Pichia guilliermondii

Genus/species (aliases): Pichia guilliermondii (Candida guilliermondii anamorph; Candida melibiosi, Endomyces guilliermondii)

Classification: Ascomycete, teleomorph

Morphology:

  • Cell: reproduces by budding, ellipsoidal, ovoidal, and clavate, occur singly and in pairs, or short chains; pseudohyphae formed.
  • Colony: SDA - flat, moist, smooth, cream to yellow.
  • Spore: hat-shaped ascospores, mostly found in nature in the haploid state; asexual blastospores also formed.
  • Zygote: Heterogamic or isogamic zygotes.
  • Ascus: evanescent; contain one or four spores.
  • Liquid Growth: pellicles formed are thin or lacking; rings may be formed.

 

Physiological Traits:

  • Fermentation: Glucose, Sucrose, Raffinose, Trehalose; variable: Galactose, Melibiose
  • Assimilation: Galactose, Glucosamine, Ribose, D-Xylose, Sucrose, Maltose, Trehalose, Raffinose, Glycerol, Ribitol, Xylitol, Succinate, Citrate, Ethanol, Variable: Sorbose, Arabinose, Rhamnose, Cellobiose, Salicin, Arbutin, Melibiose, Inulin, Lactate, Gluconate, Galactitol, Mannitol, Glucitol, Arabinitoll; no assimilation of nitrate; use of ethylamine, lysine and cadaverine as sole N source; no growth in vitamin-free medium, requires biotin
  • Growth: 35, 37, 40, 42 C: variable
  • Growth Sensitivities: resistant to 0.01% cycloheximide, some strains to 0.1%; 10% NaCl: +; 16% NaCl: variable; variable growth on high glucose
  • Chromosome bands: 6 to 8

Ecological Traits:

Found in wasps, human infections, sea water, faeces of animals, buttermilk, soil, grape juice and fish

Distinguishing Features:

Spore forming, in a hat or saturn-shape. If spores are spherical or ellipsoidal with a weak fermentation and is Asci dehiscent. Positive pellicle development: film develops in five days.

Role in wine:

Can be found in wine in barrels and lead to a cosmetic (film) or organoleptic defects in the wine. Spoilage of wine appear as a white scum on the surface, having a cheese-like appearance. Can bring about deleterious concentrations of ethyl acetate.

Sensitivities:

  • SO2: n/a
  • Sorbate­­­­­: n/a
  • DMDC: n/a
  • pH: n/a
  • Acids: n/a
  • Ethanol: n/a
  • Anaerobiosis: X
  • Heat: n/a

References:

  • Boulton, R., V. Singleton, L. Bisson, and R. Kunkee. 1996. Principles and Practices of Winemaking. Chapman & Hall, New York.
  • Wickerham, L.J. Validation of the species picia guilliermondii. 1966. Journal of Bacteriology. 92: 1269.