The enzymes involved in synthesis and utilization of carbamylphosphate in the deep-sea tube worm Riftia pachyptila

Simon, V; Purcarea, C; Sun, K; Joseph, J; Frebourg, G; Lechaire, JP; Gaill, F; Herve, G

Abstract

The obligate symbiosis of the deep-sea tube worm Riftia pachyptila with a sulphur-oxidizing bacterium raises important questions concerning its metabolism and metabolic exchanges. In this study, the presence and properties of the enzymes synthesizing and utilizing carbamylphosphate in the arginine and pyrimidine nucleotide pathways were investigated in this worm. The results show that the ammonium-dependent carbamylphosphate synthetase and ornithine transcarbamylase, enzymes involved in the arginine pathway, are present in all body parts of the worm. In contrast, the glutamine-dependent carbamylphosphate synthetase and aspartate transcarbamylase, enzymes involved in the de novo pathway for pyrimidine nucleotides biosynthesis, are present only in the trophosome, the symbiont-harbouring tissue. Although the bacterial nature of these enzymes is not unambigously established, these results strongly suggest that the de novo biosynthesis of pyrimidine nucleotides is limited to the trophosome, the organ where the production of metabolic energy takes place, while the other parts of the worm's body rely on the salvage pathway for the production of the pyrimidine triphosphate nucleotides.

Más información

Título según WOS: ID WOS:000085966300014 Not found in local WOS DB
Título de la Revista: MARINE BIOLOGY
Volumen: 136
Número: 1
Editorial: SPRINGER HEIDELBERG
Fecha de publicación: 2000
Página de inicio: 115
Página final: 127
DOI:

10.1007/s002270050014

Notas: ISI