Molecular cloning and in vivo expression of a precursor to rat mitochondrial aspartate aminotransferase.
A 2.4 kilobase cDNA for rat mitochondrial aspartate aminotransferase (E.C. 2.6.1.1.) was isolated and sequenced. The predicted presequence is 93% homologous to the presequences of the enzyme from pig and mouse. The predicted amino acid sequence of the mature enzyme differs from that determined directly by amino acid sequencing (Huynh, Q.K., Sakakibara, R., Watanabe, T., and Wada, H. (1981) J. Biochem. (Tokyo) 90, 863-875) at 13 amino acids residues. The most important difference is at position 140 where the cDNA encodes a tryptophanyl residue rather than the previously reported glycine. This critical residue is now seen to be conserved in all aspartate aminotransferases. The coding region of this cDNA was inserted into the plasmid cloning vector pKK233-2 and used to stably express an unfused precursor in Escherichia coli JM105.
Mattingly
J R
JR
Division of Molecular Biology and Biochemistry, School of Basic Life Sciences, University of Missouri-Kansas City 64110.
Rodriguez-Berrocal
F J
FJ
Gordon
J
J
Iriarte
A
A
Martinez-Carrion
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001219:Aspartate Aminotransferases / Q000096:biosynthesis / Q000235:genetics*; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D008930:Mitochondria, Liver / Q000201:enzymology; D008969:Molecular Sequence Data; D011498:Protein Precursors / Q000096:biosynthesis / Q000235:genetics*; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis
D011498:Protein Precursors; D011994:Recombinant Proteins; D004247:DNA; D001219:Aspartate Aminotransferases