test 3: lipids Flashcards
what is a lipid
: A hydrophobic biological substance that is has a much higher affinity for an organic solvent than for water
many biological lipids are what
ampipathic
what is the 1st class of lipids
fatty acids
how many carbons are in a long chain oc carboxulic acids
even number maybe 40
what does it mean to be saturated
no double bonds
ex: steric acid
what does unstaturated mean
has double bonds
example: oleic acid
the double bonds are in what confirmation
cis
what is the 2nd class of lipids
biologic. waxes
what are waxes
nonpolar esters of fatty acids and long chain alcohols.
how to make a wax
alcohol + acid = ester
example of a biolog. wax
beeswax
what is the 3rd class of lipids
triaglyceralds (TAGS)
what is TAG made from
esterification of 3 fatty acids + glucerol
what charge does TAG have
neutralized = completey hydrophobic
what is considered a nutriionla fat
triglyceride
how to name fatty acids
delta nomenclature is carboxyl C gets
- indicate the # of double bonds after colon
- indicate location of DB from head w/ greek Delta
omega nomenclature
- everything is the same but the location of the db from the tail end
what atre TAGS stored with
lipases
what do lipases do
break tag ester bonds
get energy though glycolysis and TCA
what are some advantages relative to carbs
more energy 9 Kcal compated to 4 Kcal for carbs
- also have insultation
where do TAGS store water
in adipocytes
what are some disadvantages relative to carbs with TAGS
- take longer to access the stored energy
what is saponification
chemical process of turning fats or oils into soap and glycerol and treating them with a strong base like NaOH or Potassium KOH
what formation is entropically driven
micelle formation
what is the 4th class of lipids
glycerophospholipids
what is another name for glycerophospholipids
phosphoglycerides
in phoshphoglycerides what carbon is chiral
C2
what carbon is esterified to saturated fatty acids
c1
what carbon is esterified to unsaturated fatty acids
c2
what structure is this
phosphoglyceride
what are glycerophospholipids
like triaglyercols but have a c3 phosphoester instead of acyl ester
what is the simplest glyceophospholipid
x=h= phosphatidic acid
what are the 3 common glycerophospholipids
- phosphatidylcholine
- phosphotidylethanolamine
- phosphotidylserine
what is another name for phosphatidyl choline
lecithin
what structure is this
phosphatidyl serine
what is this
phosphatidyl choline
what is this
phosphatidyl ethanolamine
what structure is this
lecithin or phosphatidylcholine
what is the name of a lung surfactant
dipalmitoulphosphatidulcholine (DPP)
where is DPP esterified
- palmatic acid esterified to c1 and c2
what is the role of DPP
- lung surfactant
- decreases the surface tension of liquid coating the alveoli
- prevents them from collapsing due to surface tension of water
what is ether glycerophospholipids
have ether at group at c-1
where is ether glycerophospholipid found
platelet activated factor
what is PAF
- short acetate chain at c-2
- potent and versitile biochemical signal molecule
how was PAF identified
ability to cause platelet aggregation
what is the head group of PAF or ether glycerophospholipids
choline
what is another ether glycerophospholipid
plasmalogens
describe the ethers in plasmalogens
- cis
- alpha,beta unsaturated ether
what is the headgroup for plasmalogens
- phosphoserine
- phosphocholine
phosphoethanolamine
are glycerophospholipids amphipathic
yes they have a polar head and two non polar tails
two tailed lipids form what
bilyaer membrane
one tailed lipid makes what
micelles
what structure is this
Na palmitate
what structure is this
bilayer vesicle
what is a liposome
artifiical bilayer vesciles
what are liposomes made from
glycerophospholipid
what is the function of liposome
delivery vehicle
- used to get hydrophillic drugs into cells (doxorubican)
what is a sphingosine
18 carbon amino alcohol
sphingosine a fatty
amine
what structure is this
sphingosine
what is the 5th class of lipids
sphingolipids
what db confirmation is present on sphingosine
trans
what is the a sphingolipid
lipids made out of sphingosine
is the FA attached satured or non saturared on a sphingolipid
saturated meaning no DB
what are the different names of sphingolipids
- ceramide
-sphingomyelin - cebroside
- globoside
- ganglioside
how is the sugar linked to the ceramide
B- glycosidic bond
what acid is considreed a sphingolipid
sialic acid
what do sphingomyelins contain
contain phosphocholine (shown) or phosphoethanolamine as their polar head group
what structure is this
gangliosides
gangliosides contain what
at least one sialic acid residue that gives them -ve charge
what are cell membrane carbs attatched to
are attached to cell membrane proteins (glycoproteins
- cell membrane lipids (glycolipids)
where do cell membrane carbs face
outside of the cell
in animal cells what is the cell membrane carb called
glycocalyx
how do cell mem. carbs mediate cell-cell interactions
function in cell-to-cell recognition/ interaction / adhesion
what else do cell mem carbs do
serve at attachment points for bacteria, viruses, toxins, signaling hormones
describe how a flu infection works
For a flu virus to penetrate the cells of the respiratory tract,
its thorn-like hemagglutinin molecules have to dock to N-acetylneuraminic acid (sialic acid) molecules on the surface of the host cell
causing the host cell to ingest the virus
what defines blood type
carb patterns of certain sphingolipids and glycoproteins
what breaks down sphingolipids
catabolic enzymes
how can disease in sphingolipids happen
when there is an absence of one enzyme bc it can lead to the accumulation of gangliosides in the cell
what is an example of a disease that is formed from ganglioside accumulation
tay sachs
what does a defect in hexoaminadase lead to
buildup of ganglioside GM2 in nerve killing cells; killing the
what is the 6th class of lipid
terpenoids
what are terpenoids or isoprenoids
lipids built from isoprene units
how many carbons does isoprene have
5
2 isoprenes =
terpene
what are complex terpenoids bult from
multiple isoprene
what produces terpenes
wide variety of plants and some insects
what are archael cell membranes
built from glycerophospholipids with isoprenoid tails and ether linkages
what vitamins are isoprenoids
ADEK which are fat soluble
what are vitamins
compounds that are essential to the health of humans and other vertebrates
squalene cyclization =
steroid nulceus backbone
what is a squalene
triterpene
are steroids terpenoids
yes
how can you form an epoxide from squalene
enzyme catalyzed addition of oxygen atom
where are steoids most present
euk cells
what is a steroid characterized by
- steroid nucleus
- 4 fused rings: 3 6ix membered rings in fixed chair conform, one 5 membered ring fused together
what is an example of a steroid
cholesterol
are the cholesterol rings planar
yes
what is the most common steroid in animals
cholestoerol and its a pre
what structure is this
steroid
what do steroid homones do in animals
including salt balance, metabolic function and sexual function
what is a steroid that regulates glucose metabolism and is in control of inflammation
cortisol or glucosortisoud
what are the names of the sex steroids
progresterone
androstenedione
what signaling are steroid apart of
endocrine meaning they are secreted by glands and are carried through the bloodstream
lipid soluble steroids
receptors are cytoplasmic
bacteria can’t synthesize what
steroids
what does vitamin D3 regulate
ca+2 metabolism
bone growth and repaur
what are bile acids
oxidaive derivatives of cholesterol
are bile acids amphipathic
yes
fat absorption requries what
bile salts bc they aid in digestion by dissolving fats in the small intestine allowing absoprtion into the blood
what role does bile salt play also
cofactors and pigments
what helps with cholesterol transport
cholesterol esters that help in lipoproteins
what are cholesterol esters
- made from fatty acid esterified to cholesterol alcohol
in the liver what happens with cholesteryl ester synthesis
acytl-coa-cholesterol acyl transferase (ACAT)
Outside of the cells where does CES (chol. esther synthesis happen)
On HDLs
- lechtin cholesterol acyl transferase
TAGS are insoluble where
in plasma
cholesterol is almost what
insoluble
why do we have lipoproteins
bc Tags and cholesterol are not soluble so we need something to help with transport
how does the glycerphospholipid skin help with transport
Allows TAGs & cholesterols to be transported to various organs in the body for utilization as fuel / deposition in the storage mode (adipose tissue).
what classifies lipoprotein
density
large lipopro have what type of density
lowest
VLDL
very low D:
what are chylomicrons
-transport dietary TAGs+chol from intestines –> liver (TAGs –> muscle + adipose
wht is IDL
intermediate DL
- cholesterol management and triglyceride delivery
LDL
low density lipoprptein
-“bad” cholesterol tranports cholesterol from the LIVER
WHAT IS LDL ASSOCIATED WITH
DEPOSITION OF CHOLESTEROL ON THE ARTIERLA WALLS
WHAT IS HDL
“GOOD” cholesteron
- transports cholesterol to the liver,carries cholsteral out of the blood
atherosclerosis
means there is too much LDL
what is the flow of cholesterol
vLDL- idl- Ldl–> HDLs
what happens during heart attack
- rupture of arterial plaque
- blood clot that cause blockage of artery
- No RBS meaning no O2 supplu
- heart muscle death
- can result in phyical death
what is derived from VLDls
idls
what is the pirmary cholsterol deliverty to cell
Ldls and Idls
what carries cholesterol from cells for disposal back to liver
HDLs
what is a phospholipase
- enzyme that hydrolyzes the ester/ phosphoester bond of phospholipids
what contains phospholipases in snakes
venom
what does the phospholipase rxn produce
a lysophospholipid that acts as a detergent that dissolves RBC membranes causing them to rupture
what turns phospholipid into lysophospholipid
phospholipase A2
what are eicosansoids
derivatives of arachidonic acid
- released by cleaveage from membrane phospholipids
what is NSAID
- nonsterodial anti-inflammatory drugs: ibuprofen, naproxen, asprin
what inhibitors are NSAIDS
reversible competitive inhibotrs of PGH2 synthase COX
what is is an Irreversible Inhibitor of Prostaglandin H2 Synthase (PGH2 Synthase = cyclooxygenase = COX
asprin
what is an NSAId adverse effect
irritation of the gastric mucosa bc of the prostaglandins have protective role in GI tract
wht does COX 2 do
reduce the change of gastric irritation and decrease the risk of peptic ulceration
what is a biological membrane made of
- continuous phase, fluid lipid bilayer and discontinuous phase: proteins
what are extrinsic/perpheral membrane proteins
proteins that interact with the lipid bilayer
- bined via non covalent to membrane surface bc its easy to separate
what are intrinsic/ integral proteins
have hydrophobic region that associates with membrane; hard to remove and difficult to solubilize
how can you take integral proteins off
with a detergent
how can linked lipids be removed
from membrane by phospholipase /c
what membrane proteins bind via non covalent interactions to membrane surface and separate from membrane
peripheral
what protein has a hydrophobic region that associates with membrane hard to remove and difficult
integral
what is a mild nonionic deterngent
dissolves membranes without unfolding proteins
can be used to remove peripheral proteins
what is an ionic detergent
dissolves membranes that unfolds (denatures) proteins
removes both integral and peripheral proteins
what does a sucrose specifc porin
- act as pores which molecules can diffuse
- found in mitochondria ad in the outer membrane and gram -Ve bacteria
lipids of the billayer can move and diffuse in what sate
laterally and rotate in the plane of the membrane but they can’t do transverse
transverse diffusin is slow or fast
slow and its flip flop
photobleaching
- membrane lipid or protein is tagged with a flurorescent dye
- can be labeled with fluroescent antibodies
what is flippases
facilitate the lipids flipping from one layer to the other
what is the phospholipid composition of the membrane bilayer
asymmetrical
where are carbs located on proteins and lipids
noncytosolic side of the bilayer
Contribute to Transverse Asymmetry
glycoproteins and glycolipids
what is embedded in the membrane in a specific orientatoin curicl to their function and they also impoart assymetry to the membrane
protein
what is an example of lateral asymmetry
lipid rafts
-FA attached is satureated
what likes to self associate due to extensive van der waals interactions
spingolipid
