Sanschagrin F, Couture F, Levesque R C
Département de Microbiologie, Faculté de Médecine, Université Laval, Ste-Foy, Québec, Canada.
Antimicrob Agents Chemother. 1995 Apr;39(4):887-93. doi: 10.1128/AAC.39.4.887.
We determined the nucleotide sequence of the blaOXA-3(pMG25) gene from Pseudomonas aeruginosa. The bla structural gene encoded a protein of 275 amino acids representing one monomer of 31,879 Da for the OXA-3 enzyme. Comparisons between the OXA-3 nucleotide and amino acid sequences and those of class A, B, C, and D beta-lactamases were performed. An alignment of the eight known class D beta-lactamases including OXA-3 demonstrated the presence of conserved amino acids. In addition, conserved motifs composed of identical amino acids typical of penicillin-recognizing proteins and specific class D motifs were identified. These conserved motifs were considered for possible roles in the structure and function of oxacillinases. On the basis of the alignment and identity scores, a dendrogram was constructed. The phylogenetic data obtained revealed five groups of class D beta-lactamases with large evolutionary distances between each group.
我们测定了铜绿假单胞菌中blaOXA - 3(pMG25)基因的核苷酸序列。bla结构基因编码一种由275个氨基酸组成的蛋白质，代表OXA - 3酶的一个31,879 Da的单体。对OXA - 3核苷酸和氨基酸序列与A、B、C和D类β-内酰胺酶的序列进行了比较。包括OXA - 3在内的八种已知D类β-内酰胺酶的比对显示存在保守氨基酸。此外，还鉴定出了由青霉素识别蛋白典型的相同氨基酸组成的保守基序以及特定的D类基序。这些保守基序被认为可能在氧青霉烯酶的结构和功能中发挥作用。基于比对和同一性得分构建了一个系统发育树。获得的系统发育数据揭示了D类β-内酰胺酶的五组，每组之间有很大的进化距离。
