GREAT AT SMALL THINGS

Physiological profiling of yeasts

Yeasts may be characterised by their diverse abilities to metabolise carbon and nitrogen sources, to grow under various environmental conditions such as the presence or absence of vitamins, a range of pH values and temperatures. A range of assimilation, fermentation and inhibition tests were used in the past to identify yeast species. However, with the routine use of DNA sequences also for species discovery, many new species have been found that are indistinguishable from related species by their physiological profiles. A certain variability of physiological profiles within species complicates their interpretation. Physiological profiles serve no longer for valid species identification. Nevertheless, physiological profiles provide valuable information on the metabolic capabilities of yeast strains that may be of interest in ecological and other research as well as in brewery, bioethanol and other industries.

BCCM/MUCL offers the determination of 12 carbohydrate fermentation, 59 carbon compound assimilation, 12 nitrogen assimilation, 10 vitamin and 12 other reactions of pure yeast cultures. Tests are performed in microplates and results determined in a semi-automated procedure according to an in-house developed protocol [link to miniposter]. The report comprises the list of qualitative test results (positive, negative, weak, delayed) and a comparison with an extensive in-house database.

Contact: Heide-Marie Daniel

Literature:

Robert V, Evrard P, Hennebert GL 1997 BCCM/Allev 2.00 an Automated system for the identification of yeasts, Mycotaxon 64: 455-463.

Robert V 2003 Data processing In: T. Boekhout & V. Robert (Eds) Yeasts in Food: Beneficial and Detrimental Aspects. Behrs Verlag, Hamburg pp. 139-163.

Robert V 2007 Data integration and multi-factorial analyses, the yeasts and the BioloMICS software as a case study. In: N. MacLeod (Ed) Automated object identification in systematics: Theory, approaches, and applications. Taylor & Francis, London pp. 277-288.