Characterization of a biocatalyst catalyzing biotransformation of highly branched fatty acids

Highly branched fatty acids are of particular interest as they have polyketide-like structures with several chiral centers and regioselective fictionalization of such substances would offer convenient routes to new important pharmaceutical compounds. A novel biocatalyst from Bacillus cereus was cloned and expressed in Escherichia coli BL21 using pET expression system. It can be easily expressed in E. coli with a high yield. The expressed recombinant enzyme was purified by Ni-NTA affinity chromatography and characterized. We elucidated that this enzyme catalyzes the oxidation of alkanoic acids (C8 to C17) and unsaturated fatty acids (C18). Substrate binding study showed the tightest binding fatty acid was myristic acid (C14), yielding a Kd value of 7.88 µM. This biocatalyst showed the activity of saturated fatty acids of shorter (C8, C10), which could not be observed from other enzyme.