Characterization of classic type II restriction-modification systems (RMS) (restriction endonucleases and modification methyltransferases) was carried out in isolates of Staphylococcus aureus and Streptococcus agalactiae obtained from clinical material. Among the 100 isolates of S. aureus two different RMS type II were detected. The first was expressed in isolates 32 and 33 (Sau32 I and Sau33 I); the targeting sequence was determined as 5'-GGN CC-3' (Sau96 I isoschizomer). The second was found in isolates no. 90, 93, 96*, and 98 (Sau90 I, Sau93 I, Sau96* I, Sau98 I) and enzymes recognized sequence 5'-CTY RAG-3' (SmlI isoschizomer). Analysis of 40 isolates of S. agalactiae revealed only one RMS; it was detected in two isolates (no. 16 and 23; Sag16 I and Sag23 I). Restriction endonuclease expressed by these isolates cleaved DNA in sequence 5'-CTG CA/G-3' (PstI isoschizomer). In RMS-positive S. aureus and S. agalactiae isolates plasmid DNA capable of replication in Escherichia coli and Bacillus subtilis was also detected and isolated.

• MeSH
• DNA, Bacterial metabolism   MeSH
• DNA Restriction-Modification Enzymes genetics   metabolism   MeSH
• Animals, Domestic MeSH
• Deoxyribonucleases, Type II Site-Specific genetics   metabolism   MeSH
• Staphylococcal Infections microbiology   veterinary   MeSH
• Staphylococcus aureus enzymology   isolation & purification   MeSH
• Streptococcus agalactiae enzymology   isolation & purification   MeSH
• Streptococcal Infections microbiology   veterinary   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• DNA, Bacterial MeSH
• DNA Restriction-Modification Enzymes MeSH
• Deoxyribonucleases, Type II Site-Specific MeSH

An open reading frame homologous to the genes encoding several cell-wall hydrolyzing enzymes was identified on the genome of actinophage mu 1/6. This open reading frame encoding the putative endolysin was amplified by polymerase chain reaction and cloned into the expression vector pET-21a. This gene consisted of 1182 bp encoding a 393 amino acid polypeptide with a molar mass of 42.1 kDa. The gene product was overexpressed in Escherichia coli, and then the lytic enzyme was purified by a two-step chromatographic procedure. When applied exogenously, the endolysin of phage mu 1/6 was active against all tested Streptomyces strains but did not affect other bacteria. The amino acid sequence showed a high homology with a putative amidase of the Streptomyces phase phi C31. Downstream of the endolysin gene, an open reading frame encoding an 88 amino acid protein was identified. Structural analysis of its sequence revealed features characteristics for holin.

• MeSH
• Bacteriophage mu enzymology   genetics   MeSH
• Cell Wall metabolism   MeSH
• Endopeptidases genetics   isolation & purification   metabolism   MeSH
• Hydrolysis MeSH
• Cloning, Molecular MeSH
• Hydrogen-Ion Concentration MeSH
• Molecular Sequence Data MeSH
• Gene Expression Regulation, Viral MeSH
• Gene Expression Regulation, Enzymologic MeSH
• Amino Acid Sequence MeSH
• Streptomyces aureofaciens virology   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• endolysin MeSH Browser
• Endopeptidases MeSH