What is the Difference Between Proteinogenic and Non-proteinogenic Amino Acids

Thekey difference between proteinogenic and non-proteinogenic amino acids是蛋白质氨基酸参与蛋白质的产生，而非蛋白质生成氨基酸不参与合成氨基酸。

Proteinogenic amino acids are the amino acids that are incorporated into proteins through the translation process biosynthetically. Non-proteinogenic amino acids are the amino acids that are not naturally incorporated into proteins.

CONTENTS

1.Overview and Key Difference
2.What are Proteinogenic Amino Acids
3.What are Non-proteinogenic Amino Acids
4.Proteinogenic vs Non-proteinogenic Amino Acids in Tabular Form
5.Summary – Proteinogenic vs Non-proteinogenic Amino Acids

What are Proteinogenic Amino Acids?

Proteinogenic amino acids are amino acids that are incorporated into proteins through translation biosynthetically. This term refers to the “protein-creating amino acids”. According to research studies, there are 22 genetically encoded or proteinogenic amino acids. Among them, 20 amino acids are among the standard genetic code, while the other two amino acids are incorporated into proteins through specific mechanisms.

Generally, in eukaryotes, there are only 21 proteinogenic amino acids which include the 20 standard genetic coding amino acids and selenocysteine. Among these amino acids, humans can generate 12 amino acids from each other or from the molecules of intermediary metabolism. However, the rest of the amino acids (9 amino acids) must be taken from outside, usually in their protein-derivative forms. Therefore, these amino acids are known as essential amino acids; this list includes histidine,isoleucine,leucine, lysine,methionine,苯丙氨酸, threonine, tryptophan, and valine.

We can classify these amino acids according to the properties of the end products of the reactions that they take part in. These classes includeglucogenic amino acids, ketogenic amino acids，以及其他可以分解成糖原和生酮产物的氨基酸。

What are Non-proteinogenic Amino Acids?

Non-proteinogenic amino acids are the amino acids that are not naturally incorporated into proteins. These are also namednon-coded amino acids. There are about 140 naturally occurring non-proteinogenic amino acids. These amino acids are important as intermediates in biosynthesis, in the post-translational formation of proteins, in physiological roles, in natural and man-made pharmacological compounds, etc.

Non-proteinogenic amino acids can be natural or synthetic. These amino acids are not naturally encoded or found in the genetic code of living organisms. The most common examples for this kind of amino acid include Ornithine, citrulline, Gamma-aminobutyric acid, etc.

What is the Difference Between Proteinogenic and Non-proteinogenic Amino Acids?

有各种氨基酸，我们可以根据其特性将其分类为各种不同的群。蛋白质生成和非蛋白质生成氨基酸是两种类型的氨基酸。蛋白质原性和非蛋白质生成氨基酸之间的关键区别在于，蛋白质氨基酸参与蛋白质的产生，而非蛋白质生成氨基酸不参与氨基酸的合成。因此，在翻译过程中将蛋白质氨基酸掺入蛋白质中，而非蛋白质生成氨基酸在翻译过程中未掺入蛋白质中。

The following table presents the difference between proteinogenic and non-proteinogenic amino acids in more detail.

Summary – Proteinogenic vs Non-proteinogenic Amino Acids

We can classify amino acids into various different groups according to their properties. The key difference between proteinogenic and non-proteinogenic amino acids is that proteinogenic amino acids are involved in the generation of proteins, whereas non-proteinogenic amino acids are not involved in the synthesis of amino acids.

Reference:

1. “什么是蛋白质氨基酸？”Amino Acid Studies, 7 Apr. 2017.
2. “Proteinogenic Amino Acids.”概述|ScienceDirect主题.

Image Courtesy:

1. “Molecular structures of the 21 proteinogenic amino acids” By Dan Cojocari ✉·✍· – Own work This W3C-unspecified vector image was created with Adobe Illustrator.(CC BY-SA 3.0)via Commons Wikimedia
2. “氨基酸分解代谢修订”米凯尔Haggstrom——通过下议院Wikimedi (CC0)a