Exploring a Streptomyces wax synthase using acyl-SNACs as donor substrates

The demand of fragrance and food industries for short/branched wax esters is increasing due to their rich scent and low toxicity. Wax synthase and acyl-CoA:diacylglycerol O-acyltransferase (WS/DGAT) are a family of bacterial enzymes capable of catalysing the production of wax esters. Here, we report that a WS/DGAT from Streptomyces coelicolor is able to mediate the reactions between alcohol acceptors and synthetic acyl-donor mimics, acyl-SNACs. The enzyme displayed considerable substrate tolerance towards acyl-donors with structural diversity. Structural modelling-guided site directed mutagenesis resulted in a variant, L25F, the catalytic efficiency of which was improved toward aromatic, short-linear, and branched acyl-donors compared to the wild type.