Transacylation Kinetics in Fatty Acid and Polyketide Synthases and its Sensitivity to Point Mutations**

Fatty acid and polyketide synthases (FASs PKSs) synthesize physiologically pharmaceutically important products by condensation of acyl building blocks. The transacylation reaction catalyzed transferases (ATs) is responsible for the selection acyl-CoA esters further processing FASs PKSs. In this study, AT domains different multidomain (type I) PKS systems are kinetically described in their substrate selectivity, AT?Acyl carrier protein (ACP) domain-domain interaction enzymatic kinetic properties. We observe that ATs modular PKSs, intricate complexes occurring bacteria biosynthesis bioactive polyketides, significantly slower than mammalian FASs, reflecting respective purpose biosynthetic pathways within organism metabolic context. perform a mutational study on kinetics AT?ACP 6-deoxyerythronolide B synthase (DEBS) find high plasticity enzyme properties, which we explain recognition. Our enlarges understanding its molecular properties similarly call thorough AT-centered engineering strategies.