Crystallization and preliminary X-ray crystallographic studies of β-transaminase from Mesorhizobium sp. strain LUK

摘要

β-Transaminase (β-TA) catalyzes the transamination reaction between β-­aminocarboxylic acids and keto acids. This enzyme is a particularly suitable candidate for use as a biocatalyst for the asymmetric synthesis of enantiochemically pure β-amino acids for pharmaceutical purposes. The β-TA from Mesorhizobium sp. strain LUK (β-TAMs) belongs to a novel class in that it shows β-­transaminase activity with a broad and unique substrate specificity. In this study, β-TAMs was overexpressed in Escherichia coli with an engineered C-­terminal His tag. β-­TAMs was then purified to homogeneity and crystallized at 293 K. X-­ray diffraction data were collected to a resolution of 2.5 Å from a crystal that belonged to the orthorhombic space group C2221, with unit-cell parameters a = 90.91, b = 192.17, c = 52.75 Å.