title: alr0882 encoding a hypothetical protein of Anabaena PCC7120 protects Escherichia coli from nutrient starvation and abiotic stresses.
abstract: 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 (∆uspA::Kan) and functional complementation of abiotic stress tolerance of E. coli UspA. The recombinant vector pGEX-5X-2-alr0882 was used to transform ∆uspA E. coli strain. The IPTG induced expression of a 56.6kDa GST fusion protein was visualized on SDS-PAGE and attested by immunoblotting. E. coli ∆uspA strain harboring pGEX-5X-2-alr0882 when grown under carbon, nitrogen, phosphorus and sulphur limitation and abiotic stresses e.g. nalidixic acid, cycloserine, CdCl(2), H(2)O(2), UV-B, phenazine methosulphate (PMS), dinitrophenol (DNP), NaCl, heat, carbofuron and CuCl(2) 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. coli, offers tolerance to abiotic stresses hence holds potential for the development of transgenic cyanobacteria.
authors.affiliation: Molecular Biology Section, Laboratory of Algal Biology, Center of Advanced Study in Botany, Banaras Hindu University, Varanasi-221005, India.
authors.forename: Alok Kumar
authors.initials: AK
authors.lastname: Shrivastava
authors.forename: Sarita
authors.initials: S
authors.lastname: Pandey
authors.forename: Prashant Kumar
authors.initials: PK
authors.lastname: Singh
authors.forename: Snigdha
authors.initials: S
authors.lastname: Rai
authors.forename: Lal Chand
authors.initials: LC
authors.lastname: Rai
mesh_terms: D017033:Anabaena / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015153:Blotting, Western; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism*; D005798:Genes, Bacterial; D016133:Polymerase Chain Reaction; D013312:Stress, Physiological
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers