Isolation and biochemical characterization of a new NADH oxidase from Lactobacillus brevis

摘要

A new NADH oxidase, useful for the regeneration of NAD~+, was isolated and characterized from Lactobacillus brevis. In crude extracts the activity was from 10-15 U mg~(-1). After purification by four chromatographic steps, an activity of 116 U mg~(-1) was obtained with 14% yield. Highest activity was from pH 5.5-7 and at 40 deg C. The enzyme requires dithiothreitol to prevent oxidative deactivation. The K_m value for NADH was 24muM.