Smith M C, Murray B E
Center for Infectious Diseases, University of Texas Medical School, Houston 77030.
Antimicrob Agents Chemother. 1992 Oct;36(10):2265-9. doi: 10.1128/AAC.36.10.2265.
The putative beta-lactamase (Bla) repressor gene, blaI, from the staphylococcal plasmid pI524 was isolated, and the DNA sequence was determined. The sequence of blaI was found to be identical to the blaI sequence from pI9789 (blaI blaZ seg-1), a plasmid related to pI524. A blaI probe from pI524 was hybridized with plasmid and genomic DNA from Bla+ Enterococcus faecalis isolates HH22 and PA. The Bla structural gene of HH22 has been previously shown to be of staphylococcal origin, but DNA homologous to the staphylococcal Bla repressor was not found, indicating that the constitutive production of beta-lactamase in these E. faecalis isolates may be the result of a missing repressor protein.
从葡萄球菌质粒pI524中分离出假定的β-内酰胺酶(Bla)阻遏基因blaI,并测定了其DNA序列。发现blaI的序列与来自pI9789(blaI blaZ seg-1)的blaI序列相同,pI9789是一种与pI524相关的质粒。来自pI524的blaI探针与Bla+粪肠球菌分离株HH22和PA的质粒及基因组DNA进行杂交。先前已表明HH22的Bla结构基因源自葡萄球菌,但未发现与葡萄球菌Bla阻遏物同源的DNA,这表明这些粪肠球菌分离株中β-内酰胺酶的组成型产生可能是由于阻遏蛋白缺失所致。