Scavenging of Reactive Oxygen Species in Vegetative Cells and Protection of Nitrogenase in Heterocysts of the Cyanobacterium Anabaena variabilis ATCC 29413.
Abstract
Nitrogen-fixing cyanobacteria make a significant contribution to the global nitrogen cycle. Symbiotic and free-living marine cyanobacteria probably contribute more to global nitrogen fixation than do all the other nitrogen-fixing bacteria put together. The enzyme for reducing N2 to NH4+ is the nitrogenase. It catalyzes a very reductive reaction, and the reaction is rapidly and irreversibly inactivated by molecular oxygen and reactive oxygen species. In this project the cyanobacterium Anabaena variabilis ATCC 29413 is selected to investigate the role of enzyme systems for scavenging of reactive oxygen species because it belongs to the section of filamentous cyanobacteria that can fix nitrogen within specialized cells, the heterocysts. So it is possible to compare the enzyme system between different cell types, vegetative cells and heterocysts. To shed light on the mechanisms which are important to scavenge reactive oxygen species within a cyanobacterial cell, it is necessary to look for appropriate enzymatic activities, to accumulate the enzymes by protein chemical purification procedures and to characterize them.
Publications
Catalase-peroxidase from synechocystis is capable of chlorination and bromination reactions.
Autoren: Jakopitsch, C; Regelsberger, G; Furtmüller, PG; Rüker, F; Peschek, GA; Obinger, C Jahr: 2001
Journal articles
Cyanobacteria: As "chloromitochondria" - true "green" and "red" paradigms for bioenergetic research
Autoren: Peschek, G. A., Obinger, C. Jahr: 2012
Journal articles
external links and characteristics of the publication:Biochemical characterization of a membrane-bound manganese-containing superoxide dismutase from the cyanobacterium Anabaena PCC 7120.
Autoren: Regelsberger, G; Atzenhofer, W; Ruker, F; Peschek, GA; Jakopitsch, C; Paumann, M; Furtmüller, PG; Obinger, C Jahr: 2002
Journal articles
Project staff
Christian Obinger
Univ.Prof. Mag.rer.nat. Dr.rer.nat. Christian Obinger
christian.obinger@boku.ac.at
Tel: +43 1 47654-10011, 77273
Project Leader
01.12.1999 - 30.11.2001