title: Over-expression, purification and functional characterization of Celosia ClpS as a fused protein in Escherichia coli.
abstract: A ClpS homologue from Celosia cristata was expressed as maltose-binding fusion protein under the control of strong inducible tac promoter of pMALc2X vector in TB 1 strain of Escherichia coli. SDS-PAGE analysis showed that fused ClpS is produced as about 63 kDa protein in recombinant bacteria. Expressed product was purified to homogeneity with a yield of about 31 mg/l of bacterial culture. The results indicated that heterologous expression of Celosia ClpS does not affect bacterial growth under different induced conditions. Total cellular antioxidant assessment results revealed that the induction of ClpS activates the bacterial antioxidative system. Since, the purified ClpS did not exhibit antioxidant activity in vitro, we speculated a functional corelation between bacterial protelolytic apparatus and its anti-oxidative system. This prediction may contribute to our better understanding of functional relationship between proteolytic and antioxidative systems in biological worlds in the future investigations.
authors.affiliation: Department of Molecular Biology, Research Institute for Fundamental Sciences (RIFS), University of Tabriz, Tabriz, Iran aghz_bioch@yahoo.co.in
authors.forename: A
authors.initials: A
authors.lastname: Gholizadeh
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D034762:Celosia / Q000737:chemistry* / Q000378:metabolism; D003001:Cloning, Molecular; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D007501:Iron / Q000378:metabolism; D007544:Isopropyl Thiogalactoside / Q000494:pharmacology; D058619:Maltose-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction / Q000187:drug effects*; D018384:Oxidative Stress / Q000187:drug effects; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D014162:Transfection
chemical_list: D000975:Antioxidants; D002352:Carrier Proteins; C454820:ClpS protein, E coli; D029968:Escherichia coli Proteins; D058619:Maltose-Binding Proteins; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D007544:Isopropyl Thiogalactoside; D007501:Iron