Tyrosine metabolism: identification of a key residue in the acquisition of prephenate aminotransferase activity by 1β aspartate aminotransferase
نویسندگان
چکیده
منابع مشابه
Deciphering the role of aspartate and prephenate aminotransferase activities in plastid nitrogen metabolism.
Chloroplasts and plastids of nonphotosynthetic plant cells contain two aspartate (Asp) aminotransferases: a eukaryotic type (Asp5) and a prokaryotic-type bifunctional enzyme displaying Asp and prephenate aminotransferase activities (PAT). We have identified the entire Asp aminotransferase gene family in Nicotiana benthamiana and isolated and cloned the genes encoding the isoenzymes with plastid...
متن کاملTyrosine biosynthesis in Sorghum bicolor: characteristics of prephenate aminotransferase.
A stable activity which transfers the amino group from glutamate to prephenate was extracted from 4-day old etiolated shoots of sorghum. The activity was retained on DEAE cellulose and eluted as a single peak. Prephenate aminotransferase co-eluted with a very abundant alpha-ketoglutarate: aspartate aminotransferase, but heating at 70 degrees C resulted in loss of alpha-ketoglutarate: aspartate ...
متن کاملUnexplained High Activity of Aspartate Aminotransferase in an Asymptomatic Pediatric Patient
Elevated enzyme activities in plasma may at times be attributed to the presence of macro-enzymes. The macro-enzymes are often serum enzymes in complex with immunoglobulins, resulting in a greater molecular mass that cannot be filtered by renal glomeruli and are, hence, retained in the plasma. The aspartate aminotransferase (AST) can exist as a macro-enzyme, although it has been rarely reported....
متن کاملAspartate: 2-oxoglutarate aminotransferase from trichomonas vaginalis. Identity of aspartate aminotransferase and aromatic amino acid aminotransferase.
Aspartate: 2-oxoglutarate aminotransferase from the anaerobic protozoon Trichomonas vaginalis was purified to homogeneity and characterized. It is a dimeric protein of overall Mr approx. 100000. Only a single isoenzyme was found in T. vaginalis. The overall molecular and catalytic properties have features in common with both the vertebrate cytoplasmic and mitochondrial isoenzymes. The purified ...
متن کاملPhotoinactivation of aspartate aminotransferase.
The cofactor pyridoxal 5’-phosphate bound through an aldimine linkage to lysine residues of the enzyme aspartate amiuotransferase is very stable to irradiation with light of 420 nm. The catalytic function of the enzyme exposed to light absorbed by the cofactor remains unaffected, indicating that pyridoxal 5’-phosphate is not an efficient active site photosensitizer for this aminotransferase. Th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The FEBS Journal
سال: 2019
ISSN: 1742-464X,1742-4658
DOI: 10.1111/febs.14789