Structure-Based Design of Acetolactate Synthase From Bacillus licheniformis Improved Protein Stability Under Acidic Conditions.

ABSTRACT: Catabolic acetolactate synthase (cALS) plays a crucial role in the quality of liquor because of its ability to catalyze the synthesis of the endogenous precursor product α-acetolactate of the aromatic compound tetramethylpyrazine (TTMP) and acetoin. However, the vulnerability of cALS to acidic conditions limits its application in the Chinese liquor brewing industry. Here we report the biochemical characterization of cALS from B. licheniformis T2 (BlALS) that was screened from Chinese liquor brewing microorganisms. BlALS showed optimal activity levels at pH 7.0, and the values of K _m and V_max were 27.26 mM and 6.9 mM⋅min^-1, respectively. Through site-directed mutagenesis, we improved the stability of BlALS under acidic conditions. Replacing the

SUBMITTER: Zhao T 

PROVIDER: S-EPMC7652814 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature