It is characterized by particular reactivity to thiol, indole, imidazole, phenolic, thioester and methionyl groups, leading to oxidative damage to the polypeptide chains
and loss of biological function of the proteins [12,13].
These triplets, also called codons, specify the amino acid to be added at the corresponding position along a growing polypeptide chain
. The end result is called the primary transcript.
In order to model quaternary structure, several pencil transferase pipe cleaner models can be bundled together to represent a type of protein composed of several polypeptide chains
whose job is to bind and transport multiple pencils.
A disulfide bridge is a covalent bond between the sulfur atoms of two cysteine residues from different parts of the polypeptide chain
. The residues with disulfide bridges can be located anywhere in the chain, and this cross-linking contributes to the stability of the protein.
The final model consisted of the complete polypeptide chains
of the monomers composed of 434 amino acid residues, two GSH molecules, and 474 water molecules.
This restructuring triggers the relatively tight, parallel, [alpha]-helix form of a polypeptide chain
to lengthen into a more extended, nonparallel, zigzag conformation, thus creating more stable, [beta] pleated sheets.
After mRNA is formed polypeptide chains
are synthesized by translation of the mRNA molecule.
This process of bringing in corresponding amino acids builds the growing polypeptide chain
. Termination of translation occurs when a stop codon (UAA, UAG, or UGA) is reached in the mRNA sequence (Campbell & Reece, 2005).
The students took on character roles of DNA and RNA while acting out complementary base pairing, splicing of introns and joining of exons, matching of mRNA codons to the corresponding amino acids, and assembly of amino acids on a growing polypeptide chain
. At the end, the students were given a short quiz to assess what they had learned and a survey about their satisfaction with the activity.
Much interest centers on the tunnel through which the nascent polypeptide chain
exits, shown to be ~100 [Angstrom] long and up to 25 [Angstrom] wide.
The residues are distant from each other in the amino acid sequence, but because of the folding of the polypeptide chain
, they are adjacent on the antibody's surface.
Mainly, fragment ions result from cleavages between the amino acid residues in the polypeptide chain
. The skill in MS lies in identifying diagnostic peaks in complex spectra with the aid of computer programs.