ISSN:
1432-072X
Schlagwort(e):
Anabaena cylindrica
;
Molybdenum
;
Vanadium
;
Nitrogenase
;
Ultrastructure
;
Storage Products
;
Heterocyst Frequency
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
Notizen:
Abstract The structural and functional symptoms of molybdenum deficiency inAnabaena cylindrica grown in a medium without combined nitrogen and thus dependent on fixation of elemental nitrogen, resemble those brought about by nitrogen starvation. However, the substantially increased rate of heterocyst differentiation in this culture is not accompanied by a corresponding increase in nitrogenase activity; on the contrary, enzyme activity is severely impaired in the absence of molybdenum. When the supply of molybdenum, or of ammonia, is restored, the alga recovers rapidly. Vanadium exerts an inhibitory effect upon nitrogen-fixing ability of the alga, and its presence in the molybdenum-deficient culture results in the amplification of the symptoms of mlybdenum deficiency.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00696236
