Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.6.1.44 (
AGT
)
770
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
L-Serine metabolism in rat liver was investigated, focusing on the relative contributions of the three pathways, one initiated by
L-serine dehydratase
(SDH), another by serine:pyruvate/alanine:glyoxylate aminotransferase (SPT/
AGT
), and the other involving serine hydroxymethyltransferase and the mitochondrial glycine cleavage enzyme system (GCS). Because serine hydroxymethyltransferase is responsible for the interconversion between serine and glycine, SDH, SPT/
AGT
, and GCS were considered to be the metabolic exits of the serine-glycine pool. In vitro, flux through SDH was predominant in both 24-h starved and glucagon-treated rats. Flux through SPT/
AGT
was enhanced by glucagon administration, but even after the induction, its contribution under quasi-physiological conditions (1 mM L-serine and 0.25 mM pyruvate) was about (1)/(10) of that through SDH. Flux through GCS accounted for only several percent of the amount of L-serine metabolized. Relative contributions of SDH and SPT/
AGT
to gluconeogenesis from L-serine were evaluated in vivo based on the principle that 3H at the 3 position of L-serine is mostly removed in the SDH pathway, whereas it is largely retained in the SPT/
AGT
pathway. The results showed that SPT/
AGT
contributed only 10-20% even after the enhancement of its activity by glucagon. These results suggested that SDH is the major metabolic exit of L-serine in rat liver.
...
PMID:Flux of the L-serine metabolism in rat liver. The predominant contribution of serine dehydratase. 1034 51