PEPTIDE PPT 3

Peptides

These are unbranched chain of amino acids, each joined to the next.

Peptide formation

Under proper conditions, amino acids can bond together to produce a peptide.

Peptide bonds

The bonds that link amino acids together in a peptide chain are called peptide bonds.

Dipeptide

2 amino acids.

Tripeptide

3 amino acids.

Oligopeptide

10-20 amino acid residues.

Polypeptide

More than 20 (long chain).

N-terminal

Always on the left.

C-terminal

Always on the right.

Peptide backbone

The repeating sequence of peptide bonds and α-carbon (-CH) groups - the backbone of the peptide.

R group

The chains that are considered substituents on the backbone rather than part of the backbone.

OXYTOCIN

Regulates uterine contraction and was the first hormone synthesized in the lab used to initiate labor.

VASOPRESSIN

Regulates excretion of water by the kidneys and also affects blood pressure.

VASOPRESSIN

Also known as ADH or antidiuretic hormone.

OXYTOCIN and VASOPRESSIN

Both are produced by the PITUITARY GLAND.

ENKEPHALINS

Produced by the brain and bind to the receptor sites in the brain to reduce pain.

ENKEPHALINS

Responsible for the “WILLPOWER” of athletes.

ENKEPHALINS

Also for the pain-relieving effects of acupuncture.

GLUTATHIONE

Regulation of oxidation-reduction reactions.

GLUTATHIONE

Protects cellular contents from oxidizing agents such as peroxides and superoxides (generated within the cell in response to bacterial invasion).

GLUTATHIONE

The amino acid Glu, is bonded to Cys through the side-chain (-COOH) rather than through its α-carbon (-COOH).