Production of 1-Dodecanol, 1-Tetradecanol, and 1,12-Dodecanediol through Whole-Cell Biotransformation in Escherichia coli
Journal
Applied and Environmental Microbiology
Journal Volume
84
Journal Issue
4
Pages
Article number e01806-17
Date Issued
2018
Author(s)
Abstract
Medium- and long-chain 1-alkanol and α,ω-alkanediols are used in personal care products, in industrial lubricants, and as precursors for polymers synthesized for medical applications. The industrial production of α,ω-alkanediols by alkane hydroxylation primarily occurs at high temperature and pressure using heavy metal catalysts. However, bioproduction has recently emerged as a more economical and environmentally friendly alternative. Among alkane monooxygenases, CYP153A from Marinobacter aquaeolei VT8 (CYP153AM.aq; the strain is also known as Marinobacter hydrocarbonoclasticus VT8) possesses low overoxidation activity and high regioselectivity and thus has great potential for use in terminal hydroxylation. However, the application of CYP153AM.aq is limited because it is encoded by a dysfunctional operon. In this study, we demonstrated that the operon regulator AlkRM.aq is functional, can be induced by alkanes of various lengths, and does not suffer from product inhibition. Additionally, we identified a transposon insertion in the CYP153AM.aq operon. When the transposon was removed, the expression of the operon genes could be induced by alkanes, and the alkanes could then be oxyfunctionalized by the resulting proteins. To increase the accessibility of medium- and long-chain alkanes, we coexpressed a tunable alkane facilitator (AlkL) from Pseudomonas putida GPo1. Using a recombinant Escherichia coli strain, we produced 1.5 g/liter 1-dodecanol in 20 h and 2 g/liter 1-tetradecanol in 50 h by adding dodecane and tetradecane, respectively. Furthermore, in 68 h, we generated 3.76 g/liter of 1,12-dodecanediol by adding a dodecane-1-dodecanol substrate mixture. This study reports a very efficient method of producing C12/C14 alkanols and C12 1,12-alkanediol by whole-cell biotransformation.
Publisher
American Society for Microbiology
Type
journal article