Structure of the native cysteine-sulfenic acid redox center of enterococcal NADH peroxidase refined at 2.8 A resolution.

摘要: In order to obtain the crystal structure of flavoprotein NADH peroxidase with its native Cys42-sulfenic acid redox center, a strategy combining reduced exposure crystals ambient oxygen and data collection at −160 °C was applied. The enzyme 2.8 A resolution is described; these results conclusively establish existence as functional non-flavin center provide first for any naturally occurring protein-sulfenic acid. atoms Cα−Cβ−Sγ−O roughly define planar arrangement which stacked parallel si face FAD isoalloxazine positions sulfenyl atom only 3.3 from FAD-C4A. His10-Ne2 contributes hydrogen bond sulfenic oxygen, distance 3.2 A. Although one (OX1) non-native Cys42-sulfonic derivative identified in earlier wild-type taken represent ox...