ArgR-promoter interactions in Corynebacterium glutamicum arginine biosynthesis

作者：Theron Grant; Reid Sharon J^*

来源：Biotechnology and Applied Biochemistry, 2011, 58(2): 119-127.

DOI：10.1002/bab.15

• Corynebacterium glutamicum
• arginine biosynthesis
• ArgR
• arg box-binding motifs

Arginine biosynthesis in Corynebacterium glutamicum is currently poorly understood. A better understanding of its regulation will aid in the engineering of overproducing strains. A transcriptional analysis of the argCJBDFRGH genes and construction of argR deletion mutant confirmed the role of ArgR as a negative regulator of arginine biosynthesis. Increasing the copy number of the argC promoter region caused arginine levels to increase twofold. Electrophoretic mobility shift assays using recombinant ArgR revealed in vitro binding with dissociation constants between 200 and 250 nM to the putative promoter regions of argC and carAB. In contrast, ArgR did not bind in vitro to the putative argG promoter region. Binding of ArgR to the argC and carA promoter regions was prevented by double-stranded competitor oligonucleotides containing motifs resembling the universal ARG box consensus sequence (two in the case of the argC promoter region and one in the case of the carA promoter region). A single ARG box was identified in the carA promoter region. The consensus sequence for the three C. glutamicum ARG box motifs was 5'-HMT GMA TSW ADW WTW TDY-3' and the core sequence (underlined) is well conserved throughout the C. glutamicum genome and located preceding several putative ArgR targets.

• 出版日期2011-4