Sequence of a staphylococcal gene, vat, encoding an acetyltransferase inactivating the A-type compounds of virginiamycin-like antibiotics.

The Staphylococcus aureus plasmids, pIP680 and pIP1156, which confer resistance to A-type compounds of virginiamycin-like antibiotics (Vml: streptogramin A, pristinamycin IIA, virginiamycin M) and to synergistic mixtures of the A and B compounds of Vml antibiotics, were shown to direct the modification of A-type compounds by acetylation. The vat gene, encoding the acetyltransferase modifying A-type compounds, was isolated from plasmid pIP680 and sequenced. This gene potentially encodes a 219-amino-acid (aa) protein, VAT, of 24 330 Da showing at least 38% aa identity with two chloramphenicol acetyltransferases encoded by cat genes isolated from Escherichia coli and Agrobacterium tumefaciens.

Staphylococcus pasteuri sp. nov., isolated from human, animal, and food specimens.

A new novobiocin-susceptible species of the genus Staphylococcus, Staphylococcus pasteuri, is described on the basis of the results of a study of seven strains isolated from human, animal, and food specimens. DNA relatedness experiments (S1 nuclease method) showed that these strains form a homogeneous genomic species related at DNA homology levels of 2 to 13% to 27 type strains representing known Staphylococcus species. The use of a method based on rRNA gene restriction site polymorphism provides clear-cut distinction between this new species and Staphylococcus warneri, which is the most similar species phenotypically.

Multiple copies of IS256 in staphylococci.

EcoRI-digested cellular DNAs of 150 staphylococcal clinical isolates were probed with a plasmid containing a DNA piece from within the open reading frame of IS256. Most of the Gmr staphylococcal isolates tested contained more copies of IS256 than those associated with Tn4001 carried by these isolates. Three distinct copies of IS256 together with their flanking DNA were isolated by cloning from an EcoRI digest of the cellular DNA of the Gmr isolate, BM3121.

Sequence of a staphylococcal plasmid gene, vga, encoding a putative ATP-binding protein involved in resistance to virginiamycin A-like antibiotics.

The Staphylococcus aureus plasmid gene, vga, conferring resistance to A compounds of virginiamycin-like antibiotics (streptogramin A, pristinamycin II, virginiamycin M), and to synergistic mixtures of the A and B compounds of these antibiotics, was cloned and sequenced. This gene potentially encodes a 522-amino acid protein, VgA, of 60,115 Da which exhibits significant homology with the ATP-binding domains of numerous proteins. VgA has two ATP-binding domains, containing each the A and the B motifs, but does not contain long hydrophobic stretches that might represent potential membrane-spanning domains.

Usefulness of three probes in typing isolates of methicillin-resistant Staphylococcus aureus (MRSA).

Fifty-nine epidemiologically unrelated methicillin-resistant Staphylococcus aureus (MRSA) isolates from different geographical areas and 23 phage-type 77 MRSA isolates from France were investigated. Cellular DNA, digested with restriction endonucleases EcoRI or HindIII, was probed with plasmids carrying the gene encoding 16S rRNA (pBA2), the gene aacA-aphD (pSF815A) and the gene aacA-aphD plus part of IS256 (pIP1307). When probed with pBA2, most of the unrelated isolates displayed the same hybridisation pattern.