Return to Proteomics Alert Section
Reports outline protease study results from Chosun University
December 17th, 2007
2007 DEC 17 -- According to recent research published in the Journal of Bacteriology, "Vibrio vulnificus, a marine bacterium capable of causing wound infection and septicemia, secretes a 45-kDa metalloprotease (vEP) with many biological activities. The precursor of vEP consists of four regions: a signal peptide, an N-terminal propeptide (nPP), a C-terminal propeptide, and the mature protease." "Two forms of vEP-vEP-45, which contains the mature protease plus the C-terminal propeptide, and vEP-34, which contains only the mature protease-were expressed in Escherichia coli and purified. vEP-45 and vEP-34 had similar activities with azocasein as a substrate, but vEP-34 had reduced activity toward insoluble proteins. The nPP of vEP was expressed as a His tag fusion protein, and its effect on vEP activity was investigated. nPP inhibited the activities of both vEP-45 and vEP-34 but not that of thermolysin, a different but related zinc-dependent protease. The inhibition of vEP by nPP was further examined using vEP-34 as a representative enzyme. The inhibition could be completely reversed under conditions of low enzyme and propeptide concentrations and with prolonged incubation, which resulted from the degradation of nPP by vEP. However, even at high nPP and vEP concentrations, inhibition of vEP by nPP at high temperatures was not effective, resulting in the degradation of both nPP and vEP," wrote A.K. Chang and colleagues, Chosun University. The researchers concluded: "These results demonstrate that the nPP of vEP could bind to vEP and inhibit its activity, resulting in the degradation of the propeptide." Chang and colleagues published their study in the Journal of Bacteriology (The N-terminal propeptide of Vibrio vulnificus extracellular metalloprotease is both an inhibitor of and a substrate for the enzyme. Journal of Bacteriology, 2007;189(19):6832-6838). For additional information, contact J.S. Lee, Chosun University, College Nat Science, Dept. of Biotechnology, 375 Seosuk Dong, Kwangju 501759, South Korea. The publisher's contact information for the Journal of Bacteriology is: American Society Microbiology, 1752 N St. NW, Washington, DC 20036-2904, USA. Keywords: South Korea, Bacteriology, Enzyme Research, Enzymology, Escherichia coli, Metalloprotease, Peptide, Protease, Proteomics. Fusion Proteins, Septicemia, Vibrio, Wound Infection, Chosun University. This article was prepared by Proteomics Weekly editors from staff and other reports. Copyright 2007, Proteomics Weekly via NewsRx.com.
Return to Proteomics Alert Section
|
