ISSN:
1432-072X
Keywords:
Sulphate assimilation
;
Uptake kinetics
;
Rhodella
;
Metabolic inhibitors
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Sulphate uptake by the unicellular marine red algaRhodella maculata conforms to Michaelis-Menten kinetics. Two uptake systems have been found: a low affinity system with an apparentK m of 22 mM, and a high affinity system with an apparentK m of 63.4 μM. Transition from the low to the high affinity system can occur within 2.5 min, in response to a decrease in the ambient sulphate concentration to below 10 mM. Assimilation rates in the dark are about 20% those in the light, although enhancement by light is independent of the quanlity of light supplied above 27 μmol m-2 s-1. Use of metabolic inhibitors indicates that photophosphorylation provides the main source of energy for sulphate assimilation, through both cyclic and non-cyclic electron flow.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01054000
Permalink
