Beta-ketoacyl acyl carrier protein synthase III (FabH) is essential for fatty acid biosynthesis in Streptomyces coelicolor A3(2).

The Streptomyces coelicolor fab (fatty acid biosynthesis) gene cluster (fabD-fabH-acpP-fabF) is cotranscribed to produce a leaderless mRNA transcript. One of these genes, fabH, encodes a ketoacyl synthase III that is essential to and is proposed to be responsible for initiation of fatty acid biosynthesis in S. coelicolor.