Authors
Chunhui Zhao, Yoichi Kumada, Hiroyuki Imanaka, Koreyoshi Imamura, Kazuhiro Nakanishi
First author
Chunhui Zhao
Corresponding author
Kazuhiro Nakanishi
Publication Style
Journal name Protein expression and purification
Year
Volume, issue, pages
47(2) 607-13
Abstract
O-Acetylserine sulfhydrylase-B (OASS-B, EC 2.5.1.47) is one of the two isozymes produced by Escherichia coli that catalyze the synthesis of l-cysteine from O-acetyl-l-serine and sulfide. The cysM gene encoding OASS-B was cloned and the enzyme was overexpressed in E. coli using pUC19 with a lacUV5 promoter. The enzyme was purified to homogeneity, as evidenced by SDS–PAGE. Approximately 300 mg of purified OASS-B was obtained from 1600 mL of culture broth with a purification yield of 60% or higher. The purified OASS-B was characterized and its properties compared with OASS-A. OASS-B did not form a complex with E. coli serine acetyltransferase (SAT, EC 2.3.1.30) and showed a wide range of substrate specificity in nonproteinaceous amino acid synthesis.