Open AccessIdentification and characterization of a novel glucose‐phosphorylating enzyme in Kluyveromyces lactis
Author(s) -
Kettner Karina,
Müller EvaChristina,
Otto Albrecht,
Rödel Gerhard,
Breunig Karin D.,
Kriegel Thomas M.
Publication year - 2007
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/j.1567-1364.2007.00259.x
Subject(s) - kluyveromyces lactis , biology , kluyveromyces , phosphorylation , enzyme , biochemistry , identification (biology) , computational biology , yeast , saccharomyces cerevisiae , botany
Recent data suggest that hexokinase KlHxk1 (Rag5) represents the only glucose‐phosphorylating enzyme of Kluyveromyces lactis , which also is required for glucose signalling. Long‐term growth studies of a K. lactis rag5 mutant, however, reveal slow growth on glucose, but no growth on fructose. Isolation of the permissive glucose‐phosphorylating enzyme, mass spectrometric tryptic peptide analysis and determination of basic kinetic data identify a novel glucokinase (KlGlk1) encoded by ORF KLLA0C01155g . In accordance with the growth characteristics of the rag5 mutant, KlGlk1 phosphorylates glucose, but fails to act on fructose as a sugar substrate. Multiple sequence alignment indicates the presence of at least one glucokinase gene in all sequenced yeast genomes.