MGD Flashcards
When pH>pK which form of an acid forms the dominant?
De protonated
Define pK
The stronger the tendency of an acid to dissociate, the lower the pK value
When pH<pK which for of an acid takes the dominant?
Protonated
What are the 3 classes of amino acids based upon charge?
Nonpolar hydrophobic
Polar, uncharged, hydrophilic,
Polar, charged, hydrophilic,
What are the 2 classes of amino acids based upon structure? Give an example of each
Ring = Aromatic eg tyrosine
Without a ring = aliphatic eg lysine
Give 2 examples of positively charged amino acids.
Lysine, Arginine, Histadine.
Give 2 examples of negatively charged amino acids.
Aspartate, glutamate.
Give an example of a non polar amino acid.
Valine
Give an example of a polar, uncharged amino acid.
Serine
Define pI
The isoelectric point
pH at which the protein has no overall charge.
Which type of charge is dominant in amino acids making up an acidic protein?
Negative. Low pI
Which type of charge is dominant in amino acids that form a basic protein?
Positive. High pI
What type of bond forms between two amino acids?
Peptide bond
When drawing a polypeptide, what orientation is it drawn?
Trans, hence Carbonyl O and amine H are on opposite sides.
What is an amyloidose?
Improper folding of tertiary structure of proteins.
What is the name when the polypeptides are the same in quarternary strucure?
Homomeric
What is the name when the polypeptides are different in quarternary strucure?
Heterogenous
What type of structure is found in fibrous proteins?
Repeating primary structure.
What types of proteins have several secondary folding structures?
Globular
What is the pitch and number of amino acids per turn of an alpha helix of a polypeptide. Which direction does it turn?
0.54nm
3.6 amino acids per turn
Right hand
What type of amino acid acts as a helix fixer? Eg?
Small hydrophobic amino acids, eg Ala + Leu
Which two amino acids act as helix breakers and why?
Pro - no rotation around N-C
Gly - small R group supports other conformations
What are the two states of deoxyhaemoglobin? Which has the higher affinity for oxygen?
The tense and relaxed state.
R state has a higher affinity for oxygen
What is the full name for BPG?
2,3 bisphosphoglycerate.