Fumiya Nagashima

Learn More
cDNA clones for rat cytosolic aspartate aminotransferase (cAspAT, L-aspartate:2-oxoglutarate aminotransferase) [EC] were isolated from a rat cDNA library, and the primary structure of the gene for cAspAT was deduced from its cDNA sequence. Rat cAspAT consists of 412 amino acids and its molecular weight is 46,295. The deduced amino acid sequence of(More)
The nucleotide sequences of mRNAs for the mouse mitochondrial and cytosolic aspartate aminotransferase isoenzymes (mAspAT and cAspAT) (EC were determined from complementary DNAs. The mAspAT mRNA comprises minimally 2460 nucleotides and codes for a polypeptide of 430 amino acid residues corresponding to the precursor form of the mAspAT (pre-mAspAT).(More)
The precursor protein of pig mitochondrial aspartate aminotransferase (pre-mAspAT) contains a 29-residue presequence (Joh, T., Nomiyama, H., Maeda, S., Shimada, K., and Morino, Y. (1985) Proc. Natl. Acad. Sci. U. S. A. 82, 1-5). Pre-mAspAT produced in an in vitro transcription and translation system was avidly imported into pig and rat liver mitochondria to(More)
In porcine cytosolic aspartate aminotransferase, a dimeric enzyme, the amino-terminal region anchoring onto the neighboring subunit is linked to the adjoining floppy peptide segment (residues 12-47), an integral part of the small domain whose facile movement upon substrate binding is a striking "induced fit" feature of this enzyme. To assess the(More)
A full-length cDNA encoding the pig cytosolic aspartate aminotransferase (EC (cAspAT) was constructed from two overlapping cDNA clones. One clone (Lm pcAAT-8) isolated from a lambda gt10 pig heart cDNA library contained a 3' untranslated sequence, a poly(A) segment, and a part of the coding region for amino acid positions 127-412. Another clone (Lm(More)
The functional roles of Val37 and Gly38 in porcine cytosolic aspartate aminotransferase have been studied in the site-directed mutants V37A, G38A, and G38S where the size and hydrophobic character of these residues has been altered. Previous x-ray studies have shown that Val37 and Gly38, which are part of a flexible loop, interact directly with bound(More)
A protease from Streptomyces violaceochromogenes (Murao, S., Nishino, Y., & Maeda, Y. (1984) Agric. Biol. Chem. 48, 2163-2166) is known to inactivate pig heart aspartate aminotransferase [EC]. Chemical analysis of the core proteins and peptide fragments produced upon proteolysis of the aminotransferase revealed that peptide bond cleavage occurred(More)
Rat liver glutathione S-transferases (RX: glutathione R-transferase, EC were found to adsorb S-carbamidomethyl glutathione linked to Sepharose CL-4B via lysyl or aliphatic diamine spacers of various carbon chain lengths (-NH-(CH2)n-NH-, n = 2, 4, 5, 6, 8 and 10). Proteins were eluted specifically by reduced glutathione. The affinity of the enzymes(More)
Reaction of N-bromosuccinimide with pig heart cytosolic aspartate aminotransferase led to loss of the enzymatic activity. Chemical analysis indicated the modification of two tryptophan residues. At a low ratio of N-bromosuccinimide to enzyme, oxidation of Trp 122 occurred without affecting the enzymatic activity. Increase in the ratio resulted in the(More)