alr0882 encoding a hypothetical protein of Anabaena PCC7120 protects Escherichia coli from nutrient starvation and abiotic stresses

作者：Shrivastava Alok Kumar; Pandey Sarita; Singh Prashant Kumar; Rai Snigdha; Rai Lal Chand^*

来源：Gene, 2012, 511(2): 248-255.

DOI：10.1016/j.gene.2012.09.033

• Complementation
• UspA
• RT-PCR
• Western blot
• qRT

This study is the first to demonstrate cloning of alr0882, a hypothetical protein gene of Anabaena PCC7120, its heterologous expression in Escherichia coli strain LN29MG1655 (Delta uspA::Kan) and functional complementation of abiotic stress tolerance of E. colt UspA. The recombinant vector pGEX-5X-2-alr0882 was used to transform Delta uspA E. colt strain. The IPTG induced expression of a 56.6 kDa GST fusion protein was visualized on SDS-PAGE and attested by immunoblotting. E. colt Delta uspA strain harboring pGEX-5X-2-alr0882 when grown under carbon, nitrogen, phosphorus and sulphur limitation and abiotic stresses e.g. nalidixic acid, cycloserine, CdCl2, H2O2, UV-B, phenazine methosulphate (PMS), dinitrophenol (DNP), NaCl, heat, carbofuron and CuCl2 demonstrated about 22.6-51.6% increase in growth over the cells transformed with empty vector. Expression of alr0882 gene in mutant E. coli as measured by semi-quantitative RT-PCR at different time points under selected treatments reaffirmed its role in tolerance against stresses employed in this study. Thus the results of this study vividly demonstrated that the novel protein alr0882, although appreciably different from the known UspA of E. colt, offers tolerance to abiotic stresses hence holds potential for the development of transgenic cyanobacteria.

• 出版日期2012-12-15