Tissue factor pathway inhibitor 2 is found in skin and its C-terminal region encodes for antibacterial activity.
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ABSTRACT: Background
Tissue factor pathway inhibitor 2 (TFPI-2) is a matrix-associated serine protease inhibitor with an enigmatic function in vivo. Here, we describe that TFPI-2 is present in fibrin of wounds and also expressed in skin, where it is up-regulated upon wounding.Methodology and principal findings
Neutrophil elastase cleaved TFPI-2, and a C-terminal fragment was found to bind to bacteria. Similarly, a prototypic peptide representing this C-terminal part, EDC34, bound to bacteria and bacterial lipopolysaccharide, and induced bacterial permeabilization. The peptide also induced leakage in artificial liposomes, and displayed a random coil conformation upon interactions with liposomes as well as lipopolysaccharide. EDC34 was antibacterial against both Gram-negative and Gram-positive bacteria in physiological buffer conditions.Conclusions/significance
The results demonstrate that the C-terminus of TFPI-2 encodes for antimicrobial activity, and may be released during wounding.
SUBMITTER: Papareddy P
PROVIDER: S-EPMC3530512 | biostudies-literature | 2012
REPOSITORIES: biostudies-literature
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