Search results
Results From The WOW.Com Content Network
The smallest unit forming a homo-oligomer, i.e. one protein chain or subunit, is designated as a monomer, subunit or protomer. The latter term was originally devised to specify the smallest unit of hetero-oligomeric proteins, but is also applied to homo-oligomeric proteins in current literature.
Chemical structure of a polypeptide macromolecule. A macromolecule is a very large molecule important to biological processes, such as a protein or nucleic acid. It is composed of thousands of covalently bonded atoms. Many macromolecules are polymers of smaller molecules called monomers.
In the simplest model of 'nucleated polymerization' (marked by red arrows in the figure below), individual unfolded or partially unfolded polypeptide chains (monomers) convert into a nucleus (monomer or oligomer) via a thermodynamically unfavourable process that occurs early in the lag phase. [56]
According to one definition, a turn is a structural motif where the C α atoms of two residues separated by a few (usually 1 to 5) peptide bonds are close (less than 7 Å [0.70 nm]). [1] The proximity of the terminal C α atoms often correlates with formation of an inter main chain hydrogen bond between the corresponding residues. Such hydrogen ...
In statistical mechanics, the Zimm–Bragg model is a helix-coil transition model that describes helix-coil transitions of macromolecules, usually polymer chains. Most models provide a reasonable approximation of the fractional helicity of a given polypeptide; the Zimm–Bragg model differs by incorporating the ease of propagation (self-replication) with respect to nucleation.
Round rope that gradually flattens out into a thin helical ribbon. Other features Polypeptide direction, NH 2 and COOH termini Small arrows on one or both of the termini, or letters. For β-strands, the direction of the arrow is sufficient. Today, the direction of the polypeptide chain is often indicated by a colour ramp. Disulfide bonds
Levinthal's paradox is a thought experiment in the field of computational protein structure prediction; protein folding seeks a stable energy configuration. An algorithmic search through all possible conformations to identify the minimum energy configuration (the native state) would take an immense duration; however in reality protein folding happens very quickly, even in the case of the most ...
Alpha chain is yellow. Beta and gamma chains are blue. 3D structure of a heterotrimeric G protein Heterotrimeric G protein , also sometimes referred to as the "large" G proteins (as opposed to the subclass of smaller, monomeric small GTPases ) are membrane-associated G proteins that form a heterotrimeric complex.