Bacterial type I glutamine synthetase of the rifamycin SV producing actinomycete, Amycolatopsis mediterranei U32, is the only enzyme responsible for glutamine synthesis under physiological conditions |
| |
Authors: | Peng Wen-Tao Wang Jin Wu Ting Huang Jian-Qiang Chiao Jui-Shen Zhao Guo-Ping |
| |
Affiliation: | 1.Laboratory of Molecular Microbiology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China; 2.Department of Medicinal Chemistry, School of Pharmacy, Fudan University, Shanghai 200032, China; 3 State Key Laboratory of Genetic Engineering/Department of Microbiology, School of Life Science, Fudan University, Shanghai 200433, China; 4.Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai 201203, China |
| |
Abstract: | The structural gene for glutamine synthetase, glnA, from Amycolatopsis mediterranei U32 was cloned via screening a genomic library using the analog gene from Streptomyces coelicolor. The clone was functionally verified by complementing for glutamine requirement of an Escherichia coli glnA null mutant under the control of a lac promoter. Sequence analysis showed an open reading frame encoding a protein of 466 amino acid residues. The deduced amino acid sequence bears significant homologies to other bacterial type I glutamine synthetases, specifically, 71% and 72% identical to the enzymes of S. coelicolor and Mycobacterium tuberculosis, respectively. Disruption of this glnA gene in A. mediterranei U32 led to glutamine auxotrophy with no detectable glutamine synthetase activity in vivo. In contrast, the cloned glnA gene can complement for both phenotypes in trans. It thus suggested that in A. mediterranei U32, the glnA gene encoding glutamine synthetase is uniquely responsible for in vivo glutamine synthesis under our laboratory defined physiological conditions. |
| |
Keywords: | glnA glutamine synthetase Amycolatopsis mediterranei rifamycin SV |
本文献已被 维普 PubMed 等数据库收录! |
|