Protein D2 porin of the Pseudomonas aeruginosa outer membrane bears the protease activity

FEBS Letters

Gotoh, Naomasa²  Nakae, Taiji¹  Yoshihara, Eisaku¹  Nishino, Takeshi² 

[1] Department of Molecular Life Science, Tokai University School of Medicine, Isehara 259-11, Japan;Department of Microbiology, Kyoto Pharmaceutical University, Yamashina, Kyoto 607, Japan

关键词: Protein D2;    Protease;    Pseudomonas aeruginosa;   

DOI  :  10.1016/0014-5793(96)00945-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We report here our discovery that protein D2 of the outer membrane of Pseudomonas aeruginosa is a novel porin bearing protease activity. Homogeneously purified protein D2 hydrolyzed several synthetic peptides according to the Michaelis-Menten kinetics. A specific serine protease inhibitor, diisopropyl fluorophosphate (DFP), inactivated the protease activity and [³H]DFP covalently labeled protein D2. We tested the effect of two monoclonal antibodies raised against protein D2 on the protease activity. One antibody lowered the protease activity to about 20%, while the other enhanced it to about 300% of that without antibody. In addition, the fractions derived from the outer membrane of the protein D2-deficient mutants showed negligible protease activity, whereas similarly fractionated outer membrane proteins of the protein D2-positive parent strain showed strong protease activity.

【 授权许可】

Unknown