Proteins Flashcards
What is the central dogma
DNA can replicate itself which produce our genetic codes. DNA then can turn into RNA and then into proteins so proteins are genetically coded.
What is the monomer of proteins
Alpha amino acids
What is required for an organic molecule to become an alpha amino acid
There is a amine group, a carboxyllic acid group, a hydrogen atom and an r group attached to the central alpha carbon.
What is on the left end and what is on the right end on the primary structure of all proteins
Left end - Amino
Right end - Carboxuyllic acid
What are the basic amino acids
Lysine
Arganine
Histidine
What are the acidic amino acids
Aspartic acid
Glutamic acid
What makes a basic side chain
NH3+ ion on the chain
What makes an acidic side chain
O- ion on the chain
What has a H side chain
Glycine
What has a methyl side chain
Alanine
What has a phenyl and methyl side chain
Phenylalanine
What has a phenyl a methyl and a hydroxyl side chain
Tyrosene
What is chirality
Where there are four unique chains on a carbon
What orientation is bacterial amino acids
D amino acids
What orientation is Human amino acids
L amino acids
Why is orientation important for proteins
Proteins are catalyzed by enzymes, which have holes for specific orientations, if you have the wrong orientation it won’t catalyze.
What form do amino acids exist in water
Zwitterions (NH3+ and COO-)
What is amphoteric
Acids and bases simultaneously
Why are amino acids somewhat insoluble water
Because the ions are attracted to each other rather than water
What is the isoelectric point
PH Point where it is least soluble in water, most atoms are zwitterions
What does water do to protein shape
This allows hydrophillic parts of the protein to go near the water and go outside and hydrophobic parts of the protein in the middle
How are proteins polymerised
Through peptide bonds via condensation
Why are peptide bonds inflexible
Because it has a partial double bond configuration
What is a disulphide bond
A covalent bond in between proteins which is forms with oxidation between two cystine amino acids
What holds proteins shape
H bonds, Van Der waals attraction and electrostatic attraction
What is the primary structure
Order of amino acids from the NH3+ end to the O- end
What is secondary structure
Repeating patterns stabilised by weaker bonds
What is tertiary structure
Overall conformation
What is quaternary structure
Interaction of multiple subunits (single chains)
What are alpha helixes and beta pleated sheets stabilized by
H bonds
Why are genetic defects catastrophic
DNA forms proteins and if DNA is defected, then primary structure of protein is changed and then function is changed making the protein do the wrong function
What is a domain
stable substructure of proteins
What is a transmembrane protein
A nonpolar protein that hangs around within the cell membrane
What is a property of beta pleated sheets
High tensile strength, used for silk and spider webs
Do all genetic mutation which change primary structure change function
No
What are the types of disuplhide bridges?
Inter and intrachain
What is a simple protein
Proteins with only amino acids
What is a conjugated protein
Proteins with other stuff as well as amino acids
What is a lipoprotein
Conjugated protein with a lipid
What is a metalloprotein
Conjugated protein with a metal
What is a glycoprotein
Conjugated protein with sugar groups
What is a prosthetic group
A group that isn’t an amino acid in a protein.
What is a coordinate bond
metals can receive 2 electrons from a nonmetal donor which forms a coordinate bond
How are protein relationships detrmined
By similarity of amino acid sequences
What is protein conformation
Protein shape
What does destroying the conformation do to a protein
Denature
How do we denature a protein
By breaking disulphide bridges, hydrogen bonds, van der walls and dipole dipole forces
How do eggs fry
By denaturing ovalbumin
Is denaturing reversible
Probably not, but if it doesn’t change the primary structure yes
How do we break hydrogen bonds, dipole dipole and dispersion bonds
By adding heat or chemicals depeniding on how easy it is to denature
What are the types of proteins
Transport proteins
Storage proteins
Protective proteins
Motile proteins (muscle)
What can H bonds be denatured by
Heating
What can S-S bonds be denatured by
Strong Reducing agents
What can detergents denature
Hydrophobic regions
What influences function
shape
What is an example of a (usually) globular protein
Enzymes
What is something that binds to a protein
Ligand
What are ligands usually bound by
Noncovalent bonds
What does an enzyme do
Enzyme binds specific ligands (substrates). It alters its configuration so it can be converted into a product rapidly
Where does a reaction take place in an enzyme
Active site
How much do enzymes speed up reaction rate
LOTS from twice per minute to hundreds of thausands of molecuels per second
What are metabolic pathways
Chain of reactions catylysed by enzymes
How do you change proteins shape by one simple ion
Adding phosphates
Why are phosphates important for enzymes
Because a phosphate might turn an enzyme on and off by changing the shape.
What is a kinase enzyme
Adds phosphate from enzymes
What is a phosphatase enzyme
Removes phosphate from enzymes
What does enzymes always end with
ASE
What is ligase
Catalyse formation of bonds
What is a polymerase
Catalyze polymerisation reactions
What is a protease
Break peptide bonds in proteins
What is a oxidoreductase
Catalyze redox reactions
what is transferase
Catylyzes transfer of groups
What is a redox reaction
Where electrons transfer
What do electrons usually transfer with in the cell
H or H-
