Open AccessIsolation and characterization of α‐aminoadipate‐δ‐semialdehyde overproducing mutants from yeasts
Author(s) -
Schmidt H.,
Bode R.,
Samsonova I.A.,
Birnbaum D.
Publication year - 1989
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1989.tb03446.x
Subject(s) - lysine , mutant , biochemistry , overproduction , yeast , pichia stipitis , biosynthesis , biology , enzyme , reductase , chemistry , saccharomyces cerevisiae , amino acid , gene
We isolated from Candida maltosa mutants lacking saccharopine reductase ( lys9 ) and saccharopine dehydrogenase ( lys1 ). They accumulated α‐aminoadipate‐δ‐semialdehyde (AASA) in the cell and excreted it into the culture medium. In the presence of 15 g glucose/l, 1.25 g NH 4 H 2 PO 4 /l and 50 mg l ‐lysine/l in a minimal salt medium C. maltosa G285 ( lys1 ) produced about 80–90 mg AASA/l within 48 h. It is the first report of lysine‐requiring yeast mutants that accumulate and excrete AASA. In contrast, Pichia guilliermondii lys9 mutants lacked this AASA overproduction. The AASA accumulation by C. maltosa mutants may be explained by the low feedback regulation of their homocitrate synthase and the equilibrium of the enzyme reactions involved in the lysine biosynthesis.