Proline racemases: insights into Trypanosoma cruzi peptides containing D-proline
Mem. Inst. Oswaldo Cruz
; 104(supl.1): 295-300, July 2009. ilus, tab, graf
Article
em En
| LILACS
| ID: lil-520892
Biblioteca responsável:
BR1.1
ABSTRACT
Trypanosoma cruzi proline racemases (TcPRAC) are homodimeric enzymes that interconvert the L and D-enantiomers of proline. At least two paralogous copies of proline racemase (PR) genes are present per parasite haploid genome and they are differentially expressed during T. cruzi development. Non-infective epimastigote forms that overexpress PR genes differentiate more readily into metacyclic infective forms that are more invasive to host cells, indicating that PR participates in mechanisms of virulence acquisition. Using a combination of biochemical and enzymatic methods, we show here that, in addition to free D-amino acids, non-infective epimastigote and infective metacyclic parasite extracts possess peptides composed notably of D-proline. The relative contribution of TcPRAC to D-proline availability and its further assembly into peptides was estimated through the use of wild-type parasites and parasites over-expressing TcPRAC genes. Our data suggest that D-proline-bearing peptides, similarly to the mucopeptide layer of bacterial cell walls, may be of benefit to T. cruzi by providing resistance against host proteolytic mechanisms.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
LILACS
Assunto principal:
Trypanosoma cruzi
/
Proteínas de Protozoários
/
Isomerases de Aminoácido
Idioma:
En
Revista:
Mem. Inst. Oswaldo Cruz
Assunto da revista:
MEDICINA TROPICAL
/
PARASITOLOGIA
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
França
País de publicação:
Brasil