Formaldehyde as a carbon and energy source in yeast growth

Abstract

Summary Formaldehyde can simultaneously be utilized by yeasts during growth on another heterotrophic substrate (e.g. glucose, xylose, methanol). From transient state growth experiments it became evident with Hansenula polymorpha that up to a molar mixing ratio of formaldehyde to glucose of 3 the former seems to play the role of an energy donor for glucose carbon incorporation. This also holds for the non-methylotrophic yeast Candida utilis. At higher mixing ratios formaldehyde is used as a carbon and energy source besides glucose in the case of H. polymorpha. Formaldehyde utilization in the mixture is limited by the capacity of formate dehydrogenase. In contract, with C. utilis formaldehyde dehydrogenase activity limits consumption of this substrate in the mixture. The results with this yeast suggest that formaldehyde is not used significantly as a carbon source.