 Furthermore, as with "E. coli", an influx of propionyl-CoA in "Myobacterial" species can result in toxicity if not dealt with immediately.This toxicity is caused by a pathway involving the lipids that form the bacterial cell wall.Using esterification of long-chain fatty acids, excess propionyl-CoA can be sequestered and stored in the lipid, triacylglycerol (TAG), leading to regulation of elevated propionyl-CoA levels.