Genetic Analysis of SCO2997, Encoding a TagF Homologue, Indicates a Role for Wall Teichoic Acids in Sporulation of

Streptomyces coelicolor contains two gene clusters putatively involved in wall teichoic acid biosynthesis. Inactivation of the tagF homologue SCO2997 or SCO2584, a component of the Streptomyces spore wall synthe-sizing complex, affected sporulation. The mutant phenotypes resembled those of mre mutants, suggesting a function of wall teichoic acids in the differentiation of Streptomyces. The cell wall of Gram-positive bacteria consists of pep-tidoglycan (PG), lipoteichoic acids (LTA), wall teichoic acids (WTA), and other polysaccharides and proteins (34). Thirty percent to 60 % of the cell wall is made of teichoic acids (26, 37). Common types of WTA consist of glycerolphosphate or ribitolphosphate subunits that are connected by phosphodi-ester bonds (40). WTA are involved in cation homeostasis (1, 14), antibiotic resistance (20, 21), and the release of secreted proteins (27). Glycerol-WTA biosynthesis in Bacillus subtilis 168 starts in the cytosol by the synthesis of the linker made of N-acetylglucosamine (GlcNAc), N-acetylmannosamine (Man