| [lipid composition of escherichia coli cells sensitive and resistant to tetracycline]. | the following variants of e. coli resistant to tetracycline have been obtained from a strain of e. coli w-677 susceptible to 2.5 mcg/ml of the antibiotic: ri, a recombinant resulting from crossing e. coli w-677 (recipient) and e. coli csh-222 (donor), resistant to 200 mcg/ml of tetracycline; r2, a strain isolated upon numeros passaging e. coli w-677 on media containing the antibiotic, resistant to 25 mcg/ml of tetracycline. the ability of the resistant variants to bind the antibiotic decreased, ... | 1977 | 329066 |
| [influence of glucose on transport of phenylacetic acid and synthesis of penicillin amidohydrolase in escherichia coli]. | | 1977 | 329068 |
| genetic analysis of mutations affecting ribonuclease ii in escherichia coli. | exonuclease activity in an escherichia coli k12 mutant s296 is less than 1% of that in the wild type strain (nikolaev et al., 1976). another mutant n464 has thermolabile ribonuclease ii (castles and singer, 1968; kuwano et al., 1969). genetic analysis of these mutants by hfr conjugation and p1 transduction indicates that the structural gene (rnb) for ribonuclease ii is located near the pyrf gene (28 min on the e. coli genetic map of bachmann, low and taylor (1976)), and the most probable gene or ... | 1977 | 329098 |
| host-dependent modification of bacteriophage t7 and samase-negative t3 derivatives affecting their adsorption ability. | when passaging phage t7 and samase-negative t3 mutants between e. coli strains with identical (ecob) or without (ecoo) dna host specificity, phenotypically a host-controlled modification and restriction is observed. this phenomenon is not due to "classical" modification and restriction of the bacteriophage dna but depends on the reversibly altered adsorption capacity of the phages on the different host strains. | 1977 | 329099 |
| dependence of dna dark repair on protein synthesis in escherichia coli. | we investigated the influence of amino-acidless treatments applied prior and after uv irradiation (aa-irradiated aa+; aa-irradiated a-; aa+ irradiated aa-) on survival, dimer excision, postirradiation dna degradation, dna synthesis and sedimentation profiles of parental dna of e. coli b/r hcr+ cells. in dependence on the treatment applied, the fluence 50 j/m2 yielded distinctly different fractions of survivors within 0,03-85%. in all cases dimers were completely excised. the rate of dna degradat ... | 1977 | 329100 |
| host factor for coliphage q beta rna replication: presence in procaryotes and association with the 30s ribosomal subunit in escherichia coli. | the host factor required for in vitro coliphage q beta rna replication, a heat-stable rna binding protein present in uninfected escherichia coli, has been detected by both immunological and functional tests in acinetobacter calcoaceticus, klebsiella pneumoniae, pseudomonas aeruginosa and pseudomonas putida. it was not detectable by these criteria in bacillus stearothermophilus, bacillus subtilis, caulobacter crescentus, micrococcus lysodeikticus, rhodopseudomonas capsulata or saccharomyces cerev ... | 1977 | 329101 |
| trans-dominance of dnaa mutants in escherichia coli. | temperature sensitivity of growth and dna synthesis was tested in merogenotes heterozygous for the dnaa allele. all combinations tested (f dnaa+/dnaa5, f dnaa+/dnaa46, f dnaa+/dnaa204, f dnaa5/dnaa+, f dnaa204/dnaa+) were temperature sensitive. the mutant dnaa allele is thus trans-dominant to the wild type allele. | 1977 | 329102 |
| transcription of insertion elements is1 and is2 in vitro. | insertion elements is1 and is2 integrated within the gal operator-promoter region, an is1 element in gene galt and insertions is1 and is2 integrated in the xyciiop region of phage lambda were transcribed in vitro with e. coli rna-polymerase. the insertion elements are transcribed exclusively by polymerase molecules started at the gal promoter and the lambdapr promoter respectively. no promoter exists on is1 or is2 which can be recognized by rna-polymerase in the pure in vitro transcription syste ... | 1977 | 329104 |
| the effect of the ribosomal protein s1 from escherichia coli on the synthesis in vitro of bacterial-, dna phage- and rna phage proteins. | using an in vitro preparation for protein synthesis, we have studied the effect of the ribosomal protein s1 from escherichia coli on the synthesis of the coat protein of the rna-containing phages qbeta and ms2, on that of an "early" and a "late" enzyme encoded by the dna containing phage t7, and on that of anthranilate synthetase, an enzyme encoded by the bacterial tryptophan operon. our results indicate that for the synthesis of these five proteins the presence of s1 is required. from these res ... | 1977 | 329105 |
| bacteria with defective rho factors suppress the effects of n mutations in bacteriophage lambda. | a prediction based on the model for n-gene function of bacteriophage lambda proposed by roberts (1971) is confirmed by showing that a lambdan- double mutant is able to grow in strains of e. coli with defective rho transcription termination factors. the burst sizes for lambdan- in these strains range from 5 to 24% the burst sizes for lambdan+ in the same strain. this low level of suppression is also evident in the levels of synthesis of the lambda exonuclease and is consistent with other evidence ... | 1977 | 329106 |
| a conditional antimutator in e. coli. | a pleiotropic mutation in the purb gene of e. coli is described which lowers the spontaneous mutation frequency of other genes. the antimutator effect is very large for some genetic loci, but is absent at other sites. both forward and reverse mutations are affected. this mutation in purb is temperature sensitive for both adenine auxotrophy and the antimutator action. adenine, or adenosine, or low temperature growth abolish the antimutator effect. the mutagenicity of base analogs and nitrosoguani ... | 1977 | 329107 |
| active protection by bacteriophages t3 and t7 against e. coli b- and k-specific restriction of their dna. | the bacteriophages t3 and t7 are not modified and restricted by e. coli strains with different host specificity (e. coli b, k, o) in vivo. the phages code for a gene product with the ability to overcome classical restriction (ocr): ocr- mutants are subject to modification and restriction via dna methylation vs cleavage. the t3 genome possesses recognition sites for the restriction endonuclease r.ecob which, unless the dna is b-specifically modified, trigger 5-7 dna cleavages. the ocr gene functi ... | 1977 | 329108 |
| a new ribosomal protein locus in escherichia coli: the gene for protein s6 maps at 97 min. | a mutant of e. coli selected for temperature-sensitive growth on rich medium harbored an altered ribosomal protein s6 (isono et al., 1976). this mutant was found to possess at least two mutations, one being responsible for the temperature-sensitivity and the other for the s6 alteration. crosses with various hfr strains as well as transductions with p 1kc revealed that the former mutation mapped at 98 min and the latter at 97 min. furthermore, rec a derivatives of this mutant heteromerodiploid f ... | 1977 | 329109 |
| functional inactivation rates of the messenger rna molecules coding for the individual ribosomal proteins in escherichia coli. | | 1977 | 329110 |
| repression of inducible enzyme synthesis in a mutant of escherichia coli k 12 deleted for the ptsh gene. | the genome of lambda phage with thermosensitive repressor was inserted into the pts region of the escherichia coli chromosome. this lysogenic culture possessed the pts1 phenotype at 30 degrees c. a mutant strain with a deletion covering the ptsh gene was isolated after a prophage curing procedure. the deletion nature of the pts mutation was confirmed in genetical and biochemical experiments. the deletion covered a small fragment of the bacterial genome not extending in the ptsi and lig genes. th ... | 1977 | 329116 |
| a new ribosomal mutation which affects the two ribosomal subunits in escherichia coli. | a new ribosomal mutant resistant to erythromycin is described. the product of the gene eryc seems to be implicated in the assembly of the two ribosomal subunits, particularly in the maturation process of the rna 23s and 16s. | 1977 | 329117 |
| polyamines and protein synthesis: studies in various polyamine-requiring mutants of escherichia coli. | different escherichia coli mutants auxotrophic for polyamines were studied in order to investigate the relationships among polypeptide synthesis in cell-free systems, ribosomal distribution profiles and endogenous polyamine pools. the in vitro protein synthetic activity and the polyribosomal content were reduced in extracts from putrescine-starved cells of the double mutans ma 255 and ma 261, but not in the arginine-conditional auxotroph dk 6. putrescine addition to the cultures of all these str ... | 1977 | 329122 |
| escherichia coli serotypes and diarrhea. | | 1977 | 329137 |
| self-assembly and catalytic activity of the pyruvate dehydrogenase multienzyme complex of escherichia coli. | | 1977 | 329143 |
| [escherichia coli o 83 infection in the mother causing sepsis in the newborn infant]. | | 1977 | 329177 |
| recent developments in diarrheal diseases. | diarrheal diseases result from two different processes: toxin elaboration by pathogens such as vibrio cholerae and some strains of escherichia coli and invasion of tissue, eg, by shigellae and salmonellae. intestinal motility serves as a normal cleansing mechanism of the intestine, and drugs that decrease this motility may facilitate replication of pathogens and their attachment to or invasion of the intestinal tissue. therapy should not be aimed at suppressing the symptom of diarrhea. it is now ... | 1977 | 329247 |
| use of polylysine for adsorption of nuclei acids and enzymes to electron microscope specimen films. | enzymes and nucleic acids, both free and as bound in binary complexes, adsorb to electron microscope specimen films in well-distributed fashion if a dilute solution of polylysine is previously applied to the films. electron micrographs are exhibited that demonstrate the usefulness of the technique in visualizing double- and single-stranded dna, escherichia coli rna polymerase (nucleosidetriphosphate:rna nucleotidyltransferase, ec 2.7.7.6) in negative stain, and polymerase complexed to poly(da-dt ... | 1977 | 329278 |
| shape of the 50s subunit of escherichia coli ribosomes. | extrapolation of a series of low-angle neutron scattering curves to infinitely high contrast gives a scattering function ic(kappa) which is dependent on the shape of the solute molecule. for the 50s subunit of e. coli ribosomes, the first part of the structure determination by neutron scattering, namely the determination of the molecular shape from ic(kappa), is reported. the result is in good agreement with models of the 50s subunit determined by electron microscopy. | 1977 | 329279 |
| photoreactivation of conversion and de novo suppressor mutation in escherichia coli. | | 1977 | 329297 |
| [sensitivity and repair of the dna-membrane complexes of e. coli and b/r e. coli b/s-1 bacteria irradiated with gamma-quanta]. | | 1977 | 329336 |
| [processing of trna precursors in escherichia coli (author's transl)]. | | 1977 | 329356 |
| antigenic characteristics of some e. coli membrane proteins. | | 1977 | 329378 |
| water-to-air transfer of virus. | bubbles rising through suspensions of the bacteriophages t2 and t4 and of escherichia coli adsorb and eject these particles in droplets that are formed when the bubbles burst. the concentration of the viruses in ejected droplets, determined from electron microscopy, exceeded the suspension concentration by 50 times. similar results were obtained for escherichia coli. the viability of some of the adsorbed particles was established by biological counts. | 1977 | 329413 |
| antibiotic agranulocytosis: association with cephalothin and carbenicillin. | a 65-year-old woman developed agranulocytosis on two separate occasions following prophylactic administration of antibiotics before cardiac surgery. in the first leukopenic episode, large doses of cephalosporin derivatives were the only drugs implicated, and in the second, carbenicillin was believed responsible. life-threatening septicemia occurred with pseduomonas aeruginosa and later with escherichia coli. erythrocytes, platelets, and lymphocytes were not affected during these granulocytopenia ... | 1977 | 329421 |
| intrarenal mycotic aneurysm. | a case is presented of a sixty-seven-year-old man in whom escherichia coli septicemia developed after catheterization, followed by left renal hemorrhage due to an intrarenal mycotic aneurysm. because of clinical circumstances that prevailed, treatment was nonsurgical consisting of multiple blood transfusions and intravenous antibiotics. the aneurysm healed spontaneously as proved by subsequent renal arteriography. | 1977 | 329523 |
| growth of bacteriophage p1 in recombination-deficient hosts of escherichia coli. | | 1977 | 329556 |
| the effects of cobra venom factor, an inhibitor of the complement system, on the sequence of morphological events in the rat kidney in experimental pyelonephritis. | | 1977 | 329591 |
| cell growth and metabolic products of escherichia coli in nitrate respiration. | | 1977 | 329593 |
| r-factor-mediated antibiotic resistance in e. coli strains isolated from piglets in sweden. | e. coli strains, isolated from piglets over the periods 1964-1968 and 1974-1975, were investigated and compared with respect to antibiotic resistance. the frequency of monoresistant strains decreased from 50% in 1964-68 to 27% in 1974-75, while that of strains showing double or multiple resistance increased from 13% to 22%. the proportions of the different resistance determinants were as follows (figures for 1964-68 within parentheses): tetracycline 23% (49%), sulphaisodimidine 38% (24%), strept ... | 1977 | 329617 |
| immunosuppression mediated by adult worms in chronic schistosomiasis mansoni. | a marked reduction in the number of plaque-forming cells from spleens of mice infected with schistosoma mansoni to sheep erythrocytes (srbc) and lipopolysaccharide from escherichia coli was observed. this reduction coincided with the late stages of the infection and was also observed in unisexual infection with male worms. treatment of the animals with a schistosomicidal compound (oxamniquine) almost completely abolished the immunosuppression. the suppression could be induced by administration o ... | 1977 | 329699 |
| a new affinity column for the purification of thymidine kinase from escherichia coli. | | 1977 | 329709 |
| [electron microscopic study of the combined action of ampicillin and cephalexin on e. coli]. | the data of electron microscopy study of morphological variation of e. coli, strain 423 in the logarithmic phase after exposure to ampicillin (2 gamma/ml) and cephalexin (4 gamma/ml) are presented. pronounced ultrastructural changes not only in the cell wall but also in the cytoplasm were found. after exposure to ampicillin alone changes of the same type were observed. however, after exposure to the combination of the 2 antibiotics these changes were more pronounced and observed in the predomina ... | 1977 | 329750 |
| [effectiveness of gentamicin sulfate in suppurative-inflammatory processes of varying localization]. | antibiotic sensitivity of 486 strains of grampositive and gramnegative organisms isolated from patients with purulent infections was studied in vitro. gentamicin was shown to be highly active as compared to kanamycin and other antibiotics against the main causative agents of purulent inflammatory infections including multiresistant e. coli, proteus, ps. aeruginosa, staphylococcus. high efficiency of gentamicin in therapy of peritonitis, septic conditions, purulent postoperative wounds, infection ... | 1977 | 329751 |
| ozone-induced dna degradation in different dna polymerase i mutants of escherichia coli k12. | | 1977 | 329840 |
| gene expression in stringent and relaxed strains of escherichia coli during amino acid deprivation. | | 1977 | 329843 |
| commentary: escherichia coli enterotoxin. | | 1977 | 329844 |
| regulation of membrane lipid synthesis in escherichia coli after shifts in temperature. | | 1977 | 329861 |
| thermodynamic studies of the reversible association of escherichia coli ribosomal subunits. | the kinetics of association of escherichia coli 30s and 50s ribosomal subunits have been carried out as a function of temperature after a magnesium jump from 1.5 to 3 mm. turbidimetric recordings combined with a stopped-flow apparatus were used to follow the kinetics. the data show that the rates of formation and dissociation of the 70s particles at 3 mm mg2+ and +25 degrees c were, respectively: k2 = 10(5) m-1 s-1, k1 = 4,5 x 10(-3) s-1; lowering the temperature decreases the rate constants wit ... | 1977 | 329865 |
| kinetic and photochemical studies and alteration of ultraviolet sensitivity of escherichia coli thymidine kinase by halogenated allosteric regulators and substrate analogues. | | 1977 | 329868 |
| subunit topography of rna polymerase from escherichia coli. a cross-linking study with bifunctional reagents. | the quaternary structures of escherichia coli dna-dependent rna polymerase holenzyme (alpha 2 beta beta' sigma) and core enzyme (alpha 2 beta beta') have been investigated by chemical cross-linking with a cleavable bifunctional reagent, methyl 4-mercaptobutyrimidate, and noncleavable reagents, dimethyl suberimidate and n,n'-(1,4-phenylene)bismaleimide. a model of the subunit organization deduced from cross-linked subunit neighbors identified by dodecyl sulfate-polyacrylamide gel electrophoresis ... | 1977 | 329870 |
| ficellomycin and feldamycin; inhibitors of bacterial semiconservative dna replication. | the two peptide-like antibiotics ficellomycin and feldamycin impair semiconservative dna replication but not dna repair synthesis in bacteria. specifically both antibiotics cause the accumulation of a 34s dna species in toluenized escherichia coli cells which lacks the capability of being integrated into larger dna pieces and eventually the complete bacterial chromosome. novobiocin, a known inhibitor of replicative dna synthesis, was investigated for comparative purposes. the action of this latt ... | 1977 | 329871 |
| in vitro biosynthesis of functional escherichia coli su3+ tyrosine transfer rna. | | 1977 | 329874 |
| incorporation of phosphorothioate groups into fd and phi x174 dna. | we have synthesized fd and phi x174dna in the presence of 2'-deoxyadenosine 5'-o-(1-thiotriphosphate) (datp alpha s) and the corresponding phosphorothioate derivatives of dctp and dttp using ether-permeabilized e. coli cells or crude cell extracts of e. coli dna polymerase i. reaction rates of enzymes involved in the formation or breakdown of dna are decreased in the presence of phosphorothioates. the amount of label incorporated with [35s]datp alpha s suggests that the damp has been completely ... | 1977 | 329875 |
| transient breakdown of the permeability barrier of the membrane of escherichia coli upon hypoosmotic shock. | | 1977 | 329877 |
| discrimination between rb+ and k+ by escherichia coli. | 1. the k+ requirment of escherichia coli is only partially fulfilled by rb+. the molar growth yield on rb+ was about 5% of that on k+ and the growth rate in rb+-supplemented media is lower thatn in k+ influx by any of the four k+ transport systems of e. coli. the high-affinity kdp system (km = 2 micron) is poorly traced by 86rb+. it discriminates against a 86rb+ tracer at least 1000-fold. the two moderate affinity systems, the high-rate trka system (km = 1.5 mm) and the moderate rate trkd system ... | 1977 | 329878 |
| interrelationship of the phage lambda receptor protein and maltose transport in mutants of escherichia coli k12. | | 1977 | 329879 |
| translation in escherichia coli mini-cells containing hamster mitochondrial dna-co1e1 - ampr recombinant plasmids. | hamster mitochondrial dna is cleaved into two fragments (4.2 and 11.4 kilobase pairs of dna (kb)) by the restriction enzyme, eco ri. recombinant dna molecules formed in vitro between an escherichia coli plasmid, co1e1 - ampr, and eco ri-digested hamster mitochondrial dna were transformed into e. coli k12. the translation products of the parent plasmid, co1e1 - ampr, and recombinant plasmid dnas containing (i) the 4.2 kb mitochondrial dna fragment and (ii) the 11.4 kb fragment were characterized ... | 1977 | 329883 |
| lutropin stimulation of rna synthesis in corpus luteum chromatin. | lutropin and human choriogonadotropin stimulated the endogenous chromatin-associated polymerase activity in purified chromatin prepared from nuclei of bovine corpus luteum. chromatin was incubated in two different buffer systems: one that mainly supports the activity of polymerase i, another that supports the activity of polymerase ii and is largely alpha-amanitin sensitive. the hormones lutropin and chorigonadotropin stimulated an increase in the rate of incorporation of [14c]atp or [14c]utp in ... | 1977 | 329886 |
| expression of a bacterial gene for guanine synthesis inserted into colicin e1 factor by an in vitro recombination. | regulation of expression of a bacterial guaa gene inserted into colicin e1 dna by an in vitro recombination was studied under various growth conditions. in escherichia coli k-12 cells that carried this hybrid colel plasmid the level of guaa enzyme activity was not regulated by the concentration of guanine in the medium, but by the number of plasmid dna copies. the optimal conditions for amplifying the guaa gene product by chloramphenicol treatment were determined. the level of guaa enzyme activi ... | 1977 | 329887 |
| modification of tyrosine residues of the lactose repressor protein. | reaction of the lactose repressor protein from escherichia coli with high molar excesses (up to 800 fold) of tetranitromethane resulted in modification of tyrosine residues in the amino-terminal and core regions of the molecule. tyrosines 7 and 17 exhibit significant reactivity at low levels (5-10 fold molar excess) of tetranitromethane. the loss of operator binding activity upon nitration at these low concentrations of reagent indicates involvement of these two tyrosines in the binding process. ... | 1977 | 329889 |
| histidinol dehydrogenase from salmonella typhimurium and escherichia coli. purification, some characteristics and the amino acid sequence around a reactive thiol group. | the purification and some physical properties of histidinol dehydrogenase, l-histidinol-nicotinamide adenine dinucleotide oxido-reductase (ec 1.1.1.23) from either salmonella typhimurium or escherichia coli are reported in this paper. modification of histidinol dehydrogenase with one equivalent of n-(4-dimethylamino-3,5-dinitrophenyl)maleimide at ph 6.8 yields an enzyme that is inactive toward the oxidation of l-histidinol. the modified cysteine residue was located in an acid insoluble tryptic c ... | 1977 | 329890 |
| [on the role of n7 atoms of guanosine in trna-phe (e. coli) in interaction with ribosomes]. | the influence of alkylation of phe-trnaphe (e. coli) with 2',3'-o-[4-(n-2-chloroethyl-n-methylamino)-benzylidene]-uridine - 5' - methylphosphate on its ability to participate in non-enzymatic complex formation with ribosomes and poly-u was investigated. phe-trnasphe, containing alkylated guanosines at different positions, including anticodone, are active in binding with ribosomes. it is concluded, that n7 nitrogens of guanosine of the trhaphe are not elements, significant for the interaction wit ... | 1977 | 329897 |
| [some peculiarities of phage ddvi-specific methylases]. | the types of methylases are found in the cellular extract of escherichia coli b, infected with phage ddvi. one of them is a cellular enzyme, which methylates adenine to form 6-methylaminopurine (6-map) and is repressed in the infected cell in vivo. the second type, which is not found in the non-infected cells, is specific for phage ddvi and induces the formation of 7-methylguanine (7-mg). both enzymes recognize various sites, which accounts for the ratio 6-map/7-mg to vary in heterological dnas ... | 1977 | 329898 |
| [t2 dna, modified by 2,2,6,6-tetramethyl-4-bromoacetooxypiperidine-i-oxyl as a template for rna polymerase from e. coli b]. | t2-dna was modified by 2,2,6,6-tetramethyl-4-bromoacetooxypiperidine-1-oxyl (i) at different nacl concentrations (10(-1) m nacl--10(-4) m nacl). modified dna were investigated as templates for the rna-polymerase from e. coli b. it was shown that t2-dna modified i in 0,1 m nacl completely preserves the native secondary structure, has a low degree modification (1 molecule i per 1000-2000 nucleotide pairs), but is a noneffective template for the rna-polymerase from e. coli b (20%-40% as compared wi ... | 1977 | 329900 |
| microbiological relevance and clinical potential of ampicillin-cloxacillin synergism. | recent demonstration "in vitro" that combinations of ampicillin and cloxacillin, using concentrations at which neither were previously effective, will kill certain resistant gram negative bacteria, has important clinical potential. we therefore studied 50 ampicillin resistant gram negative rods cultured from septicemic patients for synergism. 7 of 23 e. coli strains with a minimal bactericidal concentration (mbc) of 128 microgram/ml were killed by combinations containing 4-32 microgram/ml ampici ... | 1977 | 329905 |
| [test-strains of e. coli for detection of chemical mutagens]. | two temperature-sensitive mutants--ap 16 and ap 18 were isolated after the treatment of e. coli ab2500 strain with two mutagens (acridine orange and 5-bromuracil). the mutants obtained proved to be sensitive and formed revertants when treated with the following agents: n-methyl-n'-nitro-n-nitrosoguanidine, hydroxylamine, nitrous acid, sodium metabisulfite, methylmethansulfonate, and proflavine. introduction into the mentioned strains of additional mutation causing elevation of their sensitivity ... | 1977 | 329914 |
| [cytopathogenic effect of e. coli cells containing heterogeneous human o(h) type antigen on human cells in culture]. | interaction of two enteropathogenic strains e. coli o55-k59 and human hela cells containing o(h) isoantigen was studied. when e. coli strain no. 5789 containing heterologic antigen o(h) was added to hela cell culture the cytopathogenic effect with the microbial doses of 2 x 10(10), 2 x 10(5), 2x 10(4) was revealed on the third day of the interaction. a dose of 2 x 10(3) of e. coli microbes gave no such effect. strain no. 3827 containing no heterologic antigen of abo type failed to exert any cyto ... | 1977 | 329916 |
| anaphylactic reactions to endotoxin in guinea-pig tissues: relationship to endotoxin toxicity. | 1 a lipopolysaccharide extract of escherichia coli 026:b6 cells (026:b6(b) endotoxin) was shown to be toxic to normal adult guinea-pigs. 2 the agent had no action on isolated preparations of ileum and heart taken from normal adult guinea-pigs. 3 ileal segments from animals actively immunized against 026:b6(b) endotoxin showed dose-dependent contractions when exposed to endotoxin. desensitization phenomena were demonstrated. 4 reactivity of 026:b6(b) endotoxin was transferred to isolated preparat ... | 1977 | 329934 |
| feline endotoxin shock: effects of methylprednisolone on kininogen-depletion, on the pulmonary circulation and on survival. | 1 escherichia coli endotoxin, administered intravenously in a dose of 2 mg/kg to pentobarbitone anaesthetized, artificially ventilated cats resulted in pulmonary hypertension, systemic hypotension and an immediate (1-2 min) 30-40% reduction in plasma kininogen, an effect which probably indicates a release of plasma kinins. 2 methylprednisolone (30 mg/kg), when administered 30 min before endotoxin, did not influence the endotoxin-induced pulmonary hypertension or systemic hypotension but complete ... | 1977 | 329935 |
| reduced synthesis of beta-galactosidase in escherichia coli infected with phage phi x 174. | the synthesis of beta-galactosidase (ec 3.2.1.23;beta-d-galactoside galactohydrolase) in e. coli was repressed as a result of infection with single-stranded dna phage phi chi 174. evidence is presented to show that this repression was not due to the restricted entry of the inducer molecules into the infected cells but to some phage-specified product(s). it was further shown that either the infected cells synthesized a fewer number of enzyme-specific mrna or all such molecules were translated wit ... | 1977 | 329962 |
| structural proteins of a lipid-containing bacteriophage which replicates in escherichia coli: phage pr4. | pr4 is a lipid-containing bacteriophage which is able to replicate in escherichia coli. the virus was labeled with either [14c]leucine and [14c]threonine or h235so4 and then purified by several rounds of sucrose gradient centrifugation. autoradiographs showed the virus to be composed of six major protein species with molecular weights (1) 68 000, (2) 47 500, (3) 38 500, (4) 35 000, (5) 20 700, (6) 16 500 daltons. electropherograms showed protein no. 2 to be the major protein, comprising about 43 ... | 1977 | 329963 |
| spacer transfer rnas in ribosomal rna transcripts of e. coli: processing of 30s ribosomal rna in vitro. | at least three different transfer rnas are produced by in vitro processing of 30s ribosomal rna which accumulates in rnaase iii- strains of e. coli. two of these trnas, trnaglu2 and trnaile1, have previously been shown to be "spacer trnas"--that is, genes for their synthesis are located in rrna transcription units between the cistrons for 16s and 23s rrnas (lund et al., 1976). the third trna whose sequences are contained in 30s rrna is trnaala1b. in addition to the trnas, 5s rrna and several oth ... | 1977 | 329997 |
| expression of spacer trna genes in ribosomal rna transcription units carried by hybrid col e1 plasmids in e. coli. | | 1977 | 329999 |
| effects of pyrrol-carboxylic acid derivatives on the growth of coliphages. | effects of 14 pyrrol-carboxylic acid derivatives and analogues (py-compounds) on the growth of coliphage ms2 using e. coli e102 (hfr) as the host were measured by the agar double-layer method. enlargements of plaque size were observed with 7 py-compounds but increase in plaque numbers was not induced. these enlargements of plaque size were specific to rna coliphages ms2, ga and qbeta and not found with dna coliphages delta ac and t4. furthermore, the interaction between py-compound py-10 and the ... | 1977 | 330014 |
| transfer of episome f'lac+ and chromosomal trp+ genes from erwinia amylovora to salmonella typhimurium. | the f'lac+ episome of escherichia coli origin was transferred by conjugation with frequencies of 10(-7) to 10(-5) from erwinia amylovora to 14 out of 15 salmonella typhimurium trp female parents. the chromosomal trp+ genes were transferred with frequencies of 10(-7) to 10(-6) only to one trpb and 2 trpd female parents, which have a point mutation in the 2nd and fourth structural genes, respectively, of the tryptophan operon. the transferred male trp+ genes became integrated at the selected sites ... | 1977 | 330120 |
| [study of gastric secretion in white rats with a chronic gastric fistula on endotoxin exposure]. | the author carried out a study on the stomach secretion in white rats endotoxin shock, induced by venous adminsitration of endotoxin, obtained from escherichia coli. stomach fistula was made on the rats in advance and the stomach juice was collected under the condition of chronic experiment. the amount of stomach juice was estimated in mililiter per hour as well as the content of free hydrochloric acid, total aidity and electrophoresis of proteolytic enzymes. there was a statistically significna ... | 1977 | 330148 |
| studies of the topography of the binding site of dna-dependent rna polymerase from escherichia coli for the antibiotic rifamycin sv. | | 1977 | 330165 |
| limited proteolysis of elongation factor tu from escherichia coli, multiple intermediates. | limited proteolysis of native elongation factor tu (mr 44 000) by trypsin occurs in at least three distinct steps. the first intermediate arises through cleavage at a site about 65 residues from the amino-terminal end of the protein. it is functionally active [jacobson, g. r. & rosenbusch, j. p. (1976) biochemistry, 15, 5105-5110] and is partially protected from further degradation by the antibiotic kirromycin. the second step converts this intermediate to one of similar size (mr 37 000) which n ... | 1977 | 330167 |
| transcription spectra in e. coli growing rapidly or slowly. | | 1977 | 330198 |
| correlation between the susceptibility of e. coli to phagocytosis and their ability to invade hela cells in vitro. | the susceptibility of several strains of e. coli to phagocytic killing by polymorphonuclear lencocytes and the ability of the same strains to invade hela cells were studied. it was found that only the strains resistant to killing by leucocytes were able to penetrate and multiply within hela cells. | 1977 | 330203 |
| breakdown of ppgpp in spot and spot-cells of escherichia coli. manganese and energy requirement and tetracycline inhibition. | | 1977 | 330223 |
| the number of rrna genes in escherichia coli. | | 1977 | 330226 |
| hydrodynamic studies on the escherichia coli robosomal proteins s8 and l6, prepared by two different methods. | | 1977 | 330229 |
| separation of two forms of if-3 in escherichia coli by two-dimensional gel electrophoresis. | | 1977 | 330232 |
| the primary structure of the initiation factor if-3 from escherichia coli. | | 1977 | 330233 |
| participation of cytochrome b to the in-vitro reconstitution of the membrane-bound formate-nitrate reductase of escherichia coli k 12 and the possible role of sulfhydryl groups and temperature in the reconstitution process. | | 1977 | 330235 |
| mutants of escherichia coli which lack a component of penicillin-binding protein 1 are viable. | | 1977 | 330236 |
| small-angle x-ray scattering study of s4-rna, the 16 s rna binding site for the protein s4 from escherichia coli ribosomes. | | 1977 | 330240 |
| tyrosine fluorescence of s8 and s15 escherichia coli ribosomal proteins. | | 1977 | 330244 |
| recognition of rna by ribosomal protein s1: interaction of s1 with 23 s rrna of escherichia coli. | | 1977 | 330245 |
| a comparison of the amino-terminal sequences of several carbohydrate binding proteins from escherichia coli and salmonella typhimurium. | | 1977 | 330247 |
| symptomatic treatment of diarrhea with bismuth subsalicylate among students attending a mexican university. | students attending a mexican university who developed diarrhea were randomly treated with bismuth subsalicylate or a placebo. one hundred and eleven were given 30 ml each 1/2 hr until eight doses (total dose of active drug 4.2 g) were given and 58 students received twice this dose (8.2 g of active drug) over the 3 1/2-hr treatment period. the number of unformed stools was significantly decreased in both bismuth subsalicylate treatment groups compared to the placebo controls for the period 4 to 2 ... | 1977 | 330307 |
| [identification of 3 genes in the f-plasmid of escherichia coli k-12]. | the f'argg plasmid and its two transfer-deficient (tra-) analogues have been used to analyse the pleiotropic effect of a mutation in the integrated f-factor of hfrc strain. this mutation has been shown to disturb the functioning of at least three plasmid genes constituting, probably, a single regulon: the rsf gene determining the production of recombination-stimulating factor via conjugation (rsf); the prt gene responsible for the protective effect of the plasmid against n-methyl-n'-nitro-n-nitr ... | 1977 | 330313 |
| [mutation of bacteriophage t4 restoring phage supressor psul+ activity in bacterial strain escherichia coli bn]. | the mutant of bacteriophage t4psu1+xf2 carrying a mutational aleration in the central region of proline-serine trna precursor is isolated. the mutational alteration results in the recovery of amber suppressor activity of phage psu1+ serine trna in escherichia coli bn in which the synthesis of this trna is normally blocked. since the amber suppressor activity of mutant serine trna becomes sensitive to a restrictive action of strr mutations, its structure seems to be different from that of parenta ... | 1977 | 330314 |
| [isolation and properties of merodiploid strains with f-factor including the pts-region of the escherichia coli k-12 chromosome]. | a technique of hybridization of haploid methanol-utilizing yeast pichia pinus mh4 is worked out using uv- and n-nitrosoguanidine-induced auxotrophic mutants. vegetative diploid cultures are isolated. tetrad analysis and random spore analysis have revealed a meiotic nature of spores, recombination of genetic material in the process of sporulation and the chromosomal nature of some mutations. a possibility to construct a genetic map of the yeast pichia pinus mh4 is demonstrated on the basis of tet ... | 1977 | 330316 |
| [is-elements and their role in genetic recombination]. | the data concerning the biological functions and properties of short specific polynucleotide sequences (so called insertion sequences--is) are reviewed. is elements integrated in a genome can lead to strongly polar mutations in escherichia coli, its bacteriophages and plasmids, while some is (is2) being integrated in inverted orientation turn on the gene activity. several copies of the is elements are present in the e. coli chromosome. a characteristic feature of is is their ability to reca-inde ... | 1977 | 330320 |
| simultaneous and successive induction of synthesis of beta-galactosidase and tryptophanase in escherichia coli k 12 in the chemostat. | beta-galactosidase and tryptophanase were induced either simultaneously or successively during continuous cultivation of the inducible strain escherichia coli k 12 in the chemostat. growth was limited by glycerol and the dilution rate was 0.1 h-1. during both the simultaneous and successive induction specific rates of synthesis, as well as maximum enzyme levels, were identical with those obtained after independent induction of individual enzymes. as compared with batch cultivation, beta-galactos ... | 1977 | 330363 |
| involvement of uv-induced protein in the reinitiation of dna replication in uv-irradiated escherichia coli. | | 1977 | 330368 |
| primary structure of protein s13 from the small subunit of escherichia coli ribosomes. | the experimental details which led to the determination of the complete primary structure of protein s13 from the small subunit of escherichia coli ribosomes are presented. s13 consists of 117 amino acid residues and has the following composition: asp6, asn2, thr6, ser6, glu6, gln2, pro4, gly11, ala11, cys1, val7, met2, ile12, leu9, tyr2, phe1, his3, lys11 and arg15. tryptophan was not found. the molecular weight of protein s13 as derived from the sequence shown in fig. 1 is 12970. the amino aci ... | 1977 | 330375 |
| humoral immune response to the heat-labile enterotoxin of escherichia coli in naturally acquired diarrhea and antitoxin determination by passive immune hemolysis. | acute- and convalescent-phase sera from 132 students attending a university in rural mexico were assayed for antibody against the heat-labile enterotoxin (lt) of escherichia coli by neutralization of lt activity in the y-1 adrenal cell assay and by passive immune hemolysis of lt-sensitized sheep erythrocytes. the two titration methods produced comparable results with respect to antitoxin responses detected. an inverse relationship was found between acute geometric mean antitoxin titer and the oc ... | 1977 | 330395 |
| gastrointestinal antibody responses in axenic mice to topically administered escherichia coli. | immunoglobulin levels were determined in gastrointestinal secretions of both conventional and axenic mice, as was the stability of the immunoglobulin classes in these secretions. axenic animals were then administered nonviable escherichia coli o111:b4 by topical application into the oral cavity. immunoglobulin (ig) a, igg1, and igg2 were detected in the gastrointestinal secretions, with an apparent gradation in stability (iga greater than igg1 greater than igg2) under the conditions investigated ... | 1977 | 330399 |
| enhanced susceptibility of mice to combinations of delta 9-tetrahydrocannabinol and live or killed gram-negative bacteria. | combinations of delta 9-tetrahydrocannabinol (delta 9-thc) and bacterial endotoxin were shown to be hyperadditively toxic for mice. a variety of purified lipopolysaccharide (lps) preparations elicted enhanced mortality in combination with delta 9-thc. escherichia coli o26:b6 lps (boivin preparation) at an essentially nonlethal dose of 2.5 mg/kg reduced the dose of delta 9-thc required to kill 50% of the treated mice from ca. 350 to 150 mg/kg. inbred balb, dba, and c3h/hecr mice, noninbred icr mi ... | 1977 | 330405 |
| local immune response to lipoprotein of the outer membrane of escherichia coli in experimental pyelonephritis. | the local immune response to the lipoprotein of the outer membrane of escherichia coli o6:k13:h1 was determined in experimental hematogenous pyelonephritis in rabbits. local antibody was analyzed with the enzyme-linked immunosorbent assay on newly synthesized protein from kidney. local or intrarenal antibody was detected by day 7 of infection, a few days later than serum antibody. the synthesis of antibody in immunoglobulin g class was present 6 days before the synthesis of immunoglobulin m anti ... | 1977 | 330406 |
| effect of alkali-treated lipopolysaccharide on the intracellular cations of human erythrocytes. | the adsorption to human erythrocytes of escherichia coli lipopolysaccharide treated by mild alkaline hydrolysis (h-lps) stimulated an increase in the intracellular na+ concentration and a decrease in the intracellular k+ concentration of the erythrocytes. erythrocytes treated by h-lps remained responsive to the membrane adenosine triphosphatase inhibitors ouabain and ethacrynic acid, indicating that hlps did not alter erythrocyte cations be depleting energy intermediates or uncoupling energy met ... | 1977 | 330408 |
| insect immunity. iii. purification and partial characterization of immune protein p5 from hemolymph of hyalophora cecropia pupae. | we previously showed that in pupae of hyalophora cecropia, eight hemolymph proteins (p1 through p8) were selectively synthetized after immunization (faye et al., infect, immun. 12:1426-1438, 1975). we also showed that a gross fractionation was obtained by a series of ammonium sulfate precipitations (designed a through d) and that protein p5 was enriched in fraction a. starting from fraction a, we have now purified protein p5 by using dialysis, isoelectric focusing, and hydroxylapatite chromatogr ... | 1977 | 330409 |