期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1991
卷号：88
期号：21
页码：9730-9733
DOI：10.1073/pnas.88.21.9730
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Biotin carboxylase [biotin-carboxyl-carrier-protein:carbon-dioxide ligase (ADP-forming), EC 6.3.4.14 ] is the enzyme mediating the first step of the acetyl-CoA carboxylase [acetyl-CoA:carbon-dioxide ligase (ADP-forming), EC 6.4.1.2 ] reaction. We screened an Escherichia coli DNA library and a DNA fragment carrying the biotin carboxylase gene fabG, and its flanking regions were cloned. The gene for biotin carboxyl carrier protein was found 13 base pairs upstream of the fabG gene. Nucleotide sequencing of the recombinant plasmids revealed that the fabG codes for a 449-amino acid residue protein with a calculated molecular weight of 49,320, a value in good agreement with that of 51,000 determined by SDS/polyacrylamide gel electrophoresis of the purified enzyme. The deduced amino acid sequence of biotin carboxylase is also consistent with the partial amino acid sequence determined by Edman degradation. The primary structure of this enzyme exhibits a high homology with those of other biotin-dependent enzymes and carbamoyl-phosphate synthetase [carbon-dioxide:L-glutamine amino-ligase (ADP-forming, carbamate-phosphorylating), EC 6.3.5.5 ]; therefore, all these enzymes probably function through the same mechanism of reaction.
