Submitted to: American Society for Microbiology General Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 6/2/2015
Publication Date: 6/1/2015
Citation: Liu, S., Bischoff, K.M. 2015. Novel ferulate esterase from Gram-positive lactic acid bacteria and analyses of the recombinant enzyme produced in E. coli. [abstract]. American Society for Microbiology. Poster #305, p. 115.
Technical Abstract: Using a plate containing ethyl ferulate as sole carbon source, various bacteria cultures were screened for ferulate esterase (FAE). Among a dozen of species showing positive FAE, one Lactobacillus fermentum strain NRRL 1932 demonstrated the strongest activity. Using a published sequence of ferulate esterase gene (GenBank: AY837784.1) from Burkholderia multivorans (Rashamuse et al., 2007) as query sequence, the genome of L. fermentum IFO 3956 (Morita et al., 2008) was searched and one hypothetical protein LAF_1318 (GI: 184155794) was identified as the putative ferulate esterase. Polymerase chain reaction (PCR) primers were designed based on the LAF_1318 sequences and the corresponding FAE gene was amplified from L. fermentum NRRL B-1932 and subcloned into an expression vector pET28b (Novagen) at the NcoI/BamHI sites. The 29.6 kDa recombinant protein was produced by E.coli BL21pLys upon IPTG induction, and the recombinant FAE was purified using the HIS tag sequence from the expression vector. The purified FAE showed strong activities against several artificial substrates including p-nitrophenyl acetate, 4-methylumbelliferyl p-trimethylammonium cinnamate chloride. The optimal pH of the recombinant FAE is around 6.5 and optimal temperature is around 37 o C. These studies demonstrated that the bacterial ferulate esterase can be produced and purified for commercial applications.