A cold‐adapted leucine dehydrogenase from marine bacterium Alcanivorax dieselolei: Characterization and l‐tert‐leucine production. Issue 3 (28th December 2015)

• Record Type: Journal Article
• Authors: Jiang, Wei; Sun, Dongfang; Lu, Jixue; Wang, Yali; Wang, Shizhen; Zhang, Yonghui; Fang, Baishan
• Is Part Of: Engineering in life sciences. Volume 16:Issue 3(2016)
• Page Start: 283
• Page End: 289
• Publication Date: 2015-12-28
• Subjects: Alcanivorax dieselolei -- Cold adaptation -- Extreme environments -- LeuDH -- l‐tert‐leucine enzymatic production; Bioengineering -- Periodicals; 660.605
• DOI: 10.1002/elsc.201500092
• Languages: English
• ISSNs: 1618-0240

Abstract

Abstract : l ‐ tert ‐leucine, an intermediate in the synthesis of several chiral drugs, is mainly produced by bioconversion, in which leucine dehydrogenase (LeuDH) is the key enzyme. A novel leudh was obtained from the marine bacterium Alcanivorax dieselolei B‐5(T) by PCR. The gene encoded a novel cold‐adapted LeuDH that showed low similarity (less than 50%) to any known proteins; the highest similarity (42.6%) was found for LeuDH from Bacillus cereus . The cold‐adapted LeuDH showed optimal activity at 30℃ and pH 6.5, and was identified to be extremely cold‐adaptive, retaining over 90% activity in the temperature range of 0–37℃. The enzyme exhibited better stability in weak alkali environment (pH 6.0–8.5) than Thermoactinomyces intermedius LeuDH. The best substrate concentration was established, and LeuDH conversion rate in catalyzing trimethylpyruvic acid tol ‐ tert ‐leucine was 54.6%. The cold activity and its ability to producel ‐ tert ‐leucine with excellent performance of enantiomers of choice make it a promising biocatalyst for industrial application under extreme conditions.