Publications

regulation of nonspecific acid phosphatase in salmonella: phon and phop genes.	mutations in salmonella typhimurium strains lacking nonspecific acid phosphatase mapped in two unlinked loci. one of these, phop, was cotransducible by phage p22 with purb, whereas the second, phon, was cotransducible by phage p1 with pura. mutants with temperature-sensitive nonspecific acid phosphatase activity (measured in whole cells) were also isolated. a phon mutant with thermolabile whole-cell activity was isolated directly from wild-type lt-2. several other mutants with temperature-sensit ...	1979	374361
rapid methods for generalized transduction of salmonella typhimurium mutants.	a procedure has been developed that allows the propagation of generalized transducing phage directly on cells growing on solid media. after the donor cells are killed with chloroform, the phage can be transferred directly to recipient cells and transductants can be selected.	1979	374369
genetic mapping of the chromosomal replication origin of salmonella typhimurium.	two hundred strains of escherichia coli harboring filv+ plasmids which carry a segment of the salmonella typhimurium chromosome were isolated independently. among them, two strains were found to harbor f' plasmids that are able to replicate in hfr cells of e. coli; i.e., they carry a site designated poh (permissive on hfr) of the s. typhimurium chromosome. the poh site is presumably identical with the replication origin (oric) of the bacterial chromosome. these two plasmids carry the dnaa-unca-r ...	1979	374380
properties of r plasmid r772 and the corresponding pilus-specific phage pr772.	r plasmid r772 was isolated from a strain of proteus mirabilis and is a self-transmissible p-1 incompatibility group plasmid having a molecular weight of about 27 x 10(6). it renders bacterial hosts resistant to kanamycin. phage pr772 was isolated as a phage dependent on the presence of r772 in bacterial hosts. it is hexagonal-shaped with a diameter of 53 nm, has a thick inner membrane and no tail. vaguely defined appendages are sometimes apparent at some vertices and the phage possesses double- ...	1979	374677
division and death rates of salmonella typhimurium inside macrophages: use of penicillin as a probe.	in mouse peritoneal macrophages infected in vitro with salmonella typhimurium the number of viable bacteria and the number of stainable bacteria detected by light microscopy both increased at similar rates with a doubling time of more than 1 h. antibiotics were not present; instead extracellular bacteria were removed by frequently rinsing the cells. the bacterial doubling time in the same medium in the absence of macrophages was about 20 min. penicillin added to macrophage monolayers rapidly ent ...	1979	374682
studies on salmonellosis in the house mouse, mus musculus.	salmonellae were isolated from the faeces from 17 of 170 (10%) wild house mice. salmonella typhimurium was isolated from 10, s. typhimurium, var. copenhagen from 2, s. thompson from 1, and s. muenchen from 4. it was concluded that house mice could be a reservoir of infection and play an important role in human and animal salmonellosis.	1979	374859
a combined testing protocol approach for mutagenicity testing.	the antischistosomal agent, hycanthone methanesulfonate (hms), was employed to illustrate the utility of carrying out several mutagenicity tests in a single concurrent animal experiment. several commonly used procedures that were successfully integrated into a multiple testing protocol included (1) metaphase analysis in bone marrow, (2) micronucleus test in bone marrow, (3) analysis of the urine for mutagenic constituents, and (4) the host-mediated assay using salmonella typhimurium. in addition ...	1979	375079
the mutagenic action of nitroimidazoles. iv. a comparison of the mutagenic action of several nitroimidazoles and some imidazoles.	the mutagenic action of 51 imidazoles was investigated. the fluctuation test of luria and delbrück was used, with klebsiella pneumoniae as test organism. 8 compounds, including 5 with a weak mutagenic action in the fluctuation test, were also investigated by the ames test in which salmonella typhimurium ta100 was used. of the 51 imidazoles examined, 33 were nitroimidazoles. 31 of the latter appeared to be mutagenic, whereas out of the 18 other imidazoles without a nitro group only 2 were mutagen ...	1979	375080
detection of mutagens in the urine of rats following topical application of hair dyes.	mutagens were detected in the urine of rats following topical application of two commercial oxidative-type hair dye preparations. the test system used was induction of back mutation with the bacterial tester strain ta1538, a histidine-dependent mutant of salmonella typhimurium. various quantities of dye were applied to the shortened hair on the backs of the test animals. the dye was allowed to remain on the hair for 20 min after application and was then removed by shampooing and thorough rinsing ...	1979	375082
hydrazines as mutagens in a histidine-requiring auxotroph of salmonella typhimurium.	hydrazines have been found naturally in tobacco and mushrooms. other hydrazines are used in industry, medicine, and agriculture. although about 38 hydrazines are carcinogenic, few, if any, have been tested successfully in rapid bacterial mutagenesis assays. we have utilized a tester strain of salmonella typhimurium (ta1530) in order to determine the mutagenic activity of a number of hydrazines and related compounds. this strain is thus shown to be effective as a tester organism for the facile de ...	1979	375083
comparison of the induction by cigarette smoke condensates of sister-chromatid exchanges in chinese hamster cells and of mutations in salmonella typhimurium.	three cigarette smoke condensates were tested for the induction of sister-chromatid exchanges in ovary cells of the chinese hamster and for mutations in salmonella typhimurium. in the sister-chromatid exchange test an effect was obtained that was not enhanced by the inclusion of a system for metabolic activation. in the salmonella test, an effect was only obtained by including rat-liver homogenates derived from rats treated with inducers of the enzyme systems necessary for metabolic activation. ...	1979	375084
aflatoxin b1 mutagenesis, dna binding, and adduct formation in salmonella typhimurium.	salmonella typhimurium strain tm677 was mutagenized with aflatoxin b1 (afb1) in liquid suspension culture in the presence of a rat liver postmitochondrial supernatant. forward mutation to 8-azaguanine resistance was measured in the treated cultures and was found to increase linearly with afb1 concentration. dna purified from mutagenized cells was analyzed for afb1 adduct formation by high-pressure liquid chromatography after adduct liberation. afb1 exposures at 0.16 and 0.32 micrometer for 35 mi ...	1979	375236
physical factors affecting the mutagenicity of fly ash from a coal-fired power plant.	the two finest, most respirable coal fly ash fractions collected from the smokestack of a power plant were more mutagenic than two coarser fractions. mutagenicity was evaluated in the histidine-requiring bacterial strains ta 1538, ta 98, and ta 100 of salmonella typhimurium. ash samples collected from the hoppers of an electrostatic precipitator in the plant were not mutagenic. the mutagens in coal fly ash were resistant to x-ray or ultraviolet irradiation, possibly as a result of stabilization ...	1979	375394
mutagenicity of inhalation anaesthetics: trichloroethylene, divinyl ether, nitrous oxide and cyclopropane.	the mutagenic potential of trichloroethylene, divinyl ether, nitrous oxide and cyclopropane was assessed in vitro by microbial assay employing two histidine-dependent strains of salmonella typhimurium, ta1535 and ta100. anaesthetic agents in various concentrations were incubated with bacteria in the presence or absence of an enzyme system prepared from enzyme-induced rat liver. nitrous oxide and cyclopropane were not mutagenic, whereas divinyl ether gave a strongly positive response. results for ...	1979	375954
effect of 2-nitrofluorene, 1,2-dimethylhydrazine, and azoxymethane on salmonella typhimurium mutants in the gastrointestinal tract of gnotobiotic rats.		1979	376114
carcinogenicity of 2-hydroxybenzo(a)pyrene and 6-hydroxybenzo(a)pyrene in newborn mice.	benzo(a)pyrene (bp), 2-hydroxybenzo(a)pyrene (2-hobp), and 6-hydroxybenzo(a)pyrene (6-hobp) were tested for tumorigenicity by i.p. injection into newborn mice. the mice were treated sequentially with 200, 400, and 800 nmol of compound on the first, eighth and fifteenth day of life, and the animals were killed at 24 weeks of age. treatment with 2-hobp caused about 4-fold more pulmonary tumors than bp, while 6-hobp had little or no tumorigenic activity. newborn mice treated with 2-hobp, bp, and 6- ...	1979	376121
evaluation of feasibility of mutagenic testing of shale oil products and effluents.	in an effort to gather preliminary information on the potential genetic hazards of proposed or existing oil shale technologies, we have begun a correlated analytical and genetic analysis of a number of test materials. the work is divided into two phases: one deals with known compounds expected to occur in the environment through shale oil production or use; the other deals with actual samples from existing or experimental processes. a fractionation procedure has been applied to crude product and ...	1979	376308
use of ames test in evaluation of shale oil fractions.	conditions that affect the sensitivity of the ames assay of complex hydrocarbon mixtures derived from shale oil were studied. two fractions, one enriched in polynuclear aromatic compounds (pna fraction), and a second fraction enriched in aromatic and heterocyclic amines (basic fraction), were selected for most of this work because of their comparatively high mutagenicity (i.e., compared with raw shale oil). the crude shale oil, as well as the basic, pna, and tar fractions were mutagenic against ...	1979	376309
characterization of porins from the outer membrane of salmonella typhimurium. 1. chemical analysis.	the three species of channel-forming outer membrane proteins, porins, have been purified to homogeneity from mutant strains of salmonella typhimurium which produce single species of porin. purification was by stepwise solubilization with dodecylsulfate or guanidine thiocyanate, gel filtration, and preparative gel electrophoresis. amino acid compositions and tryptic peptide maps of the three species of porins showed close resemblance, but at the same time clear differences among them. the number ...	1979	376310
characterization of porins from the outer membrane of salmonella typhimurium. 2. physical properties of the functional oligomeric aggregates.	we have purified to homogeneity, from mutant strains of salmonella typhimurium, the small oligomers of porin that confer permeability channels to artificial vesicle membranes reconstituted from phospholipids and lipopolysaccharide. the molecular weights of the porin oligomers from the strains sh5551 and sh6017 appeared to be 130000 and 125000, respectively, and those of the monomers were 41000 and 37500, respectively, when determined by sedimentation equilibrium in the presence of dodecylsulfate ...	1979	376311
construction of an m13 histidine-transducing phage: a single-stranded cloning vehicle with one ecori site.	in order to create a ready source of single-stranded dna for dna sequence determination by the dideoxy chain-termination method, the promoter-proximal part of the histidine operon, the hisogd region of salmonella typhimurium, was cloned onto the single-stranded phage m13. both orientations of the his dna were cloned to supply dna template for sequencing of each strand. insertion was achieved at an haeiii site in the intergenic region (ir) of m13, and a single ecori site was purposely regenerated ...	1979	376403
isolation of salmonella paratyphi b and salmonella typhimurium from guineapigs.		1979	376438
pseudouridylation of trnas and its role in regulation in salmonella typhimurium.		1979	376505
a survey of trimethoprim resistance in the enteric bacterial flora of farm animals.	for 29 months the veterinary investigation centres, covering the whole of great britain, forwarded trimethoprim-resistant gram negative enteric bacteria to the wellcome research laboratories. these were examined for degree of resistance, presence and type of r factors. trimethoprim resistance was found in 0.6% of the total number of strains examined by the veterinary investigation centres. trimethoprim r factors were demonstrated in one quarter of the resistant strains, and r factors were found ...	1979	376699
the incidence of salmonella in random-source cats purchased for use in research.	in research facilities, cats are routinely ignored as a potential source of salmonella infection. over a period of 18 months, 142 cats received from commercial vendors for use in research were screened for enteric salmonella. salmonella was isolated from 15 animals, an incidence of 10.6%. five (29%) of the 17 shipments contained animals that were positive for salmonella. the serotypes isolated were salmonella derby, salmonella typhimurium, salmonella anatum, salmonella enteritidis, and salmonell ...	1979	376759
replication and maturation of phage p22 in a mutant of salmonella typhimurium temperature sensitive in initiation of dna replication.	tb37 is a dna a-mutant of salmonella typhimurium in which the initiation of dna replication at the origin is stopped at 42 degrees c. dna synthesis in uninfected cells of this strain and in cells infected by phage p22 was followed by the pulse labelling technique. dna replication ceases completely after about 50 minutes at the high temperature. after lytic infection with p22 (c2) at this time, dna synthesis starts immediately and increases at a rate well comparable to the permissive control. obv ...	1979	377015
amino acid sequence of atp phosphoribosyltransferase of salmonella typhimurium.	the amino acid sequence of atp phosphoribosyltransferase [1-(5'-phosphoribosyl)-atp:pyrophosphate phosphoribosyltransferase, ec 2.4.2.17] of salmonella typhimurium has been determined. the amino acid sequence analysis was carried out with a combination of manual and automated methods. it was complemented by dna sequence analysis (done in another laboratory) of the hisg gene, which codes for it. the subunit polypeptide chain contains 299 amino acid residues and has a molecular weight of 33,216. t ...	1979	377278
[functional liver tests in rabbits with experimental salmonellosis induced by salmonella typhi murium (author's transl)].		1979	377421
[mutagenic activity of propoxur, carbaryl and their nitroso derivatives: induction of reversion in salmonella typhimurium].		1979	377454
vivo clearance of enteric bacteria from the hemolymph of the hard clam and the american oyster.	american oysters, crassostrea virginica, and hard clams, mercenaria mercenaria, were experimentally contaminated with escherichia coli, salmonella typhimurium, and shigella flexneri either by intracardial injection or via the natural route of ingestion. bacterial inactivation in the hemolymph was monitored for 72 h after exposure to these enteric pathogens at 20 and 6 degrees c. at 6 degrees c, both mean bacterial uptake by ingestion and subsequent clearance was singificantly lower that at 20 de ...	1979	378127
mutagenicity of the mycotoxin emodin in the salmonella/microsome system.	the mycotoxin emodin was found to be a frameshift mutagen for salmonella typhimurium strain ta 1537 after metabolic activation in a mammalian microsome system.	1979	378132
studies on the subunits of the anthranilate synthetase-phosphoribosyltransferase enzyme complex from salmonella typhimurium.		1979	378135
[mutagenic effect of a tetrahydrodiazopyrene derivative on bacteria].	mutagenic action of 3,7-diamino-4,9-dioxy-5,10-dioxo-4,5,9,10-tetrahydro-4,9-diazapiren (dddtdp) was shown using indicator strains salmonella typhimurium ta 1534, ta 1536, ta 1537, ta 1538. the drug-induced mutations in strains ta 1534 and ta 1538, and it can be used as a positive control in testing mutagens capable of inducing frameshift mutations. no significant differences was observed between dddtdp effects on strains ta 1534 and ta 1538 which did or did not bear rfa mutation causing defects ...	1979	378766
bactericidal activity of fractionated granule contents from human polymorphonuclear leukocytes.	proteins from human polymorphonuclear leukocyte granules were extracted with 0.2 m acetate, ph 4.0, and fractionated by sephadex g-100 column chromatography. the fractions demonstrated selective bactericidal action against a deep rough cell wall mutant of escherichia coli o111:b4 with rough lipopolysacharide and cell wall mutants of salmonella typhimurium lt-2 with lipoplysacharide of ra, rc, rd1, rd2, and re types. smooth parent strains were most resistant to the bactericidal action. fractions ...	1979	378830
mouse protective capabilities of escherichia coli hybrids expressing salmonella typhi antigens.	an escherichia coli hybrid, f1061, expressing salmonella typhi somatic antigens 9 and 12, and a derivative of this hybrid, e. coli hybrid wr3078, expressing the s. typhi vi antigen in addition to somatic antigens 9 and 12, were compared with s. typhi ty2 in experiments to test their ability, as live vaccines, to protect swiss white mice against death from challenge with a mouse-virulent salmonella typhimurium hybrid expressing the s. typhi antigens 9, 12, vi, and d. when the live, vaccinating or ...	1979	378849
apparent involvement of purines in the control of expression of salmonella typhimurium pyr genes: analysis of a leaky guab mutant resistant to pyrimidine analogs.	a leaky guab mutant of salmonella typhimurium lt-2 was obtained during a selection for mutants resistant to a combination of the two pyrimidine analogs, 5-fluorouracil and 5-fluorouridine. in the absence of exogenous guanine compounds, the growth rate of this mutant is limited by the endogenous supply of guanine nucleotides due to a defective inosine 5'-monophosphate dehydrogenase. under these conditions the guanosine 5'-triphosphate pool is about 20% of normal, the cytidine 5'-triphosphate pool ...	1979	378934
functional homology of chemotaxis genes in escherichia coli and salmonella typhimurium.	generally nonchemotactic mutants of escherichia coli and salmonella typhimurium were analyzed by interspecies complementation tests to determine the functional correspondence between the che genes of these two organisms. the e. coli che region was introduced into salmonella recipients by means of a series of f-prime elements. wild-type che genes of e. coli f'420 complemented all che mutants of salmonella except ches, chev, and a subclass of cheu. a series of tester episomes carrying e. coli che ...	1979	378950
transaminase b from escherichia coli: quaternary structure, amino-terminal sequence, substrate specificity, and absence of a separate valine-alpha-ketoglutarate activity.	transaminase b (branched-chain amino acid aminotransferase, ec 2.6.1.42), the ilve gene product, was purified to apparent homogeneity from an escherichia coli k-12 strain which carries the ilve gene both on the host chromosome and on a plasmid. the oligomeric structure of the enzyme, as determined by analytical ultracentrifugation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was confirmed to be that of a hexamer with a molecular weight of about 182,000 and apparently identical ...	1979	378964
mutants defective in the 33k outer membrane protein of salmonella typhimurium.	salmonella typhimurium lt2 lines, if phenotypically rough, are fully sensitive to bacteriocin 4-59, produced by salmonella canastel strain sl1712. bacteriocin-resistant mutants fell into three classes. those resistant to phage es18 and to albomycin proved to be mutants of class chr (equivalent to tonb of escherichia coli); these mutants still adsorb the bacteriocin and so are classified as tolerant. another class of (incompletely) tolerant mutants was resistant to phage ph51; their envelope frac ...	1979	378966
specific inactivator of flagellar reversal in salmonella typhimurium.	specific inhibition of flagellar rotation reversal was observed after exposure of chemotactic salmonella typhimurium to citrate autoclaved at neutral ph. the presence of a rotation reversal inactivator was established in autoclaved citrate-containing media and nutrient broth. since modulation of flagellar rotation by attractants and repellents is the basis of chemotactic behavior, a specific inhibitor of rotation reversal, which is essential for tumble generation, provides a useful probe into th ...	1979	378971
chromosomal location and expression of the structural gene for major outer membrane protein ia of escherichia coli k-12 and of the homologous gene of salmonella typhimurium.	the gene determining the structure of a major outer membrane protein of escherichia coli, protein ia, has been located between serc and pyrd, at the min 21 region of the linkage map. this is based on the isolation and characterization of e. coli-salmonella typhimurium intergeneric hybrids as well as analyses of a mutation (ompf2) affecting the formation of protein ia. when the serc region of the s. typhimurium chromosome was transduced by phage p1 into e. coli, two classes of transductants were ...	1979	378974
suppression of a deletion mutation in the glutamine amidotransferase region of the salmonella typhimurium trpd gene by mutations in phea and tyra.	prototrophic revertants of a trpd deletion mutant that lacks the glutamine amidotransferase domain of the bifunctional component ii subunit of the anthranilate synthetase-phosphoribosyltransferase complex have been found to arise by the occurrence of sublethal missense mutations in either the phea or tyra loci. such suppressor mutations were obtained directly by mutation of the wild-type phea gene as well as indirectly by partial reversion of a variety of nonleaky phea and tyra mutations. the su ...	1979	378978
ultrastructure of the outer membrane of salmonella typhimurium bacteriocin-resistant mutants deficient in the 33k protein.	outer membrane mutants of salmonella typhimurium deficient in one, two, or three of the 33,000-dalton (33k), 34k, and 36k outer membrane proteins (7) were studied by using thin sectioning and freeze-fracturing electron microscopy techniques. the outer concave fracture face of all mutants deficient in the 33k protein had numerous particleless patches. in contrast to all previously examined 34k to 36k-deficient mutants, the 33k-deficient mutants showed marked heterogeneity in the size and distribu ...	1979	378982
ames test of 1-(x-phenyl)-3,3-dialkyltriazenes. a quantitative structure-activity study.	the mutagenicity of 1-(x-phenyl)-3,3-dialkyltriazenes was tested in the ames test using salmonella typhimurium ta92. the following quantitative structure-activity relationship (qsar) was formulated: log 1/c = 1.09 log p -1.63 sigma+ + 5.58. in this expression, c is the molar concentration of triazene producing 30 mutations/10(8) bacteria above background. this equation is based on 17 congeners and has a correlation coefficient of 0.974. the qsar for mutagenicity is compared with qsar for antileu ...	1979	379331
mutation of human cells by kerosene soot.	the polycyclic aromatic hydrocarbon fraction of a kerosene soot induced forward mutation in human diploid lymphoblasts when coincubated with sprague-dawley rat liver postmitochondrial supernatant. two components of the kerosene soot extract, benzo[a]pyrene (bp) and cyclopenta[cd]pyrene (cp), were also tested. tp was not mutagenic at the concentration found in the soot extract, although it was active at higher concentrations. the amount of cp present could account for approximately 8% of the tota ...	1979	379398
alterations of lipid metabolism in mice injected with endotoxin.	some alterations in lipid metabolism in mice were observed by the intraperitoneal injection of endotoxin from salmonella typhimurium. the content of serum triglyceride increased markedly in poisoned mice 16-24 hr postintoxication. the level of free fatty acid (ffa) in the serum of endotoxin-administered mice decreased in inverse proportion to an increase in the injected dose of endotoxin. the electrophoretic analysis of the serum lipoprotein on cellulose acetate membrane showed that pre beta-lip ...	1979	379551
the effects of the ultraviolet-protecting plasmids pkm101 and r205 on dna polymerase i activity in escherichia coli k-12.	the mutagenesis- and repair-enhancing plasmids pkm101 and r205 were introduced into a series of esherichia coli k-12 pola mutants including two temperature-sensitive mutants. polymerase levels in extracts of these strains were assayed using an activated dna template. in none of the cases did the presence of the plasmid in the strains change either the initial rate of incorporation of [3h]thymidine triphosphate into acid-soluble material or the subsequent degradation of the template at longer rea ...	1979	379622
the mutagenicities of safrole, estragole, eugenol, trans-anethole, and some of their known or possible metabolites for salmonella typhimurium mutants.	safrole, estragole, anethole, and eugenol and some of their known or possible metabolites were tested for mutagenic activity for s. typhimurium ta1535, ta100, and ta98. highly purified 1'-hydroxyestragole and 1'-hydroxysafrole were mutagenic (approximately 15 and 10 revertants/micromole, respectively) for strain ta100 in the absence of fortified liver microsomes; trans-anethole and estragole appeared to have very weak activity. 3'-hydroxyanethole was too toxic for an adequate test. supplementati ...	1979	379623
reduction in mutagenicity of cigarette smoke condensate by added sugars.	the effects of adding sugars to high- and low-tar cigarettes on the mutagenicity of their smoke condensates were studied using salmonella typhimurium ta100 and ta98 with and without metabolic activation. the sugars tested were glucose, fructose, galactose, sorbitol, sucrose and lactose. the lowest mutagenicities observed with these sugars per mg of smoke condensate assayed on ta98 with metabolic activation were 37% (high-tar cigarettes) and 22% (low-tar cigaretts) of that of smoke condensate fro ...	1979	379624
mutagenicity of 43 structurally related heterocyclic compounds and its relationship to their carcinogenicity.	43 heteropolycyclic compounds belonging to a homologous series were investigated for mutagenicity. the results are compared with carcinogenicity data obtained with the same batches of compounds under conditions identical for all of them. mutagenicity was tested in the ames test with salmonella typhimurium strains ta1535, ta1537 and ta100 in the presence and absence of liver 10 000 g supernatant from rats treated with aroclor 1254. carcinogenicity was tested by injection of the compounds into sub ...	1979	379627
delta 1-tetrahydrocannabinol and 1 alpha, 2 alpha-epoxyhexahydrocannabinol: mutagenicity investigation in the ames test.	1,2-epoxyhexahydrocannabinol is a metabolite of delta 1-tetrahydrocannabinol. because many epoxides are mutagens, we investigated 1,2-epoxyhexahydrocannabinol as well as delta 1-tetrahydrocannabinol for mutagenicity with salmonella typhimurium ta1535, ta1537, ta98 and ta100 in the presence and in the absence of s9 mix from liver homogenate of rats treated with aroclor 1254. additionally, an epoxide hydratase inhibitor was used in some experiments. whereas several other epoxides and further posit ...	1979	379628
mutagenicity of phenanthrene and phenanthrene k-region derivatives.	phenanthrene and 9 k-region derivatives, most of them potential metabolites of phenanthrene, were tested for mutagenicity by the reversion of histidine-dependent salmonella typhimurium ta1535, ta1537, ta1538, ta98 and ta100 and the rec assay with bacillus subtilis h17 and m45. the strongest mutagenic effects in the reversion assay were observed with phenanthrene 9,10-oxide, 9-hydroxyphenanthrene and n-benzyl-phenanthrene-9,10-imine. interestingly, the mutagenic potency of the arene imine was sim ...	1979	379629
antioxidants reduce the mutagenic effect of malonaldehyde and beta-propiolactone. part ix. antioxidants and cancer.	increasing concentrations of malonaldehyde and beta-propiolactone were increasingly mutagenic with 7 mutants of salmonella typhimurium, 5 of which mutated bya frameshift mechanism and 2 of which mutated through base-pair substitution. the antioxidants vitamin c, vitamin e, selenium and butylated hydroxytoluene (bht) at 3 logarithmic concentrations markedly reduced mutagenesis in those strains which mutated by frameshift mechanism.	1979	379630
mutagenic action of a series of epoxides.	the mutagenicity of a series of 13 epoxide compounds was studied using a bacterial plate assay system. the histidine-dependent tester strains ta98 (for frameshift mutagens) and ta100 (for base-pair substitution mutagens) of salmonella typhimurium were used. mutagenicity was evaluated both with and without the additon of rat liver microsomal extract. dieldrin, diglycidyl ether of bis phenol a and 3 of its homologues were not mutagenic. allyl glycidyl ether, n-butyl glycidyl ether, vinly cyclohexe ...	1979	379632
the mutagenicity of halogenated alkanols and their phosphoric acid esters for salmonella typhimurium.	9 halogenated alkanols, 9 corresponding tris (haloalkyl)phosphates, and 2 bis-(2,3-dibromopropyl)phosphate salts were evaluated for mutagenicity against salmonella typhimurium ta98, ta100, ta1535, ta1537 and ta1538, with and without rat liver in vitro metabolic activation system (s9 mix). most of the test samples showed mutagenic activity in the strains ta100 and ta1535, but not in the strains ta98, ta1537 and ta1538. in general, the mutagenic activities of the phosphates obtained with s9 mix we ...	1979	379633
mutagenicity test of dyes used in cosmetics with the salmonella/mammalian-microsome test.	37 dyes including 3 anthraquinone, 22 azo; 5 xanthene, 5 fluorandiol, and 2 thioindigo dyes, were tested for mutagenic potential with the salmonella/mammalian-microsome test. two frame-shift histidine mutants (ta1537 and ta98) and two base-pair substituted histidine mutants (ta1535 and ta100) of salmonella typhimurium were employed. both the spot test and the plate-incorporation assay indicated that one azo dye, d&c orange no. 17, was mutagenic with three of the bacterial test strains. the mutag ...	1979	379635
mutagenicity of cyclic nitrosamines in salmonella typhimurium: effect of ring size.	mutagenicity of cyclic nitrosamines with varying carcinogenic potentials was assayed in the salmonella histidine-reversion system. mutagenicity in the pour-plate assay was compared with that in the liquid pre-incubation test. the smaller ring compounds (nitrosoazetidine, nitrosopyrrolidine, and nitrosopiperidine) exhibited a similar effect in both assays. the large ring compounds (nitrosohexamethyleneimine, nitrosoheptamethyleneimine, nitrosooctamethyleneimine, and nitrosododecamethyleneimine) w ...	1979	379636
mutagenicity of p-nitrophenyl-p'-guanidinobenzoate on salmonella typhimurium strain ta98.		1979	379637
mutagenicity of 7-iodo and 7-fluoro derivatives of n-hydroxy-and n-acetoxy-n-2-acetylaminofluorene in the salmonella typhimurium assay.		1979	379638
[mutagenicity for salmonella typhimurium (ames test) of some trichomonacides].		1979	379709
[effect of protein in the feed on the resistance of poultry artificially infected with salmonella galinarum pullorum and salmonella typhimurium].	studied is the effect of the low protein level in rations of birds, experimentally infected with salmonella gallinarum-pullorum and salmonella typhimurium. birds of different ages of the leghorn and cornish breeds are included in the experiments. results obtained from the experiments indicate that the lowered level of protein in rations to young birds at the age of five months makes them more resistant to salmonella infection. this dependence is markedly demonstrated in particular in the case of ...	1978	380135
[change in the biological properties of salmonellae in acquiring resistance to chloramphenicol].	mutants of salmonella typhimurium and salmonella abony resistant to 40 microgram/ml of chloramphenicol were obtained during selection according to the method of szybalski on hottinger broth with increasing concentrations of the antibiotic. by the colony morphology the mutants were divided into 4 groups. the study of the mutant biological properties revealed changes in the growth rate characterized by elongation of the lag-phase and exponential phase, changes in the biochemical activity evident f ...	1979	380452
effect of a salmonella group h1 r factor on virulence and response of infections to antimicrobial therapy.	a group h1 r factor encoding resistance to chloramphenicol, streptomycin, sulfonamide, and tetracycline was transferred into salmonella typhimurium lt-2. the virulence of lt-2 for mice, as assessed by intraperitoneal 50% lethal dose and the number of organisms in the spleen, was not affected by the r factor. on the other hand, the r factor conferred resistance in mouse infections to therapy with chloramphenicol and trimethoprim plus sulfamethoxazole.	1979	380460
relaxed control of rna synthesis during nutritional shiftdowns of hisu mutant of salmonella typhimurium.		1979	380566
[subdural empyema due to salmonella typhimurium. analysis of a case].	the case was that of an infant with congenital hydrocephalus who developed subdural empyema. the most outstanding items were, the age of the patient (18 months), the identification of salmonella typhimurium, a germ rarely described responsible for this pathology, the absence of anacrobe germs and the possible hematogenous dissemination from the digestive tract when the port of entry usually associated is the infection of the paranasal sinuses. the most useful method for study was the computerize ...	1979	380596
[cytophilic immunoglobulins on the surface of neutrophilic granulocytes in mice perorally immunized with a live vaccine made from the supressor revertant s. typhimurium rev 8].	the reaction of the spleen cell migration inhibition in the presence of monospecific antisera against mouse g, a and m immunoglobulins was used to detect cytophilic antibodies on the surface of mouse granulocytes. the oral administration of acr live vaccine from suppressor revertant salmonella typhimurium rev. 8 protected the mice against infection induced by virulent species of mouse. salmonella typhimurium. the immunized mice showed an increase in cytophilic igg on the surface of neutrophile g ...	1979	380686
metabolic and mutagenicity studies on ddt and 15 derivatives. detection of 1,1-bis(p-chlorophenyl)-2,2-dichloroethane and 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethyl acetate (kelthane acetate) as mutagens in salmonella typhimurium and of 1,1-bis(p-chlorophenyl) ethylene oxide, a likely metabolite, as an alkylating agent.	using a novel in vitro technique, whereby microsomal enzymes were embedded in an agar layer to prolong their viability, 1,1-bis(p-chlorophenyl) ethylene(ddnu), a mammalian metabolite of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (ddt), was converted by microsomal mono-oxygenases of mouse liver into 1,1-bis(p-chlorophenyl)-1,2-ethanediol (ddnu-diol). the putative epoxide intermediate, 1,1-bis(p-chlorophenyl)ethylene oxide (ddnu-oxide), a new compound, was synthesized; it showed weak alkylating ...	1979	380827
mechanisms of action of carcinogenic aromatic amines: an investigation using mutagenesis in bacteria.	the mutagenicities of groups of n-acetoxy-n-arylacetamides, nitroarenes, arylamides and arylamines were determined in the salmonella typhimurium tester stains ta98, ta1538, ta100, ta1535 and ta1537. three broad classes of mutagenic activity were found, interpreted as follows: class a, including 2-naphthylamine, produced essentially only base-pair substitution without induction of error-prone repair; class b, including 4-aminobiphenyl, caused consideration induction of error-prone repair, accompa ...	1979	380829
induction of thymocytotoxic autoantibodies after injection of bacterial lipopolysaccharides in mice.	the injection of bacterial lipopolysaccharides (salmonella typhimurium and escherichia coli lps) has been shown to induce thymocytotoxic autoantibodies in various strains of mice (c57bl/6, balb/c, dba/2, akr, a/j and c3heb/fej). titers up to l:16 were observed. such antibodies did not develop in c3h/hej mice which are low responders to lps. the thymocytotoxic antibodies had the following characteristics: (a) 2-mercaptoethanol sensitivity, (b) optimal reactivity at 4 degrees c, (c) cytotoxicity f ...	1979	381011
natural resistance to salmonella typhimurium in different inbred mouse strains.	the mechanisms of natural resistance to intravenous challenge with salmonella typhimurium c5 are complex. ld50 determinations showed inbred mouse strains of low, intermediate and high natural resistance, with balb/c and b10 strains the most susceptible, a/j the most resistant. delayed (footpad) hypersensitivity was not by itself a measure of natural resistance. resistant mouse strains sensitized either s.c. or i.v. with an attenuated salmonella strain showed positive 48 h footpad reactions when ...	1979	381178
genetics of natural resistance to salmonellae in mice.	the genetics of natural resistance to salmonellae were studied in f1 hybrid and backcross mice. overall resistance to salmonella typhimurium c5 is complex, but one parameter, the early net growth rate of the organism in vivo, is controlled by a single autosomal gene or cluster of genes. 'slow' net growth rate is necessary but insufficient, for resistance to s. typhimurium c5. resistance requires the participation of other mechanisms, detectable by the end of the first week, which presumably invo ...	1979	381179
the natural resistance of radiation chimeras to s. typhimurium c5.	differences in the in vivo net growth rate of salmonella typhimurium c5 during the first week of infection in different mouse strains are controlled by a single autosomal gene. in lethally irradiated mice repopulated with semi-allogeneic bone marrow, the early net growth rate shows the phenotype of the donor of the bone marrow cell and not the phenotype of the irradiated recipient. thus, genetically controlled differences in in vivo bacterial net growth rate are a consequence of mechanisms opera ...	1979	381180
identification of protective cell surface proteins in ribosomal fractions from salmonella typhimurium.	cell surface antigen preparations from salmonella typhimurium sr-11 prepared by either trichloroacetic acid extraction or boiling in sodium dodecyl sulfate were able to protect c3h/hej, c3h/hedub, and a/j mice. some of the proteins found in these preparations were shown to exist in the protective ribosomal fraction isolated from s. typhimurium sr-11. passage of ribosomes isolated from s. typhimurium sr-11 and 6707 through a sepharose 2b column removed the protective immunogen from 6707 ribosomes ...	1979	381202
immunotherapy of guinea pig line 10 hepatoma with nonliving bcg cells in aqueous medium.	killed bcg cells suspended in 1.5% carboxymethylcellulose cured guinea pigs with established line 10 tumors in a high percentage of cases. the bacterial preparation of bcg in carboxymethylcellulose displayed a stronger tumor regressive activity and the process of healing was accelerated when endotoxin from a rough (re) strain of salmonella typhimurium was added to the bcg bacilli.	1979	381203
the removal of 14c labeled endotoxin by activated charcoal.	endotoxin shock due to gram-negative enteric bacteria is of major medical concern with an estimated 100,000 fatalities in the united states per year. an effective therapy for endotoxin shock, particularly in combination with significant liver damage, has not been available to date. since activated charcoal is known as a universal sorbent, the use of activated charcoal in a hemoperfusion apparatus to remove endotoxin has interesting possibilities. current assays for endotoxin are inadequate. the ...	1979	381215
evaluation of the mutagenicity of aminoglycoside antibiotics in salmonella typhimurium and saccharomyces cerevisiae.	the mutagenicity of aminoglycoside antibiotics (km, akm, dkb, rsm, amk, gm, tob) has been studied in cells of the bacteria salmonella typhimurium and in the yeast saccharomyces cerevisiae. the bacterial strains (ames') monitor reverse mutation (point mutation) and the yeast strain d5 monitors mitotic crossing-over, mitotic gene conversion and point mutation. none of these antibiotics demonstrated any mutagenic activities in either the bacteria or the yeast.	1979	381273
biotyping and colicine typing of salmonella typhimurium strains of phage type 141 isolated in scotland.	cultures of salmonella typhimurium (551 strains) of phage type 141 isolated in scotland from 1965 to 1977 were examined for biotype and colicine type. three main biotype clones were recognised: if (30 strains), 9f (507 strains) and 31bd (11 strains) with subtype variants 9bf (1 strain), 9cf (1 strain) and 31b (1 strain). the contribution made by each biotype clone to outbreaks in scotland was analysed. the findings confirmed the distinctness of the three biotype clones within the single phage ty ...	1979	381665
nucleotide sequence of the trpc-trpb intercistronic region from salmonella typhimurium.		1979	381671
a longitudinal epizootiological study of salmonella infection on a piggery: a study on the mode of contamination by biotyping of salmonella typhimurium and by the antibiogram.		1979	381741
evaluation of three metabolic activation systems by a forward mutation assay in salmonella.	the strain sv3 of salmonella typhimurium was used as the indicator bacterium in the intrasanguineous host-mediated mutagenicity assay. bacterial distribution and spontaneous mutation frequency were determined after intravenous injection of sv3 into cd1 male mice. bacteria were cleared at an exponential rate from the blood stream and recovered mainly from the liver and in smaller quantities from the lungs and kidneys. no bactericidal effect was observed during incubation within the animal, and ba ...	1979	381907
mutagenic activity of propylene oxide in bacterial and mammalian systems.	propylene oxide is used extensively in the chemical and food manufacturing industries, but relatively little is known of its ability to interact with genetic material. studies were undertaken to investigate its ability to induce gene mutations and primary dna damage in bacteria and chromosomal damage in mammalian cells. the induction of base-substitution mutations was demonstrated in spot tests with strains of salmonella typhimurium and escherichia coli at 700 micrograms/plate of propylene oxide ...	1979	381910
diethylstilbestrol and 11 derivatives: a mutagenicity study with salmonella typhimurium.	diethylstilbestrol was tested for mutagenicity with his- s. typhimurium strains under 10 different matabolic situations (no exogenous metabolizing system; s9 mix from liver homogenate of rats induced with aroclor 1254, with or without inhibition of epoxide hydratase; liver and/or kidney s9 mix from control or hamsters treated with aroclor 1254; horse-radish peroxidase + h2o2). under none of these conditions did diethylstilbestrol give any indication of a mutagenic effect. furthermore, 11 metabol ...	1979	381911
chemicals which revert all commonly used salmonella typhimurium tester strains.		1979	381916
natulan induces forward mutations to l-arabinose-resistance in salmonella typhimurium.		1979	381917
the mutagenic activity of anti-cancer drugs and the urine of rats given these drugs.	twenty-one anti-cancer drugs have been tested for their ability to cause mutations in salmonella typhimurium test strains in the salmonella/microsome mutagenicity test. nine of the 21 anticancer drugs showed this ability: cyclophosphmide, nitromin, thio-tepa, busulfan, 6-mercaptopurine, neocarzinostatin, daunomycin, adriamycin and estramustine phosphate. seven of these 9 mutagenic drugs were injected continuously into the jugular veins of rats. urine was collected through a cystostomy tube and t ...	1979	382571
immunogenic complexes obtained from salmonella typhi-murium and salmonella typhi ty2 by the bacterial acetone powder method.	an immunogenic complex was isolated from salmonella typhi-murium and another one from salmonella typhi ty2. both were prepared by the bacterial acetone powder method which eliminated the cell wall, the dna almost completely and the membrane phospholipids. the complexes were denominated "new vaccines". the s. typhi-murium new vaccine induced, even at doses of 0.5 microgram dry weight per mouse, a high degree of protection against the challenge of the virulent microorganism. by immunoelectrophores ...	1979	382951
mutagenic activity of cytostatic methyl hydrazones with different strains of salmonella typhimurium.	experiments are performed to ascertain the mutagenic properties of four new cytostatic methyl-hydrazones in the ames test using different strains of salmonella typhimurium. as could be demonstrated all four hydrazones are mutagenic per se without a metabolic activation through rat liver microsomes (s-9 fraction). whereas the beta-chloroethyl hydrazones b1 and b2 cause a base-pair substitution with the strains ta100 and ta1535 the methyl-hydrazones eb4 and cyb4 both cause base-pair substitution w ...	1979	383045
bacteriophage p22 development is temperature sensitive in thiolutin resistant mutants of salmonella typhimurium.		1979	383075
purification and properties of a citrate-binding transport component, the c protein of salmonella typhimurium.	salmonella typhimurium was shown to contain a citrate-binding protein (c protein) which was purified to homogeneity from the periplasmic fraction released by cold osmotic shock. the protein is dimeric, has an apparent molecular weight of 28 000 and an isoelectric point of 6.1. sodium ions were required for optimum substrate binding, however, the divalent cations zn2+, mg2+, and co2+ were inhibitory. the c protein was relatively stable but sensitive to various detergents and chaotropic agents. ap ...	1979	383235
tryptophan-requiring parental strains yield salmonella typhimurium x escherichia coli hybrid recombinants with functional tryptophan operons.	crosses between an escherichia coli hfr trp strain and three salmonella typhimurium f- trp strains produced some trp+ hybrids in which the tryptophan operon is composed of genes from both parental species.	1979	383245
mutagenicity of soot and associated polycyclic aromatic hydrocarbons to salmonella typhimurium.		1979	383281
chemical characterization of 465 known or suspected carcinogens and their correlation with mutagenic activity in the salmonella typhimurium system.	since chemicals exhibiting mutagenic activity pose a potential hazard to their users, there is increasing acceptance of mutagenicity testing as an integral part of a premarketing toxicological evaluation of chemicals. in vitro testing has gained much notoriety as quick and relatively inexpensive means to assess the mutagenic potential of chemicals. however, the innovative use of microsomes to simulate metabolism has not changed the fact that in vitro activation cannot duplicate faithfully the me ...	1979	383284
mutagenicity of the naturally occurring carcinogen cycasin and synthetic methylazoxymethanol conjugates in salmonella typhimurium.	the aglycone methylazoxymethanol of the naturally occurring carcinogenic glucoside, cycasin, has previously been shown to be mutagenic, but cycasin per se has not. in this work, cycasin was demonstrated to be mutagenic using a modification of the ames salmonella test in which it was preincubated with beta-glucosidase and the tester strain in liquid medium. the mutagenicity of cycasin to six histine-depedent salmonella strains varied considerably with strain hisg46 being the most susceptible. met ...	1979	383289
[do pigeons play a part in human infections with salmonella typhimurium var. copenhagen (author's transl)].		1979	383458
a morphological study in germfree mice (salmonella infection).	the morphological manifestation of the intestinal infections of salmonella typhimurium by the intestine rolled method in both conventional dki and germfree mice have been investigated in our laboratory. in the conventional mice, the morphological manifestation of intestinal infection shows no difference from the general features of infection, while in the germfree mice, the manifestation is characterized by the so-called non-reactive necrotizing enteritis without cellular reaction. when infectio ...	1979	383491
his-linked hydrogen sulfide locus of salmonella typhimurium and its expression in escherichia coli.	a his-linked h2s locus of salmonella typhimurium has been further defined by direct isolation of h2s mutants. expression of this locus in escherichia coli has been demonstrated.	1979	383686
the ends of tn10 are not is3.	by heteroduplex and hybridization analysis we showed that the inverted repetition (here called is10) at the ends of the translocatable tetracycline resistance element tn10 is not is3, as had previously been reported by ptashne and cohen (j. bacteriol. 122:776--781, 1975). further analysis confirmed the homology between is3 and the alpha beta sequence of f and demonstrated that is10 was not present in the genomes of salmonella typhimurium lt2 or escherichia coli k-12.	1979	383689
ribosomal ribonucleic acid isolated from salmonella typhimurium: absence of the intact 23s species.	ribonucleic acid (rna) isolated by four distinct methods and from a variety of salmonella typhimurium strains lacked intact 23s ribosomal rna (rrna). on sucrose gradients which minimize aggregation, the vast majority of s. typhimurium rrna sedimented as a 16s peak with a 14s shoulder. rna from this region of the gradient was resolved into three discrete bands by electrophoresis in formamide. two very minor s. typhimurium rna peaks were resolved at 21s and 10s on sucrose gradients, and each peak ...	1979	383696
two mutations which affect the barrier function of the escherichia coli k-12 outer membrane.	two genetically distinct classes of novobiocin-supersensitive mutants were isolated from escherichia coli k-12. one class, given the phenotypic name nbsa, lies at 10 min on the e. coli chromosome. the order of the genes in this region, based on transductional analyses, is proc nbsa plsa pure. the second, nbsb, lies at 80 min. the order of the genes in this region, based on transduction analyses, is xyl cyse nbsb pyre. both classes of mutants show increased sensitivity to hydrophobic drugs but ar ...	1979	383699
mutation spot of escherichia coli increases expression of the histidine operon deleted for the attenuator.	f'-episomes carrying the salmonella typhimurium wild-type or attenuator-deleted histidine (his) operons were introduced into escherichia coli strains containing rela or spot single and double mutations known to affect guanosine 3'-diphosphate 5'-diphosphate (ppgpp) and guanosine 3'-triphosphate 5'-diphosphate (pppgpp) levels. expression of the his operon and expression of the gene for 6-phosphogluconate dehydrogenase (gnd) were measured during balanced growth in amino acid-rich and minimal media ...	1979	383702