%0 Journal Article
%T Cloning and constitutive expression of Deschampsia antarctica Cu/Zn superoxide dismutase in Pichia pastoris
%A Jaime R S¨¢nchez-Venegas
%A Alejandro Navarrete
%A Jorge Dinamarca
%A Le¨®n A Bravo Ram¨ªrez
%A Ana Moraga
%A Manuel Gidekel
%J BMC Research Notes
%D 2009
%I BioMed Central
%R 10.1186/1756-0500-2-207
%X The Copper/Zinc superoxide dismutase (Cu/ZnSOD) gene, SOD gene, was isolated from a D. antarctica by cDNA library screening. This SOD gene was cloned in the expression vector pGAPZ¦ÁA and successfully integrated into the genome of the yeast P. pastoris SMD1168H. A constitutive expression system for the expression of the recombinant SOD protein was used. The recombinant protein was secreted into the YPD culture medium as a glycosylated protein with a 32 mg/l expression yield. The purified recombinant protein possesses a specific activity of 440 U/mg.D. antarctica Cu/ZnSOD recombinant protein was expressed in a constitutive system, and purified in a single step by means of an affinity column. The recombinant SOD was secreted to the culture medium as a glycoprotein, corresponding to approximately 13% of the total secreted protein. The recombinant protein Cu/ZnSOD maintains 60% of its activity after incubation at 40¡ãC for 30 minutes and it is stable (80% of activity) between -20¡ãC and 20¡ãC. The recombinant SOD described in this study can be used in various biotechnological applications.The hairgrass Deschampsia antarctica Desv. is one of the two vascular plants that have adapted to the extreme climate of the Maritime Antarctic [1]. It is tolerant to low temperatures, usually between -2¡ãC and 6¡ãC in summer and freezing in winter [2]. Episodes of high light intensity and increased UV radiation due to the thinning of the ozone layer during spring are frequent in Antarctic [3]. Because of the extreme conditions in which this plant lives, it has attracted the interest of plant physiologists, biochemists and molecular biologists, who are trying to discover the mechanisms that enable it to colonize the Antarctic environment [4-6].It has been determined that the combination of low temperature, high light and UV radiation leads to an increase in the production of reactive oxygen species, such as the superoxide anion, hydrogen peroxide and the hydroxyl radical [7]. The accumulatio
%U http://www.biomedcentral.com/1756-0500/2/207