This site is 100% ad supported. Please add an exception to adblock for this site.

Biochem final 2 N29-


undefined, object
copy deck
what is a syndecan
an intergral membrane proteoglycan
what does the core protein syndecan usually have as its gag chains
3 heparan sulfates
2 chondroitin sulfates
what two types of domains alternate on a heparan gag chain and which one is most important biologially
S domain and the NA domains alternate the S domain is most important biologically
what does an integrin do
mediates a phycical connection between the extra cellular matrix and the cytoskeleton
what is an adhesion protein and give an example
a membrane embedded protein that allows a continum between extracellular matrix and the interior IE Integrins
what is a peptidoglycan
a structural heteropolysaccharide of bacterial cell walls that prevent swelling and osmotic lysis from water
what is the structural components of a peptidoglycan
alternating B1-4 linked N-acetylglucosamine and N-acetlymuramic residues joined by pentaglycine cross linkes
how do antibiotics effect bacterial cell walls
they inactivate the transpeptidases that catalyze the formation of peptide cross links
how do lysozymes in tears and saliva effect the wall of a bacterial cell
they hydrolyze the B1-4 glycosidic bond
what are two important cytoskeleton proteins
actin and spectrin
how are actin and spectrin connected to membrane spanning proteins
by direct interaction or an adaptor protein ankyrin
what are the 3 things that joining of actin and spectrin to transmembrane protiens accomplishes
1. stablizes the membrane against deformation
2. limits the mobility of integral membrane proteins
3. forms corrals that restrict the range of lateal diffusion of membrane lipid molecules
what are the 4 types of adhesion proteins we disscussed
what are the characteristics of an integrin adhesion protein
alpha-beta dimeric heterotypic binding
the binding will be determined by the alpha beta domains
what are the characteristics of an cadherin adhesion protein
homotypic Calcium dependent binding important in embrological development
what are the characteristics of an N-cam adhesion protien
contains immunoglobin like domains and binds hetertypically
what are the characteristics of selectin adheshion protein
contains a lectin domain that binds carbohydrates
what adhesion proteins are involved in recruitment of lymphocytes to and infection or injury
selectin and integrin
what is rolling adhesion
mediated by selectins for an interaction on the endothelial cell walls P-selectins with the glycoprotein ligand for P-selectins on the lymphocyte Process slows molecules down
how do integrins work in recruitment of lymphocytes
the integrin on the endothelial cell interacts with I-cam on the lymphocyte for a tighter adhesion of the lymphocyte (stop part)
what does extravasation
movement of lymphocyte into the inflamation site
What is a membrane raft
a cholesterol-sphingolipid microdomain
these are resistant to detergents
what types of molecule is a lipid bilayer impermeable to
large uncharged polar molecules
charged polar molecules
what types of molecule is a lipid bilayer permeable to
small uncharged polar molecules
what are two types of passive transport
(facilitated diffusion)
channel mediated diffusion (unsaturable)
carrier mediated diffusion (saturable)
what is the purpose of having a protein transportor system
the proteins lower the activation energy by forming non-covalent interactions with the dehydrated solute
what is the main characteristic shared among membrane transportors
that they are a multipass transmembrane protein
what are 3 characteristics about the two state model for transporter function
1. it is energy independent
2. binding and release is concentration driven
3. two forms of the protein exist in thermal dynamic equilibrium
what is Glut 4
a membrane transportor found in muscle and fat cells for the uptake of glucose
how is glucose uptake regulated
insulin "tells" membrane vesicles to fuse with the plasma membrane
2. when glucose is low glut 4 is removed from plasma membrane to a small to large to small vesicle ready to go again
what is an aquaporin
channel protein that is important in RBC's and nephrons to deal with abrupt changes in osmolarity
what is an Ion selective channel
control permeability to ions
these are important in neurons and muscle cells
how do ion channels be selective
the protein contains a backbone of carbonyl oxygens that is specific for certain Ions when they are dehydrated
how does uniport and cotransport differ
uniport= one molecule one direction
cotransport= two molecules involved
1. symport=both same dir
2. antiport= both diff dir
how is secondary active transport driven
driven by an primary active transports electrochemical gradient that works to power a symportor with the second molecule against its gradient
what are some important secondary active transportors in the body
symport=intestinal uptake of glucose/AA
antiport=heart sodium/calcium
what are four types of directly coupled atp-dependent pumps

(primary active transport systems)
ABC transportors
what are three types of F-type atpases and what inhibits these
sodium potassium atpase
sarcoplasmic calcium pump
gastric hydrogen potassium pump
all of these are reversabley phosphoralated

inhibition by vanadate and ouabain
what is an F-type atpase
Atp dependent H+ pumps

these are Atp synthases
what is a V-type atpase
these are proton transporting atpases responsable for acidifing the intracellular comportments (lysosomes ect)
what is an ABC transporter
contains two ATP binding domains
contains two transmembrane pumps to transport junk out of the cell
how is antibiotic resistance accomplised by pathogenic microbes
over activity of the ABC transporters
what is MDR1
an ABC transporter (mulitdrug transporter) that is involved in the developement of resistance to chemotherapy in cancer
what is CFTR
the transmembrane conductance regulator
an ABC family member for CL- ions
this on does NOT!!! require atp. passive
what causes cystic fibrosis
a mutated CFTR
what are some characteristics of the sodium potassium pump
maintain low intracellular Na+ and high intracellular K+
endothermic and electrogenic
how are affinities affected in the sodium potassium pump in relation to what conformation the pump is in
depending on the side of the plamsa membrane the pump is facing, the affinities will be higher to match the ion
what is vanadate and how does it work
a phosphate mimic that inhibits all P-type ATPases at the dephosphoralation step (can't release K+ from protein)
what two inhibitors specifically inhibit the sodium potassium pump
vanadate and oubain
why is oubain uses in heart tissue
oubain inhites the Na+/K+ pump and therefore inhibits secondary active transport(antiport) of Ca++ out of the cell. increase in Ca++, increase contraction strength
oubain is a close relative of what
digitoxin or digoxin
how does oubain differ from a cholesterol
still has steroid backbone, but differs at C17 and has a hexose for a head group
what are the four main roles of sterols
membrane structure
cardiac glycoside (digitoxin, oubain)
emulsifiers (bile acids)
name six steroid hormones
what is the only significant way to rid the body of cholesterols
as bile acids in the feces
what is responsible for making fats accessible to pancreatic lipases
bile acids by acting as emulsifing agents
what is a common bile acid
taurocholic acid
what type of vitamins serve as hormone precursors
A and D
which vitamins are fat soluble and how are they made
A, D, E, K
they are made from isoprenoid compounds
T or F Vitamin D can be made endogenously
what vitamin can function as a hormone and participate in gene regulation
Vit A

also visual pigment in the eye
can be made from B-carotene
what does Vitamin E do
destroys most free radicals
why do we need vitamin K
participates in activation of a blood clotting enzyme (prothrombin)
what does a dolichol do
it is an isoprnoid alcohol that carries sugars during cell wall syn and polysac addition to protiens and lipids
what is the active hormone name for vitamin D3
what two derivities can be formed from B-carotene
retinoic acid (hormone signal to epithel c)
T or F B-carotene and Vitamin A do not contain conjugated double bonds

they do, different from Fatty Acids
what part of vitamin E acts as the anitoxidant
the two ring head structure is where the free radicals are captured
what is warfarin and what does it do
it is a synthetic blood anticoagulant
and is used for prevention of blood clots to reduce the risk of embolism

Deck Info