The relationship between outer membrane protein D_2 of Pseudomonas aeruginosa and imipenem resistance / 中国感染与化疗杂志

ABSTRACT

Objective To prepare specific polyclonal antibodies to outer membrane protein (Opr) D_2 of Pseudomonas aeruginosa (PA),and explore the relationship between loss of OprD_2 and imipenem resistance.Methods The genomic DNA of PA was ex- tracted with phenolchloroform.OprD_2 coding gene was amplified by PCR and prokaryotic expression vector pRSET-OprD_2 was constructed.OprD_2 protein was expressed by IPTG induction in E.coli BL21(DE3),and purified with SDS-PAGE.The new protein band was recovered and used as antigens to subcutaneously immunize two New Zealand rabbits to prepare poly- clonal antibody.The specificity of the antibody was determined by Western blot.The expression of OprD_2 in 32 clinical isolates of PA was detected with the prepared polyclonal antibody by Western blot.Results The vector pRSET-OprD_2 has been success- fully expressed in E.coli BL21 (DE3).The polyclonal anti-OprD_2 antibody with high specificity has been successfully pre- pared.Present results show that of the 27 imipenem-resistant PA clinical isolates,OprD2 protein was low-expressed in 5 iso- lates (18.5%) and normally expressed in 2 isolates (7.4%) but not expressed in 20 isolates (74.1%).Conclusions The loss or low-expression of OprD_2 is one of the essential mechanisms accounting for imipenem resistance in clinical isolates of PA.