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)

Takeya, Kenji (Kyushu University, Fukuoka, Japan), Kazuhito Hisatsune, and Yasuko Inoue. Mycobacterial cell walls. II. Chemical composition of the "basal layer." J. Bacteriol. 85:24-30. 1963.-Chemical composition of the "basal layer" of the mycobacterial cell wall was determined. The layer contained 35% amino acids, 41.5% reducing sugars (mainly composed of arabinose and galactose), 13.8% amino sugars (glucosamine and muramic acid, 2:1), and 7.7% lipid. The main amino acids were alanine, glutamic acid, and diaminopimelic acid. Their molar ratio was approximately 2:2:1. The main difference in chemical composition between the cell wall and the basal layer was found in lipid content. According to the chemical composition, the basal layer resembles the walls of gram-positive bacteria, while the mycobacterial cell wall resembles the walls of gram-negative bacteria. The basal layer was thoroughly disintegrated by lysozyme digestion, and was considered to be an inner layer of the wall, conferring shape and rigidity on the mycobacterial cell wall.
...
PMID:Mycobacterial cell walls. II. Chemical composition of the "basal layer". 1398 4

Spore integuments of Bacillus coagulans were prepared containing nearly all the hexosamine and alpha, epsilon-diaminopimelic acid (DAP) present in intact spores. Subsequent autolytic action resulted in the destruction and removal of the residual cortical structure and "cortical membrane" leaving the appearance of the inner and outer spore coats unchanged in electron micrographs. Concurrently, all the hexosamine and DAP in the preparation was released mainly as non-diffusible mucopeptide containing alanine, glutamic acid, DAP, and all the glucosamine and muramic acid. Some diffusible peptides containing alanine, glutamic acid, and DAP were also present but there was little protein or carbohydrate. Lysozyme digestion of integument preparations from heated spores of Bacillus 636, B. subtilis, B. coagulans, and B. stearothermophilus specifically removed the residual cortex and cortical membrane with the release of the mucopeptide. In B. cereus T, only the residual cortex and part of the mucopeptide were solubilized by lysozyme. The effect of several reagents and enzymes upon the appearance and removal of hexosamine from B. coagul ans spore integuments is reported. The results show that spore mucopeptide is mainly located in the residual cortex and cortical membrane and suggest that these structures consist essentially of mucopeptide. The implications of these results in relation to the "contractile cortex" theory of heat resistance in spores are discussed.
...
PMID:Location and composition of spore mucopeptide in Bacillus species. 1399 17

Wiley, W. R. (Washington State University, Pullman), and J. L. Stokes. Effect of pH and ammonium ions on the permeability of Bacillus pasteurii. J. Bacteriol. 86:1152-1156. 1963.-Cell suspensions of Bacillus pasteurii require an alkaline pH (8.5 to 9.0) and NH(4) (+) for the oxidation of low concentrations (4 mum) of fumaric acid, glutamic acid, alanine, and other oxidizable substrates. In contrast, cells disrupted by a French press or by lysozyme oxidize these substrates at pH 7.2 and without NH(4) (+). Moreover, the alkaline pH and NH(4) (+) inhibit substrate oxidation by the broken cells. These striking differences between whole and disrupted cells suggest that pH and NH(4) (+) affect whole cells externally and not internally. It appears that the alkaline pH is needed to convert NH(4) (+) to free NH(3). The latter in turn is required by the cells for the transport of low concentrations of substrate across the cell membrane. At high concentrations (20 to 250 mum), substrates force entry into the cells by simple diffusion, thereby eliminating the need for a high pH and NH(4) (+) for oxidation.
...
PMID:EFFECT OF PH AND AMMONIUM IONS ON THE PERMEABILITY OF BACILLUS PASTEURII. 1408 82

The trypsinized cell walls of Group C streptococci contain two components, the group-specific carbohydrate and a mucopeptide polymer. Hot formamide extraction of Group C cell walls results in a soluble group-specific carbohydrate fraction and an insoluble mucopeptide residue. This mucopeptide, similar in composition to that of Groups A and A-variant streptococci, contains N-acetylglucosamine, N-acetylmuramic acid, alanine, glutamic acid, lysine, and glycine. It is dissolved by the muralytic enzymes, including lysozyme, which does not attack the whole cell wall. Lysis of the cell wall by phage-associated lysin results in the release of soluble fragments composed of the elements of mucopeptide. Group C carbohydrate extracted with formamide is composed primarily of N-acetylgalactosamine and rhamnose. Serological studies suggest that the specificity of Group C carbohydrate is determined by the N-acetylgalactosamine.
...
PMID:Studies on the chemical structure of the streptococcal cell wall. II. The composition of group C cell walls and chemical basis for serologic specificity of the carbohydrate moiety. 1445 33

The cell walls of an 80/81 strain of Staphylococcus aureus (NYH-6) contain alanine, glycine, glutamic acid, lysine, muramic acid, glucosamine, and ribitol phosphate. 94 per cent of the phosphorus and 41 per cent of the glucosamine are removed by extraction of the cell walls with hot 5 per cent TCA, but significant amounts of the other constituents are not extracted by this procedure. The residue after hot TCA extraction (mucopeptide) is susceptible to lysozyme whereas the intact cell walls are resistant. Staphylococcus aureus cell walls are agglutinated by S. aureus antisera. Agglutination of the cell walls of one S. aureus strain is inhibited by absorption of antisera with cell walls of other S. aureus strains but not by absorption with S. albus cell walls. The ribitol teichoic acid can be isolated from cold TCA extracts of the cell walls. This compound consists almost entirely of ribitol phosphate and glucosamine. The isolated teichoic acid of strain NYH-6 is readily fixed to tanned sheep erythrocytes and these sensitized cells are agglutinated by S. aureus antisera. Cold TCA extracts of cell walls of other strains of S. aureus inhibit hemagglutination whereas extracts of S. albus walls do not. Studies on the inhibition of both hemagglutination and precipitation indicate that the antigenic determinant of S. aureus NYH-6 teichoic acid is beta-N-acetylglucosamine.
...
PMID:Studies on the chemistry and immunochemistry of cell walls of Staphylococcus aureus. 1447 45

The role of glutamate as osmoprotector was investigated through the study of a mutation in its biosynthetic pathway. A glt::Tn917-lacZ-cat insertion mutant (N1) conferring glutamate auxotrophy and enhanced beta-galactosidase expression on high-salt media was selected. Co-transformation experiments and PCR analysis allowed locating the insertion into the gltB gene corresponding to the small unit of the glutamate synthase (GOGAT). The N1 mutant strain presented a glutamate requirement for growth and a tenfold decrease in GOGAT activity. Transcriptional activity of GOGAT, measured as beta-galactosidase from the transposon fusion, correlated with enzymatic activity; expression was enhanced at the stationary phase and in high-ionic-strength media. However, osmotolerance of cultures of N1 mutant were as wild-type (wt), at least in semi-rich medium. In contrast, sporulation was slightly reduced (75% of wt), and spores were less resistant to UV, heat, and osmolarity, properties linked to the content of small, acid-soluble proteins (SASP). The content of these proteins was, in fact, reduced, in particular the SASP-gamma type. The peptidoglycan-cortex, however, was not impaired since spores maintained lysozyme resistance. Addition of glutamate during sporulation partially rescued spore resistance, but germination and outgrowth remained impaired. Deficiencies in germination and outgrowth were also observed with spores from a gltA mutant strain. Taken together, these results pointed to the importance of GOGAT activity during sporulation, in particular for the synthesis SASPs.
...
PMID:Effect of glutamate synthase (GOGAT) activity on Bacillus subtilis spore properties. 1457 Feb 71

Bulgecin A, a bacterial metabolite, has been shown to bind in the active-site groove of the chicken-type lysozyme from the rainbow trout (RBTL) and in the lysozyme-like C-terminal domain, of a soluble lytic transglycosylase (C-SLT) from Escherichia coli. These enzymes are muramidases that cleave the glycosidic bonds in the glycan strands of the murein polymer. Here we report the crystal structure of a complex between the goose-type lysozyme from the egg white of the Australian black swan (SEWL) and bulgecin A at 2.45 A resolution. As is the case for the C-SLT/bulgecin and RBTL/bulgecin complexes, the ligand binds with the N-acetylglucosamine ring in subsite C and the proline moiety in site D where it interacts with the catalytic glutamic acid. The taurine residue interacts with the beta-sheet region. Comparisons of the three buigecin complexes show that the inhibitor has the same binding mode to the muramidases with similar protein-ligand interactions, particularly for SEWL and RBTL. From our results, it seems likely that bulgecin, in general, inhibits enzymes with lysozyme-like domains and thus might represent a novel class of natural antibiotics that act on murein-degrading rather than murein-synthesizing enzymes.
...
PMID:Structure of a bulgecin-inhibited g-type lysozyme from the egg white of the Australian black swan. A comparison of the binding of bulgecin to three muramidases. 1529 31

Syringacin 4-A, a bacteriocin produced by Pseudomonas syrinagae 4-A, was obtained by induction with ultraviolet irradiation or mitomycin C. Approximately 1,000-fold purification of the bacteriocin was achieved by manganous chloride precipitation, differential centrifugation, and chromatography on hydroxyapatite columns. The purified syngacin was homogeneous on hydroxyapatite columns and sucrose density gradients; it also sedimented as a single entity in the analytical ultracentrifuge. The buoyant density of purified syringacin in cesium chloride was 1.294 g/ml. The sedimentation coefficient was calculated as 120S, and the diffusion coefficient was 6.49 x 10(-8) cm(2)/s. The molecular weight was calculated as 1.6 x 10(7) from physical data and 1.7 x 10(7) from biological data. The syringacin was composed of about 88.4% protein, 8.5% arabinose, 2.2% galacturonic acid, and 0.7% glucosamine. Amino acid analysis indicated a predominance of leucine (12.1%), aspartic acid (12.2%), and glutamic acid (12.7%). The ultraviolet spectrum showed a maximum absorbance peak at 276 nm. The syringacin was heat and alcohol sensitive, but resistant to trypsin, chymotrypsin, carboxypeptidase, Pronase, protease, lysozyme, steapsin, deoxyribonuclease, and ribonuclease. Maximum pH stability was between 5 and 8. Crude bacteriocin was stable at room temperature for at least a year, and purified material was stable for at least 3 months at 4 C.
...
PMID:Purification and characterization of syringacin 4-A, a bacteriocin from pseudomonas syringae 4-A. 1582 74

Protein self-interaction is important in protein crystal growth, solubilization, and aggregation, both in vitro and in vivo, as with protein misfolding diseases, such as Alzheimer's. Although second virial coefficient studies can supply invaluable quantitative information, their emergence as a systematic approach to evaluating protein self-interaction has been slowed by the limitations of traditional measurement methods, such as static light scattering. Comparatively, self-interaction chromatography is an inexpensive, high-throughput method of evaluating the osmotic second virial coefficient (B) of proteins in solution. In this work, we used self-interaction chromatography to measure B of lysozyme in the presence of various cosolvents, including sucrose, trehalose, mannitol, glycine, arginine, and combinations of arginine and glutamic acid and arginine and sucrose in an effort to develop a better fundamental understanding of protein self-interaction in complex cosolvent systems. All of these cosolvents, alone or in combination, increased B, indicating a reduction in intermolecular attraction. However, the magnitude of cosolvent-induced changes in B was found to be largely dependent on the ability to control long-range electrostatic repulsion. To the best of our knowledge, this work represents the most comprehensive virial coefficient study to date focusing on complex cosolvent-induced effects on the self-interaction of lysozyme.
...
PMID:Second virial coefficient studies of cosolvent-induced protein self-interaction. 1619 99

The release of dipicolinic acid (DPA) during the germination of Bacillus subtilis spores by the cationic surfactant dodecylamine exhibited a pH optimum of approximately 9 and a temperature optimum of 60 degrees C. DPA release during dodecylamine germination of B. subtilis spores with fourfold-elevated levels of the SpoVA proteins that have been suggested to be involved in the release of DPA during nutrient germination was about fourfold faster than DPA release during dodecylamine germination of wild-type spores and was inhibited by HgCl(2). Spores carrying temperature-sensitive mutants in the spoVA operon were also temperature sensitive in DPA release during dodecylamine germination as well as in lysozyme germination of decoated spores. In addition to DPA, dodecylamine triggered the release of amounts of Ca(2+) almost equivalent to those of DPA, and at least one other abundant spore small molecule, glutamic acid, was released in parallel with Ca(2+) and DPA. These data indicate that (i) dodecylamine triggers spore germination by opening a channel in the inner membrane for Ca(2+)-DPA and other small molecules, (ii) this channel is composed at least in part of proteins, and (iii) SpoVA proteins are involved in the release of Ca(2+)-DPA and other small molecules during spore germination, perhaps by being a part of a channel in the spore's inner membrane.
...
PMID:Role of SpoVA proteins in release of dipicolinic acid during germination of Bacillus subtilis spores triggered by dodecylamine or lysozyme. 1715 59


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