| Abstract: | The major serum inhibitor of proteolytic activity, alpha-1-proteinase inhibitor (alpha-1-PI), (or alpha-1-antitrypsin) can be readily inactivated by oxidation [Carp, H. & Janoff, A. (1978) Am. Rev. Resp. Dis. 118, 617-621]. This inactivation appears to be due to the oxidation of a critical methionine(s) in alpha-1-PI that is required for the inhibition of elastase activity. An enzyme from Escherichia coli that reduces methionine sulfoxide residues in protein [Brot, N., Weissbach, L., Werth, J. & Weissbach, H. (1981) Proc. Natl. Acad. Sci. USA 78, 2155-2158] can restore the biological inhibitory activity of canine oxidized alpha-1-PI. |
