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Updated: Jun 20, 2026

A New Approach for the Comparative Analysis of Multiprotein Complexes Based on 15N Metabolic Labeling and Quantitative Mass Spectrometry
Published on: March 13, 2014
Deg/HtrA proteases as components of a network for photosystem II quality control in chloroplasts and cyanobacteria
Pitter F Huesgen1, Holger Schuhmann, Iwona Adamska
1Department of Plant Physiology and Biochemistry, University of Konstanz, Universitätsstrasse 10, D-78457 Konstanz, Germany.
Abstract:
Organisms that perform oxygenic photosynthesis are subjected to photoinhibition of their photosynthetic function when exposed to excessive illumination. The main target of photoinhibition is the D1 protein in the reaction center of the photosystem II complex. Rapid degradation of photodamaged D1 protein and its replacement by a de novo synthesized functional copy represent an important repair mechanism crucial for cell survival under light stress conditions. This review summarizes the literature on the ATP-independent Deg/HtrA family of serine endopeptidases in cyanobacteria and chloroplasts of higher plants, and discusses their role in D1 protein degradation. We propose that Deg/HtrA proteases are part of a larger network of enzymes that ensure protein quality control, including photosystem II, in plants and cyanobacteria.
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