INVESTIGADORES
TRIPODI Karina Eva Josefina
artículos
Título:
Functional characterization of front-end desaturases from trypanosomatids depicts the first polyunsaturated fatty acid biosynthetic pathway from a parasitic protozoan
Autor/es:
TRIPODI, KARINA; BUTTIGLIERO, L.; ALTABE, S.; UTTARO, A. D.
Revista:
The Febs Journal
Editorial:
Federation of European Biochemical Societies
Referencias:
Año: 2006 vol. 273 p. 271 - 280
Resumen:
A survey of the three kinetoplastid genome projects revealed the presence
of three putative front-end desaturase genes in Leishmania major, one inLeishmania major, one in
Trypanosoma brucei and two highly identical ones (98%) in T. cruzi. The
encoded gene products were tentatively annotated as D8, D5 and D6
desaturases for L. major, and D6 desaturase for both trypanosomes.
After phylogenetic and structural analysis of the deduced proteins, we
predicted that the putative D6 desaturases could have D4 desaturase
activity, based mainly on the conserved HX3HH motif for the second
histidine box, when compared with D4 desaturases from Thraustochytrium,
and two highly identical ones (98%) in T. cruzi. The
encoded gene products were tentatively annotated as D8, D5 and D6
desaturases for L. major, and D6 desaturase for both trypanosomes.
After phylogenetic and structural analysis of the deduced proteins, we
predicted that the putative D6 desaturases could have D4 desaturase
activity, based mainly on the conserved HX3HH motif for the second
histidine box, when compared with D4 desaturases from Thraustochytrium,
D8, D5 and D6
desaturases for L. major, and D6 desaturase for both trypanosomes.
After phylogenetic and structural analysis of the deduced proteins, we
predicted that the putative D6 desaturases could have D4 desaturase
activity, based mainly on the conserved HX3HH motif for the second
histidine box, when compared with D4 desaturases from Thraustochytrium,
L. major, and D6 desaturase for both trypanosomes.
After phylogenetic and structural analysis of the deduced proteins, we
predicted that the putative D6 desaturases could have D4 desaturase
activity, based mainly on the conserved HX3HH motif for the second
histidine box, when compared with D4 desaturases from Thraustochytrium,
D6 desaturases could have D4 desaturase
activity, based mainly on the conserved HX3HH motif for the second
histidine box, when compared with D4 desaturases from Thraustochytrium,
3HH motif for the second
histidine box, when compared with D4 desaturases from Thraustochytrium,D4 desaturases from Thraustochytrium,
Euglena gracilis and the microalga, Pavlova lutheri, which are more
than 30% identical to the trypanosomatid enzymes. After cloning and
expression in Saccharomyces cerevisiae, it was possible to functionally
characterize each of the front-end desaturases present in L. major and
and the microalga, Pavlova lutheri, which are more
than 30% identical to the trypanosomatid enzymes. After cloning and
expression in Saccharomyces cerevisiae, it was possible to functionally
characterize each of the front-end desaturases present in L. major and
Saccharomyces cerevisiae, it was possible to functionally
characterize each of the front-end desaturases present in L. major andL. major and
T. brucei. Our prediction about the presence of D4 desaturase activity in
the three kinetoplastids was corroborated. In the same way, D5 desaturase
activity was confirmed to be present in L. major. Interestingly, the
putative D8 desaturase turned out to be a functional D6 desaturase,
being 35% and 31% identical to Rhizopus oryzae and Pythium irregulare
. Our prediction about the presence of D4 desaturase activity in
the three kinetoplastids was corroborated. In the same way, D5 desaturase
activity was confirmed to be present in L. major. Interestingly, the
putative D8 desaturase turned out to be a functional D6 desaturase,
being 35% and 31% identical to Rhizopus oryzae and Pythium irregulare
D5 desaturase
activity was confirmed to be present in L. major. Interestingly, the
putative D8 desaturase turned out to be a functional D6 desaturase,
being 35% and 31% identical to Rhizopus oryzae and Pythium irregulare
L. major. Interestingly, the
putative D8 desaturase turned out to be a functional D6 desaturase,
being 35% and 31% identical to Rhizopus oryzae and Pythium irregulare
D8 desaturase turned out to be a functional D6 desaturase,
being 35% and 31% identical to Rhizopus oryzae and Pythium irregulareRhizopus oryzae and Pythium irregulare
D6 desaturases, respectively. Our results indicate that no conclusive predictions
can be made about the function of this class of enzymes merely
on the basis of sequence homology. Moreover, they indicate that a complete
pathway for very-long-chain polyunsaturated fatty acid biosynthesis
is functional in L. major using D6, D5 and D4 desaturases. In trypanosomes,
only D4 desaturases are present. The putative algal origin of the
pathway in kinetoplastids is discussed.
6 desaturases, respectively. Our results indicate that no conclusive predictions
can be made about the function of this class of enzymes merely
on the basis of sequence homology. Moreover, they indicate that a complete
pathway for very-long-chain polyunsaturated fatty acid biosynthesis
is functional in L. major using D6, D5 and D4 desaturases. In trypanosomes,
only D4 desaturases are present. The putative algal origin of the
pathway in kinetoplastids is discussed.
L. major using D6, D5 and D4 desaturases. In trypanosomes,
only D4 desaturases are present. The putative algal origin of the
pathway in kinetoplastids is discussed.
D4 desaturases are present. The putative algal origin of the
pathway in kinetoplastids is discussed.