화학공학소재연구정보센터
Biochemical and Biophysical Research Communications, Vol.405, No.3, 344-348, 2011
Crystal structure and site-directed mutagenesis of a nitroalkane oxidase from Streptomyces ansochromogenes
Nitroalkane oxidase (NAO) catalyzes neutral nitroalkanes to their corresponding aldehydes or ketones, hydrogen peroxide and nitrite. The crystal structure of NAO from Streptomyces ansochromogenes was determined; it consists of two domains, a TIM barrel domain bound to FMN and C-terminal domain with a novel folding pattern. Site-directed mutagenesis of His(179), which is spatially adjacent to FMN, resulted in the loss of enzyme activity, demonstrating that this amino acid residue is important for catalysis. The crystal structure of mutant H179D-nitroethane was also analyzed. Interestingly, Sa-NAO shows the typical function as nitroalkane oxidase but its structure is similar to that of 2-nitropropane dioxygenase. Overall, these results suggest that Sa-NAO is a novel nitroalkane oxidase with TIM barrel structure. (C) 2010 Elsevier Inc. All rights reserved.