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11:45
Generation of Marked and Markerless Mutants in Model Cyanobacterial Species
Published on: May 29, 2016
Terminal oxidases of cyanobacteria
S E Hart1, B G Schlarb-Ridley, D S Bendall
1Department of Biochemistry, University of Cambridge, Building O, The Downing Site, Cambridge CB2 1QW, U.K. seh38@cam.ac.uk
Biochemical Society Transactions
|July 27, 2005
Summary
Cyanobacteria possess a branched respiratory chain, distinct from linear types. This review details three terminal oxidases in cyanobacteria, exploring their genetic, biochemical, and physiological roles.
Area of Science:
- Biochemistry
- Microbiology
- Photosynthesis
Background:
- Cyanobacteria exhibit a branched respiratory chain, unlike linear systems.
- Respiratory and photosynthetic electron transfer chains coexist and share components within thylakoid membranes.
Purpose of the Study:
- To review the genetic, biochemical, and biophysical characterization of three terminal respiratory oxidases in cyanobacteria.
- To discuss the interactions of these oxidases with electron donors and their physiological significance.
Main Methods:
- Genetic identification of terminal respiratory oxidases.
- Biochemical characterization of enzyme function.
- Biophysical analysis of enzyme properties.
Main Results:
- Identification of three distinct terminal respiratory oxidases: aa3-type cytochrome c oxidase, cytochrome bd-quinol oxidase, and an alternative oxidase.
- Characterization of their genetic basis, biochemical activities, and biophysical properties.
- Elucidation of their interactions with various electron donors.
Conclusions:
- Cyanobacterial respiration is characterized by a branched electron transport chain.
- The three identified terminal oxidases play crucial roles in cyanobacterial physiology.
- Understanding these oxidases is key to comprehending electron transfer in cyanobacteria.
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