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

A gentle technique for preparing spheroplasts of Capnocytophaga ochracea strain 25 is described. Cells in the exponential phase were washed with 1.0 M-NaCl, agitated in 1.0 M-NaCl for 2 h at 30 degrees C and exposed to lysozyme in a Tris/salts buffer, pH 7.0. This procedure resulted in 98% spheroplast formation with complete removal of the peptidoglycan layer as detected by both phase-contrast and electron microscopy in combination with chemical analysis.
J Gen Microbiol 1985 May
PMID:Induction of spheroplasts in Capnocytophaga ochracea. 402 Mar 45

beta-N-Acetylglucosaminidase has been purified from the walls of Bacillus subtilis 168 and compared with the other known autolysin, N-acetylmuramyl-L-alanine amidase (amidase). The beta-N-acetylglucosaminidase was a dimer in LiCl buffers with a sub-unit molecular weight of 90000 and a pH optimum of about 5.0. It was very sensitive to proteolytic enzymes and was critically activated by 0.1 to 0.2 M-LiCl. It was insoluble in concentrations of LiCl lower than 0.05 to 0.1 M. It was less strongly bound to walls than was the amidase, which was a monomer of molecular weight 30000 to 40000 in LiCl buffers. The beta-N-acetylglucosaminidase is an endo-enzyme and showed no exo-activity. Lysozyme-like enzyme (muramidase) activity was undetectable in the wall extracts examined.
J Gen Microbiol 1984 Sep
PMID:Purification and properties of autolytic endo-beta-N-acetylglucosaminidase and the N-acetylmuramyl-L-alanine amidase from Bacillus subtilis strain 168. 615 66

A new procedure has been developed for the isolation of the chromosome complex, termed chromatin, from Escherichia coli. The bacteria were subjected to low ionic strength and T4 lysozyme, followed by detergent treatment analogous to that employed for the isolation of eukaryotic chromosomes. The chromatin was an insoluble viscous material which contained approximately equal amounts of DNA and RNA. The protein content of the chromatin was almost three times greater than the nucleic acid content. Electron microscopy revealed that the chromatin was highly condensed, having multiple loops and beaded structures with various diameters. The chromatin could be completely solubilized by both micrococcal nuclease and DNAase I, whereas RNAase had no effect. The initial degradation by micrococcal nuclease resulted in the production of a DNA-protein particle, sedimentation coefficient 10S, and an RNA-protein complex of 24S. Further degradation led to a decrease in sedimentation coefficient of the DNA-protein complex, but not of the RNA-protein particle. The peak size of the DNA of the initial DNA-protein particle was approximately 2400 bp. The action of micrococcal nuclease also resulted in the production of several discrete RNA species of various sizes. Several low molecular weight proteins (12000-27000) were found in the DNA-protein complex. The DNA-binding protein HU was present in the undigested chromatin; varying amounts of HU were, however, detected in the DNA-protein and RNA-protein particles.
J Gen Microbiol 1982 Dec
PMID:Isolation, properties and nucleolytic degradation of chromatin from Escherichia coli. 619 Sep 86

The localization of the Pseudomonas aeruginosa lectins (PA-I and PA-II) was studied using methods of osmotic shock, freezing and thawing and spheroplast formation. Very slight release of the two lectins occurred when P. aeruginosa was exposed to magnesium-osmotic shock or was frozen and thawed. Under these conditions, release of the periplasmic 5'-nucleotidase occurred, whereas no release of cytoplasmic glucose-6-phosphate dehydrogenase activity was detected. Formation of spheroplasts from P. aeruginosa by gradual removal of the bacterial envelopes revealed low lectin activity in the treatment fluids. Osmotic shock treatment of the lysozyme treated mureinoplasts resulted in low release of glucose-6-phosphate dehydrogenase and the two lectins (10-13%) and a considerable activity (38.4%) of 5'-nucleotidase. The presence of the lectins on the outer and the cytoplasmic membranes enabled intact cells and spheroplasts of P. aeruginosa to agglutinate papain-treated human erythrocytes. These results indicate that the two lectins are located mainly in the cytoplasm with small fractions on the cytoplasmic and outer membranes and in the periplasmic space.
J Gen Microbiol 1983 Oct
PMID:The intracellular localization of Pseudomonas aeruginosa lectins. 631 95

Photobacterium leiognathi closely resembles Escherichia coli with respect to cell lysis by lysozyme, and the fractionation of outer and cytoplasmic membranes. The two organisms differ in their phospholipid contents and, more significantly, in outer membrane protein compositions.
J Gen Microbiol 1983 May
PMID:Comparative biochemistry of the cell envelopes of Photobacterium leiognathi and Escherichia coli. 635 61

Protoplasts were prepared from Streptococcus sanguis and some S. mutans serotypes by use of lysozyme (EC 3.2.1.17) under particular conditions: cells had to be grown in DL-threonine (20 mM) and harvested in early exponential phase. The efficiency of protoplast formation was enhanced by two additional steps: plasmolysis (in 12% PEG), prior to addition of lysozyme, and a swirling phase, after the enzymic action. This procedure allowed us to obtain clean protoplasts, with only 0.5% contamination by bacterial cell walls. Up to 90% protoplast lysis was obtained in 0.5 M-NaCl. Cytoplasmic membrane purification was achieved by centrifugation on a glycerol cushion.
J Gen Microbiol 1983 Oct
PMID:Protoplast and cytoplasmic membrane preparations from Streptococcus sanguis and Streptococcus mutans. 636 Dec 17

Three sporulation mutants have been isolated which produce spores with an atypical resistance phenotype, i.e. they are sensitive to organic solvents and heat but resistant to lysozyme. All three mutants produced serine protease, alkaline phosphatase and glucose dehydrogenase which are biochemical marker events for stages I, II and III. Two of the three mutants produced dipicolinic acid, a late marker, but the third was defective in its production. Heat-resistance was not restored to any of the mutants by the provision of exogenous dipicolinate. Gel electrophoresis showed that the mutant spores had similar patterns of spore coat proteins to the wild-type and electron microscopy revealed no significant structural differences. The three mutations responsible for the phenotypes of the mutant spores lie in the phe-argA region of the Bacillus subtilis chromosome. Recombination index values indicate that the mutations are in three separate genes. They define at least two new sporulation loci, designated spoVH and spoVJ.
J Gen Microbiol 1983 Feb
PMID:SpoVH and spoVJ--new sporulation loci in Bacillus subtilis 168. 640 8

A method has been established which isolated polysomes from the lysozyme/EDTA-shocked cyanobacterium, Nostoc sp. MAC. In a typical preparation the total recovery of RNA as polysomes was 83%, in which 77% of the polysome fraction was present at sizes greater than 5-mers and 23% as 2-4-mers. Messenger RNA isolated from such a preparation of polysomes produced a 10-fold stimulation in the incorporation of [35S]methionine into polypeptides by a cell-free system of Escherichia coli. The in vitro-synthesized polypeptides were analysed on an SDS-polyacrylamide gradient gel together with in vivo-labelled proteins of Nostoc sp. MAC: seven polypeptides co-migrated with the in vivo-synthesized products. This is the first report of the expression of cyanobacterial messenger RNA in a heterologous cell-free system from E. coli; the efficiency of the system is discussed.
J Gen Microbiol 1983 Aug
PMID:Isolation of polysomes from Nostoc sp. MAC and translation of messenger RNA in a heterologous cell-free system. 641 28

A lytic enzyme was isolated and purified from PL-1 phage-induced lysates of the host Lactobacillus casei ATCC 27092. The molecular weight of the enzyme was about 30000. Maximum activity on the lysis of the host cell walls occurred at pH 6.0-6.5 and at 45 degrees C. The enzyme activity was inhibited by heavy metal ions, SH- and serine-enzyme inhibitors and o-phenanthroline. The reducing end of the enzymic digest was muramic acid and the enzyme was considered to be an endo-N-acetylmuramidase. However, the enzyme differed from the other known N-acetylmuramidases including hen's egg-white lysozyme in several enzymic properties.
J Gen Microbiol 1984 Feb
PMID:An N-acetylmuramidase induced by PL-1 phage infection of Lactobacillus casei. 642 95

Twenty-nine mutants blocked during stage V of sporulation have been isolated following directed mutagenesis of the lys-1 region of the Bacillus subtilis 168 chromosome. All of a sample of eight mutants tested are unaffected in sporulation marker events up to stage IV but did not produce dipicolinic acid. They produced stable 'phase white' spores that were released from the mother cell, and were partially resistant to toluene and lysozyme but sensitive to chloroform and heat. Mutation spoV A89, known to be in the lys-1 region, showed similar phenotypic characteristics. Three-factor transformation crosses and recombination indices showed that the new mutations and spoV A89 lie in a single linkage group, which maps between lys-1 and another sporulation locus, spoIIA. The size of the spoV A locus is such that it probably contains several genes, and these may be contiguous with the cluster of genes included within the spoIIA locus.
J Gen Microbiol 1984 Aug
PMID:Genetic and phenotypic characterization of a cluster of mutations in the spoVA locus of Bacillus subtilis. 643 57


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>