title: Expression, purification, and functional analysis of novel RelE operon from X. nematophila.
abstract: Bacterial toxin-antitoxin (TA) complexes induce programmed cell death and also function to relieve cell from stress by various response mechanisms. Escherichia coli RelB-RelE TA complex consists of a RelE toxin functionally counteracted by RelB antitoxin. In the present study, a novel homolog of RelE toxin designated as Xn-relE toxin from Xenorhabdus nematophila possessing its own antitoxin designated as Xn-relEAT has been identified. Expression and purification of recombinant proteins under native conditions with GST and Ni-NTA chromatography prove the existence of novel TA module. The expression of recombinant Xn-relE under tightly regulated ara promoter in E. coli Top 10 cells confirms its toxic nature in endogenous toxicity assay. The neutralization activity in endogenous toxicity assay by Xn-relEAT antitoxin confirms its antidote nature when studying the whole TA operon under ara regulated promoter. This study promotes newly discovered TA module to be regarded as important as other proteins of type II toxin-antitoxin system.
authors.affiliation: Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, 303 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA ; School of Biotechnology, Gautam Buddha University, Greater Noida, Yamuna Expressway, Uttar Pradesh 201312, India.
authors.forename: Jitendra Singh
authors.initials: JS
authors.lastname: Rathore
authors.affiliation: School of Biotechnology, Gautam Buddha University, Greater Noida, Yamuna Expressway, Uttar Pradesh 201312, India.
authors.forename: Lalit Kumar
authors.identifier: 0000-0002-6606-4408
authors.initials: LK
authors.lastname: Gautam
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D009876:Operon; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D020593:Xenorhabdus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins