Crystallization and Preliminary X-Ray Diffraction Studies of a Psychrophilic Iron Superoxide Dismutase from Pseudoalteromonas haloplanktis
Authors: Merlino, Antonello; Krauss, Irene R.; Castellano, Immacolata; Vendittis, Emmanuele De; Vergara, Alessandro; Sica, Filomena
Source: Protein and Peptide Letters, Volume 15, Number 4, May 2008 , pp. 415-418(4)
Publisher: Bentham Science Publishers
Abstract:The Antarctic eubacterium Pseudoalteromonas haloplanktis (Ph) produces a cold-active iron superoxide dismutase (SOD). PhSOD is a homodimeric enzyme, that displays a high catalytic activity even at low temperature. Using hanging-drop vapour-diffusion technique, PhSOD has been successfully crystallized in two different crystal forms. Both crystal forms are monoclinic with space group P21 and diffract to 2.1 Å resolution. Form I has unit-cell parameters a=45.49Å b=103.63Å c=50.37Å β=108.2° and contains a homodimer in the asymmetric unit. Form II has unit-cell parameters a=50.48Å b=103.78Å c=90.25Å β=103.8° and an asymmetric unit containing two PhSOD homodimers. Structure determination has been achieved using molecular replacement. The crystallographic study of this cold-adapted enzyme could contribute to the understanding of the molecular mechanisms of cold-adaptation and of the high catalytic efficiency at low temperature.
Document Type: Research Article
Publication date: May 2008
- Protein & Peptide Letters publishes short papers in all important aspects of protein and peptide research, including structural studies, recombinant expression, function, synthesis, enzymology, immunology, molecular modeling, drug design etc. Manuscripts must have a significant element of novelty, timeliness and urgency that merit rapid publication. Reports of crystallisation, and preliminary structure determinations of biologically important proteins are acceptable. Purely theoretical papers are also acceptable provided they provide new insight into the principles of protein/peptide structure and function.