Optimization of a Method for Isolating Plasmid DNA From Lactic Acid Bacteria From Wine

Abstract

Lactic acid bacteria play an important role in the manufacture of wines. They produce the deacidification of wine, contributing to the flavor and the microbiological stability of the final product (1,2). Many of the phenotypes that are paramount from a technological point of view could depend on plasmidencoded determinants. These include exopolysaccharide or bacteriocin production (3,4), proteinase activity (5), biogenic amines formation (6), malate or citrate fermentation (7), and so on. This fact justifies the research on the presence and characterization of wine lactic acid bacteria. Physical evidence for plasmids in bacteria was first presented in the early 1960s from the results of buoyant-density centrifugation in the presence of intercalating dyes, and electron microscope techniques (8). The discovery of plasmid DNA in the lactic acid bacteria was generally attributed to Cords et al. (9). Procedures for the detection and analysis of plasmids in bacteria were greatly simplified by the development of agarose gel electrophoresis methods for plasmid DNA (10), applied to the lactic acid bacteria by Klaenhammer et al. (11).