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At least 19 recordsLinked to original sources
PubMed1977

[Correlation between the intensity of spontaneous bacteriolysis and bacterial pollution in superficial waters].

A study on the determination of the intensity of spontaneous bacteriolysis in different samples of water from the hydrographic basin of Lorraine, has led us to propose a new way of expressing the spontaneous bacteriolytic power: PBSG. Its utilization has permitted us to establish correlations between the intensity of spontaneous bacteriolytic power and the degree of bacteriological pollution found in different places in the two rivers, the Moselle and the Meurthe. A very strong correlation has been shown between the rate of global spontaneous bacteriolysis after 6 days and the number of coliforms in the water.

Bacteriolysis↗
PubMed1979

Protamine and polyarginine bacteriolysis. Similarities in its mechanism with chromatin DNA picnosis.

Protamine and polyarginine had bacteriolytic effects indicating their primary sites of action as being wall components and showing bacterial diversity genetically determined. Shake-incubation was required in producing cell-lysis. Studies on Bacillus subtilis revealed a high polycation multiplicity per cell in lytic event displaying multihit lysing kinetics; bacteriolysis was inhibited by trypsin, pronase, purified polyanionic wall polysaccharide, and by dissociative actions of salt hypermolarities used in isolation of nucleic acids. The inactivation of polycation lytic abilities during bacteriolysis was accompanied by modifications in electrophoretic running of protamine and polyarginine. It is suggested as mechanism of cell-lysis, the multiple zonal surface condensations of polyanionic wall components by basic polypeptides, likely similar with chromatin DNA picnosis. This analogy is discussed.

Anti-Bacterial Agents↗
PubMed1977

[Humoral immunity aspects of meningococcal infection. I. A method of performing and the characteristics of the immune bacteriolysis reaction].

Immune bacteriolysis test with meningococcus, group A, was used for the purpose of serum antibody study. Meningococcus cultures with a bright orange fluorescence of the colonies in oblique illumination (the I type) proved to possess the greatest lysability. Guinea pig serum sorbed with meningococcus suspension was found to be the best source of the complement. Sera obtained after 1 to 3 days of rabbit immunization, containing mostly IgM antibodies, had the greatest bactericidal capacity. Only those fractions which contained IgM possessed bactericidal activity in the hyperimmune rabbit sera with a high IgG antibody concentration. No lytic activity was displayed against meningococcus by unfractionated hyperimmune sera.

Animals↗
PubMed1977

Bacteriolysis by immobilized enzymes.

Bacteriolytic enzymes produced by Achromobacter lunatus were immobilized in collagen membrane. Intact bacteria such as Pseudomonas solanacearum, Xanthomonas oryzae, Staphylococcus aureus, and Pseudomonas aeruginosa were lyzed with the bacteriolytic enzyme-collagen membrane. Relative activity of the bacteriolytic enzyme-collagen membrane against Pseu. solanacearum was about 2% of that of native bacteriolytic enzymes. No difference in the optimum pH was observed between immobilized enzymes and native enzymes. The bacteriolytic enzymes in the collagen membrane were stable against sodium chloride which was an inhibitor of the native bacteriolytic enzymes. Xanthomonas oryzae and Pseu. aeruginosa were continuously lyzed by a reactor containing the rolled bacteriolytic enzyme-collagen membrane.

Alcaligenes↗
PubMed2025

Characterization of the novel Cutibacterium acnes phage KIT08 and its associated pseudolysogenic bacterial isolate.

Cutibacterium acnes, formerly Propionibacterium acnes, is a Gram-positive bacterium commonly recognized as an important factor in acne vulgaris and infections associated with prosthetic medical devices. With the rise in antibiotic resistance, phage therapy has gained renewed attention as a promising alternative to antibiotics. In addition to a strict lytic cycle, some virulent phages may enter a pseudolysogenic state and exclude superinfections, thereby significantly limiting the applicability of these potential antimicrobial agents. However, the trade-off induced by phage infection of bacterial cells during this state and its molecular mechanism are yet to be confirmed, especially for C. acnes phages. In this study, a novel Cutibacterium acnes phage, KIT08, was isolated and characterized. It demonstrated rapid infectivity and moderately strong bacteriolysis. After infection of C. acnes NBRC 107,605, pseudolysogenic bacteria were collected and examined for physiological tradeoffs. The pseudolysogenic isolate exhibited slower growth and downregulation of the transcriptional levels of biofilm-producing genes, such as lipase 2 and hyaluronate lyase, leading to a decrease in biofilm formation. Additionally, a genomic study of phage KIT08 revealed that open reading frames 23 and 34 encode putative proteins homologous to repressor C and LTP proteins, which may play an important role in the induction of pseudolysogeny and superinfection exclusion in C. acnes.

Propionibacterium acnes↗
PubMed1977

A new type of penicillin resistance of Staphylococcus aureus.

Penicillin--"tolerant" Staphylococcus aureus strains are resistant to the lethal action of penicillins, but are inhibited by normal (low) concentrations. They are deficient in autolytic enzyme activity which appears to be necessary for bacteriolysis and the lethal action of penicillins. This "deficiency" is caused by a large excess of an inhibitor of autolysin. Seven such tolerant strains have been isolated from blood, bone, or sputum of patients who responded poorly to penicillin treatment of endocarditis, osteomyelitis, or staphylococcal pneumonia. These isolates were of different phage-types, and most showed cross-tolerance to the killing action of cephalosporins or vancomycin, antibiotics to which they were sensitive (inhibited). They were killed at normal rates by gentamicin, cycloserine, and rifampicin. Population analysis indicated that the proportion of tolerant organisms within a resistant strain is 7% or less; their ability to inhibit autolytic activity within their own and neighbouring cells appears to account for the net decreased autolytic activity of the entire strain; 44% of the bacteraemic strains studied showed penicillin tolerance. Tolerance is thus a common, clinically important form of penicillin resistance, that differs from previously described forms of pencillin resistance, that due to beta-lactamase, and that due to "intrinsic" (e.g., methicillin resistance) mechanisms.

Adult↗
PubMed1977

[Attempt to express the spontaneous global bacteriolytic power of water].

The utilization of a technique for the determination of spontaneous bacteriolytic power in surface waters has led us to propose a new way of expressing the spontaneous bacteriolytic power of water: PBSG. PBSG allows us to evaluate the intensity of global spontaneous bacteriolysis and to compare the global spontaneous bacteriolytic powers of different water samples.

Bacteriolysis↗
PubMed1979

Effect of leukocyte hydrolases on bacteria. XIII. Role played by leukocyte extracts, lysolecithin, phospholipase a2, lysozyme, cationic proteins, and detergents in the solubilization of lipids from Staphylococcus aureus and group A streptococci: relation to bactericidal and bacteriolytic reactions in inflammatory sites.

The bactericidal and bacteriolytic effects of lysolecithin (LL) and egg-white lysozyme (LYZ) on Staph. aureus and group A streptococci and the solubilization of phospholipids from the bacterial membranes by these agents was studied. Low concentrations of lysolecithin (1--10 microgrames/ml) are highly bactericidal for Steph. aureus and group A streptococci, but induce neither bacteriolysis nor solubilization of a substantial amount of membrane phospholipids. On the other hand, while LL at greater than 50 micrograms/ml causes substantial lipid release, a combination of LL and LYZ is absolutely needed to solubilize lipids from streptococci. This combination is, however, not bacteriolytic for this microrganism. The solubilization of lipids from staphylococci by LL is much faster than that induced in streptococci by LL + LYZ. The solubilization of the bulk of membrane lipids from staphylococci can also be achieved by Triton X-100 and by sodium lauryl sulfate and from group A streptococci by Triton X-100 plus LYZ. A variety of other detergents (e.g., Cetavlon, sodium taurocholate, cetyl pyrdinium chloride) have no lipid-releasing properties even in the presence of LYZ. The release of lipids by LYZ (in the presence of LL) from group A streptococci is related to its enzymatic activity, on a still unknown substrate, but not to its cationic nature as this muramidase cannot be replaced by a variety of cation substances (histone, polylysin, leukocyte cationic proteins, polymyxin B, and spermidine). The release of lipids from staphylococci by LL is not inhibited by a variety of anionic and cationic polyelectrocytes (heparin, liquoid, chondroitin sulfate, DNA histone, and polylysine) which markedly inhibit the release of lipids from group A streptococci by LL and LYZ. Streptococci that had been cultivated in the presence of subinhibitory concentrations of penicillin G lose their membrane phospholipids to a larger extent and by much smaller concentrations of LL and LYZ, as compared to controls, suggesting that the interference with the synthesis of the peptidoglycan increases the accessibility of the cell membrane to the lipid-releasing agents. The mechanism by which LL collaborates with LYZ in lipid release is still not known. The possible role of bacterial lipids and lyso compounds in the control of bacterial survival in inflammatory sites is briefly discussed.

Cell Membrane↗
PubMed1979

Bactericidal activity of the alternative complement pathway generated from 11 isolated plasma proteins.

Exposure of E. coli K12 W1485 to the cytolytic alternative pathway assembled from the 11 isolated pathway proteins resulted in killing of the bacteria, as evidenced by loss of viability. Lysis of the bacteria required introduction of lysozyme into the reaction mixture. The time-course and dose dependency of bacteriolysis in the isolated system were identical to those in C4-depleted serum. The bacteriolytic activity of the pathway was highly dependent on the concentration of the pathway proteins and became insignificant at 1:16 physiological concentration. Electron microscopic visualization of killed and of lysed bacteria revealed numerous complement membrane lesions and partial disintegration of the outer phospholipid membrane. Scanning electron microscopy showed that killed bacteria were enlarged, partially collapsed and exhibited irregular surface protrusions. Lysed bacteria were fragmented and appeared polymorphic. This study demonstrates that the alternative pathway, in absence of immunoglobulins, has the potential or eradicating gram-negative bacteria.

Blood Bactericidal Activity↗
PubMed1978

Role of immunity in the clearance of bacteremia due to Haemophilus influenzae.

The role of antibodies to capsular and somatic antigens in the clearance of Haemophilus influenzae was investigated by active and passive immunization. The clearance index (k) and the proportion of strain b organisms cleared 30 min after intravenous administration (deltaY30) were greater in eight-week-old actively immunized rats (k = 0.693, deltaY30 = 4.07) than in nonimmune animals (k = 0.075, deltaY30 = 0.95)(P less than 0.025 for all); however, clearance correlated imprecisely with titers of bactericidal or anticapsular antibody. In three-week-old rats, intranasal immunization with strain b or U significantly increased (P less than 0.005) the rate of clearance of strains b and U. Passive immunization with antibodies to somatic or capsular antigens significantly increased the rate of clearance (P less than 0.001) and the proportion of bacteria cleared (P less than 0.05) with all test strains. The increased clearance associated with passive immunization correlated with increased splenic uptake of 32P-labeled H. influenzae (r = 0.83, P less than 0.025). Analysis of the disappearance of viable organisms and bacterial 32P suggested that bacteriolysis of H. influenzae did not occur during clearance of the bacteremia. Either antibody to capsular antigen or antibody to somatic antigen, administered or evoked in rats, accelerates intravenous clearance of H. influenzae by promotion of reticuloendothelial phagocytosis.

Animals↗
PubMed1978

Excretion of lipoteichoic acid by group A streptococci. Influence of penicillin on excretion and loss of ability to adhere to human oral mucosal cells.

Group A streptococci were grown in the presence of [2-(3)H]glycerol. Concentrated suspensions of the labeled organisms were incubated with and without penicillin. [(3)H]Glycerol-labeled material accumulated in the supernates in increasing amounts with increasing concentrations of penicillin, ranging from 0 to 50 U/ml. The excretion of labeled material occurred in the absence of nucleic acid synthesis or bacteriolysis indicating that the phenomenon is independent of cell multiplication or decay. The accumulation of label was paralleled by an accumulation of erythrocyte-sensitizing material measured by passive hemagglutination tests for lipoteichoic acid antigen, indicating that a portion of the labeled material possessed the properties of lipoteichoic acid. Culture supernates were fractionated by column chromatography, and the materials obtained were analyzed by electrophoresis on sodium dodecyl sulfate polyacrylamide, thin-layer chromatography, and paper chromatography. The ability of the same materials to bind to human erythrocytes and epithelial cells was tested. The culture supernate contained lipoteichoic acid, deacylated lipoteichoic acid, glycerol phosphate, and free glycerol. Penicillin caused an increase in the amounts of each of the excreted materials. Streptococci that were stimulated with penicillin to lose their lipoteichoic acid (previously shown to mediate adherence of group A streptococci) lost their ability to adhere to buccal mucosal cells, suggesting that penicillin may influence bacterial ecology by mechanisms other than killing sensitive organisms.

Adhesiveness↗
PubMed1979

Disseminated gonococcal infections (DGI).

Neisseria gonorrhoeae infects superficial membranes of the eyes, oropharynx, genital tract, and rectum prior to dissemination. Gonococcal isolates cultured from patients with disseminated gonococcal infections (DGI) show resistance to serum bacteriolysis, are very sensitive to penicillin, and have characteristic growth requirements for certain amino acids. DGI is characterized by recurrent chills and fever, polyarthralgias and/or polyarthritis (with effusions), and skin lesions. The skin manifestations of DGI include vesicopustules, hemorrhagic bullae, and petechiae. These lesions are found over the juxta-articular areas of the hands (extensor surfaces) or the feet (dorsal aspects). Focal and disseminated gonococcal infections are now treated with several types of penicillin regimens, tetracycline, or spectinomycin.

Anti-Bacterial Agents↗
PubMed1979

[Deoxyribonucleic acids from Pasteurella multocida and Pasteurella haemolytica].

Pasteurella multocida and P. haemolytica strains contain between 1.5 and three per cent phosphorus, between nine and 14 per cent nitrogen, between two and four per cent DNA, and between five and 18 per cent RNA, the precise figures depending on culturing conditions. High-molecular DNA may be isolated by means of bacteriolysis, using deoxycholate or dodecylsulphate and the usual steps of purification, with yield and purity differing by strains. DNA with sufficient purity can be obtained from Sepharose 2 B by gel chromatography. The isolated DNA yields were characterised, base values being between 37 and 38 per cent GC for P. haemolytica and between 41 and 48 per cent GC for P. multocida. Highly suitable precursors to DNA synthesis for tritium labelling are 3H-thymidine, which is incorporated in excess of 3H-thymine by a factor of 255, as well as 3H-uracil, with its activity being recovered also from the pyrimidine bases of DNA via pyrimidine biosynthesis.

Chromatography, Gel↗
PubMed1976

Frog lysozyme. I. Its identification, occurrence as isozymes, and quantitative distribution in tissues of the leopard frog, Rana pipiens.

In the course of examining the etiology of the Lucké renal adenocarcinoma of the frog, Rana pipiens, it was found that organs of the normal adult contain bacteriolytic enzymes. These enzymes all satisfied the six criteria for the identification of lysozymes and at least eight forms were separable by polyacrylamide gel electrophoresis. Their qualitative and quantitative distribution was organ-specific. All eight isozymes were found in normal kidney, while liver and spleen contained seven forms; skin, six; ovarian egg, five; and serum, two. In quantitative assays using a radial diffusion test, spleen had the greatest lysozyme concentration, followed in descending order by kidney, liver, skin, and ovary. Serum contained very low amounts. In terms of enzyme activity per animal, ovary was the highest ranking organ. As such a large number of lysozyme isozymes has not been reported in any other organism, their origins and functions are considered in the context of their presence in an ectotherm.

Animals↗
PubMed1977

Lysosomal enzymes of phagocytic cells as humoral mediators of inflammation: modulation of their release by cyclic nucleotides.

The origin of lysosomes in phagocytic cells is described. Studies on their characterization by both morphological and biochemical methods are summarized. Lysosomal enzymes of both polymorphonuclear leukocytes and macrophages can be released by exocytosis in response to a variety of inflammatory stimuli. This response is modulated by cyclic nucleotides. In the polymorphonuclear leukocyte cAMP inhibits enzyme release while cGMP enhances release; the effects of the cyclic nucleotides are less clear in the macrophage. The possible involvement of microtubules and microfilaments in the release process is discussed.

Bacteriolysis↗