Cloning and expression of an iron-containing superoxide dismutase in the parasitic protist, Trichomonas vaginalis

摘要

A superoxide dismutase (SOD) gene of the parasitic protist Trichomonas vaginalis was cloned, sequenced, expressed in Escherichia coil, and its gene product characterized. It is an iron-containing dimeric protein with a monomeric mass of 22 067 Da. Southern blots analyses suggested the presence of seven iron-containing (FeSOD) gene copies. Hydrophobic cluster analysis revealed some peculiarities in the 2D structure of the FeSOD from T. vaginalis and a strong structural conservation between prokaryotic and eukaryotic FeSODs. Phylogenetic reconstruction of the SOD sequences confirmed the dichotomy between FeSODs and manganese-containing SODs. FeSODs of protists appeared to group together with homologous proteobacterial enzymes suggesting a possible origin of eukaryotic FeSODs through an endosymbiotic event. (C) 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V. [References: 27]