Escherichia coli and Saccharomyces cerevisiae acetylornithine aminotransferase: evolutionary relationship with ornithine aminotransferase.
Genes argD and ARG8, encoding the acetylornithine aminotransferase (ACOAT) subunit in Escherichia coli and Saccharomyces cerevisiae, respectively, have been cloned and sequenced. The deduced amino acid sequences show substantial similarity. Moreover, they resemble ornithine aminotransferase (OAT) sequences (i.e., those from yeast, rat and man); the observed similarities are statistically significant, indicating that the enzymes are homologous. However, in contrast to OATs, which appear to be substrate (i.e., ornithine)-specific, S. cerevisiae ACOAT transaminates ornithine about as efficiently as E. coli does. The evolutionary relationship between ACOATs and OATs is discussed in terms of substrate ambiguity.
Vrije Universiteit Brussel, Belgium.
H
H
Heimberg
A
A
Boyen
M
M
Crabeel
N
N
Glansdorff
D000595:Amino Acid Sequence; D001120:Arginine / Q000378:metabolism; D001483:Base Sequence; D005075:Biological Evolution; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D011732:Pyridoxal Phosphate / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013379:Substrate Specificity; D000637:Transaminases / Q000235:genetics* / Q000378:metabolism
D011732:Pyridoxal Phosphate; D001120:Arginine; D000637:Transaminases; C018731:acetylornithine transaminase