Chemical Structures and Nomenclature

Amino acids are small organic molecules with the general formula shown in Figure 1.

The central carbon atom in this structure is called the a-carbon, and the amino and carboxyl groups attached to it are known as the a-amino group and the a-carboxyl group, respectively. The R groups of the 20 amino acids that can be incorporated into proteins are shown in Table 1; these R groups give the different amino acids their specific chemical and physical properties.

The a-amino group acts as a weak base and is always protonated at physiological pH; similarly, the a-carboxyl group acts as weak acid and at physiological pH is always ionized. Thus, free amino acids in biological material exist as zwitterions, as shown in Figure 2.

Diet Tweak System

Diet Tweak System

Trying To Lose Weight Can Be Tough. But... Not Losing Weight and Gaining What You Lost Back, Sucks. If you've ever felt that no matter what you do to lose weight nothing seems to work. If you've ever felt that there has got to be some kind of a system or way to lose weight...but just have not found it yet.

Get My Free Ebook


Post a comment