Characteristics of alanine racemase in <i>Lactobacillus sakei</i><scp>ZH</scp>‐2 strain

Some d-amino acid functions for food production are widely known: d-alanine improves sensory evaluations of sake, beer, and fermented foods. Therefore, the application acids, alanine racemase (ALRase) in Lactobacillus sakei ZH-2, which has strong racemization, was analyzed using molecular biological methods. It had been hypothesized that ALRase coding DNA, alr, ZH-2 strain differs from those other strains. However, complete genome sequencing by National Center Biotechnology (NCBI) revealed amino sequence alr to have homology 99.4% similarity with 23K strain. it is considered a unique lactic bacteria group. DNA “alr” 1140 bp base 41 kDa mass. Its mass inferred as approximately 38.0 SDS-PAGE. optimum conditions pH 9.0 at 30–40°C, showing stability 9.0–10.0 4–40°C. cofactor pyridoxal phosphate. activity activated more copper zinc ions than lack metal ion. Additionally, its Km 1.32 × 10−3 (mol), Vmax 4.27 10−5 (μmol−1 min−1). reacted against most strongly substrates such acids. The enzyme serine found 40% alanine. converted up 54.5% l-alanine