海洋假单胞菌MR1菌株质粒pMR1汞抗性基因在大肠杆菌中的克隆与表达。

Cloning and expression of the mercury resistance genes of marine Pseudomonas sp. strain MR1 plasmid pMR1 in Escherichia coli.

作者信息

Rani D B, Mahadevan A

机构信息

Centre for Advanced Study in Botany, University of Madras, India.

出版信息

Res Microbiol. 1994 Feb;145(2):121-7. doi: 10.1016/0923-2508(94)90005-1.

DOI:10.1016/0923-2508(94)90005-1

PMID:8090992

Abstract

The mercury resistance determinant of marine Pseudomonas sp. strain MR1 plasmid pMR1 was cloned into a narrow-host-range vector pUC18. A direct selection of mercury resistant clones was successful and 12 clones were evolved; 9 from direct selection on mercury agar plates and 3 from ampicillin-resistant white colonies. All the predicted clones efficiently volatilized mercury. One of the hybrid plasmids pMRD5, containing a 15.5-kb insert, conferred inducible resistance to both HgCl2 and phenyl mercury acetate with over a 40-fold increase in mer resistance in Escherichia coli HB101. No DNA homology existed between the mer operon of Pseudomonas sp. strain MR1 and the characterized determinants of Tn501 mer DNA.

摘要

海洋假单胞菌属MR1菌株质粒pMR1的汞抗性决定簇被克隆到窄宿主范围载体pUC18中。直接筛选汞抗性克隆获得成功，共得到12个克隆；9个来自在汞琼脂平板上的直接筛选，3个来自氨苄青霉素抗性白色菌落。所有预测的克隆都能有效地挥发汞。其中一个含有15.5 kb插入片段的杂交质粒pMRD5，赋予大肠杆菌HB101对HgCl2和苯基醋酸汞诱导抗性，汞抗性增加了40多倍。假单胞菌属MR1菌株的mer操纵子与已鉴定的Tn501 mer DNA决定簇之间不存在DNA同源性。