Biochem Flashcards
(39 cards)
Understand the polypeptide bond
repetitive peptide bonds allow for the formation of receptive H bonds and the formation fo the secondary structures
two type of secondary protient structures
alpha helix and beta sheets
Teritary structures
can have both alpha and beta structures
Quaternary structures
When two or more poly peptides form together
Prosthetic group
a non portion component found of some protiens
Mb and Hb
Allosteric regulation for Hb
allosteric meaning other side which is where Hb can attach
A porphyrin ring
has 4 cyclic ring structures
Heme is a ____ w/ a ____ center
porphyrin ring q and a ferrous ion
Hemoglobin(Hb) ____ RBCs
transports O2
Myoglobin(Mb) ___ O2
Storage in the muscles
Proximal histamine
When Heme is w/o O2 then there proximal histamine is attached to Fe
Distal histidine
When the 02 attached to a heme and then attached to another heme
How many bonds can Fe2+ form
6 covalent bonds
How does Fe2+ protected
It is embedded deep w/ in the porphyrin ring and deep in the global protein
Myoglobin has what type of dissociation curve
hyperbolic
Hemoglobin is a ____ if __ polypeptide chains
tetramer and 4
HbA is a pair of identical ___
ab dimmers
4 globin monomers means that ___ O2 molecules can be carried on Hb
4
When Hb is “T” or Taut then the the molecule is
deoxygenated
when the Hb is “R” and relaxed the structure is oxyhemoglobin
Why is histidine used
It helps buffer the pH of the blood as well as regulate the O2 affinity
When O2 binds to heme ring the ring assumes more of a ___ shape
planer. this tugs on the proximal histidine amino acid which tugs on a-helix and changes shape to a globin monomer
What is cooperative ligand binding in association to heme
When one O2 binds then the affinity for O2 increases causing all 4 locations to become oxygenated
Why is O2 a positive allosteric
because binding of 02 at once site increase affinity for o2 at other sites