The long range purpose of this project is to study the biochemical processes involved in the growth of bacterial cell wall and membrane and the coupling of these processes to DNA replication during cell division. The present goal is to determine the functional role of lipoteichoic acid in Staphylococcus aureus and other Gram-positive bacteria. Lipoteichoic acids are polymers of glycerol phosphate found intracellularly closely associated with plasma membranes and with membranous bodies known as mesosomes. One of the polyglycerol phosphates, lipoteichoic carrier, has been implicated by others in the synthesis of cell wall teichoic acid. This material is a minor component of the lipoteichoic acid fraction. The function of the remainder of the lipoteichoic acid (LTA) is not known and this is the area of current interest. Present studies are directed at: 1) relating LTA content to cellular growth; 2) location of LTA within Gram-positive bacteria other than S. aureus; 3) location of LTA within the mesosome.