Quaternary Structure §

Group: 4 #group-4

Relations §

• Folding in Biology: The quaternary structure of a protein refers to the arrangement of multiple folded polypeptide chains into a larger complex.
• Proteasomes: Proteasomes, the cellular machinery for protein degradation, have a quaternary structure composed of multiple subunits.
• Structural Stability: Quaternary structure contributes to the overall structural stability and folding of protein complexes.
• Protein Complexes: Quaternary structure refers to the arrangement of multiple protein subunits into a larger complex.
• Transcription Complexes: Transcription complexes, which regulate gene expression, have quaternary structures involving multiple protein subunits.
• Cooperativity: Quaternary structure can exhibit cooperativity, where binding of one ligand affects the affinity for subsequent ligands.
• Amino Acid Sequence: The amino acid sequences of individual subunits influence the quaternary structure of multimeric proteins.
• Hemoglobin: Hemoglobin is a classic example of a protein with quaternary structure, composed of four subunits that bind oxygen cooperatively.
• Molecular Machines: Many molecular machines, such as ribosomes and chaperones, have quaternary structures essential for their function.
• Ribosomes: Ribosomes, the cellular machinery for protein synthesis, have a complex quaternary structure composed of multiple protein and RNA subunits.
• Primary Structure: The quaternary structure involves the assembly of multiple polypeptide chains, each with its own primary structure.
• Allosteric Regulation: Quaternary structure changes can lead to allosteric regulation, where binding of a ligand affects the activity of the protein.
• Chaperones: Chaperone proteins often have quaternary structures that assist in the folding and assembly of other proteins.
• Protein-Protein Interactions: Quaternary structure arises from protein-protein interactions between different subunits.
• Signaling Pathways: Quaternary structure changes in signaling proteins can propagate signals and regulate cellular pathways.
• Enzyme Regulation: Quaternary structure changes can regulate enzyme activity by altering the active site or substrate binding.
• Virus Capsids: Virus capsids, the protein shells that encase viral genomes, often have quaternary structures formed by multiple copies of the same protein subunit.
• Multimeric Proteins: Proteins with quaternary structure are composed of multiple polypeptide chains, known as multimeric proteins.
• Disulfide Bridges: In multimeric proteins, disulfide bridges can also stabilize the quaternary structure by forming covalent bonds between different subunits.
• Protein Folding: The quaternary structure involves the assembly of multiple polypeptide chains into a larger complex.