Kinetics of NH 4 + uptake by the arbuscular mycorrhizal fungus Rhizophagus irregularis
Impacto
Scholar |
Otros documentos de la autoría: Pérez-Tienda, J.; Valderas, A.; Camañes, Gemma; García Agustín, Pilar; Ferrol, N.
Metadatos
Mostrar el registro completo del ítemcomunitat-uji-handle:10234/9
comunitat-uji-handle2:10234/2508
comunitat-uji-handle3:10234/6999
comunitat-uji-handle4:
INVESTIGACIONEste recurso está restringido
http://dx.doi.org/10.1007/s00572-012-0452-0 |
Metadatos
Título
Kinetics of NH 4 + uptake by the arbuscular mycorrhizal fungus Rhizophagus irregularisFecha de publicación
2012-08Editor
Springer-VerlagISSN
0940-6360; 1432-1890Cita bibliográfica
Pérez-Tienda, J., Valderas, A., Camañes, G., García-Agustín, P., & Ferrol, N. (2012). Kinetics of NH 4+ uptake by the arbuscular mycorrhizal fungus Rhizophagus irregularis. Mycorrhiza, 22(6), 485-491.Tipo de documento
info:eu-repo/semantics/articleVersión de la editorial
http://link.springer.com/article/10.1007/s00572-012-0452-0Palabras clave / Materias
Resumen
The kinetics and energetics of 15NH 4 + uptake by the extraradical mycelium of the arbuscular mycorrhizal fungus Rhizophagus irregularis were investigated. 15NH 4 + uptake increased with increasing substrate concent ... [+]
The kinetics and energetics of 15NH 4 + uptake by the extraradical mycelium of the arbuscular mycorrhizal fungus Rhizophagus irregularis were investigated. 15NH 4 + uptake increased with increasing substrate concentration over the concentration range of 0.002 to 25 mM. Eadie–Hofstee plots showed that ammonium (NH 4 + ) uptake over this range was biphasic. At concentrations below 100 μM, NH 4 + uptake fits a Michaelis–Menten curve, typical of the activity of a saturable high-affinity transport system (HATS). At concentrations above 1 mM, NH 4 + influx showed a linear response typical of a nonsaturable low-affinity transport system (LATS). Both transport systems were dependent on external pH. The HATS and, to a lesser extent, the LATS were inhibited by the ionophore carbonylcyanide m-chlorophenylhydrazone (CCCP) and the ATP-synthesis inhibitor 2,4-dinitrophenol. These data indicate that the two NH 4 + transport systems of R. irregularis are dependent on metabolic energy and on the electrochemical H+ gradient. The HATS- and the LATS-mediated 15NH 4 + influxes were also regulated by acetate. This first report of the existence of active high- and low-affinity NH4+ transport systems in the extraradical mycelium of an arbuscular mycorrhizal fungus and provides novel information on the mechanisms underlying mycosymbiont uptake of nitrogen from the soil environment. [-]
Publicado en
Mycorrhiza (2012), 22(6), 485-491Derechos de acceso
© Springer, Part of Springer Science+Business Media
http://rightsstatements.org/vocab/InC/1.0/
info:eu-repo/semantics/restrictedAccess
http://rightsstatements.org/vocab/InC/1.0/
info:eu-repo/semantics/restrictedAccess
Aparece en las colecciones
- CAMN_Articles [566]