C R Seances Acad Sci III, 1982 Sep 27, 295(3), 181 - 4 {Mutagenic effect of photoactivated methoxylated derivatives of 2-nitronaphtho (2.1-b) furan on the yeast Saccharomyces cerevisiae}; Averbeck D et al.; 2-nitro 7-methoxy naphtho {2,1-b} furan (R 7000) and 2-nitro 8-methoxy naphtho {2,1-b} furan, which are highly mutagenic on the bacterium Salmonella typhimurium have little activity on the yeast Saccharomyces cerevisiae . Nevertheless, irradiation at 365 nm elicits a weak but significant increase of their mutagenic activity on this yeast. J Biol Chem, 1982 Sep 10, 257(17), 9915 - 8 Extensive homology between membrane-associated components of histidine and maltose transport systems of Salmonella typhimurium and Escherichia coli; Gilson E et al.; A strong homology was found between the amino acid sequences, deduced from DNA nucleotide sequences, of cytoplasmic membrane-associated components of the high affinity histidine transport system of Salmonella typhimurium (coded by the hisP gene) and the maltose-maltodextrin transport system of Escherichia coli (coded by the malK gene) . When the HisP protein sequence was aligned with that of the NH2-terminal two-thirds of the MalK protein, 32% of the positions were identical, and an additional 35% were occupied by functionally similar amino acid residues . These results suggest that some, and possibly many, "periplasmic-binding protein-dependent" transport systems have evolved from a common ancestral system. J Bacteriol, 1982 Sep, 151(3), 1433 - 43 A third L-proline permease in Salmonella typhimurium which functions in media of elevated osmotic strength; Csonka LN; Exogenous proline specifically stimulates the growth rate of enteric bacteria in media of inhibitory osmotic strength (J . H . B . Christian, Aust . J . Biol . Sci . 8:490-497, 1955) . I observed that Salmonella typhimurium mutants which lack both of the previously known proline permeases (putP proP) are stimulated by proline in media of inhibitory osmolarity . I propose that there is a third proline permease which functions only in media of elevated osmolarity . This conclusion is based on the observations that, in media of elevated osmolarity, (i) the sensitivity of putP proP mutants to toxic proline analogs increases, (ii) proline requirements for maximal growth of proline auxotrophic putP proP mutants decreases, and (iii) the specific rate of incorporation of radioactive proline into protein of growing cells increases . I obtained a Tn10-induced mutation in a gene (proU) required for the functioning of the third proline permease and determined the map location to be at 59 map units of the chromosome, between srlA and tct, 66% linked to nalB in P22 transduction . My results suggest that the function of the third, osmotically stimulated permease might be to accumulate high intracellular proline levels during osmotic stress . Possible mechanisms by which proline might cause growth stimulation are discussed. Proc Natl Acad Sci U S A, 1982 Sep, 79(17), 5122 - 6 Mechanism of the inhibition of mutagenicity of a benzo{a}pyrene 7,8-diol 9,10-epoxide by riboflavin 5'-phosphate; Wood AW et al.; Riboflavin 5'-phosphate (flavin mononucleotide; FMN) inhibits the mutagenicity of (+/-)-7 beta, 8 alpha-dihydroxy-9 alpha, 10 alpha-epoxy-7,8,9,10-tetrahydrobenzo{a}pyrene (B{a}P diol epoxide), the only known ultimate carcinogenic metabolite of benzo{a}pyrene . Coincubation of 10, 25, and 50 nmol of FMN with strain TA100 of histidine-dependent Salmonella typhimurium inhibits the mutagenicity of 0.05 nmol of the diol epoxide by 50, 70, and 90%, respectively . Ribose 5-phosphate and riboflavin show no significant effects at comparable doses . Reaction of B{a}P diol epoxide with FMN in aqueous solution at neutral pH produces only tetraols, with no evidence for covalent adducts . At pH 7 the rate of hydrolysis of B{a}P diol epoxide in dioxane/water, 1:9 (vol/vol), at 25 degrees C is increased more than 10-fold in the presence of 100 muM FMN . Spectrophotometric studies and quantitative rate data for the reaction of the diol epoxide with FMN indicate that a complex is formed between the diol epoxide and the flavin moiety of FMN (Ke = 1,400-3,400 M-1) prior to general acid-catalyzed hydrolysis of the epoxide to tetraols by the phosphate monoanion of FMN . Comparable concentrations of ribose 5-phosphate and riboflavin do not significantly increase the rate of hydrolysis, although evidence for complex formation between riboflavin and the diol epoxide is observed . General acid-catalyzed hydrolysis of bay-region polycyclic hydrocarbon diol epoxides by compounds that have a high affinity for these ultimate carcinogens represents a potentially useful way of inhibiting their carcinogenic activity. Toxicol Lett, 1982 Sep, 13(1-2), 1 - 5 Mutagenicity of 2,4-dinitrotoluene and its metabolites in Salmonella typhimurium; Mori MA et al.; 2,4-Dinitrotoluene (2,4-DNT) and its metabolites (2A4NT, 4A2NT, 2,4-DNB, 2A4NB, 4A2NB, 2,4-DAT, 2N4AAT, 2A4AAT, 2A4AABA and 2,4-DNBA), and 2,4-dinitrobenzaldehyde (2,4-DNA1), putative metabolite of 2,4-DNT, were tested for mutagenicity in Salmonella typhimurium strains TA98 and TA100 . 2,4-DAT, 2N4AAT, 2A4AAT, 2A4AABA and 2,4-DNBA were inactive for strains TA98 and TA100 . 2,4-DNT itself was only a weak mutagen . Two aminonitrotoluenes (2A4NT and 4A2NT), two aminonitrobenzyl alcohols (2A4NB and 4A2NB) and 2,4-dinitrobenzyl alcohol (2,4-DNB) were increasingly mutagenic in that order, in both strains, however, they were only weak or weak mutagens at mM concentrations . In contrast with these compounds, 2,4-DNA1 was mutagenic even at microM concentrations in both strains . These results suggest that a high mutagenicity of 2,4-DNA1 may be correlated to the carcinogenicity of 2,4-DNT. Zh Mikrobiol Epidemiol Immunobiol, 1982 Sep, (9), 53 - 7 {Comparative study of Salmonella typhimurium strains of various origins in murine models of enteral and intranasal infection}; Iakovleva ON et al.; Antibiotic-resistant S . typhimurium strains of different origin (isolated from patients in cases of hospital infections and enteral toxico-infections, as well as from water), when studied in experimental enteral and intranasal infection of mice showed, in comparison with antibiotic-sensitive strains, less pronounced lethal action and, accordingly, lower capacity for reproduction in the organs of the reticulo-endothelial system of mice . Multiresistant strains isolated from humans in enteral toxico-infections kill orally infected mice more frequently than strains isolated in hospital infections. Can J Microbiol, 1982 Sep, 28(9), 993 - 1001 Involvement of plasmids in determining bacteriophage sensitivity in Salmonella typhimurium: genetic and physical analysis of phagovar 204; Bezanson G et al.; Strains resistant to the action of sulfa drugs and tetracycline were predominant among the antibiotic-resistant Salmonella typhimurium phagovar 204 isolated in Canada . Plasmid DNA was detected in cellular extracts of all strains examined . A number of these plasmids could be placed in specific incompatibility and size classes . Both resistance coding and cryptic plasmids were involved in determining phagovar 204 . In one instance, phagovar 204 was derived from phagovar 36 in a two-step conjugation involving independent sulfadiazine and tetracycline resistance plasmids . In another, phagovar 204 was derived directly from phagovar 49 through the introduction of a single tetracycline-streptomycin R plasmid . The phagovar-determining plasmids ranged in size from 3.4 to 72 megadaltons. Proc Natl Acad Sci U S A, 1982 Sep, 79(17), 5175 - 8 Aminofluorene-DNA adduct formation in Salmonella typhimurium exposed to the carcinogen N-hydroxy-2-acetylaminofluorene; Beranek DT et al.; The DNA adducts formed during incubation of the hepatocarcinogen N-hydroxy-2-acetylaminofluorene with Salmonella typhimurium tester strain TA1538 were investigated to determine if the covalently bound products were identical to those adducts found in rat liver DNA and to establish the biological significance of the adducts in a mutational assay . When bacteria were exposed to N-hydroxy-2-acetylaminofluorene in the presence of a 9,000 x g supernatant from a rat liver homogenate (S9), only one adduct was detected . This adduct had chromatographic, pH-dependent partitioning, and UV spectral characteristics identical to those of N-(deoxyguanosin-8-yl)-2-aminofluorene . In the absence of S9 activation the same product was detected, but at a 85-90% lower level, which indicates that S . typhimurium also may be capable of metabolizing N-hydroxy-2-acetylaminofluorene to a reactive electrophile . When incubations were conducted with N-hydroxy-2-aminofluorene in the absence of the activation system, N-(deoxyguanosin-8-yl)-2-aminofluorene again was the major adduct . At equimolar concentrations, the arylhydroxylamine was approximately 10 times more efficient than the arylhydroxamic acid in inducing reversions in the bacteria . Comparison of the mutation rate to the level of binding in bacterial DNA gave a linear relationship with a slope of 0.96 and a correlation coefficient of 0.92 . These data support previous suggestions that N-hydroxy-2-acetylaminofluorene is deacetylated by rat liver S9 to the ultimate mutagen, N-hydroxy-2-aminofluorene, and also indicate that S . typhimurium can mediate this reaction . The correlation between mutagenicity and the extent of N-(deoxyguanosin-8-yl)-2-aminofluorene adduct formation, coupled with the observation that this adduct is the major DNA adduct found in rat liver in vivo, suggests that N-(deoxyguanosin-8-yl)-2-aminofluorene may be a critical lesion for the initiation of hepatic tumorigenesis. Infect Immun, 1982 Sep, 37(3), 935 - 9 Requirement for an additional serum factor essential for the antibody-independent activation of the classical complement sequence by Gram-negative bacteria; Clas F et al.; Killing of Salmonella minnesota and Salmonella typhimurium S and R strains in serum of nonimmune humans and guinea pigs was drastically reduced in the selective absence of C1q, C1r, Ca2+, C4, or C2, the components of the classical complement pathway . Binding of C1 and C1q to the S form and six different core-deficient R mutant strains became stronger the shorter the lipopolysaccharide molecule . C1 and C1q had, under physiological conditions, no affinity to the serum-resistant S forms, whereas these components were bound by the serum-sensitive R forms with high affinity . However, a mixture of the individual complement components C1-C9, which rapidly lysed sensitized erythrocytes, did not kill the serum-sensitive bacteria . Isolated C1 bound to these bacteria cleaved fluid-phase C4 but did not convert C2 . C2 turnover could be detected only when serum was used as a source of C1 or C4, indicating that an additional serum component is necessary for the antibody-independent bactericidal effect . Functional tests indicated that this factor is a euglobulin which mediates binding of C4 to the bacteria even in the absence of C1 or after treatment with EDTA . Binding of C4 followed by the generation of C4b sites as acceptors for C2 was a prerequisite for the killing of the bacteria . The factor could not be replaced by immunoglobulin G or immunoglobulin M, nor was it blocked by preincubation with anti-immunoglobulin G or anti-immunoglobulin M. Mutat Res, 1982 Sep, 96(1), 1 - 13 The mutagenicity of dibenz {a,h}anthracene activated by phenobarbital-inducible mouse-liver mono-oxygenase is potentiated by the presence of hydrophilic residues at the K-region of the molecule; Platt KL et al.; Dibenz{a,h}anthracene and synthetic K-region derivatives of the parent hydrocarbon and of benz{a}anthracene were tested for mutagenicity by the reversion of histidine-dependent Salmonella typhimurium TA98, TA100 and TA1537 . The K-region metabolite 5,6-dihydroxy-5,6-dihydrodibenz{a,h}anthracene, inactive as such, was efficiently activated to mutagens for TA98 and TA100 by mouse-liver 9000 X g supernatant or microsomal fraction . Microsomes from phenobarbital- or Aroclor-1254-treated mice were efficient for this activation, while those from untreated or beta-naphthoflavone-treated mice were much less active . A study on the influence of various structural features on this efficient activation by phenobarbital-inducible mono-oxygenase of mouse-liver microsomes showed that, if the K-region were saturated, no metabolism to mutagens occurred, while substitution of the K-region by carbonyl and hydroxyl substituents led to increased mutagenic efficacy with increasing hydrophilicity (dihydro less than carbonyl less than hydroxyl) . The K-region epoxide was the only derivative that did not require metabolic activation and it had a markedly different mutagenic specificity in that it was also mutagenic for TA1537. Immunology, 1982 Sep, 47(1), 149 - 56 Inbred mouse strain resistance to Mycobacterium lepraemurium follows the Ity/Lsh pattern; Brown IN et al.; Inbred mouse strains and their F1 hybrids infected intravenously with Mycobacterium lepraemurium showed different mean survival times (MST) . BALB/c and C57BL mice were particularly susceptible, whereas C3H, CBA and DBA/2 mice were relatively resistant . Resistance as judged by MST was dominant in the F1 hybrids . A similar ranking order was obtained by comparing the doubling time of the bacillus in the bone marrow, the increase in spleen weight between 4 and 12 weeks after infection, and the pathology of the liver during infection . The general pattern suggests that mouse resistance to M . lepraemurium is, at least in part, controlled by a gene with the same strain distribution as the genes for resistance to Salmonella typhimurium (Ity') and Leishmania donovani (Lsh') and the gene controlling resistance to Mycobacterium bovis BCG (Bcg) . Ity, Lsh and Bcg are all known to be on chromosome 1, suggesting a centre controlling reactions to intracellular infections. Res Vet Sci, 1982 Sep, 33(2), 221 - 7 Defined salmonella antigens for detection of cellular and humoral immune responses in salmonella infected calves; Robertsson JA et al.; Intracutaneous injection of a crude supernatant fraction from homogenised Salmonella typhimurium SVA 44 (O 4, 5, 12) or S dublin SVA 47 (O 9, 12) elicited highly significant (P less than 0.005) double skin-fold thickness increases in calves spontaneously infected with salmonella and verified as excretors . The use of isolated structurally defined outer membrane components from salmonella bacteria established that the delayed skin reactions could be elicited by either the lipopolysaccharide which contains O-antigenic polysaccharide chains homologous to the infecting strain, or an outer membrane protein fraction (porin) . The porin preparation gave rise to skin reactions regardless of which salmonella serotype the calf was infected with . Histological examination of biopsy material indicated a delayed skin reaction . No such reactions were seen in biopsies from control calves . The use of lipopolysaccharide permitted a salmonella serogroup specific skin test although the endotoxic side effects were marked in doses above 50 micrograms . Purified O-antigen specific polysaccharides devoid of lipid A from S typhimurium (O 4, 12) or S enteritidis (O 9, 12) failed however to elicit skin reactions . Infected calves had humoral antibody titres against the O antigen of the infecting strain which were significantly (P less than 0.005) higher than those found in control calves. J Biol Chem, 1982 Aug 25, 257(16), 9759 - 69 Complete analysis of cellular nucleotides by two-dimensional thin layer chromatography; Bochner BR et al.; We describe methods for the complete analysis of cellular nucleotides from as few as 10(6) 32Pi-labeled cells in a simple 2-day experiment . Nucleotides are extracted with acid, neutralized, and resolved by two-dimensional thin layer chromatography on polyethyleneimine cellulose . In the first dimension the nucleotides are separated based on the negative charge of their phosphate groups (i.e . cyclic, mono-, di, and triphosphates) and in the second dimension on their content of nucleobases (i.e . Ura, Cyt, Thy, Gua, and Ade) . Because the separation is logical, one can predict the chromatographic migration of most nucleotides . By running standards we have determined the chromatographic location of over 90 biologically important nucleotides, nucleotide derivatives, and modified nucleotides from tRNA . We also developed a set of enzymatic and chemical methods to be used in conjunction with the chromatographic separations for verifying the identity of nucleotides and characterizing novel nucleotides . In this paper we use these methods to analyze and inventory the nucleotide content of Salmonella typhimurium in balanced log phase growth . Other potential uses of the method are also described. Nature, 1982 Aug 19, 298(5876), 723 - 7 Complete nucleotide sequence and identification of membrane components of the histidine transport operon of S . typhimurium; Higgins CF et al.; The nucleotide sequence of the entire histidine transport operon from Salmonella typhimurium has been determined and is shown to consist of four genes, hisJ, hisQ, hisM and hisP . This operon provides the only example of a binding protein-dependent transport system for which the total number of protein components is known . Determination of the amino acid compositions and sequences of these four transport proteins, together with analysis of various transport mutants, allows us to propose a molecular model for binding protein-dependent transport. J Virol, 1982 Aug, 43(2), 529 - 32 Alteration of bacteriophage attachment capacity by near-UV irradiation; Hartman PS et al.; Near-UV (NUV) (300 to 400 nm) and far-UV (FUV) (254 nm) radiations damage bacteriophage by different mechanisms . Host cell reactivation, Weigle reactivation, and multiplicity reactivation were observed upon FUV, but not upon NUV irradiation . Also, the number of his+ recombinants increased with P22 bacteriophage transduction in Salmonella typhimurium after FUV, but not after NUV irradiation . This loss of reactivation and recombination after NUV irradiation was not necessarily due to host incapability to repair phage damage . Instead, the phage genome failed to enter the host cell after NUV irradiation . In the case of NUV-irradiated T7 phage, this was determined by genetic crosses with amber mutants, which demonstrated that either "all" or "none" of a T7 genome entered the Escherichia coli cell after NUV treatment . Further studies with radioactively labeled phage indicated that irradiated phage failed to adsorb to host cells . This damage by NUV was compared with the protein-DNA cross-link observed previously, when phage particles were irradiated with NUV in the presence of H2O2 . H2O2 (in nonlethal concentration) acts synergistically with NUV so that equivalent phage inactivation is achieved by much lower irradiation doses. J Bacteriol, 1982 Aug, 151(2), 860 - 6 Altered regulation of isoleucine-valine biosynthesis in a hisW mutant of Salmonella typhimurium; Davis L et al.; Control of isoleucine-valine biosynthesis was examined in the cold-sensitive hisW3333 mutant strain of Salmonella typhimurium . During growth at the permissive temperature (37 degrees C), the isoleucine-valine (ilv) biosynthetic enzyme levels of the hisW mutant were two- to fourfold below these levels in an isogenic hisW+ strain . Upon a reduction in growth temperature to partially permissive (30 degrees C), the synthesis of these enzymes in the hisW mutant was further reduced . However, synthesis of the ilv enzymes was responsive to the repression signal(s) caused by the addition of excess amounts of isoleucine, valine, and leucine to the hisW mutants . Such a "super-repressed" phenotype as that observed in this hisW mutant is similar to that previously shown for the hisU1820 mutant, but was different from the regulatory response of the hisT1504 mutant strain . Moreover, by the use of growth-rate-limiting amounts of the branched-chain amino acids, it was shown that this hisW mutant generally did not increase the synthesis of the ilv enzymes as did the hisW+ strain . Overall, these results are in agreement with the hypothesis that the hisW mutant is less responsive to ilv specific attenuation control than is the hisW+ strain and suggest that this limited regulatory response is due to an alteration in the amount or structure of an element essential to attenuation control of the ilv operons. Cancer Res, 1982 Aug, 42(8), 2972 - 6 Mutagenicity of the optical isomers of the diastereomeric bay-region chrysene 1,3-diol-3,4-epoxides in bacterial and mammalian cells; Wood AW et al.; The mutagenic activities of the four optically pure (+)- and (-)-enantiomers of the two diastereomeric bay-region chrysene 1,2-diol-3,4-epoxides were evaluated in histidine-dependent strains of Salmonella typhimurium and in cultured Chinese hamster V79 cells . In strain TA98 of S . typhimurium, (-)-1 alpha, 2 beta-dihydroxy-3 beta, 4 beta-epoxy-1,2,3,4-tetrahydrochrysene was 5 to 10 times more active than the other three optical isomers . However, in strain TA100 of S . typhimurium and in Chinese hamster V79 cells, (+)-1 beta, 2 alpha-dihydroxy-3 alpha, 4 alpha-epoxy-1,2,3,4-tetrahydrochrysene was the most mutagenic diol-epoxide and was from 5 to 40 times more active than the other three optical isomers . The bay-region (+)- and (-)-3,4-epoxy-1,2,3,4-tetrahydrochrysene isomers has identical mutagenic activities in all three systems . These studies indicate that the presence and orientation of the hydroxyl groups play an important role in modulating the mutagenic activity of bay-region epoxides of chrysene in both bacterial and mammalian cells. Biochimie, 1982 Aug-Sep, 64(8-9), 775 - 81 Measurement of recA protein induction in Salmonella typhimurium: a possible biochemical test for the detection of DNA damaging agents; Pierre A et al.; RecA protein was purified from S . typhimurium and its concentration was measured in crude extracts by an immunoradiometric assay . The dose-response relations and the kinetics of recA protein induction following treatment of the cells with ultra-violet light, nalidixic acid, mitomycin C, and cisplatin were studied in E . coli and S . typhimurium . The recA protein amplification was complete in a few hours and was stable for at least 3 hours . Dose-response curves showed a linear region for low doses of all the inducer agents tested . This direct relation between the recA protein level and the amount of inducer agent allows the quantification of the recA protein inducing potency of chemicals . The recA protein amplification was very sensitive to low doses of inducer agents: an UV dose of 0.25 J/M2, 500 ng of NAL or 50 ng of MMC induced a two-fold increase in cellular recA protein content . In addition, the measurement of RecA protein induction did not require the survival of the cells . These observations led us to suggest a new biochemical assay for detecting DNA damaging substances by the direct measurement of the recA protein level following treatment of the cells. J Gen Microbiol, 1982 Aug, 128 (Pt 8), 1791 - 4 Delayed inducibility of sulphite reductase in cysM mutants of Salmonella typhimurium under anaerobic conditions; Filutowicz M et al.; Salmonella typhimurium cysM mutants grow at a normal rate under aerobic conditions, but only after a lag period under anaerobic conditions . No difference in the induction of two cysteine biosynthetic enzymes--sulphite reductase and O-acetyl-L-serine sulphydrylase--in wild-type, cysK and cysM strains was observed under aerobic conditions . Under anaerobic conditions, however, the cysM strain differed from the others in showing a long delay in the induction of sulphite reductase . These observations are consistent with the assumption that the observed growth delay of the cysM mutant under anaerobic conditions is the result of abnormalities in the regulation of sulphite reductase. J Gen Microbiol, 1982 Aug, 128 (Pt 8), 1785 - 90 A new class of mutants of the cysB regulatory gene for cysteine biosynthesis in Salmonella typhimurium; Wiater A et al.; A new class of regulatory mutants in the cysB locus has been isolated by plating cysM strains, under anaerobic conditions, on medium containing 1,2,4-triazole . The isolated cysB mutants are cysteine prototrophs and triazole-resistant, although the levels of cysteine and O-acetyl-L-serine sulphydrylase are not changed . In contrast to the constitutive cysB mutants identified previously, the expression of the cysteine biosynthetic enzymes in the newly isolated mutants is regulated by the same factors as in wild-type strains . In the double mutant cysE cysB2971, the cysteine biosynthetic enzymes are absent with the exception of O-acetyl-L-serine sulphydrylase. Toxicol Lett, 1982 Aug, 12(4), 281 - 8 Experimental models for the biological detection of N-nitroso compounds formed from amines and nitrite; Baumeister M; The secondary and tertiary amines morpholine, aminopyrine and cimetidine as well as their nitroso products were examined for mutagenicity with the Ames Salmonella typhimurium microsome test (strains TA1535 and TA100) and the host-mediated assay . The formation of mutagenic nitroso compounds from morpholine and aminopyrine in the presence of nitrite could be demonstrated in artificial gastric juice and was confirmed in the stomach of mice in vivo . In contrast, the positive response of the chemical nitrosation in vitro with cimetidine did not match with the mammalian host-mediated assay results . To enhance sensitivity the role of modifiers of nitrosation, such as ascorbic acid and thiocyanate as well as the influence of biotransformation were studied. Food Chem Toxicol, 1982 Aug, 20(4), 427 - 32 Evaluation, using Salmonella typhimurium, of the mutagenicity of seven chemicals found in cosmetics; Prival MJ et al.; Six chemicals used as ingredients in cosmetics were evaluated for mutagenic activity in Salmonella typhimurium . Two of these ingredients, trans-4-phenyl-3-butene-2-one and 2,2',4,4'-tetrahydroxybenzophenone, were mutagenic in the presence of rat liver S-9 towards strains TA100 and TA1537 respectively . An impurity found in some cosmetic products, N-nitrosodiethanolamine, was mutagenic to S . typhimurium strains TA1535 and TA100 in the presence of hamster-liver S-9 but not rat-liver S-9. Food Chem Toxicol, 1982 Aug, 20(4), 383 - 91 Mutagenicity testing in the Salmonella typhimurium assay of phenolic compounds and phenolic fractions obtained from smokehouse smoke condensates; Pool BL et al.; Smokehouse smoke, which is used for flavouring meat products, was investigated for its mutagenic activity in the Salmonella typhimurium assay . We were chiefly concerned with the fractions free of polycyclic aromatic hydrocarbons but containing phenol compounds, which are responsible for the preservative and aromatizing properties of the smoke . The most abundantly occurring phenol compounds (phenol, cresols, 2,4-dimethylphenol, brenzcatechine, syringol, eugenol, vanilline and guaiacol) gave negative results when they were tested for mutagenicity at five concentrations up to 5000 micrograms/plate, with and without S-9 mix, using five strains of S . typhimurium . Even when phenol was further investigated in a variety of test conditions, no induction of his+ revertants was observed . When smokehouse smoke was condensed and fractionated the majority of the various phenolic fractions also gave negative results when tested at five concentrations using five strains of S . typhimurium . However there was a slight increase in the number of revertants in a few cases . The presence in the phenolic fractions of very small amounts of mutagenic impurities, the nature of which needs further investigation, cannot be excluded . These results support the further development of non-hazardous smoke-aroma preparations, based on the phenolic components of smokehouse smoke. Food Chem Toxicol, 1982 Aug, 20(4), 357 - 63 Mutagens from the cooking of food . II . Survey by Ames/Salmonella test of mutagen formation in the major protein-rich foods of the American diet; Bjeldanes LF et al.; The formation of mutagens in the major cooked protein-rich foods in the US diet was studied in the Ames Salmonella typhimurium test . The nine protein-rich foods most commonly eaten in the USA--ground beef, beef steak, eggs, pork chops, fried chicken, pot-roasted beef, ham, roast beef and bacon--were examined for their mutagenicity towards S . typhimurium TA1538 after normal 'household' cooking (deep frying, griddle/pan frying, baking/roasting, broiling, stewing, braising or boiling of 100-475 degrees C) . Well-done fried ground beef, beef steak, ham pork chops and bacon showed significant mutagen formation . For chicken and beef steak high-temperature broiling produced the most mutagenicity, followed by baking/roasting and frying . Stewing, braising and deep frying produced little mutagen . Eggs and egg products produced mutagens only after cooking at high temperatures (the yolk to a greater extent than the white) . Commercially cooked hamburgers showed a wide range of mutagenic activity . We conclude that mutagen formation following cooking of protein-containing foods is a complex function of food type, cooking time and cooking temperature . It seems clear that all the major protein-rich foods if cooked to a well-done state on the griddle (eggs only at temperatures above 225 degrees C) or by broiling will contain mutagens detectable by the Ames/Salmonella assay . This survey is a step towards determining whether any human health hazard results from cooking protein-rich foods . Further testing in both short- and long-term genotoxicity bioassays and carcinogenesis assays are needed before any human risk extrapolations can be made. Mutat Res, 1982 Aug, 95(2-3), 159 - 70 Metabolic activation of 2-amino-9H-pyrido{2,3-b}indole by rat-liver microsomes; Niwa T et al.; Microsomal activation was required for the expression of the mutagenicity of 2-amino-9H-pyrido{2,3-b}indole (A alpha C) toward Salmonella typhimurium TA98 . Pretreatment of rats with PCB, 3-methylcholanthrene or phenobarbital increased the mutagenic activating ability of hepatic microsomes by 16-, 10- and 2-fold, respectively, as compared with the untreated . The mutagenic activation of A alpha C by microsomes from PCB-treated rats was inhibited by ellipticine and alpha-naphthoflavone, whereas SKF 525-A and metyrapone showed a slight or no inhibitory effect, indicating that the P-448 form of cytochrome P-450 is involved in the mutagenic activation of A alpha C . Metabolic activation of A alpha C was studied by a high-performance liquid chromatography and Salmonella/microsome assay system, and the mutagenic metabolites formed were determined to be the N-hydroxy and nitroso derivatives, from the results of reaction with oxidizing or reducing agents . These results strongly indicate that N-hydroxylation of A alpha C by the P-448 type of cytochrome P-450 is essential for the mutagenic activation. Mutat Res, 1982 Aug, 95(2-3), 119 - 28 Inhibition of mutagenicity of a model nitrosation reaction by naturally occurring phenolics, coffee and tea; Stich HF et al.; Several plant phenolics, one instant coffee, one instant decaffeinated coffee, one roasted coffee, one Japanese tea, one black Indian tea, and one Chinese tea were examined for their inhibitory properties on mutagenicity resulting from the nitrosation of methylurea . Mutagenicity was estimated as the number of his+ revertants per survivor of Salmonella typhimurium TA1535 which was exposed in suspension to the nitrosation mixtures and the modulating agents for 20 min . Tannic acid, gallic acid and chlorogenic acid suppressed the mutagenicity of the model nitrosation system at concentrations similar to or even lower than ascorbic acid . The three tested coffees and three tested teas exerted an inhibitory effect on the mutagenicity of the test system at doses at which they are consumed. J Gen Microbiol, 1982 Aug, 128 (Pt 8), 1863 - 71 Mutant strains of Salmonella typhimurium with defective phosphoribosylpyrophosphate synthetase activity; Pandey NK et al.; A mutant of Salmonella typhimurium with undetectable phosphoribosylpyrophosphate (PRPP) synthetase activity in vitro and abnormally low PRPP pools in vivo was identified by screening temperature-sensitive isolates by an autoradiographic procedure . The lack of PRPP synthetase activity in vitro and temperature-sensitive growth were shown to result from separate, but closely linked mutations mapping at 47 units on the Salmonella chromosome . Mutant cell extracts prepared by a variety of methods did not show any detectable PRPP synthetase activity, but material that was immunochemically cross-reactive with PRPP synthetase was detected by complement fixation analysis . A second mutant, isolated by localized mutagenesis, contained about half the PRPP synthetase and cross-reacting material of the parental strain. Proc Natl Acad Sci U S A, 1982 Aug, 79(16), 5011 - 5 Transcriptional activity of the transposable element Tn10 in the Salmonella typhimurium ilvGEDA operon; Blazey DL et al.; Polarity of Tn10 insertion mutations in the Salmonella typhimurium ilvGEDA operon depends on both the location and the orientation of the Tn10 element . One orientation of Tn10 insertions in ilvG and ilvE permits low-level expression of the downstream ilvEDA and ilvDA genes, respectively . Our analysis of Salmonella ilv recombinant plasmids shows that this residual ilv expression must result from Tn10-directed transcription and does not reflect the presence of internal promoters in the ilvGEDA operon, as was previously suggested . The opposite orientation of Tn10 insertion in ilvE prevents ilvDA expression, indicating that only one end of Tn10 is normally active in transcribing adjacent genes . Both orientations of Tn10 insertion in ilvD exert absolute polarity on ilvA expression . Expression of ilvA is known to be dependent on effective translation of ilvD, perhaps reflecting the lack of a ribosome binding site proximal to the ilvA sequence . Therefore, recognition of the ability of Tn10 to promote transcription of contiguous genes in the ilvGEDA operon apparently requires the presence of associated ribosome binding sites. Infect Immun, 1982 Aug, 37(2), 728 - 36 Salmonella typhimurium infection in calves: specific immune reactivity against O-antigenic polysaccharide detectable in in vitro assays; Robertsson JA et al.; Peripheral blood lymphocytes collected from calves infected experimentally with Salmonella typhimurium (O antigens 4,5,12) or Salmonella sp . serotype dublin (O 9,12) were stimulated with various bacterial cell envelope components, and their {3H}thymidine incorporation was measured . It was found that peripheral blood lymphocytes from infected calves incorporated significantly more {3H}thymidine than peripheral blood lymphocytes from uninfected controls (P values ranged from less than 0.05 to less than 0.0005) . The responder cell type was found in a B-cell-depleted and T-cell-enriched population . The Salmonella infections elicited T-cell responses against at least two cell envelope components: (i) a specific response against the O-antigenic polysaccharide chain of the lipopolysaccharide (This was evident in that a polysaccharide from S . enteritidis {O 9,12} which shares a trisaccharide structure {O antigen 12 determinant} with S . typhimurium stimulated {3H}thymidine uptake, which, although lower than in the homologous system, was significantly higher than that seen after incubation with unrelated Salmonella sp serotype thompson polysaccharide.) and (ii) a response against outer membrane proteins (porins), which are present in both S . typhimurium and Salmonella sp . serotype dublin . The experiments with peripheral blood lymphocytes from Salmonella sp . serotype dublin-infected calves gave results in excellent agreement with those obtained in S . typhimurium-infected calves. J Bacteriol, 1982 Aug, 151(2), 867 - 78 Characterization of a cold-sensitive hisW mutant of Salmonella typhimurium; Davis L et al.; Previous studies of hisW mutants of Salmonella typhimurium have led to the suggestion that such strains are defective in tRNA maturation . (J . E . Brenchley and J . Ingraham, J . Bacteriol . 114:528-536, 1973) . In this study, we report that one hisW strain is defective in the accumulation of all stable RNA species . Polyacrylamide gel electrophoresis of radiolabeled RNA indicated tha at the nonpermissive temperature (20 degrees C) all stable RNa species in the cold-sensitive hisW3333 mutant were synthesized and rapidly degraded . We propose that the cold sensitivity of this strain is caused by such a restriction in stable RNA accumulation at low temperature . In vitro and in vivo studies demonstrated that the RNA degraded in this strain was synthesized de novo and was not preexisting RNA . Furthermore, physiological and genetic recovery from the cold-sensitive hisW phenotype resulted in relatively normal RNA synthesis and accumulation . Thus, the RNA alterations observed in this strain were not explained by defects in a tRNA modification enzyme . Rather, these findings suggest the existence of defective RNA processing and that a control mechanism for the overall synthesis or accumulation of stable RNA species is altered in the hisW3333 mutant. J Bacteriol, 1982 Aug, 151(2), 742 - 9 Biosynthesis of bacterial glycogen: purification and structural and immunological properties of Rhodopseudomonas sphaeroides ADPglucose synthetase; Yung SG et al.; ADPglucose synthetase from the photosynthetic bacterium Rhodopseudomonas sphaeroides was purified to greater than 95% purity . The molecular weight of the R . sphaeroides enzyme, as determined by sucrose density gradient ultracentrifugation, was approximately 204,000 . The subunit molecular weight of the enzyme based on sodium dodecyl sulfate-gel electrophoresis was 46,000 . Although the amino acid composition of the enzyme was similar to that found for the enzymes from Escherichia coli, Salmonella typhimurium, and Rhodospirillum tenue, no apparent homology has been observed between the N-terminal or C-terminal amino acid sequences . Antisera prepared against the ADPglucose synthetase could inhibit the activities of the enzyme from other photosynthetic bacteria . Therefore, some sequence homology may exist within the internal portion of their peptide chain. Biochim Biophys Acta, 1982 Jul 26, 705(2), 210 - 7 Purification and properties of the pyruvate dehydrogenase complex from Salmonella typhimurium and formation of hybrids with the enzyme complex from Escherichia coli; Seckler R et al.; The pyruvate dehydrogenase (Pyruvate:lipoamide oxidoreductase (decarboxylating and acceptor acetylating), EC 1.2.4.1) complex from Salmonella typhimurium was purified, characterized and compared to the enzyme complex from Escherichia coli . No difference could be found in the molecular weights of the native enzyme complexes or in the single polypeptide chains of the enzymes of the two organisms . Values of 100 000, 87 000 and 56 000 were obtained for the polypeptide chains of the pyruvate dehydrogenase, the dihydrolipoamide transacetylase (acetyl-CoA:dihydrolipoamide S-acetyltransferase, EC 2.3.1.12) and the dihydrolipoamide dehydrogenase (NADH:lipoamide oxidoreductase, EC 1.6.4.3) components, respectively . Complete cross-reactivity was found with antibodies directed against the pyruvate dehydrogenase complex from E . coli and electron micrographs of both enzyme complexes reveal identical structures . A high Michaelis constant for pyruvate with a Km = 6 . 10(-4) M and a somewhat weaker cooperativity as compared to the enzyme from E . coli reflect some minor differences, while the binding of the cofactor thiamine diphosphate (Km = 1 . 10(-6) M) is identical for both enzyme complexes . Reassociation to a fully active complex molecule works with equal facility between the pyruvate dehydrogenase component and a dihydrolipoamide transacetylase: dihydrolipoamide dehydrogenase subcomplex from either organism in all possible combinations. J Biol Chem, 1982 Jul 25, 257(14), 7969 - 75 Requirement of ATP in bacterial chemotaxis; Shioi JI et al.; Evidence is presented that chemotaxis requires ATP or a closely related metabolite, in addition to its known requirements of ATP for synthesis of S-adenosylmethionine (AdoMet) and maintenance of the proton motive force . Previous studies demonstrated a loss of tumbling and chemotaxis, and depletion of ATP when hisF auxotrophs of Salmonella typhimurium are starved for histidine (Galloway, R . J., and Taylor, B . L . (1980) J . Bacteriol . 144, 1068-1075) . In the present study, intracellular {AdoMet}, membrane potential, and {ATP} were measured in a hisF mutant of S . typhimurium . Membrane potential, determined from partitioning of {3H}tetraphenylphosphonium ion between the inside and the outside of the cell, was about -150 mV at pH 7.6, and did not decrease in histidine starvation but was slightly increased . The concentration of AdoMet decreased from 0.4 mM to 0.3 mM during starvation but when cycloleucine, an inhibitor of AdoMet synthetase, was used to decrease {AdoMet} by a similar amount in histidine-fed cells there was little change in tumbling frequency . Intracellular {ATP} was reduced from 4.5 mM to less than 0.2 mM by histidine starvation . About 0.2 mM ATP was necessary for spontaneous tumbling . A similar {ATP} was required for tumbling in arsenate-treated cells . Adenine at concentrations as low as 20 nM caused a transient increase in both tumbling frequency and {ATP} in histidine-starved cells . Thus, out of three parameters tested, only the intracellular {ATP} correlated with changes in tumbling frequency in the histidine-starved cells. Proc Natl Acad Sci U S A, 1982 Jul, 79(13), 4020 - 4 Genes encoding Escherichia coli aspartate transcarbamoylase: the pyrB-pyrI operon; Pauza CD et al.; In both Escherichia coli and Salmonella typhimurium there is approximately balanced synthesis of the six catalytic and six regulatory polypeptide chains of the regulatory enzyme aspartate transcarbamoylase (carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2) . This control is achieved by the contiguous pyrB and pyrI genes, which encode the catalytic and regulatory chains, respectively . Evidence for this single transcriptional unit was obtained by a study of various deletion mutations and from the DNA sequence of the intercistronic region between pyrB and pyrI . One pyrB deletion, pyrB748, produced a normal level of regulatory chains even though it removed a substantial portion of the pyrB gene . Another deletion, pyrB740, shares a similar terminus at one end within pyrB, but the promoter region is removed . In this deletion mutation, there is no production of the regulatory polypeptide, indicating that a single region adjacent to pyrB controls transcription of pyrI as well . Molecular cloning and subsequent DNA analysis demonstrated that the pyrB and pyrI genes are contiguous with pyrI as the distal gene in the operon . The cistrons are separated by a 15-nucleotide untranslated region containing a sequence capable of interacting with the 16S ribosomal RNA and allowing translation of the pyrI cistron. J Bacteriol, 1982 Jul, 151(1), 495 - 9 Identification of the Salmonella typhimurium cysB gene product by two-dimensional protein electrophoresis; Baptist EW et al.; Examination of two-dimensional electropherograms of proteins from wild-type Salmonella typhimurium and 16 different cysB strains permitted the identification of a single 34,500-dalton polypeptide chain with a pI of 7.6 that was the product of cysB . Exclusion chromatography indicated that the native cysB protein is a multimer of at least two and probably four or more such subunits. J Bacteriol, 1982 Jul, 151(1), 153 - 61 Isolation and characterization of purine regulatory mutants of Salmonella typhimurium with an episomal purE-lac fusion; Thomulka KW et al.; Expression of the purE operon of Salmonella typhimurium was analyzed by using an Escherichia coli F' episome containing a purE-lac fusion . The fusion removes the lacOP and part of the lacZ genes of the lac operon and places the intact lacY and lacA genes under control of the purE operon as shown by inhibition of growth on melibiose (lacY) and repression of thiogalactoside transacetylase (lacA) by various purines . Two classes of regulatory-deficient mutants were found among those resistant to inhibition by purines . One class was trans active (chromosomal) and corresponded to previously described purR mutants involving a deficient cytoplasmic repressor substance . These were also altered in the expression of the purF, purD, purG amd purI genes as evidenced by loss of repressibility of the synthesis of glycinamide ribotide and aminoimidazole ribotide . The other class was cis active (episomal), specific for only purE expression, and thus corresponded to an altered purE operon signal (operator or promoter) . The metabolic requirements for the expression of purE were also monitored by measuring repression of the transacetylase in strains with various genetically altered metabolic backgrounds . Repression by guanine required an intact guanine phosphorbosyltransferase (gpt) and repression by adenine and all nucleosides required purine nucleoside phosphorylase (deoD) . Synthesis of cyclic AMP (cya) and its receptor protein (crp) were no longer required for the expression of the lac genes under purE control. Cancer Res, 1982 Jul, 42(7), 2601 - 4 Mutagenicity of N-nitroso bile acid conjugates in Salmonella typhimurium and diploid human lymphoblasts; Puju S et al.; Two N-nitroso bile acid conjugates, N-nitrosotaurocholic acid and N-nitrosoglycocholic acid, were tested for mutagenicity by forward mutation assay in Salmonella typhimurium TM 677 and in diploid human lymphoblasts, line TK6 . N-Nitrosoglycocholic acid and N-nitrosotaurocholic acid showed similar concentration-response curves in the bacterial assay with statistically significant mutant fractions observed at about 0.12 mM . Nonnitrosated parent compounds were nonmutagenic . However, in the human cell assay, N-nitrosotaurocholic acid gave statistically significant mutant fractions only at 0.4 mM, but N-nitrosoglycocholic acid was mutagenic at 0.05 microM, some 9000 times more potent . Experiments with quantitative Ames' S . typhimurium reversion assays indicated mutagenesis via base substitution. Ann Immunol (Paris), 1982 Jul-Aug, 133D(1), 61 - 70 Secondary immune response to oral and nasal rough mutant strains of Salmonella typhimurium; Ivanoff B et al.; The variations in anti-Salmonella typhimurium antibody levels was measured in BALB/c mice which had been orally and nasally vaccinated with S . typhimurium live mutants of different lipopolysaccharide lengths . Together with the demonstration of immunological memory, the intensity of the secondary response was correlated with the length of the polysaccharide chain at intestinal and serum levels . Nasally administered antigen seemed to be at least as immunogenic as when orally administered. Ann Immunol (Paris), 1982 Jul-Aug, 133D(1), 103 - 17 Permeability factor-like skin reaction in rabbits induced by endotoxin of Salmonella sp; Pestana De Castro AF et al.; An inflammatory skin reaction similar to the permeability factor (PF) described for the thermolabile (TL) enterotoxin of Escherichia coli was induced in rabbits inoculated intradermally with supernatants from cultures of Salmonella typhimurium and S . enteritidis . This PF-like activity was observed with both crude supernatants as well as those which were submitted to gel filtration through Sephadex G-100 . PF-like activity was found only in fraction 1 (F1) of the chromatographed materials . It was resistant to boiling, proteolytic enzymes and wide variations of pH . Serological studies based on agglutination and immunodiffusion tests demonstrated that F1 materials were closely related to the somatic antigen of group B Salmonella . No specific TL activity, as detected by the Y-1 adrenal cell assay and the passive immune haemolysis test, could be demonstrated . Furthermore, F1 materials were not enterotoxigenic as assayed by the rabbit ileal loop assay, and no neutralization of PF-like activity could be obtained in tests carried out using F1 preparations pre-incubated with either anti-F1 or cholera antitoxin . Based upon these findings, it seems reasonable to suppose that most PF reactions, already reported as being caused by a TL-like enterotoxin produced by Salmonella, are probably due to endotoxin . In fact, this possibility was reinforced by the Sanarelli-Shwartzman phenomenon which was produced in rabbits inoculated with F1 materials. Br J Radiol, 1982 Jul, 55(655), 501 - 4 An investigation of the mutagenic potential of pulsed ultrasound; Barnett SB et al.; The possible mutagenic effect of microsecond pulses of ultrasound was investigated using 3 MHz ultrasound at diagnostic dosages, and also under conditions of increased pulse repetition frequency and acoustic power output . The first part of the study involved 5 strains of Salmonella typhimurium bacteria in which mutagenicity and viability were assessed using the Ames test, while functional competence was evaluated from microscopic observations of motility . No changes were observed in survival, in the incidence of mutants, or in microbial motility following irradiation with ultrasound intensities of 4.5 W/cm2 at temperatures ranging from 37 degrees to 43 degrees C . In the second part of this study, the frequency of sister chromatid exchange (SCE) in Chinese hamster ovary (CHO) cells, treated with similar ultrasound dosages, remained unaltered when cells were irradiated at temperatures up to 41 degrees C . At 43 degrees C and above, cell division was arrested by hyperthermia, an effect unrelated to ultrasound. Avian Dis, 1982 Jul-Sep, 26(3), 585 - 95 Reciprocal competitive exclusion of salmonella and Escherichia coli by native intestinal microflora of the chicken and turkey; Weinack OM et al.; Both the native intestinal microflora of chickens that protected chicks against salmonellae and Escherichia coli and native turkey intestinal microflora were evaluated for their reciprocal protective capacity in both species against Salmonella typhimurium and a pathogenic strain of E . coli . Nalidixic-acid-resistant forms of the S . typhimurium and E . coli strains were used in seeder-bird and individual-bird challenge tests . Reciprocal protection was provided by native chicken and turkey intestinal microflora in chicks and poults against S . typhimurium and the pathogenic strain of E . coli . The chicken and turkey microflora appeared to be equally effective in protecting the two species from S . typhimurium, but protection against E . coli was somewhat greater in the chicken than in the turkey. Zentralbl Bakteriol Mikrobiol Hyg {A}, 1982 Jul, 252(3), 340 - 6 Colony incompatibility studies among strains of Salmonella typhimurium phage type 199 isolated in connection with one outbreak; Bettelheim KA; Strains of Salmonella typhimurium phage type 199 from an outbreak of salmonellosis in the Wellington region were investigated by means of the colony incompatibility phenomenon . With the exception of one strain isolated from milk, all outbreak strains were fully compatible, despite differing in antibiotic resistance pattern and plasmid carriage . This suggests that these strains are derived from one clone . Colony incompatibility is considered a useful rapid method of epidemiological assessment of outbreaks of salmonellosis. Res Vet Sci, 1982 Jul, 33(1), 95 - 8 Establishment and persistence of Salmonella typhimurium infection stimulated by Eimeria tenella in chickens; Baba E et al.; The effect of the concurrent infections of Salmonella typhimurium and Eimeria tenella on the establishment and persistence of salmonella infection were studied in chickens using salmonella isolated from a broiler chicken . Two experiments, with three replications each, were conducted . In experiment 1, groups were composed of uninfected controls, birds infected with 40,000 E tenella oocysts, birds infected with a daily dose of 1 x 10(4) to 4 x 10(4) S typhimurium for five days after having been infected with coccidial oocysts, and birds infected with S typhimurium alone but following the same pattern as the previous group . Chickens were killed seven, 10 and 14 days after coccidial infection . In experiment 2, groups were composed of birds infected with S typhimurium and those infected with E tenella and S typhimurium in the same manner as experiment 1 but killed 17, 21, 24 and 28 days after coccidial infection . In both experiments, the number of salmonella in caecal contents and the number of chickens with salmonella in the caeca and in the liver were significantly greater in the concurrent infections than in the salmonella infection alone . No salmonella was recovered from the bile samples . Serum agglutinin was detected only from chickens infected with E tenella and S typhimurium . The results demonstrated that the establishment and persistence of S typhimurium infection were enhanced by E tenella infection in chickens. Cancer Lett, 1982 Jul-Aug, 16(2), 179 - 89 Formation of mutagens in cooked foods . V . The mutagen reducing effect of soy protein concentrates and antioxidants during frying of beef; Wang YY et al.; Cooking beef patties results in the formation of mutagens detectable by Salmonella typhimurium TA98 with metabolic activation . Decreased mutagenic activity results when frying beef with added soy protein concentrates (SPC) . The reduction in mutagenicity takes place during the cooking process . Whereas fried beef hamburgers show high mutagenic activity, by comparison, similarly fried soy-hamburgers have much less mutagenic activity . Volumetric effects are responsible partly for the reduction on mutagenicity by SPC . Naturally occurring antioxidants in SPC, such as chlorogenic acid, also play a role . Also, a commonly used antioxidant, butylated hydroxyanisole (BHA), has been found effective in reducing the mutagenicity of fried beef . Thus, the addition of SPC or BHA in beef patties may provide a practical way of reducing mutagen formation during frying of beef. Arch Microbiol, 1982 Jul, 132(1), 91 - 5 Stimulation of the anaerobic growth of Salmonella typhimurium by reduction of L-carnitine, carnitine derivatives and structure-related trimethylammonium compounds; Seim H et al.; In view of the development of a L-carnitine deficiency, the metabolism of L-carnitine and structure-related trimethylammonium compounds was studied in Salmonella typhimurium LT2 by means of thin-layer chromatography (TLC) . L-Carnitine, crotonobetaine and acetyl-L-carnitine stimulated the anaerobic growth in a complex medium significantly . The stimulation depended on the formation of gamma-butyrobetaine . The reduction of L-carnitine proceeded in two steps: (1) Dehydration of the L-carnitine to crotonobetaine, (2) hydrogenation of crotonobetaine to gamma-butyrobetaine . The reduction of crotonobetaine was responsible for the growth stimulation . Terminal electron acceptors of the anaerobic respiration such as nitrate and trimethylamine N-oxide, but not fumarate, suppressed the catabolism of L-carnitine completely . Glucose fermentation, too, inhibited the reduction of L-carnitine but optimal growth with a high carnitine catabolism was achieved by D-ribose . The esters of carnitine with medium- and long-chain fatty acids inhibited the growth considerably because of their detergent properties. Parasite Immunol, 1982 Jul, 4(4), 259 - 71 The protein-lipopolysaccharide complex extracted with trichloracetic acid from Salmonella typhimurium effective in protection of mice against S . typhimurium infection; Plant JE et al.; A protein-lipopolysaccharide complex has previously been postulated as necessary to protect susceptible mice against Salmonella typhimurium infection . Lipopolysaccharide attached to non-specific proteins, bovine serum albumin or methylated BSA, gave a specific delayed-type hypersensitivity (DTH) reaction when injected into the footpad of mice sensitized with sublethal doses of S . typhimurium . However, immunization of BALB/c mice with the complex gave no survivors after challenge with 100 LD50 S . typhimurium . Trichloracetic acid extraction of bacterial cultures produced lipopolysaccharide with attached protein . This method gave simple and convenient production of an active factor, demonstrating few major protein bands after electrophoresis . The complex elicited specific DTH reactions in sensitized mice and protected 37% of BALB/c mice against 100 LD50 S . typhimurium . Combinations of protein:lipopolysaccharide were used in DTH experiments to determine the relative importance of the components . A minimum requirement for both was demonstrated, although the ratio was not critical . Use of O-antigenic mutant strains of Salmonella indicated a role for protein in the specificity of activity of the complex. Mutat Res, 1982 Jul-Aug, 102(1), 13 - 26 Mutagenicity in Salmonella typhimurium tester strains of XAD-2-ether extract, recovered from Katsura River water in Kyoto City, and its fractions; Maruoka S et al.; The mutagenic activity of XAD-2-ether extracts recovered from Katsura River water at monthly intervals during September to December 1980 was tested on S . typhimurium TA1538, TA1535, TA98 and TA100 . The extracts showed strong mutagenic activity towards TA1538 nd TA98, especially in the presence of S9 mix . They were more active to TA1538 than to TA98 . Some of each of the XAD-2-ether extracts were pooled and separated into neutral, basic and acidic fractions, and their mutagenic activities were tested on TA1538 and TA98 to determine their contribution to the total mutagenic activity of the parent extract . The neutral fraction was responsible for most of the total mutagenic activity of the parent extract . Although the basic fraction was only 5.4% by weight of the parent extract, it was much more mutagenic than any other fraction . Its contribution to the total mutagenic activity was higher than the acidic fraction which was 30.5% by weight of the parent extract. Eur J Biochem, 1982 Jul, 125(3), 561 - 6 The primary structure of Escherichia coli K12 2-deoxyribose 5-phosphate aldolase . Nucleotide sequence of the deoC gene and the amino acid sequence of the enzyme; Valentin-Hansen P et al.; The sequence of the deoC gene of Escherichia coli K12 and the amino acid sequence of the corresponding protein, deoxyriboaldolase, has been established . The protein consists of 259 amino acids with a molecular weight of 27 737 . The purified enzyme may exist both as a monomer and as a dimer . On the basis of amino acid composition, molecular weight and catalytic properties, the enzymes from E . coli and Salmonella typhimurium seem to be almost similar . They belong to the class I aldolases, which form Schiff base intermediates . Using data for the S . typhimurium enzyme, the lysine residue involved in the active site in the E . coli enzyme was tentatively identified. Mutat Res, 1982 Jul-Aug, 102(1), 1 - 12 Mutagenic activity of 4 active-principle forms of pharmaceutical drugs . Comparative study in the Salmonella typhimurium microsome test, and the HGPRT and Na+/K+ ATPase systems in cultured mammalian cells; Dayan J et al.; The nitroimidazole derivatives used in human therapy have shown a strong mutagenic activity in bacterial tests using Ames strains of Salmonella typhimurium . Our study compared the response of 4 products of this family on bacterial target cells as well as on mammalian target cells (Chinese hamster V79 cells) . The strong positive response on TA100 was greatly reduced on the nitroreductase-deficient strain TA100 Frl . Furthermore, no mutagenic activity was found in V79 mammalian cells that we examined for ouabain and 6-thioguanine resistance. Cell, 1982 Jul, 29(3), 929 - 37 ZTP (5-amino 4-imidazole carboxamide riboside 5'-triphosphate): a proposed alarmone for 10-formyl-tetrahydrofolate deficiency; Bochner BR et al.; Starvation of Salmonella typhimurium for folate in six different ways triggers the intracellular accumulation of a novel ribotide, 5-amino 4-imidazole carboxamide riboside 5'-triphosphate (ZTP) . Numerous other starvations not involving folate do not cause ZTP to accumulate . We propose that ZTP is an alarmone for C-1-folate deficiency and present evidence that it is formed from ZMP, an intermediate in purine biosynthesis . ZMP accumulates rapidly in cells when 10-formyl-tetrahydrofolate, a substrate for ZMP transformylase, is depleted . We review previous evidence that Z-ribotides may be involved in physiological processes in many types of cells, including sporulation of Bacillus subtilis . We also discuss the implications of ZTP synthesis for chemotherapy and other pharmacological uses of antifolates and analogs of Z-ribosides. Infect Immun, 1982 Jul, 37(1), 286 - 91 P-antigen-recognizing fimbriae from human uropathogenic Escherichia coli strains; Korhonen TK et al.; P-antigen-recognizing fimbriae (P fimbriae) from four pyelonephritogenic Escherichia coli strains and type 1 fimbriae from an E . coli strain and a Salmonella typhimurium strain were purified . The P fimbriae were morphologically similar to type 1 fimbriae . The purified P fimbriae agglutinated neuraminidase-treated human P1 and P2k erythrocytes but not p erythrocytes, which lack all P-blood group-specific glycosphingolipids . However, coating of neuraminidase-treated p erythrocytes with globoside rendered such erythrocytes agglutinable by the P fimbriae . The hemagglutinations were in all instances fully inhibited by the synthetic alpha-D-Galp-(1-4)-beta-D-Galp-1-O-Me glycoside . The binding specificity of the P fimbriae could also be demonstrated by using fimbriae coated onto latex particles and nontreated erythrocytes . It was thus concluded that the P fimbriae recognize and bind to the alpha-D-Galp-(1-4)-beta-D-Galp carbohydrate sequence occurring in the series of P-blood group antigen-specific glycosphingolipids . In contrast to both type 1 fimbriae, all four P fimbriae preparations showed multiple bands in sodium dodecyl sulfate-polyacrylamide gel electrophoresis . Antisera were raised in rabbits against the various E . coli fimbriae . In enzyme-linked immunosorbent assays each one of the antisera to the P fimbriae reacted to titers of log 4 to 7 with both the homologous and the heterologous P fimbriae, but not with the type 1 fimbriae of E . coli . In a reciprocal fashion, the antiserum to the type 1 fimbriae of one E . coli strain reacted only with the homologous type 1 but not with any of the P fimbriae preparations. Food Chem Toxicol, 1982 Jun, 20(3), 259 - 63 Mutagenicity of the products obtained from heated milk systems; Rogers AM et al.; Methylene chloride extracts of the browning reaction products prepared from model systems consisting of major milk components (casein and/or lactose, and non-fat dried milk) were tested for mutagenicity in the Ames Salmonella/microsome assay . Samples obtained by heating aqueous solutions of these components under either neutral or basic (pH 10) conditions exhibited no significant mutagenic activity when tested with or without S-9 mix . The addition of common food additives, such as sodium nitrite, butylated hydroxyanisole and butylated hydroxytoluene, to the aqueous solutions did not enhance the mutagenic activity of the browning samples . On the other hand, the tar samples prepared by heating the same milk components in the dry state exhibited strong mutagenicity, primarily to Salmonella typhimurium strain TA98 and only with S-9 mix . A casein/lactose mixture and non-fat dried milk were also heated with baking soda in the dry state . The presence of the baking soda enhanced the mutagenicity of the browning products; the tar from the non-fat dried milk heated with baking soda was the most potently mutagenic of all the samples towards strain TA98 and also produced a positive response in strain TA100 in the presence of S-9 mix. Mutat Res, 1982 Jun, 94(2), 331 - 8 Influence of methionine on the mutation frequency in Salmonella typhimurium; Janion C; When reversion of some markers in S . typhimurium was tested, it was found that addition of methionine to test plates increased the revertant yields . Two assumptions were made: (1) the effect of methionine reflects the necessity of intensive synthesis of some protein(s) required for abolishing the deleterious effects and/or expressing the mutagenic effects induced by mutagens; (2) methionine influences the mutagenesis via the DNA methylation process. Infect Immun, 1982 Jun, 36(3), 1086 - 95 Outer membrane mutants of Salmonella typhimurium LT2 have lipopolysaccharide-dependent resistance to the bactericidal activity of anaerobic human neutrophils; Okamura N et al.; The capacity of neutrophil polymorphonuclear granulocytes (PMNs) to phagocytize bacteria under anaerobic as well as aerobic conditions afforded the opportunity to compare the bactericidal activities of oxygen-independent and oxygen-dependent antimicrobial mechanisms in human PMNs challenged with Salmonella typhimurium LT2 and its lipopolysaccharide mutants (outer membrane mutants) . Anaerobic human PMNs challenged with either opsonized LT2 or serum-treated zymosan failed to produce detectable superoxide anion (O2-) or to reduce nitroblue tetrazolium, although aerobic PMNs readily produced O2- in response to such challenge . Anaerobic PMNs killed these bacteria in an ordered fashion that appeared to be dependent on their lipopolysaccharide chemotype . As the carbohydrate content of the mutant lipopolysaccharide decreased, the bacteria became less resistant to the oxygen-independent bactericidal activity . The results resembled the ordered resistance to oxygen-independent killing observed with LT2 and its mutants in PMN-free systems with PMN granule proteins . Studies on the kinetics of killing showed these to be less rapid in anaerobic as compared with aerobic conditions . Opsonization increased the rate of phagocytosis, but such factors as opsonization and the rate of phagocytosis did not appear to affect intraleukocytic bactericidal capacity in that the resultant proportion of bacteria remaining viable after ingestion was similar regardless of which serum was used (normal serum, C6-deficient serum, C8-deficient serum, or no serum at all) . The results are consistent with an active and substantial participation by oxygen-independent systems in the antimicrobial effects of neutrophils. J Hyg (Lond), 1982 Jun, 88(3), 557 - 65 The survival of multi-antibacterial drug-resistant Escherichia coli and Salmonella typhimurium in stored static slurry from a veal calf unit; Hinton M et al.; Salmonella typhimurium phage type DT 193 survived in small numbers, in stored static slurry derived from veal calves, for the 7-week period of observation . The viable coliform count fell by 1 1/2 logs during the first 2 weeks of storage, thereafter there were only relatively small fluctuations in the coliform population . In all 735 of 752 Escherichia coli isolates examined from eight samples of slurry were resistant to 3-6 antibacterial drugs . There was no dramatic change in the overall level of drug resistance amongst the E . coli with time . Chloramphenicol resistance was recorded in 400 (55%) of the E . coli . It was always associated with multiple resistance, with 96% of the strains being resistant to 5 or 6 drugs, although the proportion of isolates of each of the ten most prevalent O-serotypes resistant to chloramphenicol was variable and ranged between none and 97.5% . The use of biotyping together with O-serotyping indicated that the E . coli population was extremely complex, although certain components of the population remained relatively stable within the dominant flora with time since several of the more common O-serotype/biotype combinations were isolated from more than half of the eight slurry samples examined. Anesthesiology, 1982 Jun, 56(6), 462 - 3 Mutagenicity of experimental inhalational anesthetic agents: sevoflurane, synthane, dioxychlorane, and dioxyflurane; Baden JM et al.; A modification of the Ames bacterial assay system employing two histidine-dependent strains of Salmonella typhimurium, TA1535 and TA100, was used to test the mutagenicity of four experimental, inhalational anesthetic agents: sevoflurane, synthane, dioxychlorane, and dioxyflurane . None of the anesthetics was mutagenic . Increased activity was seen only with vinylidene chloride, the positive control. Mutat Res, 1982 Jun, 101(4), 293 - 304 Mutagenicity study of fried sausages in Salmonella, Drosophila and mammalian cells in vitro and in vivo; Gocke E et al.; The basic extract of pan-fried sausages was studied for mutagenic potential in seven test systems . Mutagenic activity was high in the standard Ames assay in the Salmonella typhimurium strains TA1538 and TA98 in presence of S9 mix . In vivo, in the intrasanguine host-mediated assay with strain TA98 on Aroclor-pretreated mice, the mutagenic activity of the extract was low . A borderline activity was seen in the SCE assay in vitro with V79 Chinese hamster cells in presence of S9 mix . No significant mutagenic action was found in the gene-mutation assay for thioguanine resistance with V79 cells, the Drosophila sex-linked recessive lethal test, the micronucleus test and the mammalian spot test. Pathol Biol (Paris), 1982 Jun, 30(6 Pt 2), 484 - 7 {Activity of amoxicillin and ampicillin against infection with Salmonella typhimurium in mice }; Avril JL et al.; Experimental mouse intraperitoneal or intragastric infection due to Salmonella typhimurium C5 was treated with subcutaneous amoxicillin or ampicillin . The minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC) of the two penicillins were similar . Amoxicillin was significantly more effective than ampicillin in protecting the animals from the lethal effects of the infection . The enumeration of bacteria from spleen and Peyer's patches of the small intestine showed that amoxicillin killed S . typhimurium faster than ampicillin. J Pharmacobiodyn, 1982 Jun, 5(6), 423 - 9 Oxygen--insensitive nitrofuran reductases in Salmonella typhimurium TA100; Tatsumi K et al.; The present study demonstrated by DEAE-cellulose column chromatography that oxygen-insensitive nitrofuran reductases in Salmonella typhimurium TA100 consisted of at least two reductases, NADPH- and NAD(P)H-linked enzymes . The NADPH- and NADH-linked activities of the latter enzyme seemed to originate from a single enzyme, because both activities were similarly inactivated by heat and urea treatments, and also inhibited by dicumarol . On the other hand, the NADPH-linked enzyme was less sensitive to heat, urea and dicumarol . Furthermore, the study showed that the NAD(P)H-linked enzyme was a flavoenzyme which could be inactivated by dialysis against 1 M potassium bromide and reactivated by FMN. Cell Biophys, 1982 Jun-Sep, 4(2-3), 163 - 75 Anionic sites on the envelope of Salmonella typhimurium mapped with cationized ferritin; Magnusson KE et al.; Binding of either ferritin (F) or cationized ferritin (CF) was employed to indicate the surface charge of the envelope of mainly two Salmonella typhimurium strains (395 MR10, a Rd-mutant, and LT2-M1, a UDP-galactose-4-epimerase-less mutant) . Lowering the pH from 7 to 4 decreased binding of CF, but increased binding of F . At low concentrations, the distribution of CF on S . typhimurium 395 MR10 was in general random, with individual ferritin molecules often forming clusters of two or three particles . At ionic strengths of 0.25M NaCl, ferritin produced distinctive, larger clusters at relatively few sites (10-50/cell) . Addition of galactose to cultures of growing S . typhimurium, LT2-M1 reduced the binding of CF in 1-10 min, and numerous ferritin-free areas became visible . Possibly this is caused by a pluri-focal reduction in the negative cell surface charge that was generated at the multiple sites of export of new, smooth-type lipopolysaccharide, which either exhibits lesser charge or masks a preexisting surface charge . Dividing cells may show unequal charges on the prospective daughter cells, and the difference in the capacity for ferritin adsorption of both daughter cells is sharply separated at the division site. Infect Immun, 1982 Jun, 36(3), 1168 - 74 Association of type 1 pili with the ability of livers to clear Salmonella typhimurium; Leunk RD et al.; The role of type 1 pili in the adherence of Salmonella typhimurium strain SR-11 to hepatic sinusoidal cells was investigated . An average of 66.7% of piliated organisms was cleared by perfused livers on a single pass . Mannose and alpha-methyl-D-mannoside inhibited such trapping in a dose-dependent manner . Preincubation of the bacteria, but not the liver, with either sugar also inhibited trapping, suggesting that the sugar binds to bacterial, not hepatic, receptors . Significant numbers of previously trapped bacteria could be eluted by adding mannose to the wash medium . Bacteria with reduced piliation, obtained either by growing bacteria on agar or by using a nonpiliated variant of the parent strain, were trapped to a significantly lesser extent than the parent strain . The liver appears to selectively trap heavily piliated organisms since reperfusion of bacteria through a second liver results in significantly less trapping than occurs with the first perfusion . In vivo, the nonpiliated variant strain was cleared much more slowly than the piliated parent strain . Mannose and alpha-methyl-D-mannoside, but not glucose, decreased clearance rates of piliated organisms . Cumulatively, the data suggest that type 1 pili are a major factor in hepatic clearance of S . typhimurium. J Biol Chem, 1982 May 25, 257(10), 5772 - 8 Bacteriophage SP6-specific RNA polymerase . I . Isolation and characterization of the enzyme; Butler ET et al.; SP6 is a small, virulent bacteriophage which grows on Salmonella typhimurium LT2 . It is morphologically similar to Escherichia coli bacteriophage T7 and its relatives, but appears to be genetically distinct . After infection a bacteriophage-specific RNA polymerase is induced in infected cells . SP6 RNA polymerase is a stable enzyme and is easily purified to homogeneity in good overall yield . The activity resides in a single polypeptide chain of Mr = 96,000 . Synthesis of RNA by SP6 RNA polymerase requires a DNA template and Mg2+ ion and is strongly stimulated by either bovine serum albumin of spermidine . Thiol-reactive reagents inhibit the enzyme, suggesting the presence of essential sulfhydryl residues . RNA synthesis requires native SP6 RNA as template; DNAs from other bacteriophages including T3 and T7 are inert; hence, SP6 RNA polymerase possesses a stringent promoter specificity similar to, but distinct from that of the other phage RNA polymerases . The SP6 RNA polymerase is also highly active in synthesis of poly(rG) with poly(dI) . (dC) as template . This reaction is unlikely to involve promoter-like sites, but it appears to reflect a general catalytic capacity of the polymerase, since cleavage of the SP6 RNA polymerase with trypsin, which completely eliminates SP6-transcribing activity, has little effect on poly(rG) synthesis . Hence, it appears that the catalytic portion of the polymerase can be separated from the RNA polymerase holoenzyme. J Biol Chem, 1982 May 25, 257(10), 5779 - 88 Bacteriophage SP6-specific RNA polymerase . II . Mapping of SP6 DNA and selective in vitro transcription; Kassavetis GA et al.; DNA from bacteriophage SP6 grown on Salmonella typhimurium LT2 is a linear duplex with a unique DNA sequence having a molecular weight of 2.9 x 10(6) (43.500 base pairs) . Restriction endonuclease cleavage maps on SP6 DNA for Ava II, Kpn I, Bgl II, Eco RI, and HindIII have been determined . SP6 DNA is transcribed selectively in vitro by Escherichia coli RNA polymerase, predominantly from three strong promoter sites located near the left end of the standard physical map, reading rightward to a termination site near 6,000 base pairs . Transcription in vitro by purified SP6-specific RNA polymerase gives rise to at least 10 discrete RNA species, all of which are read rightward . Promoter sites for these species are located throughout the rightmost 90% of the SP6 DNA molecule, although precise mapping has not yet been carried out . The general form of the SP6 transcriptional map is similar to the T7- and T3-like phages, although no gross sequence homologies are evident from DNA-RNA hybridization experiments. Toxicol Lett, 1982 May, 11(3-4), 313 - 20 Mutagenicity of three aromatic amines in the presence of fractions from various tissues; Fouarge M et al.; The mutagenic activity of 2-aminofluorene, 4-aminobiphenyl and 3,2'-dimethylaminobiphenyl towards Salmonella typhimurium strain TA1538 was tested in the presence of post-mitochondrial fractions of liver, kidney, intestine, colon and testicle from untreated and pretreated rats . The metabolic activation capacity of these various fractions was very different . In the experimental conditions, no relationship was found between the mutagenic activity and the carcinogenicity of the three aromatic amines. Toxicol Lett, 1982 May, 11(3-4), 305 - 11 Role of glutathione in liver-mediated mutagenicity of acrylonitrile; Duverger-Van Bogaert M et al.; The mutagenic activity of acrylonitrile (ACN) towards the Salmonella typhimurium strain TA1530 was evaluated after a short preincubation time in liquid medium in the presence of microsomes, cytosolic fractions and post-mitochondrial fractions of liver from untreated and phenobarbitone (PB)-pretreated rats and mice . The effect of the presence of glutathione (GSH) was also examined . GSH enhanced the microsomal-mediated mutagenicity of ACN; that effect was abolished in the presence of CO . The effect of GSH was usually greater after pretreatment by phenobarbitone . Other sulfhydryl compounds induce a weaker mutagenic activity than GSH . These observations support the hypothesis of a mediated formation of a mutagen involving GSH, but the adduct between ACN an GSH was not mutagenic. Mutat Res, 1982 May, 94(1), 13 - 21 Biologically active aromatic amines derived from carcinogenic polycyclic aromatic hydrocarbons: synthesis and mutagenicity of aminobenzo{a}pyrenes; Fu PP et al.; The mutagenicities of 6-aminobenzo{a}pyrene (6-NH2-BP), 4-, 11- and 12-NH2-BP, and two N,N-diacetyl derivatives (4- and 12-N(Ac)2-BP) were compared to that of the present compound, BP, and to the aromatic amine, 2-aminofluorene (AF), in the Ames' Salmonella typhimurium assay . In the presence of an S9 activating system all the compounds were mutagenic in strains TA100, TA98 and TA1538 was 4-NH2-BP greater than 4-N(Ac)2-BP greater than 12-NH2-BP greater than 12-N(Ac)2-BP greater than AF greater than 11-NH2-BP congruent to BP greater than 6-NH2-BP; whereas in strain TA100, the order was 4-NH2-BP greater than 4-N(Ac)2-BP greater than BP greater than 12-NH2-BP congruent to 12-N(Ac)2-BP congruent to 11-NH2-BP greater than 6-NH2-BP congruent to AF . Inclusion of the deacylase inhibitor, paraoxon, in the incubation decreased the mutagenicity of 4-N(Ac)2-BP but had no effect on its primary amine . These data suggest that, at least for this group of compounds, arylamines derived from carcinogenic polycyclic aromatic hydrocarbons are activated to potent mutagens primarily through S9-mediated metabolism (e.g., N-oxidation) of the amine. Am J Vet Res, 1982 May, 43(5), 916 - 8 Leukocyte migration inhibition in chickens inoculated with Salmonella typhimurium; Nagaraja KV et al.; Leukocyte migration-inhibition tests were conducted in chickens infected with Salmonella typhimurium . A relatively new and simple method that involves the migration of leukocytes under agarose gel was used . Migration distance was projected onto a white background at 40X magnification, using a microprojector . Quantitation of migration was done by measuring the linear distance the cells had moved from the margin of the agarose wells . The details of the technique and the importance of it in studies of cell-mediated immune response are discussed . Chickens inoculated with S typhimurium had a significant leukocyte migration inhibition. Proc Natl Acad Sci U S A, 1982 May, 79(9), 2855 - 9 Mutagenicity of oxygen free radicals; Moody CS et al.; Paraquat (1,1'-dimethyl-4,4'-bipyridinium dichloride) was used as an intracellular generator of oxygen free radicals and was found to be highly mutagenic for Salmonella typhimurium . It caused both base-pair substitution and frameshift mutations . Paraquat was much more toxic and mutagenic in a simple nutritionally restricted medium than in a rich complex medium . The mutagenicity of paraquat was dependent upon the presence of a supply of both electrons and oxygen . Cells containing high levels of superoxide dismutase (superoxide:superoxide oxidoreductase, EC 1.15.1.1) were more resistant to the toxicity and the mutagenicity of paraquat than were cells containing normal levels of this enzyme . The mutagenicity of paraquat thus appears to be due to its ability to exacerbate the intracellular production of superoxide radicals. Mutat Res, 1982 May, 101(3), 175 - 87 Mutagenicity of pyrolysates from guanidine, ureide, secondary amines and polyamines found by the Salmonella/mammalian-microsome test; Ohe T; Nitrogenous compounds such as guanidine, ureide, secondary amines and polyamines were pyrolysed at 300, 400, 500 and 600 degrees C for 3 min, and the mutagenic activities of the pyrolysates were assayed on Salmonella typhimurium TA98 and TA100 with or without metabolic activation by S9 mix . Among 21 pyrolysates tested, 14, from methylguanidine, agmatine, dihydrouracil, dimethylamine, diethylamine, trimethylamine, triethylamine, pyrrolidine, morpholine, sarcosine, piperazine, piperidine, spermine and spermidine, showed mutagenic activity . In the presence of S9 mix, the mutagenic activity began to appear from the pyrolysate at 400 degrees C, and the pyrolysate at 600 degrees C showed the highest mutagenic activity except that from methylguanidine . The mutagenic activity formed by pyrolysis was more active on TA98 than TA100 . In the absence of S9 mix, only 3 pyrolysates - from dimethylamine, diethylamine and pyrrolidine - showed slight mutagenic activity toward TA100 . The highest mutagenic activity was observed with the pyrolysate from spermine, followed by those from piperidine, spermidine, piperazine and triethylamine . Some nitrogenous compounds showed slight mutagenic activity after pyrolysis at 300 degrees C for 20 min, although none of the compounds tested showed any mutagenic activity after pyrolysis at 300 degrees C for 3 min. J Med Chem, 1982 May, 25(5), 593 - 5 Effect of 4'-halogen substitution on the mutagenicity of trans-4-acetamidostilbene and trans-4-(N-hydroxyacetamido)stilbene in the Salmonella typhimurium test system; Shirota FN et al.; The effect of halogen substituents placed at the 4' position of trans-4-acetamidostilbene (1, AAS) to alter the pattern of biotransformation and thus the mutagenicity of these derivative was evaluated by comparing the mutagenic effects of 1 on Salmonella typhimurium TA-100 with the corresponding 4'-F (2), 4'-Cl (3), and 4'-Br (4) analogues . The mutagenic properties of trans-4-(N-hydroxyacetamido)stilbene (5) and its 4'-F (6), 4'-Cl (7), and 4'-Br (8) derivatives were also evaluated in this system . Both the amides (1-4) and hydroxamic acids (5-8) required the presence of a metabolic activating system prepared from hamster liver in order to produce a mutagenic effect . All of these compounds were mutagenic to A-100 . Their mutagenic potencies were markedly influenced by the 4'-halogen substituents, the relative mutagenic potencies of the amides being 2 (4'-F) greater than 1 (4'-H), 3 (4'Cl) greater than 4 (4'-Br), while the hydroxamic acids followed the order of 1 (4'-H) greater than 2 (4'-F) greater than 3 (4'-Cl), 4 (4'-Br). Infect Immun, 1982 May, 36(2), 710 - 3 Transovarian passage, visceral distribution, and pathogenicity of salmonella in snakes; Chiodini RJ; Transovarian passage of salmonella was evaluated in snakes by cesarean delivery and subsequent bacteriological examination of fetuses . In all cases, the same Salmonella serotype was isolated from the feces of gravid females and their fetuses . The visceral distribution of salmonella in normal snakes was found to involve almost all visceral organs . Of nonenteric organs examined, salmonella was recovered most often from the livers and ureters . Experimental infections with Salmonella typhimurium and Salmonella arizonae were established by oral, intracardial, and intracoelomic routes . Animals infected orally shed the organism in feces, but did not develop humoral antibodies or any detectable adverse effect . Animals injected by the intracardiac and intracoelomic routes developed antibody titers of 1:256 to the respective salmonella serotypes, but remained normal throughout the experiment . On the basis of results, salmonella was regarded as an opportunistic organism in reptiles. J Bacteriol, 1982 May, 150(2), 456 - 64 Relationship between cell death and altered lipid A synthesis in a temperature-sensitive lethal mutant of Salmonella typhimurium that is conditionally defective in 3-deoxy-D-manno-octulosonate-8-phosphate synthesis; Rick PD et al.; The relationship between the inability to synthesize a complete 3-deoxy-D-manno-octulosonate region of lipopolysaccharide and cell death was investigated in a temperature-sensitive lethal mutant of Salmonella typhimurium . The defect in lipopolysaccharide synthesis is due to a mutation in the structural gene for 3-deoxy-D-manno-octulosonate-8-phosphate synthetase (designated kdsA) and results in the synthesis of a temperature-sensitive enzyme . Expression of the kdsA lesion at elevated temperatures, at which the synthesis of 3-deoxy-D-manno-octulosonate is complete blocked, is required for expression of the temperature-sensitive lethal phenotype . However, the defect in lipopolysaccharide synthesis is not alone sufficient cause for the observed cell death . Genetic evidence if presented which indicates that the mutant possesses a second mutation, or possibly multiple mutations, whose lethal expression is dependent on the inability of the mutant to synthesize a fully acylated and 3-deoxy-D-manno-octulosonate-substituted lipid A portion of lipopolysaccharide at elevated temperatures. J Bacteriol, 1982 May, 150(2), 447 - 55 Isolation and characterization of a temperature-sensitive lethal mutant of Salmonella typhimurium that is conditionally defective in 3-deoxy-D-manno-octulosonate-8-phosphate synthesis; Rick PD et al.; A new mutant of Salmonella typhimurium was isolated which possesses a temperature-sensitive defect in the synthesis of 3-deoxy-D-manno-octulosonic acid . The defect in 3-deoxy-D-manno-octulosonic acid synthesis is due to a temperature-sensitive 3-deoxy-D-manno-octulosonate-8-phosphate synthetase, and the mutant accumulates an incomplete lipid A under nonpermissive conditions . Evidence is presented which indicates that the incomplete lipid A molecule is most likely identical in structure to the lipid A precursor synthesized by previously characterized mutants conditionally defective in 3-deoxy-D-manno-octulosonic acid synthesis . However, unlike related mutants which undergo growth stasis under nonpermissive conditions, the accumulation of lipid A precursor in the new mutant results in cell death at elevated temperatures. Gene, 1982 May, 18(2), 157 - 63 The nucleotide sequence of the araC regulatory gene in Salmonella typhimurium LT2; Clarke P et al.; The nucleotide sequence of the araC regulatory gene of Salmonella typhimurium LT2 has been determined . This sequence and the predicted araC translational product are compared to their counterparts in Escherichia coli . The two genes code for similar products although the S . typhimurium protein is eleven amino acids shorter than the E . coli protein . The predicted amino acid sequences are 92% conserved and the DNA sequences are 82% conserved for the common regions of the two genes. Mutat Res, 1982 May-Jun, 104(4-5), 209 - 13 Mutagenicity of some methylated benzo{a}pyrene derivatives; Santella R et al.; The mutagenicity of benzo{a}pyrene (BP) and a number of methylated derivatives towards Salmonella typhimurium has been tested . The most mutagenic derivative tested was 6-methylbenzo{a}pyrene which produced about twice the number of revertants as did BP, 11-Methylbenzo{a}pyrene was slightly more mutagenic than BP . All the other compounds tested (7-, 8-, 9- and 10-methylbenzo{a}pyrene and 7,8- and 7,10-dimethylbenzo{a}pyrene) were significantly less active than benzo{a}pyrene . With the exception of 6-methylbenzo{a}pyrene, these results closely parallel the known carcinogenicity of the methylated benzo{a}pyrenes, and support the view that metabolic activation of BP may involve the 7-10 positions which are blocked in the methylated compounds. J Bacteriol, 1982 May, 150(2), 795 - 803 Genetic characterization of the glutamate dehydrogenase gene (gdhA) of Salmonella typhimurium; Rosenfeld SA et al.; Salmonella typhimurium mutants, either devoid or glutamate dehydrogenase activity or having a thermolabile glutamate dehydrogenase protein, were used to identify the structural gene (gdhA) for this enzyme . Transductions showed that the mutations producing these phenotypes were linked to both the pncA and nit genes, placing the gdhA locus between 23 and 30 U on the S . typhimurium chromosome . Additional transductions with several Tn10 insertions established the gene order as pncA-gdhA-nit . Since few genetic markers exist in this region of the chromosome, Hfr strains were constructed to orient the pncA-gdhA-nit cluster with outside genes . Conjugation experiments provided evidence for the gene order pyrD-pncA-gdhA-nit-trp . To further characterize gdhA, we used Mu cts d1 (Apr lac) insertions in this gene to select numerous strains containing deletions with various endpoints . Transductions of these deletions with strains containing different gdh mutations and with a mutant having a thermolabile glutamate dehydrogenase protein permitted us to construct a deletion map of the gdhA region. J Bacteriol, 1982 May, 150(2), 604 - 15 Phosphoenolpyruvate:sugar phosphotransferase system-mediated regulation of carbohydrate metabolism in Salmonella typhimurium; Nelson SO et al.; The crr mutation was shown to affect the phosphoenolpyruvate:sugar phosphotransferase system-mediated transient repression of the lac operon, intracellular cAMP levels, and sensitivity to inducer exclusion . Our results indicate that the presumed crr gene product, factor IIIGlc, plays a direct role in the regulation of inducer exclusion . We propose a mechanism in which inducer exclusion depends on both the level and state of phosphorylation of factor IIIGlc and the level of an inducer exclusion-sensitive transport system . The results of studies on the sensitivity to inducer exclusion of glycerol and maltose in cultures induced for short periods of time on these substrates (resulting in varying degrees of activity of the respective transport systems) support this model of inducer exclusion . Previously, the crp*-771 mutation has been shown to result in an altered cAMP receptor protein, which has a changed affinity for cAMP, and to affect the sensitivity for inducer exclusion of glycerol . Changes in other functions of the altered cAMP receptor protein were indicated by our results; these changes were in the roles of this protein in (i) the cAMP-dependent initiation of transcription of the lac operon and (ii) the regulation of intracellular cAMP levels and the export of cAMP . We propose that the crp*-771 mutation has an indirect effect in relieving inducer exclusion in repressed or hypersensitive strains, in which the crp*-771 mutation allows the synthesis of inducer exclusion-sensitive transport systems to higher levels than the levels found in strains containing wild-type cAMP receptor protein. Cancer Res, 1982 May, 42(5), 1620 - 3 Selective activation of some dihydrodiols of several polycyclic aromatic hydrocarbons to mutagenic products by prostaglandin synthetase; Guthrie J et al.; The ability of prostaglandin synthetase (PGS) to cooxidize benzo(a)pyrene, benzo(a)anthracene, chrysene, and several of their dihydrodiol derivatives to mutagenic products was tested with Salmonella typhimurium strains TA98 and TA100 . The microsomal fraction of ram seminal vesicles, a known source of PGS, in the presence of the PGS substrate arachidonic acid, metabolized benzo(a)pyrene-7,8-dihydrodiol, benzo(a)anthracene-3,4-dihydrodiol, and chrysene-1,2-dihydrodiol to mutagenic products . This activity was inhibited by the PGS inhibitor indomethacin . Unlike the PGS system, however, a cytochrome P-450-reduced nicotinamide adenine dinucleotide phosphate-dependent system, present in an Aroclor 1254-induced rat liver 9000 x g supernatant fraction, also activated the parent compounds {benzo(a)pyrene, benzo(a)anthracene, chrysene} and several other benzo(a)anthracene dihydrodiols (the 1,2-dihydrodiol, the 8,9-dihydrodiol, and the 10,11-dihydrodiol) . The chrysene trans-3,4, trans-5,6, and cis-5,6 diols were not activated to mutagens by either system . Thus, the PGS system appears to be more selective than does the cytochrome P-450 system in the activation of polycyclic aromatic hydrocarbons to mutagenic products, activating only those dihydrodiols with adjacent double bonds in the bay region from which the bay-region diol-epoxides are formed. Parazitologiia, 1982 May-Jun, 16(3), 238 - 41 {Immune reactions of Ornithodoros papillipes ticks (Argasidae) to the administration of different microorganisms}; Podboronov VM et al.; It has been shown that ticks possess cellular factors of organism protection which fulfil functions of seizure and digestion of different microorganisms in a way similar to phagocytosis . In response to the introduction of bacteria lysozyme quantity increases in tick's haemolymph that exerts a bactericide effect on the introduced strains Micrococcus lysodeikticus 2665, Staphilococcus aureus 209 and Salmonella typhimurium IT-2 . When administering phage FX-174 into tick's haemolymph a persistence of phage particles during 1-2 months is observed . Specific antibodies developing in response to introduced phage corpuscles were not found. Antonie Van Leeuwenhoek, 1982 May, 48(2), 159 - 67 Expression of recA-gene dependent SOS functions in Salmonella typhimurium; Guerrero R et al.; Thymine starvation of RecA+ Thy- strains of Salmonella typhimurium does not induce the inhibition of cellular respiration, one of the recA-gene dependent SOS functions . Nevertheless, thymine deprivation is able to produce a normal induction of prophage and thymineless death in these same strains However, when these mutants are treated, in the presence of thymine, with UV-irradiation or bleomycin, they show a normal inhibition of cellular respiration and other SOS functions . Thus, one injurious treatment (thymine deprivation) may trigger prophage induction but not cessation of respiration, whereas another agent (UV-irradiation) may induce both . Together, these results suggest a possible discrimination in the pathways and conditions of expression of various SOS functions. Food Chem Toxicol, 1982 Apr, 20(2), 209 - 12 Lack of mutagens in deep-fat-fried foods obtained at the retail level; Taylor SL et al.; The basic methylene chloride extract from 20 of 30 samples of foods fried in deep fat failed to elicit any mutagenic response that could be detected in the Salmonella typhimurium/mammalian microsome assay . The basic extracts of the remaining ten samples (all three chicken samples studied, two of the four potato-chip samples, one of four corn-chip samples, the sample of onion rings, two of six doughnuts, and one of three samples of french-fried potato) showed evidence of weak mutagenic activity . In these samples, amounts of the basic extract equivalent to 28.5-57 g of the original food sample were required to produce revertants at levels of 2.6-4.8 times the background level . Only two of the acidic methylene chloride extracts from the 30 samples exhibited mutagenic activity greater than 2.5 times the background reversion level, and in both cases (one corn-chip and one shrimp sample) the mutagenic response was quite weak . The basic extract of hamburgers fried in deep fat in a home-style fryer possessed higher levels of mutagenic activity (13 times the background reversion level) . However, the mutagenic activity of deep-fried hamburgers is some four times lower than that of pan-fried hamburgers. Cancer Res, 1982 Apr, 42(4), 1446 - 53 Mutagenic and alkylating activities of 3-methyl-1-phenyltriazenes and their possible role as carcinogenic metabolites of the parent dimethyl compounds; Malaveille C et al.; 3-Methyl-1-phenyltriazene and a series of ring-substituted derivatives (4-methylphenyl, 4-chlorophenyl, and 2,4,6-trichlorophenyl), structurally related benzenediazonium fluoborates and phenyl azides, as well as the recently isolated {1-methyl-3-(2,4,6-trichlorophenyl)-2-triazeno}methyl-beta-D-glucopyranoside uronic acid, were studied for their mutagenic activity in Salmonella typhimurium strains . Of these compounds, the 3-methyl-1-phenyltriazene derivatives and 2,4,6-trichlorobenzenediazonium fluoborate were found to be direct-acting mutagens; the glucuronide was active in strain TA 1530 only after deconjugation with beta-glucuronidase . The half-lives of the monomethylphenyltriazenes in vitro were determined and compared with their methylating activity towards 4-(4-nitrobenzyl)pyridine and their mutagenicity . The results are discussed in relation to the possible mechanism of action of the N,N-dimethylphenyltriazenes and their monomethyl derivatives as mutagens and organ-specific carcinogens. Cancer Res, 1982 Apr, 42(4), 1243 - 8 Identification of mutagenic metabolites formed by C-hydroxylation and nitroreduction of 5-nitroacenaphthene in rat liver; EL-Bayoumy K et al.; The metabolism of the mutagen and carcinogen, 5-nitroacenaphthene, by the 9000 x g supernatant from the livers of Aroclor-pretreated rats was studied . The major primary metabolites were 1-hydroxy-5-nitroacenaphthene and 2-hydroxy-5-nitroacenaphthene . These metabolites were oxidized to 1-oxo-5-nitroacenaphthene and 2-oxo-5-nitroacenaphthene, hydroxylated to cis-1,2-dihydroxy-5-nitroacenaphthene and trans-1,2-dihydroxy-5-nitroacenaphthene, and reduced to 1-hydroxy-5-aminoacenaphthene and 2-hydroxy-5-aminoacenaphthene . Reduction of 1- and 2-oxo-5-nitroacenaphthene to 1-oxo- and 2-oxo-5-aminoacenaphthene was also observed . When incubations were carried out in a N2-enriched atmosphere (10% O2 in N2), the major metabolites were 1-hydroxy- and 2-hydroxy-5-nitroacenaphthene and 2-oxo-5-aminoacenaphthene . Selected metabolites were tested for mutagenicity toward Salmonella typhimurium TA 98 . The most mutagenic of the metabolites tested, in the presence or absence of rat liver 9000 x g supernatant, were 1-hydroxy-5-nitroacenaphthene and 1-oxo-5-nitroacenaphthene . These results indicate that the 9000 x g supernatant from the livers of Aroclor-pretreated rats is capable of catalyzing both the oxidation and reduction of 5-nitroacenaphthene and that the reduced derivatives of 1-hydroxy- or 2-hydroxy- or 1-oxo- or 2-oxo-5-nitroacenaphthene are proximate mutagens. Mutat Res, 1982 Apr, 101(2), 99 - 114 Screening of antioxidants and other compounds for antimutagenic properties towards benzo{a}pyrene-induced mutagenicity in strain TA98 of Salmonella typhimurium; Calle LM et al.; Antioxidants and several other compounds, some of which are known to inhibit carcinogenicity, have been screened for their effectiveness as inhibitors of benzo{a}pyrene (BP) mutagenicity towards Salmonella typhimurium strain TA98 in the Ames test . A total of 32 compounds were tested . In the assay, metabolic activation of BP (8.2 nmoles/plate) was mediated by the S9 fraction from beta-naphthoflavone-induced rat livers . Among compounds which are known to inhibit carcinogenicity, retinol, phenothiazine, disulfiram, phenethylisothiocyanate and phenylisothiocyanate were the most effective inhibitors of BP mutagenicity, being effective at equimolar concentrations . Several other compounds showed inhibition at higher concentrations of antioxidant and the remainder showed little or no inhibition . Dose-response curves have been obtained for the 17 most active compounds . No general pattern of inhibition is obvious from our studies, inhibitors are not drawn ;from any single class of compounds, nor does a particular compound necessarily appear to inhibit more than one mutagen. Mutat Res, 1982 Apr, 101(2), 141 - 50 Mutagenicity of substituted carbazoles in Salmonella typhimurium; LaVoie EJ et al.; Mutagenic activities of 1-, 2-, 3-, 4-, and 9-methylcarbazole were evaluated in S . typhimurium TA1535, TA1537, TA1538, TA98, and TA100 . Only 9-methylcarbazole was found to be mutagenic in S . typhimurium TA100 in the presence of rat-liver homogenate . Mutagenic activity was also observed in TA100 for 2,9-, 3,9-, and 4,9-dimethylcarbazole . None of these methylated carbazole derivatives was mutagenic in TA1535, TA1537, TA1538 and TA98 in either the presence of absence of rat-liver homogenate . These results indicate that a 9-methyl substituent is associated with the mutagenic activity of these carbazole derivatives . Comparative studies on the mutagenic activity of 9-substituted carbazoles demonstrated that the activity of 9-ethylcarbazole was less than that of 9-methylcarbazole . 9-Phenyl- and 9-i-propylcarbazole were inactive under identical assay conditions . 9-Hydroxymethylcarbazole, a major metabolite of 9-methylcarbazole, was confirmed to be a direct-acting mutagen in S . typhimurium TA100 . 9-Formylcarbazole was inactive as a mutagen when assayed with or without metabolic activation . These data are consistent with the finding that 9-hydroxymethylcarbazole is a major proximate mutagenic form of 9-methylcarbazole. Biochimie, 1982 Apr, 64(4), 239 - 46 An immunoradiometric quantitative assay of Escherichia coli recA protein; Paoletti C et al.; A two-site immunoradiometric assay of Escherichia coli recA protein is described ; its sensitivity allows the detection of 0.1 ng of recA protein ; it yields a linear response for amounts of recA protein in the 0.1-7 ng range . It can be directly applied to extracts of Escherichia coli obtained by sonication . Salmonella typhimurium extracts contain some cross-reacting material which share common antigenic determinants with Escherichia coli recA protein but differ from it. Toxicol Lett, 1982 Apr, 11(1-2), 95 - 101 Metabolic activation of dimethylnitrosamine to mutagens: role of cytochromes P-450 and P-448; Phillipson CE et al.; Pretreatment of hamsters with phenobarbitone, 3-methylcholanthrene and Arochlor 1254 induced the hepatic microsomal mixed function oxidases, yet decrease the efficiency of activation of dimethylnitrosamine (DMN) to intermediates mutagenic to the Salmonella typhimurium strain TA-100 . Furthermore, no correlation was obtained between cytochrome P-450 content, microsomal demethylation of DMN and its activation to mutagens . These results indicate that the demethylation of DMN by the mixed-function oxidases is not the rate-limiting step in the metabolic activation of the carcinogen to mutagen(s), and that other microsomal or soluble enzymes may be involved. Food Chem Toxicol, 1982 Apr, 20(2), 171 - 5 Mutagenicity of commercial hair dyes in Salmonella typhimurium TA98; Albano G et al.; Commercial permanent hair-dye formulations containing p-phenylenediamine, resorcinol and aminophenols were incubated with hydrogen peroxide and then tested for their ability to induce reverse mutations in Salmonella typhimurium TA98 . Approximately half of the formulations (12 out of 25) gave positive results . The activity varied widely in degree and was observed only in the presence of an S-9 microsomal fraction from Aroclor-induced male rats . Five of the 12 positive formulations and one negative dye were administered topically to male rats; with one exception the urines of animals treated with the mutagenic hair dyes gave positive results in the presence of the S-9 mix. Mutat Res, 1982 Apr, 97(2), 103 - 16 Analysis of a method for testing azo dyes for mutagenic activity in Salmonella typhimurium in the presence of flavin mononucleotide and hamster liver S9; Prival MJ et al.; A protocol for assessing the mutagenic activity of azo dyes derived from mutagenic or potentially mutagenic aromatic amines was evaluated, using 4 model compounds . This protocol is based upon one developed in Sugimura's laboratory with modifications, including the use of flavin mononucleotide (FMN) rather than riboflavin to reduce the azo compounds to free amines, and hamster liver S9 rather then rat liver S9 for metabolic activation . The protocol developed differs from the standard Ames Salmonella plate incorporation assay in 5 ways: (1) uninduced hamster liver S9 rather than Aroclor 1254-induced rat liver S9 is used; (2) 150 microliters of S9 is used rather than the maximum of 50 microliter of S9 used in the standard assay; (3) FMN is added to the cofactor mix; (4) the cofactor mix is modified to include exogenous glucose 6-phosphate dehydrogenase, NADH, and 4 times the standard amount of glucose 6-phosphate; and (5) a 30-min "pre-incubation" step is used before addition of top agar . We found that each of these 5 changes is necessary for optimal mutagenic activity of azo dyes derived from the mutagenic aromatic amines benzidine, o-tolidine or o-dianisidine . The use of hamster liver S9 rather than rat liver S9 was also required for optimal mutagenic activity of benzidine itself . Rat liver S9 inhibited the ability of hamster S9 to activate benzidine to a mutagen . The presence in rat liver S9 of an inhibitor of the metabolic activation of benzidine may account for the failure of benzidine and a benzidine dye (Congo red) to be strongly mutagenic when tested with this type of S9. Mutat Res, 1982 Apr, 104(1-3), 9 - 15 Test-condition-dependent influence of harman and nonharman on benzo{a}pyrene mutagenesis in Salmonella; Riebe M et al.; The enhancing or decreasing effect of harman or norharman on benzo{a}pyrene mutagenesis depends mainly on the metabolizing system (S9) used . When mammalian activation was performed by using liver homogenates from mice induced by 3-methylcholanthrene, phenobarbital or Aroclor 1254, then the mutagenicity of benzo{a}pyrene in Salmonella typhimurium TA98 decreased upon addition of harman or norharman . In the presence of rat-liver homogenate induced by Aroclor 1154, however, harman enhanced the number of benzo{a}pyrene revertants, whereas norharman did not show any significant alteration of the benzo{a}pyrene mutagenicity . Further tests carried out with phenobarbital-induced mouse-liver homogenate showed that, within certain limits, neither variations of the amount of S9 extract nor the amount of the cofactors nor the relative proportions of the test substances had any influence on the antagonistic effect of harman or norharman on the benzo{a}pyrene mutagenesis. Mutat Res, 1982 Apr, 104(1-3), 61 - 6 Mutagenicity of nifurpirinol (P-7138) in Escherichia coli WP2 and Salmonella typhimurium TA100; Nakamura Y et al.; Nifurpirinol, 6-hydroxymethyl-2-{2-(5-nitro-2-furyl)vinyl}pyridine, which has been widely used as an antibacterial drug against diseases of fish, was found to be a potent mutagen . The mutagenic effect was dose-related, and the potencies were calculated to be 1.49 X 10(3), 7.24 X 10(4) and 8.49 X 10(5) revertants/1 X 10(-8) survivors at the concentration of 1 microgram/ml to :Escherichia coli B/r WP2, E . coli B/r WP2 hcr- and Salmonella typhimurium TA100, respectively, without metabolic activation . Nifurpirinol is susceptible to photodegradation, and its mutagenic activity to S . typhimurium TA100 was decreased to about one thousandth when the solution of Nifurpirinol was exposed to sunlight at room temperature for 4 h. J Clin Invest, 1982 Apr, 69(4), 959 - 70 Killing of gram-negative bacteria by polymorphonuclear leukocytes: role of an O2-independent bactericidal system; Weiss J et al.; Previous studies have suggested that a cationic bactericidal/permeability-increasing protein (BPI) present in both rabbit and human polymorphonuclear leukocytes is the principal O2-independent bactericidal agent of these cells toward several strains of Escherichia coli and Salmonella typhimurium (1978 . J . Biol . Chem . 253: 2664--2672; 1979 . J . Biol . Chem . 254: 11000--11009) . To further evaluate the possible role of this protein in the killing of gram-negative bacteria by polymorphonuclear leukocytes, we have measured the bactericidal activity of intact rabbit peritoneal exudate leukocytes under aerobic or anaerobic conditions and of intact human leukocytes from a patient with chronic granulomatous disease . Anaerobic conditions were created by flushing the cells under a nitrogen stream . Effective removal of oxygen was demonstrated by the inability of nitrogen-flushed leukocytes to mount a respiratory burst (measured as increased conversion of 1-{14C}glucose leads to 14CO2 or by superoxide production) during bacterial ingestion . At a bacteria/leukocyte ratio of 10:1, killing of gram-positive, BPI-resistant, Staphylococcus epidermidis is markedly impaired in the absence of oxygen (76.4 +/- 3.3% killing in room air, 29.2 +/- 8.2% killing in nitrogen) . Essentially all increased bacterial survival is intracellular . In contrast, both a nonopsonized rough strain (MR-10) and an opsonized smooth strain (MS) of S . typhimurium 395 are killed equally well in room air and nitrogen . A maximum of 70--80 MR-10 and 30--40 MS are killed per leukocyte either in the presence or absence of oxygen . There is no intracellular bacterial survival in either condition indicating that intracellular O2-independent bactericidal system(s) of rabbit polymorphonuclear leukocytes can at least match the leukocyte's ingestive capacity . Whole homogenates and crude acid extracts manifest similar bactericidal capacity toward S . typhimurium 395 . This activity can be accounted for by the BPI content of these cell fractions and is virtually eliminated by immune (anti-BPI), but not by preimmune goat IgG-rich fractions . Opsonization of smooth MS, required for bacterial killing by intact leukocytes, does not alter bacterial sensitivity to BPI in crude or purified form . Leukocytes of a patient with chronic granulomatous disease killed ingested S . typhimurium 396 MS nearly as well as did normal leukocytes . The bactericidal activity toward E . coli (J5) of crude acid extracts of the CGD and normal human leukocytes was virtually the same and was nearly completely inhibited by anti-BPI IgG-rich fractions, but not by preimmune IgG-rich fractions . These findings suggest that the killing of gram-negative bacteria such as S . typhimurium by intact polymorphonuclear leukocytes may also be attributed to the action of BPI. Infect Immun, 1982 Apr, 36(1), 271 - 6 Transfer of Salmonella resistance and delayed hypersensitivity with murine-derived transfer factor; Smith RA et