1.6 - Proteins Flashcards
What are the roles of proteins?
- Structure
- Support
- Protection
- Catalysis (accelerating a chemical reaction)
- Defense
- Regulation
- Movement
- Transport
What determines the function of a protein?
Protein functions are determined by two things:
- Shape of the protein structure
- Sequence of amino acids
How many different types of ‘standard’ human amino-acid monomers exist?
There are 20 different types of amino acid monomers, 9 of which are considered essential (that we cannot create ourselves)
What are proteins responsible for?
Proteins define what an organism is, what it looks like, how it behaves, etc.
- Responsible for most phenotypes
What is a fibrous protein?
A fibrous protein is a protein with a straight structure (amino acids lined up)
What is a globular protein?
A globular protein is a protein with a glob-like structure (amino acids bunched together in a lump)
What is the universal backbone for protein?
NCC
What is a polypeptide?
A polypeptide is a chain of amino acids linked by a strong bond formed when two amino acids join together (peptide bond)
What are radicals?
Radicals are side-chains that branch off of the protein backbone, NCC
What do radicals do?
In amino acids, the special parts (R groups) make each one unique. These R groups decide things like size, charge, and how they interact with other molecules. These differences in R groups are important for shaping how proteins work.
What determines the surface (exterior) chemistry of a protein?
The surface chemistry of a protein is determined by the chemistry of exposed amino-acid R groups
What determines the interior of a protein?
The interior of proteins is held together by R-group-to-R-group and backbone-to-backbone interactions
What is the primary structure of a protein?
The primary structure of the protein is the precise sequence of amino acids. The peptide backbone is repeating units of atoms (N-C-C-N-C-C), but infinite proteins are possible)
There are 20 different possible amino acids, and proteins can have more or less the 100 amino acids. (20^100… you do the math)
In the primary structure, the amino acids are put in their unique sequence
What is the secondary structure of a protein?
The secondary structure is how parts of a peptide fold. It’s mainly influenced by the order of amino acids (the primary structure).
Two common shapes are the alpha helix (like a slinky) and beta-pleated sheets (folded like a fan).
What is the tertiary structure of a protein?
The tertiary structure is the three-dimensional shape of the completed polypeptide. There are multiple R groups present in a folded polymer, and when they interact with one another, the polymer continues folding itself, making a 3D shape.
