Derepressed utilization of L-malic acid and succinic acid by mutants of Pachysolen tannophilus.
Utilization of the tricarboxylic acid (TCA) cycle intermediates, L-malic acid and succinic acid, by the yeast Pachysolen tannophilus is repressed in the presence of glucose. Strains of P. tannophilus containing mutations in two hexokinases and a glucokinase were characterized for growth on glucose plus L-malic acid or succinic acid. Increased specific utilization rates of malic acid and succinic acid in the presence of glucose were observed in mutants containing a lesion in hexokinase A, an enzyme associated with catabolite repression. Such derepressed mutants may have application in winemaking in which utilization of a major grape acid, L-malic acid, is often desirable for acidity reduction.
Harrod
C J
CJ
Department of Microbiology and Genetics, Massey University, Palmerston North, New Zealand.
Rodriguez
S B
SB
Thornton
R J
RJ
D005947:Glucose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008293:Malates / Q000378:metabolism*; D009154:Mutation; D004718:Saccharomycetales / Q000378:metabolism*; D013386:Succinates / Q000378:metabolism*; D019802:Succinic Acid
D008293:Malates; D013386:Succinates; C030298:malic acid; D019802:Succinic Acid; D005947:Glucose