activity against YAC-1 tumor cells, which was PBL greater than SpL = IEL greater than MnL = PoL = PPL . Moreover, the phenotype of the splenic effector cell of the natural activity against S . typhimurium showed some differences from that of NK activity . In fact, both these cells were asialo GM1+, Fc-receptor+, nonadherent, and nonphagocytic, but the former was Thy-1.2- and the latter Thy-1.2+ . The effector cell of the natural antibacterial activity in the Peyer's patches had the same phenotype as the splenic one . It was then observed that the antibacterial activity could be augmented by the addition of immune antibodies against S . typhimurium . This was particularly evident employing IEL, SpL, and PBL as effector cells, whereas PPL and MnL did not show any antibody-dependent antibacterial activity . Furthermore, these last two populations could not mediate ADCC against CRBC . Employing selective methods to deplete cell populations, we observed that, at least at the splenic level, there is also a cell that differs in its phenotypic characteristics from that mediating natural antibacterial activity but that plays a role in the antibody-dependent reactions . In conclusion, these results suggest that natural and antibody-dependent antibacterial mechanisms might be important in defense against S . typhimurium, particularly at the gastrointestinal level, where many bacterial infections first take place and begin to interact with the host immune system. Cancer Res, 1983 Feb, 43(2), 653 - 9 Mutagenic response of Ames strains cured of their inducible Fels 1 and Fels 2 prophages; Affolter M et al.; Ames strain TA100 was cured of its Fels 1 and Fels 2 prophages to yield the corresponding nonlysogenic derivative designated TAQ100 . The two monolysogenic strains corresponding to TA100 lysogenic for Fels 1 (TAQ100F1) and for Fels 2 (TAQ100F2) were also isolated . In addition, the equivalent strains lacking pKM101 and designated TAQ1535, TAQ1535F1, and TAQ1535F2 were obtained . Ames strains TA98 and TA1538 are lysogenic for Fels 2 and were observed by colony hybridization to contain cryptic Fels 1 DNA sequences . Strains corresponding to TA98 and TA1538 cured of Fels 2 were isolated and designated TAQ98F1d and TAQ1538F1d, respectively . Fels 1 grew poorly on Fels 1-cured strains, and Fels 2 grew not at all on Fels 2-cured strains . The cured strains had therefore to be identified as such by their failure to react in colony hybridization with 32P-labeled probes of Fels 1 and/or Fels 2 DNA . The specificity of the labeled probes was confirmed with the aid of the nonlysogenic Salmonella typhimurium strain Q1 and its two monolysogenic derivatives Q1 (Fels 1) and Q1 (Fels 2) . The cured strains were found to respond in the same manner as did the standard Ames strains to a variety of well-known mutagens, including aflatoxin B1, 7, 12-dimethylbenz(a)anthracene, daunorubicin, 2-amino-dipyrido{1,2-a:3',2'-d}imidazole, and beta-naphthylamine . Also, mitomycin C, bleomycin, and diethylstilbestrol were nonmutagenic to TAQ100 and TAQ98F1d as they are to TA100 and TA98 . Since the Fels prophages are inducible by aflatoxin B1, by daunorubicin, and by other agents, it seems that mutagenesis and Fels prophage induction occur in separate subpopulations of cells; this situation had previously been reported to occur for mutagenesis and prophage lambda induction in Escherichia coli . In any case, the Fels prophages appear to have no major influence on the mutagenic response of the Ames strains. J Bacteriol, 1983 Feb, 153(2), 830 - 6 Genetic map of the opp (Oligopeptide permease) locus of Salmonella typhimurium; Higgins CF et al.; The uptake of peptides by Salmonella typhimurium is mediated by three apparently independent transport systems . One of these systems, the oligopeptide permease, is encoded by a genetic locus (opp) which has been mapped at 34 min on the S . typhimurium chromosomal map . We accurately mapped the location of opp by cotransduction frequencies and by deletion analysis and show that the gene order for this region of the chromosome is cysB-trp-tonB-opp-galU-tdk . All opp mutants, independently isolated by a variety of means, mapped at this one locus, between tonB and galU . Spontaneous and transposon Tn10-generated deletions were used to construct a fine-structure genetic map of opp . Evidence is presented which indicates that opp covers a 5- to 6-kb segment of DNA and is therefore likely to consist of more than one gene. J Bacteriol, 1983 Feb, 153(2), 1114 - 9 Internal promoters of the his operon in Salmonella typhimurium; Schmid MB et al.; Two internal promoters in the his operon of Salmonella typhimurium have been precisely mapped genetically . The internal promoters are found in, or very close to, gene border regions in the his operon . The his operon was examined for the presence of additional internal promoters whose transcripts were sensitive to rho-mediated transcription termination and therefore had escaped detection . No new internal promoters were found . It is argued that the internal promoters described here are not likely to be fortuitous message start sites, but may play a physiologically important role in operon expression. Zh Mikrobiol Epidemiol Immunobiol, 1983 Feb, (2), 84 - 6 {Characteristics of hydrolysis of lipopolysaccharide and Boivin antigen isolated from Salmonella typhimurium}; Iankina NF et al.; The work deals with the isolation of serologically active polysaccharide from S . typhimurium 415 . Particular attention is paid to different conditions for the hydrolysis of lipopolysaccharide (LPS) and Boivin's antigen, permitting the authors to obtain polysaccharides with different activity of the determinant groups . The action of 1% acetic acid on LPS, lasting for several hours, did not result in the hydrolysis of the antigen, while its hydrolysis in 1.5% acetic acid led to the decomposition of the greater part of the determinant groups . Polysaccharide isolated from Boivin's antigen after hydrolysis in 1% acetic acid retained the specific activity of all antigenic determinants of the natural biopolymer. J Mol Biol, 1983 Jan 25, 163(3), 377 - 94 Transcription attenuation is the major mechanism by which the leu operon of Salmonella typhimurium is controlled; Searles LL et al.; Three mutations, each causing constitutive expression of the Salmonella typhimurium leu operon, were cloned into phage vector lambda gt4 on EcoRI DNA fragments carrying all of that operon except for part of the promoter-distal last gene . Sequence analysis of DNA from these phage demonstrated that each contains a single base change in the leu attenuator . Transcription of mutant DNA in vitro resulted in transcription beyond the usual site of termination . The level of beta-IPM dehydrogenase, the leuB enzyme, was elevated 40-fold in a strain carrying one of these mutations, and starvation of this strain for leucine had little effect on the amount of activity expressed . Using a strain with a wild-type promoter-leader region of the leu operon, the rates of synthesis and degradation of leu leader RNA and readthrough RNA (leu mRNA) were measured by DNA-RNA hybridizations with specific DNA probes . The rate of synthesis of the leu leader was about the same in cells grown with excess or with limiting leucine . On the other hand, the rate of synthesis of leu mRNA was 12-fold higher for cells grown in limiting leucine as opposed to excess leucine . The rate of degradation of these RNA species was the same under both conditions of growth . Thus, the variation in expression of the leu operon observed for cells grown in minimal medium is, for the most part, not caused by control over the frequency of initiation or by the differential stability of these RNA species . Rather, the variation is a direct result of the frequency of transcription termination at an attenuator site . These results taken together suggest that transcription attenuation is the major mechanism by which leucine regulates expression of the leu operon of S . typhimurium for cells growing in a minimal medium. J Biol Chem, 1983 Jan 10, 258(1), 629 - 35 Effect of altered lipid A synthesis on the synthesis of the OmpA protein in Salmonella typhimurium; Rick PD et al.; The effect of altered lipid A synthesis on the synthesis of the OmpA protein was investigated in mutants of Salmonella typhimurium possessing a temperature-sensitive defect in 3-deoxy-D-manno-octulosonate (2-keto-3-deoxyoctonate) synthesis . The defect is due to a mutation in the structural gene for 3-deoxy-D-manno-octulosonate-8-phosphate synthetase (designated kdsA), and expression of this lesion results in the accumulation of an incomplete precursor of lipid A (Rick, P.D., and Osborn, M.J . (1977) J . Biol . Chem . 252, 4895-4903) . Pulse labeling studies revealed a pronounced transient increase in the rate of OmpA synthesis following a shift of mutants to nonpermissive conditions . The rate of OmpA synthesis increased about 2.5-fold at 20-30 min following a shift to 42 degrees C and then decreased over the next 30-40 min . A similar but less pronounced increase in the apparent rate of synthesis of the 34-kilodalton porin protein was also observed . In contrast, the rates of synthesis of total cell envelope protein, as well as that of the 35 and 36-kilodalton porin proteins, were relatively unaffected . The effect of increased temperature on the rate of OmpA synthesis was specifically related to expression of the kdsA lesion; it was not found to be strain-specific or uniquely related to expression of a single kdsA mutant allele. FEBS Lett, 1983 Jan 10, 151(1), 59 - 62 Cyclic AMP-independent phosphorylation of Escherichia coli isocitrate dehydrogenase; Malloy PJ et al.; The phosphorylation of NADP-specific isocitrate dehydrogenase in a wild-type and in an adenylate cyclase deletion mutant of Escherichia coli has been investigated . The results obtained clearly indicate that cyclic AMP is not required for the phosphorylation reaction per se, not is it for the synthesis or possible activation of the phosphoprotein kinase in this organism . This data are in contrast to results observed in Salmonella typhimurium, and indicate that important differences exist in the phosphorylation of the isocitrate dehydrogenase in these two organisms. J Gen Virol, 1983 Jan, 64 (Pt 1), 199 - 205 Genetic studies of hybrids between coliphage phi 80 and Salmonella phage P22; Yamamoto N et al.; Hybrids between Escherichia coli phage phi 80 and Salmonella typhimurium phage P22 were isolated after superinfection by P22 of a smooth E . coli-S . typhimurium hybrid lysogenic for phi 80 . These hybrid phages, designated phi 80immP22 and phi 80immP22dis, possessed the phi 80 protein coat and tail genes . The phi 80immP22 hybrids acquired the immunity (immC) region of P22 and some adjacent P22 genes, but E . coli-S . typhimurium strains lysogenic for phi 80immP22 hybrids remained sensitive to P22 . The phi 80immP22dis hybrids, found ten times more frequently than the phi 80immP22 hybrids, contained a more extensive portion of the P22 genome which encompassed the immI as well as the immC region of P22 . Therefore, the phi 80immP22dis hybrids conferred on their hosts immunity to P22 infection . Further analyses have revealed that the phi 80immP22dis hybrids carry the P22 attachment region and either P22 tail gene 9 or antigen conversion gene a1, but not both of these genes. Prog Food Nutr Sci, 1983, 7(3-4), 19 - 28 Survival rate of Salmonella and Shigella in fermented milk products with and without added human gastric juice: an in vitro study; Alm L; The survival rates of Salmonella agona, Salmonella java, Salmonella typhimurium and Shigella sonnei in milk and fermented milk products were investigated with and without the addition of human gastric juice during a 7 to 10 hour test period . It was found that yoghurt inhibited the growth of Salmonella and Shigella very effectively even when the yoghurt had been heated to 100 degrees C for 15 minutes, whereas milk and the other fermented milk products showed a lower ability to inhibit the growt