Is plant biotin holocarboxylase synthetase a bifunctional enzyme?
Is plant biotin holocarboxylase synthetase a bifunctional enzyme?
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DOI：
10.1016/s0764-4469(00)01223-3
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发表时间：
2000-08-01
期刊：
影响因子：
--
通讯作者：
Alban, C
中科院分区：
文献类型：
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作者：
Alban, C
Holocarboxylase synthetases (HCSs) catalyse the biotinylation of biotin-dependent carboxylases in both prokaryotes and eukaryotes. In Escherichia coli and Bacillus subtilis, the protein also acts as a transcriptional repressor that regulates the synthesis of biotin. Previously, we isolated and characterized a cDNA encoding an Arabidopsis thaliana HCS and subsequently assigned this enzyme form to the chloroplast compartment. To investigate whether or not the Arabidopsis protein may function as a regulator in E. coli, we have expressed the functional plant HCS in a birA-derepressed mutant strain of E. coli devoid of the corresponding E. coli protein and carrying a promoter-less LacZ gene marker inserted into the biotin operon, such that the bio promoter drives the synthesis of beta-galactosidase. Our data demonstrate th at although the expressed plant HCS efficiently complemented the function of apo-carboxylase biotinylation in E. coli, it proved unable to regulate the expression of the biotin biosynthetic genes. (C) 2000 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.
