Allignet J, Loncle V, Simenel C, Delepierre M, el Solh N
National Reference Center for Staphylococci, Laboratoire des Staphylocoques et des Streptocoques, Nucléaire-Institut Pasteur, Paris, France.
Gene. 1993 Aug 16;130(1):91-8. doi: 10.1016/0378-1119(93)90350-c.
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. Resistance to A-type compounds of Vml antibiotics conferred to S. aureus by vat was not expressed in E. coli, although a protein having a M(r) similar to that encoded by this gene was detected in E. coli minicells. The vat gene was detected by the polymerase chain reaction in two chromosomally located staphylococcal conjugative elements and in the conjugative plasmid, pIP1156, conferring resistance to A-type compounds.
金黄色葡萄球菌质粒pIP680和pIP1156可赋予对维吉尼亚霉素样抗生素（Vml：链阳菌素A、原始霉素IIA、维吉尼亚霉素M）的A型化合物以及Vml抗生素A、B型化合物协同混合物的抗性，研究表明它们可通过乙酰化作用对A型化合物进行修饰。从质粒pIP680中分离并测序了编码修饰A型化合物的乙酰转移酶的vat基因。该基因可能编码一种219个氨基酸（aa）的蛋白质VAT，分子量为24330 Da，与从大肠杆菌和根癌土壤杆菌中分离的cat基因编码的两种氯霉素乙酰转移酶具有至少38%的氨基酸同一性。尽管在大肠杆菌小细胞中检测到一种分子量与该基因编码的蛋白质相似的蛋白质，但vat赋予金黄色葡萄球菌对Vml抗生素A型化合物的抗性在大肠杆菌中并未表达。通过聚合酶链反应在两个位于染色体上的葡萄球菌接合元件以及赋予对A型化合物抗性的接合质粒pIP1156中检测到了vat基因。
