Cloning and characterization of the lipase operon from Mycoplasma mycoides subspecies mycoides LC

Lipases, serine esterase enzymes, play an essential role in the mycoplasmal nutritional requirement for long-chain fatty acids. Although the lipase(s) activity in different mycoplasma species has been investigated, the molecular biology of the corresponding genes has not been studied. Using a single-primer PCR technique combined to more classical cloning systems, an operon containing three open reading frames (ORF), each of which could encode a lipase protein of 264, 264 or 269 amino acids (aa), was identified from Mycoplasma mycoides subsp. mycoides LC. Analysis of aa sequences of the encoded polypeptides showed that they display high aa similarity between each other (65-79%) and 28-31% identity to other prokaryotic lipases. Moreover, a lipase-esterase activity could be detected when the mycoplasmal lipase-encoding genes were expressed in a strong opal-suppressor-bearing Escherichia coli strain.