tailieunhanh - Báo cáo khoa học: Elongation of polyunsaturated fatty acids in trypanosomatids

Leishmania majorsynthesizes polyunsaturated fatty acids by using D6,D5 andD4 front-end desaturases, which have recently been characterized [Tri-podi KE, Buttigliero LV, Altabe SG & Uttaro AD (2006)FEBS J273, 271– 280], and two predicted elongases specific for C18D6 and C20D5 poly-unsaturated fatty acids, respectively. | ễFEBS Journal Elongation of polyunsaturated fatty acids in trypanosomatids Veronica I. Livore Karina E. J. Tripodi and Antonio D. Uttaro Institute de Biologia Molecular y Celular de Rosario IBR CONICET Departamento de Microbiologia Facultad de Ciencias Bioquimicas y Farmaceuticas Universidad Nacionalde Rosario Santa Fe Argentina Keywords elongases Leishmania polyunsaturated fatty acids protozoa Trypanosoma Correspondence A. D. Uttaro IBR-CONICET Dpto. Microbiologia Facultad de Ciencias Bioquimicas y Farmaceuticas Universidad Nacionalde Rosario Suipacha 531 2000 Rosario Santa Fe Argentina Fax 54 341 4390465 Tel 54 341 4350661 E-mail toniuttaro@ Received 22 September 2006 revised 6 November 2006 accepted 9 November 2006 doi Leishmania major synthesizes polyunsaturated fatty acids by using A6 A5 and A4 front-end desaturases which have recently been characterized Tri-podi KE Buttigliero LV Altabe SG Uttaro AD 2006 FEBS J 273 271280 and two predicted elongases specific for C18 A6 and C20 A5 polyunsaturated fatty acids respectively. Trypanosoma brucei and Trypanosoma cruzi lack A6 and A5 desaturases but contain A4 desaturases implying that trypanosomes use exogenous polyunsaturated fatty acids to produce C22 A4 fatty acids. In order to identify putative precursors of these C22 fatty acids and to completely describe the pathways for polyunsaturated fatty acid biosynthesis in trypanosomatids we have performed a search in the three genomes and identified four different elongase genes in T. brucei five in T. cruzi and 14 in L. major. After a phylogenetic analysis of the encoded proteins together with elongases from a variety of other organisms we selected four candidate polyunsaturated fatty acid elongases. Leishmania major CAJ02037 T. brucei AaX69821 and T. cruzi XP_808770 share 57-52 identity and group together with C20 A5 polyunsaturated fatty acid elon-gases from algae. The predicted activity was corroborated by functional .