FATTY-ACID PATTERNS OF FILM-FORMING YEASTS AND NEW EVIDENCE FOR THE HETEROGENEITY OF PICHIA-MEMBRANAEFACIENS

Total fatty acids (C14:0 to C18:3) of 50 strains assigned by classical identification methods to Pichia membranefaciens (28), P. anomala (15 ), Dekkera anomala (2), D. bruxellensis (2) and Candida vini (3) were determined and data analysed by multivariate statistical procedures. P rincipal components cluster analysis defined six groups of strains. Th irteen strains of P. anomala formed a well-defined cluster, whereas P. membranaefaciens was split into three groups. The taxonomic status of the P. membranaefaciens strains was evaluated by determination of the G + C content and DNA-DNA hybridization. The results provided evidenc e in support of P. membranefaciens encompassing distinct species. Only eight strains were certified as P, membranefaciens and six were inclu ded in the same cluster, indicating that numerical analysis of fatty a cid profiles points to genetic differences which remain undetectable b y conventional phenotypic tests.