Elsevier on behalf of the Federation of European Biochemical Societies
FEBS Letters vol:580 issue:26 pages:6206-6210
We investigated parabutoporin (PP), an antimicrobial scorpion peptide, to understand its inhibition on NADPH oxidase in human PMN. We show that PP is a good substrate for all PKC-isotypes, implicated in the activation of NADPH oxidase, and acts as a potent competitive inhibitor of in vitro p47(phox)-phosphorylation by PKC-alpha, -beta I, -beta II and -delta, but not PKC-sigma. In PMN, PP also inhibits the PMA-stimulated phosphorylation of p47(phox) and its subsequent translocation. In contrast, PP affects the PKC-independent activation to a much lesser degree. This indicates that PP inhibits the activation of NADPH oxidase at submicromolar concentrations in a strongly PKC-dependent manner. (c) 2006 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.