Genus/species (aliases): Hanseniaspora guilliermondii (Kloeckera apis anamorph; Acaromyces laviae, Hanseniaspora apuliensis, Hanseniaspora melligeri, Kloeckera apiculata, Willia guilliermondii)
Classification : Ascomycete, teleomorph
Morphology:
- Cell: reproduction by budding; apiculate (lemon-shaped) with bipolar budding
- Colony: Malt agar: cream-to butter colored,, smooth, glossy, convex
- WL: flat colonies, intense green
- Spore: Hat Shaped Ascospores
- Zygote:Dumb-Bell Shaped
- Ascus: Up to four ascospores per ascus; ascus is evanescent
- Liquid Growth: (ie dispersed, pellicle, film, clumpy) Form a sediment and thin ring after one month in YM liquid medium.
Physiological Traits:
- Fermentation: Glucose, Cellibiose variable
- Assimilation: Cellobiose, Salicin, Arbutin, Gluconate; no assimilation of nitrate or nitrite; Ethylamine used as sole N source; use of lysine, tryptophan, cadaverine as sole N soure present to weak; no growth on vitamin-free medium, requires biotin, thiamin, pyridoxine, niacin.
- Growth 37 C: +
- Growth Sensitivities: Resistant to cycloheximide, high glucose concentrations, 10% NaCL: +, 16% NaCl variable
- Products: esters, glycerol, ethanol, acetoin, acetaldehyde, trace hydrogen sulfide
Ecological Traits:
Found on dates, grapes, tomatoes, figs and in soil
Distinguishing Features:
- Four ascospores per ascus,
- Assimilates 2 Keto-D-Gluconate,
- Can grow at 37 ºC,
- Cycloheximide resistant
- Can use lysine as N source
Role in wine:
Associated with damaged grapes. Hanseniaspora sp. are naturally present on plants, especially damaged fruit. They have been implicated in stuck fermentations, possibly from thiamin depletion. Non-Saccharomyces yeast like Hanseniaspora sp. are the dominate form of yeast on grapes and during the initial phase of an uninoclated fermentation. Growth declines when ethanol or sulfur dioxide reaches an inhibitory concentration.
Sensitivities:
SO2:Variable, but more sensitive than Saccharomyces
Sorbate: 100-200 ppm
DMDC: 100mg/L
pH: 2.0-8.0
Acids: benzoic acid
Ethanol sensitive: >5%
Anaerobiosis: Crabtree Positive, ferments <150 g="" glucose="" l="" p="">
Heat: sensitive >37ºC