A mathematical model explaining the molecular weights and distribution of very long chain dicarboxylic acids formed during the adaptive response of sarcina ventriculi

A simple mathematical model is presented to explain a recent new discovery of an unusual membrane adaptive response inSarcina ventriculi.In this response, this organism synthesizes very long chain α,ω-dicarboxylic acids ranging from 28 to 36 carbon atoms in length. The distribution of chain lengths of the new fatty acid species is not consistent withde novosynthesis but suggests elaboration from the existing regular-chain fatty acids by a coupling process. Here, we demonstrate, using a mathematical model, that if the molecular weights and relative abundances of regular chain fatty acids are known, the molecular weights and relative abundances of the new, very long chain dicarboxylic fatty acid species can be predicted using a model based on the random, pairwise combination of regular chain species. This combination takes place across the bilayer leaflet to form transmembrane fatty acids. It is proposed that this coupling phenomenon is regulated by the motional dynamics of the membrane.