tailieunhanh - Báo cáo khoa học: The metalloprotease PrtV from Vibrio cholerae Purification and properties

TheVibriometalloprotease PrtV was purified from the culture supernatant of aVibrio choleraederivative that is deficient in several other secreted pep-tidases, including the otherwise abundant hemagglutinin⁄protease HapA. The PrtV is synthesized as a 102 kDa protein, but undergoes several N- and C-terminal processing steps duringV. choleraeenvelope transloca-tion and prolonged incubation. | ỊFEBS Journal The metalloprotease PrtV from Vibrio cholerae Purification and properties Karolis Vaitkevicius Pramod K. Rompikuntal Barbro Lindmark Rimas Vaitkevicius Tianyan Song and Sun N. Wai Department of Molecular Biology Umea University Sweden QnlineGpen Thisarticleis available free online at Keywords characterization metalloprotease PrtV purification V. choleras Correspondence S. N. Wai Department of Molecular Biology Umea University S 90187 Umea Sweden Fax 46 90 772630 Tel 46 90 7856704 E-mail Re-use of this article is permitted in accordance with the Creative Commons Deed Attribution which does not permit commercial exploitation Received 24 November 2007 revised 22 March 2008 accepted 16 April2008 The Vibrio metalloprotease PrtV was purified from the culture supernatant of a Vibrio cholerae derivative that is deficient in several other secreted peptidases including the otherwise abundant hemagglutinin protease HapA. The PrtV is synthesized as a 102 kDa protein but undergoes several N- and C-terminal processing steps during V. cholerae envelope translocation and prolonged incubation. Purified V. cholerae PrtV protease forms of 81 or 73 kDa were stabilized by calcium ions. Removal of calcium resulted in further rapid autoproteolysis. The two major products of autoproteolysis of the PrtV protease were approximately 37 and 18 kDa and could not be separated under non-denaturing conditions indicating they are interacting domains. In an assay using cultured cells of the human intestinal cell line HCT8 the PrtV protein showed a cytotoxic effect leading to cell death. Using human blood plasma as a source of potential substrates of mammalian origin for the PrtV protease we found that the extracellular matrix components fibronectin and fibrinogen were degraded by the enzyme. Additional tests with individual protein substrates revealed that plasminogen was also a possible target for the PrtV protease. doi .