Open AccessProtein structure of pig liver 4‐aminobutyrate aminotransferase and comparison with a cDNA‐deduced sequence
Author(s) -
BIASE Daniela,
MARAS Bruno,
BOSSA Francesco,
BARRA Donatella,
JOHN Robert A.
Publication year - 1992
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1992.tb17193.x
Subject(s) - complementary dna , peptide sequence , biology , sequence (biology) , biochemistry , nucleic acid sequence , sequence analysis , amino acid , protein sequencing , microbiology and biotechnology , consensus sequence , guanine , cytosine , aspergillus nidulans , dna , gene , nucleotide , mutant
The amino acid sequence of pig liver 4‐aminobutyrate aminotransferase has been determined by gas‐phase sequencing of proteolytically derived peptide fragments. The sequence differs substantially from that predicted for the same enzyme on the basis of the sequence of cDNA derived from pig brain in recently published work [Kwon, O., Park, J. & Churchich, J. E. (1992) J. Biol. Chem. 267 , 7215–7216]. Apart from a few minor differences, the two sequences are completely different in the segment of protein comprising the 36 residues at positions 107–142. Insertion of a cytosine between bases 402 and 403 in the cDNA sequence, together with deletion of the guanine at position 510, results in a DNA sequence which predicts exactly the amino acid sequence determined by peptide analysis in the present work. The mammalian enzyme has approximately 44% sequence identity with the same enzyme from two unicellular eukaryotes ( Saccharomyces cerevisiae, Aspergillus nidulans ) and 22% identity with that from Escherichia coli .