Related Experiment Video
Updated: Jul 16, 2026
08:31
Anaerobic Protein Purification and Kinetic Analysis via Oxygen Electrode for Studying DesB Dioxygenase Activity and Inhibition
Published on: October 3, 2018
Oxygen-evolving extrinsic proteins (PsbO,P,Q,R): bioinformatic and functional analysis.
Javier De Las Rivas1, Pedro Heredia, Angel Roman
1Bioinformatics and Functional Genomics Research Group, Instituto de Biología Molecular y Celular del Cáncer (IBMCC, CSIC/USAL) Salamanca, Spain. jrivas@usal.es
Biochimica Et Biophysica Acta
|March 21, 2007
Summary
Photosystem II (PSII) oxygen evolution involves conserved core proteins but divergent extrinsic proteins (OEEps) in plants and algae. Bioinformatics reveals plant-specific OEEps like PsbP, PsbQ, and PsbR are crucial for PSII function.
Area of Science:
- Biochemistry
- Molecular Biology
- Photosynthesis Research
Background:
- Photosystem II (PSII) performs water-splitting and oxygen evolution via a multisubunit complex with intrinsic and extrinsic regions.
- Recent 3D structures reveal the architecture of the oxygen-evolving (OE) center, highlighting conserved core polypeptides but significant changes in extrinsic proteins (OEEps).
Purpose of the Study:
- To investigate the evolutionary divergence of OEEps between prokaryotes and eukaryotes.
- To elucidate the roles of plant-specific OEEps (PsbP, PsbQ, PsbR) in PSII activity and stability.
Main Methods:
- Bioinformatic analysis of OEEp sequences across different species.
- Functional data analysis of OEEp involvement in PSII.
Main Results:
- Plant and green algae OEEps show significant differences compared to prokaryotic counterparts.
- PsbQ exhibits distinct variations between higher plants and green algae.
- A correlation was identified between PsbR and the manganese cluster in the OE center.
Conclusions:
- The evolution of PSII involved significant diversification of extrinsic oxygen-evolving proteins, particularly in plants and algae.
- Plant-specific OEEps (PsbP, PsbQ, PsbR) are essential for full OE center activity and stability, though their precise functions require further investigation.
- PsbR may play a direct role in modulating the Mn cluster.
Related Concept Videos
01:57Gene Families
Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
02:21Globular and Fibrous Proteins
Many proteins can be classified into two distinct subtypes - globular or fibrous. These two types differ in their shapes and solubilities.
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
02:47Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
01:26Oxygenic Photosynthesis
Oxygenic photosynthesis is a fundamental process in which light energy is harnessed to drive the oxidation of water, leading to the production of molecular oxygen (O₂), adenosine triphosphate (ATP), and nicotinamide adenine dinucleotide phosphate (NADPH). This process is essential for sustaining aerobic life on Earth and is primarily carried out by cyanobacteria, algae, and plants. The core of oxygenic photosynthesis lies in the thylakoid membranes, where chlorophyll pigments facilitate light...
01:29Oxygen Requirements and Growth Patterns
Microorganisms exhibit diverse oxygen requirements and growth patterns driven by their metabolic strategies and environmental adaptations. Oxygen, while essential for many organisms, can also be toxic under certain conditions, shaping how microorganisms grow and survive.Oxygen Requirements of MicroorganismsMicroorganisms are classified based on their ability to use or tolerate oxygen:● Obligate aerobes like Mycobacterium tuberculosis need oxygen for energy production, as it serves as the...
01:27Oxygen Transport in the Blood
Hemoglobin (Hb) is a crucial molecule in the human body, consisting of four polypeptide chains, each bound to an iron-containing heme group. This unique structure enables hemoglobin to bind to oxygen, with each molecule capable of combining with four molecules of oxygen, leading to rapid and reversible oxygen loading. When fully loaded with oxygen, it is called oxyhemoglobin, while hemoglobin that has released oxygen is called reduced hemoglobin or deoxyhemoglobin. As hemoglobin binds oxygen,...