title: Trypanosoma cruzi oleate desaturase: molecular characterization and comparative analysis in other trypanosomatids.
abstract: Trypanosoma cruzi lipids contain a high content of unsaturated fatty acids, primarily oleic acid (C18:1) and linoleic acid (C18:2). Previous data suggest that this parasite is able to convert oleic acid into linoleic acid; humans are not able to do this. Presently, we show that T. cruzi has a gene with high similarity to the delta12 (omega6)-oleate desaturase from plants. Northern blot analysis of the oleate desaturase gene from T. cruzi (OD(Tc)) indicated that this gene is transcribed in epimastigote, amastigote, and trypomastigote forms. Pulsed-field analysis showed that OD(Tc) is located at distinct chromosomal bands on distinct T. cruzi phylogenetic groups. In addition, the chromoblot analysis demonstrated the presence of homologous OD(Tc) genes in several trypanosomatids; namely, Crithidia fasciculata, Herpetomonas megaseliae, Leptomonas seymouri, Trypanosoma freitasi, Trypanosoma rangeli, Trypanosoma lewisi, Blastocrithidia sp., Leishmania amazonensis, Endotrypanum schaudinni, and Trypanosoma conorhini. The native OD(Tc) activity was detected by metabolic labeling and analysis of total fatty acids from epimastigotes and trypomastigotes of T. cruzi, coanomastigotes of C. fasciculata, and promastigotes of L. amazonensis, H. megaseliae, and L. seymouri. The fact that the enzyme oleate desaturase is not present in humans makes it an ideal molecular target for the development of new chemotherapeutic approaches against Chagas disease.
authors.affiliation: Department of Biological Sciences, University of Texas at El Paso, 500 W. University Ave., El Paso, Texas 79968, USA. ramaldonado@utep.edu
authors.forename: Rosa A
authors.initials: RA
authors.lastname: Maldonado
authors.forename: Renata K
authors.initials: RK
authors.lastname: Kuniyoshi
authors.forename: Jutta G
authors.initials: JG
authors.lastname: Linss
authors.forename: Igor C
authors.initials: IC
authors.lastname: Almeida
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D014355:Chagas Disease / Q000188:drug therapy; D003001:Cloning, Molecular; D016521:Electrophoresis, Gel, Pulsed-Field; D044943:Fatty Acid Desaturases / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D010944:Plants / Q000201:enzymology / Q000235:genetics; D015183:Restriction Mapping; D016415:Sequence Alignment; D017421:Sequence Analysis; D017385:Sequence Homology; D014349:Trypanosoma cruzi / Q000201:enzymology* / Q000235:genetics; D014351:Trypanosomatina / Q000201:enzymology / Q000235:genetics
chemical_list: D044943:Fatty Acid Desaturases; C021904:Phosphatidylcholine desaturase; D044925:Oxidoreductases Acting on CH-CH Group Donors