ISSN:
1432-072X
Keywords:
13C NMR spectroscopy
;
Yeast
;
Debaryomyces hansenii
;
Osmoregulation
;
Compatible solute
;
Salt stress
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract High resolution 13C NMR combined with chemical analysis were used to study the formation of metabolites from [1-13C]-labelled glucose by the salt-tolerant yeast Debaryomyces hansenii after transfer to media containing 8% NaCl. Time course spectroscopy of an aerobic cell suspension showed [1,3-13C]glycerol as the predominant end product. Perchloric acid extracts revealed additional less prominent incorporation of label into arabinitol, trehalose, glutamic acid, and alanine. The incorporation into trehalose and arabinitol showed a transient increase after shift to the high salinity medium. It is concluded that glycerol and arabinitol are the major organic solutes in D. hansenii, the production of glycerol being strongly induced by high salinity. Analysis of labelled extracts of D. hansenii after transfer to 8% NaCl media containing [1-13C]- or [6-13C]glucose, demonstrated that glucose is dissimilated via a combination of the Embden-Meyerhof-Parnas pathway and the pentose phosphate pathway, with the former playing a major role in glycerol formation and the latter in arabinitol production. The almost exclusive labelling of C5 of arabinitol from [6-13C]glucose indicates that the pathway to arabinitol proceeds via reduction of ribulose-5-phosphate.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00248956
