IN-VITRO REASSEMBLY OF THE MALOLACTIC FERMENTATION PATHWAY OF LEUCONOSTOC-OENOS (OENOCOCCUS-OENI)

The mechanism of metabolic energy generation by malolactic fermentatio n was studied with artificial membrane vesicles of Leuconostoc oenos ( Oenococcus oeni), (Note that although L. oenos was recently reclassifi ed as O. oeni [L. M. T. Dicks, F. Dellaglio, and M. D. Collins, Int. J . Syst. Bacteriol. 45:395-397, 1995], the old designation was kept in the present work,) Purified malolactic enzyme was entrapped in artific ial membrane vesicles prepared from L. oenos cells able to transport L -malate. We show that the in vitro reconstituted system, including an electrogenic L-malate carrier and the decarboxylating malolactic enzym e, generated a proton motive force that was able to drive intravesicul ar accumulation of leucine.