Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oligonucleotides were end-labelled with digoxigenin (DIG), chemically at the 5'-end or enzymically at the 3'-end. Following specific in situ hybridization of these probes to intracellular rRNA molecules, the hybrids were detected with anti-DIG Fab fragments labelled with fluorescent dyes. The antibody fragments penetrated through the bacterial cell periphery and specifically bound to their antigens. Probe-conferred and non-specific fluorescence per cell were quantified by flow cytometry and compared to values obtained with end-labelled fluorescent probes. The DIG reporter molecules could also be detected in whole fixed cells by antibodies labelled with either alkaline phosphatase or horseradish peroxidase. The penetration of the large antibody-enzyme complexes into the cells required lysozyme/EDTA treatment prior to the hybridization and has so far only been achieved for Gram-negative bacteria. This technique has the potential for significant signal amplification as compared to the fluorescently end-labelled oligonucleotides hitherto used for single cell identification in microbial ecology. Moreover, it can be used instead of fluorescent assays in natural samples showing autofluorescence.
J Gen Microbiol 1991 Dec
PMID:Identification of single bacterial cells using digoxigenin-labelled, rRNA-targeted oligonucleotides. 172 65

Staphylococcus aureus H was grown for 4 generation times with various sub-growth-inhibitory concentrations of beta-lactam antibiotics specific for particular penicillin-binding proteins (PBPs) - PBP2, clavulanic acid; PBP3, methicillin; PBP4, cefoxitin - and also with the non-specific benzylpenicillin. Isolated cell walls were digested with Chalaropsis muramidase and the resulting peptidoglycan fragments were fractionated by HPLC into disaccharide-peptide monomers and cross-linked dimers, trimers, tetramers and greater oligomers. The pattern of relative fragment concentrations with increasing amounts of drug was roughly the same regardless of the antibiotic used, monomers and dimers increasing while trimers and tetramers changed little and oligomers decreased rapidly. The patterns resembled closely those predicted by the 'random addition' model for multiple cross-link formation and not at all those predicted by the 'monomer addition' model. The O-acetylation of the peptidoglycan remained essentially unaffected under all these conditions. S. aureus MR-1, a constitutive producer of PBP2', gave similar results when treated with methicillin.
J Gen Microbiol 1991 Jul
PMID:Cross-linking and O-acetylation of peptidoglycan in Staphylococcus aureus (strains H and MR-1) grown in the presence of sub-growth-inhibitory concentrations of beta-lactam antibiotics. 195 58

The methods of cell lysis by lysozyme in tris-EDTA-sucrose with the consequent disruption of spheroplasts by the osmotic shock were used to obtain the total membranes from the intact or temperature-inactivated Rickettsia prowazekii. Detergents solubilization methods were used for analysis of outer membrane proteins. Sarcosyl insoluble material is shown to contain the main 134, 31, 29.5 and 25 Kd proteins, the minor 78, 60, 42, 17 Kd proteins, while the mixture of both membranes possess a more complex composition. Treatment of total membranes by the 2% octylglycoside results in elimination of the 31 Kd polypeptide. Inactivated Rickettsia can be used for isolation of the outer layer proteins diminishing the risk of working with this pathogenic microorganism.
Mol Gen Mikrobiol Virusol 1990 Apr
PMID:[Methods of isolation and polypeptide composition of membrane fractions of Rickettsia prowazekii]. 211 32

Chemotaxonomic data for strains of Actinobacillus, Haemophilus and Pasteurella spp. were analysed using three multivariate statistical strategies: principal components, partial least squares discriminant, and soft independent modelling of class analogy. The species comprised Actinobacillus actinomycetemcomitans. Haemophilus aphrophilus, H. paraphrophilus, H. influenzae, Pasteurella multocida, P. haemolytica and P. ureae. Strains were characterized by cell sugar and fatty acid composition, lysis kinetics during EDTA and EDTA plus lysozyme treatment, and methylene blue reduction. In total 23 quantitative variables were compiled from chemotaxonomic analyses of 25 strains. A. actinomycetemcomitans and H. aphrophilus formed distinct classes which differed from those of H. paraphrophilus, H. influenzae and Pasteurella spp. All characterization variables, except those describing fatty acid content, contributed significantly to inter-species discrimination.
J Gen Microbiol 1990 Mar
PMID:Multivariate analysis of quantitative chemical and enzymic characterization data in classification of Actinobacillus, Haemophilus and Pasteurella spp. 211 66

The basidiomycete Schizophyllum commune produces an extracellular bacteriolytic enzyme when grown on heat-killed cells of Bacillus subtilis as sole C, N and P source. The enzyme catalyses the dissolution of isolated B. subtilis cell walls at an optimum pH of 3.2-3.4, releasing muramyl reducing groups, which indicates that it is a muramidase. Although low levels of enzyme activity are present when the fungus is grown in the absence of bacteria, full enzyme production appears to be induced by bacterial cells and repressed by glucose. Whole bacteria are not lysed by the enzyme at pH 3.3, but are rendered osmotically fragile, and lyse when the pH is raised to 7 or higher. The muramidase is effective against several Gram-positive bacteria but did not lyse any of the Gram-negative species tested.
J Gen Microbiol 1990 Nov
PMID:A bacteriolytic muramidase from the basidiomycete Schizophyllum commune. 212 98

The nucleotide sequence of a 3.6 kb DNA fragment containing a cellodextrinase gene (celA) from Ruminococcus flavefaciens FD-1 was determined. The gene was expressed from its own regulatory region in Escherichia coli and a putative consensus promoter sequence was identified upstream of a ribosome binding site and a TTG start codon. The complete amino acid sequence of the CelA enzyme (352 residues) was deduced and showed no significant homology to cellulases from other organisms. Two lysozyme-type active sites were found in the amino-terminal third of the enzyme. In E. coli the cloned Cel A protein was translocated into the periplasm. The lack of a typical signal sequence, and the results of transposon phoA mutagenesis experiments indicated that CelA is secreted by a mechanism other than a leader peptide.
Mol Gen Genet 1990 Jul
PMID:Nucleotide sequence of the celA gene encoding a cellodextrinase of Ruminococcus flavefaciens FD-1. 212 44

The nucleotide sequence of an 852 base pair (bp) DNA fragment containing the entire gene coding for thermostable beta-1,3-1,4-glucanase of Bacillus macerans has been determined. The bglM gene comprises an open reading frame (ORF) of 711 bp (237 codons) starting with ATG at position 93 and extending to the translational stop codon TAA at position 804. The deduced amino acid sequence of the mature protein shows 70% homology to published sequences of mesophilic beta-1,3-1,4-glucanases from B. subtilis and B. amyloliquefaciens. The sequence coding for mature beta-glucanase is preceded by a putative signal peptide of 25 amino acid residues, and a sequence resembling a ribosome-binding site (GGAGG) before the initiation codon. By contrast with the processed protein, the N-terminal amino acid sequence constituting the putative leader peptide bears no or only weak homology to signal peptides of mesophilic Bacillus endo-beta-glucanases. The B. macerans signal peptide appears to be functional in exporting the enzyme to the periplasm in E. coli. More than 50% of the whole glucanase activity was localized in the periplasmic space and in the supernatant. Whereas homology to endo-1,4-beta-glucanases is completely lacking, a weak amino acid homology between the sequence surrounding the active site of phage T4 lysozyme and a sequence spanning residues 126 through 161 of B. macerans endo-beta-glucanase could be identified.
Mol Gen Genet 1990 Jul
PMID:Structure of the beta-1,3-1,4-glucanase gene of Bacillus macerans: homologies to other beta-glucanases. 227 30

Modification of the alkaline lysis at elevated temperature technique is proposed isolation of plasmid DNA from lactobacilli. Modification consists of colorimetric control of culture phase during the biomass growth, pH control at the probes treatment with lysozyme and alkaline solution of natrium dodecylsulfate by adding the indicator bromcrezolpurple into the medium for biomass growth. The high concentration of lysozyme is used (10 mkg.ml-1). Lactobacilli are lysed at 2 min incubations of the probes with the lytic solution in the boiling water bath. The treatment of the probes by proteinase K, by the mixture of chloroform:phenol:isoamyl spirit (25:24:1 vol/vol/vol) and by diethylpirocarbonate increased considerably the quality of the obtained DNA preparations. The modified technique is suitable for isolation of the plasmid DNA from lactobacilli of different species, enterococci, streptococci and other lactic bacteria. The connection of antibiotic resistance marker and the plasmid profile of lactobacilli under different conditions with the presence of the plasmid DNA- protein complex is discussed.
Mol Gen Mikrobiol Virusol 1990 Mar
PMID:[Optimization of the method of isolation of microamounts of plasmid DNA from lactobacilli]. 236

Shaken cultures of Streptomyces venezuelae ISP5230 in minimal medium with galactose and ammonium sulphate as carbon and nitrogen sources, respectively, showed extensive sporulation after 72 h incubation at 37 degrees C. The spores formed in these cultures resembled aerial spores in their characteristics. The ability of the spores to withstand lysozyme treatment was used to monitor the progress of sporulation in cultures and to determine the physiological requirements for sporulation. In media containing ammonium sulphate as the nitrogen source, galactose was the best of six carbon sources tested. With galactose S. venezuelae ISP5230 sporulated when supplied with any of several nitrogen sources; however, an excess of nitrogen source was inhibitory. In cultures containing galactose and ammonium sulphate, sporulation was suppressed by a peptone supplement. The onset of sporulation was accompanied by a drop in intracellular GTP content. When decoyinine, an inhibitor of GMP synthase, was added to a medium containing starch and ammonium sulphate, a slight increase in sporulation was seen after 2 d. The suppression of sporulation by peptone in liquid or agar cultures was not reversed by addition of decoyinine. A hypersporulating mutant of S. venezuelae ISP5230 was altered in its ability to assimilate sugars. In cultures containing glucose the mutant sporulated more profusely than did the wild-type and did not acidify the medium to the same extent. However, the suppressive effect of glucose on sporulation was not merely a secondary result of acid accumulation.
J Gen Microbiol 1990 Mar
PMID:Sporulation of Streptomyces venezuelae in submerged cultures. 239 93

The outer membrane of Campylobacter coli, C. jejuni and C. fetus cell envelopes appeared as three fractions after sucrose gradient centrifugation. Each outer membrane fraction was contaminated with succinate dehydrogenase activity from the cytoplasmic membrane fraction. Similarly the inner membrane fraction was contaminated with 2-ketodeoxyoctonate and outer membrane proteins including the porin(s). The separation of these two membranes was not facilitated by variations in lysozyme treatment, cell age, presence or absence of flagella, or longer lipopolysaccharide chain length. Sodium lauroyl sarcosinate extraction resulted in an outer membrane fraction which contained some inner membrane contamination and produced multiple bands upon sucrose gradient centrifugation. Triton X-100 extraction removed the inner membrane from the outer membrane and Triton X-100/EDTA treatment extracted lipopolysaccharide-rich regions of the outer membrane which contained almost exclusively the Campylobacter porin(s). These data indicated that the inner and outer membranes of the Campylobacter cell envelope were very difficult to separate, possibly because of extensive fusions between these two membranes.
J Gen Microbiol 1988 Nov
PMID:Comparison of methods used to separate the inner and outer membranes of cell envelopes of Campylobacter spp. 247 28


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