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Amino acids and proteins

9 videos
1A: We will come to an understanding of the central dogma of molecular biology: DNA makes RNA, and RNA makes protein. You will learn about how we classify the different amino acids and how they come together to form the building blocks of complex proteins.

Central dogma - revisited

VIDEO 6:12 minutes
New discoveries have expanded on or even contradicted the original Central dogma of molecular biology as proposed by Watson and Crick. These discoveries include multiple alternate pathways of the molecules as well as different types of RNA ...

Peptide bonds: Formation and cleavage

VIDEO 7:11 minutes
Peptide bonds are formed when the amine group of one amino acid binds with the carbonyl carbon of another amino acid. We will learn more about peptide bonds and how the cleaving process occurs.  By Tracy Kovach.

Special cases: Histidine, proline, glycine, cysteine

VIDEO 8:18 minutes
Certain amino acids stand out for their unique properties. In this video, you'll learn more about what makes histidine, proline, glycine, and cysteine unique.  By Tracy Kovach.

Amino acid structure

VIDEO 10:55 minutes
In this video, you'll learn about the general structure of amino acids, which include an amine group, a carboxylic acid group, and a unique side chain (R-group) attached to the alpha carbon. In addition, we'll explore where amino acids fit ...

Isoelectric point and zwitterions

VIDEO 5:25 minutes
The isoelectric point of an amino acid is the pH at which the amino acid has a neutral charge. You will learn how to calculate the isoelectric point, and the affects of pH on the amino acid's overall charge. We will also discuss ...

Classification of amino acids

VIDEO 6:06 minutes
Amino acids can be classified according to their side chain's chemical properties (the R-group). This video will show you how! By Tracy Kovach.

Four levels of protein structure

VIDEO 8:49 minutes
The four levels of protein structure are primary, secondary, tertiary, and quaternary. It is helpful to understand the nature and function of each level of protein structure in order to fully understand how a protein works.  By Tracy ...

Conformational stability: Protein folding and denaturation

VIDEO 7:44 minutes
Different bonds/interactions contribute to the stability of each level of protein structure. Let's explore some common ones such as peptide bonds, hydrogen bonds, and disulfide bonds. By Tracy Kovach.