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)
1. In rats, liver 4-hydroxy-2-oxoglutarate aldolase and hydroxyproline oxidase activities are maximal in the suckling period. 2. Liver activities for 4-hydroxy-2-oxoglutarate aldolase,
alanine-glyoxylate aminotransferase
, serine-pyruvate aminotransferase and
serine dehydratase
, but not hydroxyproline oxidase, are increased in rats on a high-fat, carbohydrate-free diet. 3. It is suggested that 4-hydroxy-2-oxoglutarate may be a significant source of glyoxylate for glycine and hence glucose formation. 4. Mammalian liver hydroxyproline oxidase activity is higher in carnivorous species; necessary, perhaps, to metabolise a relatively large influx of hydroxyproline on a flesh diet.
...
PMID:Comparative and developmental studies on 4-hydroxy-2-oxoglutarate aldolase and hydroxyproline oxidase. 708 20
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
L-Serine metabolism in rabbit, dog, and human livers was investigated, focusing on the relative contributions of the three pathways, one initiated by
serine dehydratase
, another by serine:pyruvate/alanine:glyoxylate aminotransferase (SPT/
AGT
), and the other involving serine hydroxymethyltransferase and the mitochondrial glycine cleavage enzyme system (GCS). Under quasi-physiological in vitro conditions (1 mM L-serine and 0.25 mM pyruvate), flux through
serine dehydratase
accounted for only traces, and that through SPT/
AGT
substantially contributed no matter whether the enzyme was located in peroxisomes (rabbit and human) or largely in mitochondria (dog). As for flux through serine hydroxymethyltransferase and GCS, the conversion of serine to glycine occurred fairly rapidly, followed by GCS-mediated slow decarboxylation of the accumulated glycine. The flux through GCS was relatively high in the dog and low in the rabbit, and only in the dog was it comparable with that through SPT/
AGT
. An in vivo experiment with L-[3-3H,14C]serine as the substrate indicated that in rabbit liver, gluconeogenesis from L-serine proceeds mainly via hydroxypyruvate. Because an important role in the conversion of glyoxylate to glycine has been assigned to peroxisomal SPT/
AGT
from the studies on primary hyperoxaluria type 1, these results suggest that SPT/
AGT
in this organelle plays dual roles in the metabolism of glyoxylate and serine.
...
PMID:Flux of the L-serine metabolism in rabbit, human, and dog livers. Substantial contributions of both mitochondrial and peroxisomal serine:pyruvate/alanine:glyoxylate aminotransferase. 1034 52