Crystallization and preliminary crystallographic analysis of an NADH oxidase that functions in peroxide reduction in Thermus aquaticus YT-1

NADH oxidase from Thermus aquaticus is a thermostable flavo­enzyme that is similar in amino-acid sequence and other properties to the flavoenzyme component of the NADH peroxidase systems from Salmonella typhimurium and Amphibacillus xylanus. The enzyme has been isolated from T. aquaticus and crystallized using the hanging-drop method of vapour diffusion with sodium citrate as a precipitant at pH 8.5. The crystals belong to the hexagonal space group P622 with unit-cell dimensions a = b = 89.9, c = 491.6 Å, and diffract to 2.5 Å resolution.