Fatty Acid Synthase II System (FAS II)

The Fatty Acid Synthase II system (FAS II) is a multi-enzyme pathway responsible for the de novo synthesis of fatty acids, primarily in bacteria, plants, and mitochondria of eukaryotes. Unlike the mammalian FAS I system, FAS II consists of discrete, monofunctional enzymes that each catalyze individual steps in the fatty acid elongation cycle. It is essential for cell membrane biosynthesis in bacteria and is a target for antibiotic development. The process begins with acetyl-CoA as a primer and uses malonyl-CoA as an extender unit, with NADPH serving as a reducing agent. Key enzymes include ketoacyl synthase (KS), ketoacyl reductase (KR), dehydratase (DH), and enoyl reductase (ER).

Inhibition of bacterial fatty acid synthesis