Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BACTERIOLYSIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources
PubMed1964

METHICILLIN-INDUCED LYSOZYME-SENSITIVE FORMS OF STAPHYLOCOCCI.

Aldrich, K. M. (The University of Kansas, Lawrence), and C. P. Sword. Methicillin-induced lysozyme-sensitive forms of staphylococci. J. Bacteriol. 87:690-695. 1964.-Staphylococcus aureus and S. epidermidis grown in the presence of sublethal amounts of methicillin were converted to enlarged spheres within 2 to 4 hr, as shown by phase microscopy, Gram stain, and electron microscopy. Addition of lysozyme to cells incubated in the presence of methicillin, and to methicillin-induced spheres suspended in hypotonic saline, caused lysis of methicillin-treated cells but not of untreated cells.

Bacteriolysis↗
PubMed1964

CELL-WALL COMPOSITION AND OSMOTIC FRAGILITY OF SELECTED MARINE BACTERIA.

Sud, I. J. (University of Florida, Gainesville), and M. E. Tyler. Cell-wall composition and osmotic fragility of selected marine bacteria. J. Bacteriol. 87:696-700. 1964.-Cell-wall composition of three marine pseudomonads, selected to represent a spectrum of osmotic fragilities, was determined and compared with that of Pseudomonas aeruginosa. The walls of the marine bacteria were composed predominantly of lipoprotein. No sugars, except glucosamine, were detected, and the reducing values were similar to the respective hexosamine values. These varied from 0.9 to 1.8%, the most osmotically fragile marine bacterium possessing the lowest amount of hexosamine in the wall. Possible relationship between wall hexosamine content and osmotic fragility was indicated.

Bacteria↗
PubMed1964

CULTIVATION OF LEPTOSPIRAE. II. GROWTH AND LYSIS IN SYNTHETIC MEDIUM.

Stalheim, O. H. V. (University of Wisconsin, Madison), and J. B. Wilson. Cultivation of leptospirae. II. Growth and lysis in synthetic medium. J. Bacteriol. 88:55-59. 1964.-Differences were found in the ability of leptospirae to grow in a synthetic medium; 43 strains, consisting of 16 serotypes, were tested and designated as either type I or type II. Type I leptospirae did not grow; type II grew and could be subcultured. The lytic effect of several lipids was measured with Leptospira pomona and L. canicola as representatives of type I and II leptospirae, respectively. L. pomona organisms were rapidly lysed by the monoolein of the synthetic medium and by other lipids as well; L. canicola cells were consistently more resistant. Although both organisms incorporated similar amounts of label when incubated in the presence of oleic-1-C(14) acid, only L. canicola grew in a modified, nonlytic synthetic medium. No differences were found in susceptibility to lysis between virulent and avirulent L. canicola organisms. Mutant type I leptospirae grown in synthetic medium had increased resistance to lysis by surface-active agents; they were poorly agglutinated by antiserum. The role of protein in the growth and antigenicity of type I leptospirae is discussed.

Bacteriolysis↗
PubMed1964

IMMUNOGENIC SUBSTANCES IN CULTURE FILTRATES AND LYSATES OF PASTEURELLA TULARENSIS.

Hatch, Melvin T. (University of Utah, Salt Lake City), and Paul S. Nicholes. Immunogenic substances in culture filtrates and lysates of Pasteurella tularensis. J. Bacteriol. 88:566-573. 1964.-Culture filtrates and lysates of Pasteurella tularensis were tested for immunogenicity in mice subsequently infected with either strain 425 or 425 F4G. The efficacy of the vaccines varied with dosage and was significantly dependent upon methods of preparation. The optimal procedures for the production of an immunologically potent vaccine included: (i) aging the cultures after growth under partial anaerobiosis at 37 C, and (ii) inactivating the cells with phenol or formaldehyde. An unusual "survival phenomenon" was suggested when mice were administered large doses of cell-free vaccines and subsequently large doses of moderately virulent P. tularensis. The data indicated that the filtrates and lysates elicited an immune response sufficient to protect against an active infection with strains 425 or 425 F4G, and that the challenge dose per se stimulated an enhanced immunity. Furthermore, this survival phenomenon was demonstrable when immunized mice were subsequently given massive doses of strain 425 and challenged with approximately 1,000 ld(50) of the fully virulent strain Schu. On the basis of our data, we have hypothesized that the protective antigens were released into the suspending medium as a result of alterations in the permeability of cells undergoing either complete or partial enzymatic degradation. We believe that the envelope antigens were released from the cell by mechanisms analogous to those causing leakage of intracellular constituents in cells maintained at an incubation temperature in an unfavorable growth environment.

Animals↗
PubMed1964

CELL-WALL LYSINS OF STAPHYLOCOCCUS AUREUS STRAINS INDUCED BY SPECIFIC TYPING PHAGES.

Ralston, Doris J. (University of California, Berkeley), and Mary McIvor. Cell-wall lysins of Staphylococcus aureus strains induced by specific typing phages. J. Bacteriol. 88:667-675. 1964.-At least 12 different phages induced the formation of soluble lysins (separable from the phages by ultracentrifugation). The lysins caused rapid clearing of heat-killed cells of all strains of Staphylococcus aureus tested, irrespective of the capacity of the phage to form plaques on living cells of the strain. The uninfected cells of the 12 strains contained a second lysin, an autolysin, released upon cellular autolysis. The autolysin preparations differed from the phage-induced lysins, in that they exhibited relatively high activity for lysing Micrococcus lysodeikticus and low activity for strain S. aureus K(1N), and were each specifically inhibited by antiserum prepared against purified autolysin from strain K(1). A third kind of lysin, virolysin, induced by polyvalent phage K, was differentiated from the lysins of the specific phages on the basis of its antigenic specificity and lack of action on M. lysodeikticus. All three kinds of lysins digested the mucopeptide portion of staphylococcal cell walls. No evidence was found that any of these lysins possessed specific host ranges which could be correlated with the lytic host range of the inducing phage.

Animals↗
PubMed1964

LYSIS-FROM-WITHOUT OF STAPHYLOCOCCUS AUREUS STRAINS BY COMBINATIONS OF SPECIFIC PHAGES AND PHAGE-INDUCED LYTIC ENZYMES.

Ralston, Doris J. (University of California, Berkeley) and Mary McIvor. Lysis-from-without of Staphylococcus aureus strains by combinations of specific phages and phage-induced lytic enzymes. J. Bacteriol. 88:676-681. 1964-Several typing phages, adsorbed in sufficient concentrations to their homologous propagating strains, altered the cell surface so as to render the cells sensitive to rapid and synergistic lysis by extra-cellular additions of wall lysins. Lysis was effected both by lysins induced by the individual phages and by phage K(1) virolysin. Phage K(1) also rendered cells sensitive to the lysins of the typing phages. With the exception of lysins from PS 53, 70, and 77, none of the lysins nor purified phages tested separately caused significant lysis of living cells. Lysis-from-without in Staphylococcus aureus appears to be a stepwise process: sensitization by phage followed by digestion of the wall by lysin.

Bacteriolysis↗
PubMed1964

DENSITY-GRADIENT PATTERNS OF STAPHYLOCOCCUS AUREUS CELLS AND CELL WALLS DURING GROWTH AND MECHANICAL DISRUPTION.

Huff, Eskin (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), Harriet Oxley, and Carol S. Silverman. Density-gradient patterns of Staphylococcus aureus cells and cell walls during growth and mechanical disruption. J. Bacteriol. 88:1155-1162. 1964.-Procedures capable of rapid disruption of Staphylococcus aureus cells with optimal release of intact cell walls were investigated. This search was implemented by observation of the flotation patterns of cells and subcellular particulate matter after centrifugation in a cesium chloride density gradient. A quantitative evaluation of the light-scatter throughtout the gradient was achieved by transfer of the entire density gradient into an optical cell with wedge-shaped cross section. When this cell was photographed under indirect illumination, each band of light-scattering material appeared on the negative as a shaded curve, with an area proportional to amount of that material present. A series of photographs of known amounts of cells and cell walls was used to estimate the amounts of these materials in mixtures of the two occurring during mechanical disruption. With the methods employed, time studies established the optimal time for release of cell walls as 5 min in a Braun shaker. The use of sucrose gradients in the further purification of cell walls, and chemical analysis of the isolated walls, are described.

Bacteriological Techniques↗
PubMed1964

TEMPERATURE-SENSITIVE MUTANTS OF BACILLUS SUBTILIS BACTERIOPHAGE SP3. II. IN VIVO COMPLEMENTATION STUDIES.

Nishihara, Mutsuko (University of California, Los Angeles), and W. R. Romig. Temperature-sensitive mutants of Bacillus subtilis bacteriophage SP3. II. In vivo complementation studies. J. Bacteriol. 88:1230-1239. 1964.-A plate-spotting procedure was used in initial attempts to group the temperature-sensitive Bacillus subtilis phage SP3 mutants by complementation. The results obtained did not show any clear patterns of reactions among the mutants. Crosses were, therefore, repeated in broth at a temperature of 49 C, which greatly reduced the extent of replication of each mutant type alone. The data on mixed infections indicated that there was a minimum of six complementation groups. Of the 12 isolates, 7 did not seem to complement with each other; the rest complemented with each other and with the seven noncomplementing mutants. There was a positive correlation between the complementation reaction of a pair and the recovery of wild-phenotype phages from a 49 C broth lysate. The relative proportion of phages capable of forming wild-phenotype plaques on plates incubated at 46 C to the total number of plaque-forming units was higher in a lysate of a mixed infection with two mutants than in lysates of each mutant alone. Moreover, this frequency was higher for a mixed lysate made at 49 C than for a lysate of the same two mutants made at 37 C. These observations suggested that genetic recombination might occur at 49 C, and that the increased recovery of wild-phenotype phages in lysates made at this temperature might be due to a selective advantage for these phages. Recombination experiments at 37 C with some complementing pairs gave frequencies of 2.0 to 4.8%. The ratio of wild-phenotype revertants to total phages in the stock lysates used for these crosses at 37 C was less than 10(-6). The noncomplementing mutants were not conclusively shown to be nonidentical.

Bacillus subtilis↗
PubMed1964

DRUG RESISTANCE OF ENTERIC BACTERIA. IV. ACTIVE TRANSDUCING BACTERIOPHAGE P1 CM PRODUCED BY THE COMBINATION OF R FACTOR WITH BACTERIOPHAGE P1.

Kondo, Eiko (Gunma University, Maebashi, Japan), and Susumu Mitsuhashi. Drug resistance of enteric bacteria. IV. Active transducing phage P1 CM produced by the combination of R factor with phage P1. J. Bacteriol. 88:1266-1276. 1964.-During an investigation of the transduction of R factors with phage P1, a phage lysate capable of transducing the character of chloramphenicol resistance (CM(r)) in extremely high frequency was obtained. The transduction of the CM(r) character with the lysate was consistently accompanied by lysogenization with the phage used for transduction. This lysate exhibits no beneficial effect with normal P1, and no effect is produced by decreasing the multiplicity of infection. A single infection with the phage allows the formation of plaques as well as CM(r) lysogenic cells at the center of the plaque. Both the transducing and plaque-forming activities of the lysate were lost by neutralization with anti-P1 phage serum, and its absorption to the host bacteria was enhanced by the addition of Ca(++). Thus, it was concluded that a derivative of P1 phage (P1 CM) was isolated which had not only the ability to transduce the CM(r) character but also the capacity to form plaques; i.e., the CM(r) gene of R factor is specifically associated with the genome of phage P1. No detectable differences were noted between P1 CM and normal P1 phage in density-gradient analyses in CsCl, in stability of lysogenization, in ability to transduce chromosomal markers, and in the mode of induction from lysogenic cells by ultraviolet irradiation. The instance of transduction of the CM(r) character described here may also be considered as an example of lysogenic conversion, in the sense that the alteration in CM(r) character is inseparable from lysogenicity.

Bacteria↗
PubMed1964

STABILIZATION OF STREPTOCOCCUS FAECALIS PROTOPLASTS BY SPERMINE.

Harold, F. M. (National Jewish Hospital, Denver, Colo.). Stabilization of Streptococcus faecalis protoplasts by spermine. J. Bacteriol. 88:1416-1420. 1964.-Lysis of protoplasts of Streptococcus faecalis subjected to osmotic shock was prevented by the presence of 10(-3)m spermine and other divalent cations. Protein and nucleic acids were largely retained, but compounds of low molecular weight were discharged into the medium and the capacity for glycolysis was lost. Under these conditions, spermine was bound to the protoplasts. It could not be removed by washing with water or nonelectrolytes, but was displaced by salts, polyanions, and polycations. Removal of the spermine restored the osmotic fragility of the protoplasts, which could once again be protected from lysis by impermeant solutes. Protoplasts were also stabilized, in the absence of osmotic shock, by prolonged incubation with cations in 0.5 m sucrose. By either procedure, the protoplasts became resistant not only to osmotic lysis but also to sonic oscillation. It is concluded that the stabilization of protoplasts resulted from ionic binding of the cation to acidic sites on the external surface of the plasma membrane. This conferred upon the membrane additional mechanical strength, perhaps by the cross-linking of subunits, but did not alter its permeability to extracellular solutes.

Bacteriolysis↗
PubMed1965

EFFECT OF CHOLESTEROL ON THE SENSITIVITY OF MYCOPLASMA LAIDLAWII TO THE POLYENE ANTIBIOTIC FILIPIN.

Weber, Morton M. (St. Louis University School of Medicine, St. Louis, Mo.), and Stephen C. Kinsky. Effect of cholesterol on the sensitivity of Mycoplasma laidlawii to the polyene antibiotic filipin. J. Bacteriol. 89:306-312. 1965.-The polyene antibiotic, filipin, inhibited growth and caused lysis of Mycoplasma laidlawii cells which had been cultured in the presence of cholesterol. The antibiotic did not inhibit growth and did not promote lysis of the organism when grown in the absence of cholesterol. These results constitute strong support for the contention that the presence of sterol in the cell membrane is a necessary prerequisite for polyene sensitivity. Higher concentrations of filipin were required to inhibit growth when serum was added to the assay medium than when it was absent. These results suggest binding of the antibiotic to some component in the serum and may partially account for the previous inability to demonstrate growth inhibition by low concentrations of the polyene antibiotics. The extent of growth inhibition due to filipin decreased upon prolonged incubation. Subculture in the presence of high concentrations of antibiotic indicated that the apparent reversal of inhibition was caused by emergence of a filipin-resistant cell population. It was also observed that cells, which originally were rapidly lysed by filipin and digitonin, were no longer responsive to the action of these agents upon incubation in sterol-free medium at 25 or 37 C for several hours. This effect could be prevented by keeping the cells at 2 C. These results may indicate that filipin-resistant cells carry out a metabolic conversion of membrane-localized sterol to a form which can no longer react with the antibiotic. Other possible causes of resistance, which cannot be excluded on the basis of the present data, are discussed.

Acholeplasma laidlawii↗
PubMed1965

PROTOPLAST LYSIS AND INHIBITION OF GROWTH OF BACILLUS LICHENIFORMIS BY BACITRACIN.

Snoke, John E. (University of California, Los Angeles), and Neal Cornell. Protoplast lysis and inhibition of growth of Bacillus licheniformis by bacitracin. J. Bacteriol. 89:415-240. 1965.-The growth of Bacillus licheniformis is inhibited by bacitracin, the antibiotic which the organism itself produces. The effect of the antibiotic is confined to the early growth phase of the organism. Bacitracin will produce a rapid lysis of protoplasts of B. licheniformis and Micrococcus lysodeikticus. The lytic process requires cadmium or zinc ions, and the rate and extent of lysis depends upon the amount of bacitracin and metal ion added. Although B. licheniformis and M. lysodeikticus differ markedly in their sensitivity to bacitracin, the protoplasts from these two organisms are equally susceptible to lysis by the antibiotic.

Bacillus↗
PubMed1965

OBSERVATIONS ON THE GROUP C STREPTOCOCCAL BACTERIOPHAGE AND LYTIC ENZYME SYSTEM.

Fox, Eugene N. (La Rabida-University of Chicago Institute, Chicago, Ill.), and Masako K. Wittner. Observations on the group C streptococcal bacteriophage and lytic enzyme system. J. Bacteriol. 89:496-502. 1965.-The phage-associated lytic enzyme of group C streptococci was assayed by measuring the solubilized portion of radioactive cell walls. By this sensitive assay system, the induced synthesis of the lytic enzyme was observed intracellularly during phage infection; at least half of the total enzyme was synthesized and remained intracellular during the eclipse period, and was then released with the liberation of mature phage. Lytic enzyme could be detected in only two of eight lysogenic strains during temperate-phage production after ultraviolet induction. Virulent phage purified by density-gradient centrifugation contained lytic enzyme presumably associated with the virus per se. No hyalyronidase was detected in association with the phage, nor was this enzyme induced during phage synthesis. Variant strains of group C streptococci, no longer serologically active, were isolated as phage-resistant mutants. These strains still adsorbed the phage, but without subsequent virus reproduction, indicating that the group polysaccharide was not the primary receptor for the virus.

Bacteriolysis↗