PROTEINS Flashcards
a naturally-occurring, unbranched polymer in which the monomer units are amino acids
protein
average nitrogen content of proteins _____ BY MASS
15.4%
contains one peptide chain
Monomeric
contains more than one peptide chain
Multimeric
A protein in which only amino acid residues are present
-Composed of amino acids without prosthetic groups
Simple proteins
A protein that has one or more non-amino acid entitles (prosthetic groups) present in its structure
Conjugated protein
bonds that connect on amino acid to another is known as
amide / peptide bonds
structure of protein refers to the order in which amino acids are linked together in a protein
Primary structure
He sequenced and determined the primary
structure for the first protein - Insulin
Frederick Sanger
- Arrangement of atoms of backbone in space.
- The two most common types : alpha-helix (a-helix) and the beta-pleated
sheet (b-pleated sheet). - Determines interaction of adjacent amino acids
SECONDARY STRUCTURE
A single protein chain adopts a
shape that resembles a coiled spring
Alpha-helix (a-helix)
- Completely extended
amino acid chains
Beta-pleated sheets
- The overall three-dimensional shape of a protein
- Results from the interactions between amino acid side chains (R groups) that are widely separated from each other.
TERTIARY STRUCTURE
covalent, strong, between two cysteine groups
Disulfide bond
Salt Bridge between charged side chains of acidic and
basic amino acids
Electrostatic interactions
acidic and/or basic R groups
H-Bonding between polar