Iron superoxide dismutase (Fe-SOD; EC 1.15.1.1) was isolated from the nitrogen-fixing cyanibacterium Anabaena cylindrical Lemm. Polyacrylamide gel electrophoresis separated the purified protein into three closely running, enzymatically active bands. The molecular weight of the enzyme was estimated by gel filtration to be about 40 kDa. Polyclonal antibodies were produced by immunization of rabbits with the isolated enzyme, and were purified on a column of protein A-Sepharose. The Fe-SOD antibody reacted with the purified Fe-SOD and also specifically recognized the protein in extracts of A. cylindrical. In the extracts, anti-Fe-SOD did not cross-react with Mn-SOD, and enzyme which belongs to an SOD class displaying high homology of primary and three-dimensional structure with respect to Fe-SOD. Irone superoxide dismutase was localized in heterocystis by immunogold labeling and transmission electron microscopy. These results are the first in-situ evidence for the presence of SOD in the cells specialized for nitrogenase activity.
Canini, A., Civitareale, P., Marini, S., Grilli Caiola, M., Rotilio, G. (1992). Purification of iron superoxide dismutase from the cyanobacterium Anabaena cylindrica Lemm. and localization of the enzyme in heterocystsis by immunonogold labeling. PLANTA, 187, 434-444 [10.1007/BF00199961].
Purification of iron superoxide dismutase from the cyanobacterium Anabaena cylindrica Lemm. and localization of the enzyme in heterocystsis by immunonogold labeling
CANINI, ANTONELLA;MARINI, STEFANO;ROTILIO, GIUSEPPE
1992-02-01
Abstract
Iron superoxide dismutase (Fe-SOD; EC 1.15.1.1) was isolated from the nitrogen-fixing cyanibacterium Anabaena cylindrical Lemm. Polyacrylamide gel electrophoresis separated the purified protein into three closely running, enzymatically active bands. The molecular weight of the enzyme was estimated by gel filtration to be about 40 kDa. Polyclonal antibodies were produced by immunization of rabbits with the isolated enzyme, and were purified on a column of protein A-Sepharose. The Fe-SOD antibody reacted with the purified Fe-SOD and also specifically recognized the protein in extracts of A. cylindrical. In the extracts, anti-Fe-SOD did not cross-react with Mn-SOD, and enzyme which belongs to an SOD class displaying high homology of primary and three-dimensional structure with respect to Fe-SOD. Irone superoxide dismutase was localized in heterocystis by immunogold labeling and transmission electron microscopy. These results are the first in-situ evidence for the presence of SOD in the cells specialized for nitrogenase activity.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
