Unveiling of novel regio-selective fatty acid double bond hydratases from Lactobacillus acidophilus involved in the selective oxyfunctionalization of mono- and di-hydroxy fatty acids

• Published in: Biotechnology and bioengineering Vol. 112; no. 11; pp. 2206 - 2213
• Main Authors: Kim, Kyoung-Rok, Oh, Hye-Jin, Park, Chul-Soon, Hong, Seung-Hye, Park, Ji-Young, Oh, Deok-Kun
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.11.2015; Wiley Subscription Services, Inc
• Subjects: 10,13‐dihydroxy‐octadecanoic acid; 13-dihydroxy-octadecanoic acid; 13-hydroxy-9(Z)-octadecenoic acid; Bioengineering; Biotechnology; Enzymes; Fatty acids; Fatty Acids - metabolism; Feedstock; Genes; Genomics; Gram-positive bacteria; Hydro-Lyases - genetics; Hydro-Lyases - metabolism; hydroxy fatty acid; Hydroxylation; Kinetics; Lactobacillus acidophilus; Lactobacillus acidophilus - enzymology; Lactobacillus acidophilus - genetics; linoleate 13-hydratase; linoleic acid; Recombinant; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; regio-selective hydroxylation; Substrate Specificity; regio-selective hydroxylation; linoleate 13-hydratase; 13-hydroxy-9(Z)-octadecenoic acid; linoleic acid; hydroxy fatty acid; 10,13-dihydroxy-octadecanoic acid; Lactobacillus acidophilus
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/bit.25643

ABSTRACT The aim of this study is the first time demonstration of cis‐12 regio‐selective linoleate double‐bond hydratase. Hydroxylation of fatty acids, abundant feedstock in nature, is an emerging alternative route for many petroleum replaceable products thorough hydroxy fatty acids, carboxylic acids, and lactones. However, chemical route for selective hydroxylation is still quite challenging owing to low selectivity and many environmental concerns. Hydroxylation of fatty acids by hydroxy fatty acid forming enzymes is an important route for selective biocatalytic oxyfunctionalization of fatty acids. Therefore, novel fatty acid hydroxylation enzymes should be discovered. The two hydratase genes of Lactobacillus acidophilus were identified by genomic analysis, and the expressed two recombinant hydratases were identified as cis‐9 and cis‐12 double‐bond selective linoleate hydratases by in vitro functional validation, including the identification of products and the determination of regio‐selectivity, substrate specificity, and kinetic parameters. The two different linoleate hydratases were the involved enzymes in the 10,13‐dihydroxyoctadecanoic acid biosynthesis. Linoleate 13‐hydratase (LHT‐13) selectively converted 10 mM linoleic acid to 13S‐hydroxy‐9(Z)‐octadecenoic acid with high titer (8.1 mM) and yield (81%). Our study will expand knowledge for microbial fatty acid‐hydroxylation enzymes and facilitate the designed production of the regio‐selective hydroxy fatty acids for useful chemicals from polyunsaturated fatty acid feedstocks. Biotechnol. Bioeng. 2015;112: 2206–2213. © 2015 Wiley Periodicals, Inc. By genomic analysis and comparison, two hydratases were isolated and characterized as novel cis‐12 and cis‐10 position‐selective linoleate hydratase. Function of two linoleated hydratase are involved in the dihydroxy fatty acid formation. A novel cis‐12 linoleate hydrates selectively produced 10‐ and 13‐hydroxy fatty acids from polyunsaturated fatty acids with high yield. These hydratases will be feasible tool for mono‐ and dihydroxy fatty acid oxyfunctionalization.