title: Molecular and physiological comparison of spoilage wine yeasts.
abstract: OBJECTIVE
  Dekkera bruxellensis and Pichia guilliermondii are contaminating yeasts in wine due to the production of phenolic aromas. Although the degradation pathway of cinnamic acids, precursors of these phenolic compounds has been described in D. bruxellensis, no such pathway has been described in P. guilliermondii.
  
  
  RESULTS
  A molecular and physiological characterization of 14 D. bruxellensis and 15 P. guilliermondii phenol-producing strains was carried out. Both p-coumarate decarboxylase (CD) and vinyl reductase (VR) activities, responsible for the production of volatile phenols, were quantified and the production of 4-vinylphenol and 4-ethylphenol were measured. All D. bruxellensis and some P. guilliermondii strains showed the two enzymatic activities, whilst 11 of the 15 strains of this latter species showed only CD activity and did not produce 4-EP in the assay conditions. Furthermore, PCR products obtained with degenerated primers showed a low homology with the sequence of the gene for a phenyl acrylic acid decarboxylase activity described in Saccharomyces cerevisiae.
  
  
  CONCLUSIONS
  D. bruxellensis and P. guilliermondii may share a similar metabolic pathway for the degradation of cinnamic acids.
  
  
  CONCLUSIONS
  This is the first work that analyses the CD and VR activities in P. guilliermondii, and the results suggest that within this species, there are differences in the metabolization of cinnamic acids.
authors: Grupo de Biodiversidad y Biotecnología de Levaduras, Instituto Multidisciplinario de Investigación y Desarrollo de la Patagonia Norte (IDEPA CONICET-UNCo), Dpto. de Química, Facultad de Ingeniería, Universidad Nacional del Comahue, Buenos Aires, Argentina.
authors: M P
authors: MP
authors: Sangorrín
authors: V
authors: V
authors: García
authors: C A
authors: CA
authors: Lopes
authors: J S
authors: JS
authors: Sáez
authors: C
authors: C
authors: Martínez
authors: M A
authors: MA
authors: Ganga
mesh_terms: D002262:Carboxy-Lyases / Q000378:metabolism; D002934:Cinnamates / Q000378:metabolism*; D055167:Dekkera / Q000235:genetics / Q000378:metabolism*; D005506:Food Contamination; D010088:Oxidoreductases / Q000378:metabolism; D010636:Phenols / Q000032:analysis; D010843:Pichia / Q000235:genetics / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D019105:Random Amplified Polymorphic DNA Technique; D014920:Wine / Q000382:microbiology*
chemical_list: D002934:Cinnamates; D010636:Phenols; C029010:cinnamic acid; C042291:4-ethylphenol; D010088:Oxidoreductases; D002262:Carboxy-Lyases; C087194:phenylacrylic acid decarboxylase; C030626:4-vinylphenol