Evers S, Reynolds P E, Courvalin P
Unité des Agents Antibactériens, Centre National de la Recherche Scientifique EP J0058, Institut Pasteur, Paris, France.
Gene. 1994 Mar 11;140(1):97-102. doi: 10.1016/0378-1119(94)90737-4.
A pair of degenerate oligodeoxyribonucleotides was used to amplify, by the polymerase chain reaction (PCR), DNA fragments internal to genes encoding D-Ala:D-Ala ligase-related proteins of vancomycin-resistant (VmR) Enterococcus faecalis V583. Cloning and nucleotide sequencing of the PCR products indicated that fragments of two genes, designated vanB and ddl, were co-amplified. The vanB gene was previously shown to be present in Enterococcus strains expressing VanB-type VmR [Quintiliani Jr. et al., J. Infect. Dis. 8 (1993) 943-950]. The ddl gene was detected by Southern hybridization in all VmR and VmS strains of En. faecalis, but not in representatives of 17 other species of Enterococcus. The vanB and ddl genes were cloned in bacteriophage lambda and sequenced. There was extensive similarity (76% amino-acid identity) between the product of vanB and the VmR protein, VanA. The product of ddl, the D-Ala:D-Ala ligases, DdlA and DdlB, of Escherichia coli and the resistance proteins, VanA and VanB, were more distantly related (32-40% aa identity). After induction of VmR, En. faecalis V583 synthesized the cell wall precursor, UDP-N-acetylmuramyl-tetrapeptide-D-lactate, indicating that the mechanism of glycopeptide resistance in strains with the VanA and VanB phenotype is similar.
使用一对简并寡脱氧核糖核苷酸，通过聚合酶链反应（PCR）扩增耐万古霉素（VmR）粪肠球菌V583中编码D - 丙氨酸：D - 丙氨酸连接酶相关蛋白的基因内部的DNA片段。PCR产物的克隆和核苷酸测序表明，两个基因片段（命名为vanB和ddl）被共同扩增。先前已证明vanB基因存在于表达VanB型VmR的肠球菌菌株中[Quintiliani Jr.等人，《传染病杂志》8（1993）943 - 950]。通过Southern杂交在所有粪肠球菌的VmR和VmS菌株中检测到ddl基因，但在其他17种肠球菌的代表菌株中未检测到。将vanB和ddl基因克隆到噬菌体λ中并进行测序。vanB的产物与VmR蛋白VanA之间存在广泛的相似性（氨基酸同一性为76%）。ddl的产物、大肠杆菌的D - 丙氨酸：D - 丙氨酸连接酶DdlA和DdlB与抗性蛋白VanA和VanB的关系更远（氨基酸同一性为32 - 40%）。诱导VmR后，粪肠球菌V583合成细胞壁前体UDP - N - 乙酰胞壁酰 - 四肽 - D - 乳酸，表明具有VanA和VanB表型的菌株中糖肽抗性机制相似。
