From the perspective of contemporary organic chemistry, peptides are a class of chemical substances with 2-50 amino acids linked by peptide bonds. The amino group of an amino acid is condensed with the carboxyl group of another amino acid, and the amide bond converted into a molecule of water is called peptide bond: where is amide bond, namely peptide bond.
Long chains composed of peptide bonds are called peptide chains: peptides composed of two amino acid molecular structures are called dipeptides; peptides composed of three amino acid molecular structures are called tripeptides; peptides composed of three amino acid molecular structures are called peptides.
The amino acid molecular structure in the peptide chain, that is, the constituent module of several amino acid molecular structures after dehydration and condensation, is called amino acid residues: R1, R2…… The main chain. “On each side of the peptide chain there are a discrete amino (-NH 2) and carboxyl (-COOH) groups, called the ammonia and carboxylic ends, respectively.”
The nicknames of peptides are very complex, and they are generally named after amino-terminal amino acid residues at the beginning, which are called aminoacyl aminoacyl… An amino acid, such as alanine, leucine, glycine and serine composed of a tetrapeptidase, called alanphthalide leucine glycylserine, its chemical structure formula is: because the chemical structure of the peptide is very complex, for simple consideration, the common amino acid abbreviation mark to replace the chemical structure.
“For example, alanine, leucine, glycine, and serine are labeled Ala, Leu, Gly, and Ser, respectively, and alanyl-leucine glycylserine can be indicated by Ala-Leu-Gly-Ser.” The chemical structure of peptide and protein is the same, it is the molecular structure of amino acids linked according to the peptide bond. The difference is that the molecular structure of protein is large, and the molecular structure of peptide is small. However, there is no significant boundary between proteins and peptides. Peptides with more than 50 amino acid residues are generally called proteins, and those with less than 50 amino acid residues are called peptides. Insulin, for example, has 51 amino acid residues and is generally considered the least abundant protein.
Serum albumin is not a complex protein, However, its molecular structure already contains 15 glycine, 45 valine, 58 leucine, 9 isoleucine, 31 proline, 33 phenylalanine, 18 tyrosine, one tryptophan, 22 serine, 27 threonine, 16 cystine, 4 cysteine, 6 methionine, 25 arginine, 16 histidine, 58 “A lysine, 46 asparagine, and 80 glutamic acid residue, is a protein composed of 18 amino acids, with a formula amount of about 69000.”
If the marker is used to mean serum albumin, it can be written: The digital technology in the formula Gly15-Val45-Leu58-Ile9-Pro31-Phe33-Tyr18-TrP1-Ser22-Thr27-Cy16-Cys4-Met6-Arg25-His16-Lys58-Asn46-Glu80 marked at the lower right indicates amino acid residues The number of bases.
Post time: May-06-2025