amino acidIt refers to the existing amino (- NHtwo）Also containscarboxyl(- COOH)Organic compound。amino acidIt is formed by the substitution of hydrogen which also contains amino groups with other parts of the moleculeImineOfCyclic compound（Subamino acid）。Free amino acids generally refer to amino acids that do not form peptides.The amino group and carboxyl group are bound in the samecarbon atomThe on is calledα - amino acid。Most free amino acids obtained naturally are α - amino acids (R-CHNHtwo－COOH）。
The structure of naturally produced amino acids has the same characteristics:carboxylAdjacencyα—carbon atomThere is an amino acid on it, so it is called α - amino acid.naturalproteinIt is composed of different α - amino acidsPeptide bondCombined complexityPolymer compoundThe structure and composition are very complex.
