Influence of substrate modification and C-terminal truncation on the active site structure of substrate-bound heme oxygenase from Neisseriae meningitidis. A 1H NMR study.

ABSTRACT: Heme oxygenase (HO), from the pathogenic bacterium N. meningitidis(NmHO), which secures host iron, shares many properties with mammalian HOs but also exhibits some key differences. The crystal structure appears more compact, and the crystal-undetected C-terminus interacts with substrate in solution. The unique nature of substrate-protein, specifically pyrrole-I/II-helix-2, peripheral interactions in NmHO are probed by 2D (1)H NMR to reveal unique structural features controlling substrate orientation. The thermodynamics of substrate orientational isomerism are mapped for substrates with individual vinyl → methyl → hydrogen substitutions and with enzyme C-terminal deletions. NmHO exhibits significantly stronger orientational preference, reflecting much stronger and selective pyrrole-I/II int

SUBMITTER: Peng D 

PROVIDER: S-EPMC3250371 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature