|
type |
Journal Article |
authors |
Ono, B.; Naito, K.; Shirahige, Y.; Yamamoto, M. |
title |
Regulation of cystathionine gamma-lyase in Saccharomyces cerevisiae |
journal |
Yeast |
Activity |
4.4.1.1 |
Family |
4.4.1.1 |
ui |
92160391 |
year |
(1991) |
volume |
7 |
number |
8 |
pages |
843-8. |
| |
keywords |
Cystathionine gamma-Lyase/*metabolism |
abstract |
Regulation of the two enzymes in reverse trans-sulfuration was investigated in Saccharomyces cerevisiae. In wild-type strains, cystathionine gamma-lyase, but not cystathionine beta-synthase, was depressed nearly 15-fold if cells were starved for both inorganic and organic sulfur compounds. In a met17 strain which is defective of O- acetylserine and O-acetylhomoserine sulfhydrylase, the same enzyme was derepressed if organic sulfur compounds were limited; the repressive effect was in the order of glutathione greater than methionine greater than cysteine. The repressive effect of methionine was not observed, however, in a cys2 cys4 strain which is deficient of serine O- acetyltransferase and cystathionine beta-synthase, indicating that methionine itself is not the effector. The weak repressive effect of cysteine was attributed to inefficient uptake of this amino acid. Our observations indicate that cystathionine gamma-lyase is the target of regulation in reverse trans-sulfuration and that cysteine is very likely to be the effector of this regulation. |
last changed |
2008/04/02 19:23 |
|