Thrombin-induced platelet microbicidal protein (tPMP) is a small, cationic, antimicrobial peptide released from rabbit platelets when stimulated with thrombin. We studied the relationship between staphylococcal transmembrane potential (delta psi) and tPMP staphylocidal activity. A genetically related pair of Staphylococcus aureus strains, 6850 and JB1, which differ in delta psi generation (-143 and -97 mV, respectively) were used. Mutant JB-1 was substantially less susceptible to tPMP than the parental strain, 6850. Menadione supplementation, which normalized the delta psi of strain JB-1, did not restore JB-1 tPMP susceptibility. These findings suggest that the staphylocidal activities of tPMP require factors other than or in addition to an intact delta psi.
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http://dx.doi.org/10.1128/iai.64.3.1070-1074.1996 | DOI Listing |
Int J Biol Macromol
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G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 100 Let Vladivostoku Prosp., 159, 690022 Vladivostok, Russian Federation.
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Department of Neurobiology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
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View Article and Find Full Text PDFBMC Genomics
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College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, 266109, China.
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View Article and Find Full Text PDFSci Rep
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View Article and Find Full Text PDFRSC Adv
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