Proteins Flashcards
Protein functions
act as catalysts, provide physical stability, recognize and respond to Non self-substances, control physiological responses, respond to chemical signals,
Protein functions part 2
regulate passage of substances across membrane, store amino acids, bind and carry substances, move structures in cell
Protein
amino acids are the monomers, the building blocks of proteins, which have carboxyl and amino groups. polypeptide chains are composed of amino acids, chains folded into specific 3‐D shapes as defined by the amino acid sequence
Structure of amino acids
Central carbon atom
Amino group - basic
Carboxyl group - acidic
R group - side chain, which are variable groups with different functions
Peptide
Amino acids bond together covalently in a
condensation reaction
4 structures of polypeptides
- Primary structure
- Secondary structure
- Tertiary structure
- Quaternary structure
Primary structure
the sequence of amino acids that determines how the protein is folded
Secondary structure
localized regularities of structure
* Repeated spatial patterns in different regions of the
polypeptide chain
* Coils and sheets
Tertiary structure
folding results in specific 3‐D shape of one
polypeptide
* Determined by interactions between R‐groups (e.g., disulfide
bonds, hydrogen bonds)
* Outer surfaces present functional groups that can interact with other molecules
Quaternary structure
overall protein shape due to interaction between multiple polypeptides that make up the functional protein
Denaturation and how it works
protein whose secondary and tertiary structure has been broken down, an example would be using heat to denature proteins
What 2 structures are altered by denaturation
second and tertiary structures
Chaperones and its importance
protect 3‐D structure of other proteins, prevent inappropriate reactions, helps prevent them from binding to other substances
