Sequence and domain structure of yeast pyruvate carboxylase.

The nucleotide sequence of the yeast pyruvate carboxylase gene has been determined from a cloned fragment of yeast genomic DNA. The deduced translation product codes for a polypeptide of 1178 amino acids, having a calculated molecular weight of 130,100. The protein shows strong sequence homology to specific regions of other biotin carboxylases, lipoamide transferases, and carbamyl phosphate synthetases. The homologous regions suggest the presence of three subsites in the enzyme: a biotin attachment site, a keto acid-binding site, and an ATP-binding site. Partial proteolysis with a variety of proteases under nondenaturing conditions indicates the presence of structural domains corresponding to these subsites.