– 3-hydroxy Palmitic acid is a form of the 16:0 lipid palmitic acid. The lipid A part of lipopolysaccharides contain various 3-hydroxy fatty acids, making oxylipins such as 3-hydroxy palmitic acid useful as chemical markers of endotoxins. In R. solanacearum, 3-hydroxy palmitic acid is converted by an S-adenosyl methionine-dependent methyltransferase to 3-hydroxy palmitic acid methyl ester, which acts as a quorum sensing signal molecule for post-transcriptional modulation of genes involved in virulence. Long-chain 3-hydroxy fatty acids, such as 3-hydroxy palmitic acid, are also known to accumulate during long-chain 3-hydroxy-acyl-CoA dehydrogenase and mitochondrial trifunctional protein deficiencies. Such accumulation induces oxidative stress, leading to mitochondrial bioenergetics deregulation and eventual multi-organ dysfunction.