Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.11 (CD10)
 9,792 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The glycylglycine endopeptidase in lysostaphin has been found capable of catalysing both hydrolysis and transpeptidation reactions when acting on glycyl peptides. The ability of the enzyme to utilize dansyldiglycine (5-dimethylaminoaphthalene-1-sulphonylglycylglycine) as an acceptor molecule in transpeptidation reactions, although it is incapable of hydrolysing the peptide bond in this compound, indicates the enzyme must be capable of forming the equivalent of an imino-enzyme intermediate during the catalytic process.
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PMID:Lysostaphin endopeptidase-catalysed transpeptidation reactions of the imino-transfer type. 58 62

Bacteriolytic enzymes of different bond specificities, denatured by sodium dodecyl sulphate (SDS), were electrophoresed in polyacrylamide gels containing bacterial cells, then renatured after removal of SDS by diffusion. Enzyme activity was seen in sharp transparent bands resulting from bacteriolysis in the gels, while these sections containing bacterial cells appeared cloudy. Bacteriolytic enzymes including staphylococcal endo-beta-N-acetylglucosaminidase, lysozyme (N-acetylmuramidase), and lysostaphin (endopeptidase) were detected. The major bacteriolytic enzymes of Staphylococcus spp. were identified in gels after electrophoresis of crude enzyme preparations. This demonstrates the wide applicability of this method to the study of staphylococcal bacteriolytic enzymes. However, it should be noted that the method will fail to detect activities of bacteriolytic enzymes which are irreversibly inhibited by SDS.
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PMID:Visualization of endo-beta-N-acetylglucosaminidase, lysozyme, and lysostaphin after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. 171 2

A derivative of Staphylococcus simulans biovar staphylolyticus cured of all five plasmids present in the wild-type organism was developed, and the characteristics of extracellular protein production by this plasmidless strain were compared to those of the wild type. Although staphylolytic endopeptidase (lysostaphin) and beta-lactamase are known to be plasmid encoded, analysis of this cured strain revealed that most other extracellular proteins are chromosomally encoded.
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PMID:Characteristics of extracellular protein production by a plasmidless derivative of Staphylococcus simulans biovar staphylolyticus. 176 50

Staphylococcus simulans biovar staphylolyticus, the lysostaphin-producing organism, contains five plasmids designated pACK1 through pACK5. Hybridization analysis using cloned beta-lactamase gene (bla) as probe and characterization of cured strains revealed that bla resides on pACK3 rather than on the lysostaphin endopeptidase plasmid (pACK1) as reported by others.
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PMID:Beta-lactamase is encoded on plasmid pACK3 in Staphylococcus simulans biovar staphylolyticus. 200 92

Staphylococcus simulans biovar staphylolyticus, the lysostaphin-producing organism, secretes a staphylolytic endopeptidase (EC 3.4.99.17) that is encoded on plasmid pACK1. Susceptibility of pACK1-cured strains to lysis by endopeptidase established that resistance to this enzyme is not an inherent property of the organism but rather is encoded on this dispensable plasmid. Furthermore, the enzyme is not an autolysin that is essential for cell wall synthesis because strains lacking the endopeptidase gene grew normally.
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PMID:Plasmid-encoded lysostaphin endopeptidase resistance of Staphylococcus simulans biovar staphylolyticus. 273 Jun 41

The ability of macromolecules to cross the capsular layer of encapsulated microorganisms and interact with their cell walls is important in considerations of the mechanisms of resistance to phagocytosis and of antigen masking in such strains. Lysostaphin was employed as a probe of the penetrability of the Staphylococcus aureus capsule. The rates of lysostaphin-induced lysis of encapsulated and unencapsulated S. aureus strains were compared. Encapsulated S. aureus strains M and Smith diffuse were lysed by lysostaphin at the same rate as their respective unencapsulated counterpart strains M variant and Smith compact. Growth of the M strain in a medium designed to enhance capsule production did not delay the onset or decrease the rate of lysis of the strain compared with organisms grown in normal medium. Cations did not selectively decrease the rate of lysis of the encapsulated strain, but inhibited the lysis of both the M and M variant strains. Peptidoglycan, the presumed lysostaphin target, isolated from both M and M variant strains was digested by lysostaphin at very similar rates. In contrast to whole cells, cations stimulated the rate of lysostaphin digestion of peptidoglycan. It is concluded that the fraction of lysostaphin active in cell lysis, believed to be a glycylglycine endopeptidase with a molecular weight of about 25,000, passes freely through the capsular layer to its target in the staphylococcal cell wall.
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PMID:Facile penetration of the Staphylococcus aureus capsule by lysostaphin. 742 37

Staphylococcus simulans biovar staphylolyticus produces an extracellular glycylglycine endopeptidase (lysostaphin) that lyses other staphylococci by hydrolyzing the cross bridges in their cell wall peptidoglycans. The genes for endopeptidase (end) and endopeptidase resistance (epr) reside on plasmid pACK1. An 8.4-kb fragment containing end was cloned into shuttle vector pL150 and was then introduced into Staphylococcus aureus RN4220. The recombinant S. aureus cells produced endopeptidase and were resistant to lysis by the enzyme, which indicated that the cloned fragment also contained epr. Treatments to remove accessory wall polymers (proteins, teichoic acids, and lipoteichoic acids) did not change the endopeptidase sensitivity of walls from strains of S. simulans biovar staphylolyticus or of S. aureus with and without epr. Immunological analyses of various wall fractions showed that there were epitopes associated with endopeptidase resistance and that these epitopes were found only on the peptidoglycans of epr+ strains of both species. Treatment of purified peptidoglycans with endopeptidase confirmed that resistance or susceptibility of both species was a property of the peptidoglycan itself. A comparison of the chemical compositions of these peptidoglycans revealed that cross bridges in the epr+ cells contained more serine and fewer glycine residues than those of cells without epr. The presence of the 8.4-kb fragment from pACK1 also increased the susceptibility of both species to methicillin.
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PMID:The lysostaphin endopeptidase resistance gene (epr) specifies modification of peptidoglycan cross bridges in Staphylococcus simulans and Staphylococcus aureus. 774 66

The present paper reports a modified method for isolation of lysostaphin--a bacteriolytic agent with specific affinity for staphylococcal cell wall. The proposed purification scheme includes three steps. The first procedure is ultrafiltration through a membrane filter giving a yield of 75.6%. The result of ultrafiltration is a concentrated, 10-times purified preparation of lysostaphin with specific activity 0.62 U/mg which can be used for digestion of S. aureus cells. Further step, performed by ion-exchange chromatography on DEAE-cellulose, yields a 60-times purified preparation containing a mixture of enzyme components of lysostaphin. The yield of this step is 47.2%, the preparation contains 3.54 U/mg protein. Using gel filtration on Sephadex G-50 a component with hexosaminidase activity was separated from the endopeptidase component on the basis of molar mass difference. A 270-times purified preparation of lysostaphin-endopeptidase with minimum of contaminating substances was obtained in this step. The yield of gel filtration was 22.1%, specific activity increased up to 16.3 U/mg protein.
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PMID:Modified simplified method for isolation of lysostaphin from the culture filtrate of Staphylococcus staphylolyticus. 836

A simple and efficient method for the purification of staphylolytic endopeptidase (lysostaphin) contained in culture supernatant of Staphylococcus simulans biovar staphylolyticus strain by adsorption of the enzyme on bacterial cells of lysostaphin-resistant S. aureus mutant was successfully devised. Lysostaphin was sufficiently absorbed on the heat-killed mutant cells derived from S. aureus Cowan I and efficiently eluted by 3 M KSCN. Enzyme preparation obtained by a single procedure of the affinity purification was pure enough for practical use. The yield of the enzyme was 25 mg from 1 liter culture and recovery rate was 64%.
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PMID:Efficient adsorption of lysostaphin on bacterial cells of lysostaphin-resistant Staphylococcus aureus mutant. 847 55

A novel staphylolytic enzyme, ALE-1, acting on Staphylococcus aureus, was purified from a Staphylococcus capitis EPK1 culture supernatant. The optimal pH range for staphylolytic activity was 7 to 9. ALE-1 contains one Zn2+ atom per molecule. Analysis of peptidoglycan fragments released by ALE-1 indicated that the enzyme is a glycylglycine endopeptidase. The effects of various modulators were determined, and we found that o-phenanthroline, iodoacetic acid, diethylpyrocarbonate, and Cu2+ reduced the staphylolytic activity of ALE-1. beta-Casein, elastin, and pentaglycine were poor substrates for ALE-1. Molecular cloning data revealed that ALE-1 is composed of 362 amino acid residues and is synthesized as a precursor protein which is cleaved after Ala at position 35, thus producing a mature ALE-1 of 35.6 kDa. The primary structure of mature ALE-1 is very similar to the proenzyme form of lysostaphin. It has the modular design of an N-terminal domain of tandem repeats of a 13-amino-acid sequence fused to the active site containing C-terminal domain. Unlike lysostaphin, ALE-1 does not undergo processing of the N-terminal repeat domain in broth culture. ale-1 is encoded on the plasmid. Protein homology search suggested that ALE-1 and lysostaphin are members of the novel Zn2+ protease family with a homologous 38-amino-acid-long motif, Tyr-X-His-X(11)-Val-X(12/20)-Gly-X(5-6)-His.
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PMID:Purification and molecular characterization of glycylglycine endopeptidase produced by Staphylococcus capitis EPK1. 902 2


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