Macromolecules : proteins and nucleic acids Flashcards
What are proteins made of?
Proteins are made up of amino acids, which have the basic structure containing an amino group, a carboxyl group, and a side chain (R group).
What affects the overall property of an amino acid?
The R group.
How are protein polymers formed?
In order to form protein polymers, two amino acids join via a dehydration reaction
An OH from the carboxyl group of one amino acid reactions with an H from an amino group of another amino acid to form a peptide bond between a carbon and nitrogen.
What is a peptide bond?
Bond between carbon and nitrogen to form a polymer of amino acid.
What are the four levels of protein structure?
- Primary structure : is the sequence of amino acids in a polypeptide chain.
- Secondary structure : the coiling or folding of the chain. Divided into alpha helix and beta pleated chain.
- Tertiary structure : is the overall 3 dimensional structure, resulting from the R group interaction.
- Quaternary structure : More than one polypeptide chains together
What holds together each stage of the polypeptide structures?
Primary structure is held by peptide bond, Secondary by hydrogen bonds, and tertairy by the interactions from the R group.
What are the different types of proteins?
- Transport proteins
- Enzyme proteins
- Defense proteins
- Signal proteins
- Reciever proteins
- Contractile proteins
- Structural proteins
(TED SR CUSSED)
Differentiate between transport proteins and enzyme proteins?
Enzymes: catalyze chemical reactions
Usually globular and contain special grooves/pockets to bind their molecule (substrate) of interest
ex : lactase, kinase
Transport proteins: move nutrients, sugar molecules, and important proteins into or out of the cell
Usually embedded in the cell membrane with a hydrophilic core and hydrophobic outside
Ex: aquaporin
What are defense proteins?
Defense proteins: their shape and structure matters. Found often in the blood stream or in tissues as a result of infection, help fight against infections and mobilizing immune responses.
Usually recognize portions of microbes
ex : gramicidin, immunoglobulin
Differentiate between receptor and signal proteins.
Signal proteins: chemical messengers that help coordinate body responses
Usually free molecules (also known as ligands/substrate the thing that binds to something that needs to be carried)
Ex: insulin
Receptor proteins: receive and transmit signals to the rest of the cell
Usually embedded in the cell membrane
Ex: acetylcholine receptor
Differentiate between contractile and structural proteins.
Contractile proteins: make up your tendons, muscles and ligaments
Ex: myosin and actin
Structural proteins: often form long, strong fibers of connective tissue
Ex: collagen, keratin, elastin
How do proteins become non functional?
- If there are mutations in the smino acid sequence
- If the ph or temperature is more than required, it becomes denatured.
What are prions?
Prions are misfolded proteins that can convert other properly folded proteins nearby to misfold (usually in the brain) (cannibalism is the cause)
Ex : mad cow disease in cows, and Creutzfeld-Jakob Disease
What is the primary component of our genetic material?
Nucleic acid
What are nucleotides?
Nucleic acids are also called nucleotides. They consist of nitrogenous case, sugar and phosphate group.
