Block 4 Nishimoto Questions Flashcards
Zellweger Syndrome
Lack of functional peroxisomes; Can’t Oxidize VLCFA’s
Which steps of Mitochondrial Long-Chain FA Metabolism Occurs in Cytosol?
Fatty acyl CoA Synthetase Activates FA to FattyAcylCoA
Which KB packs “extra punch”
Beta-hydroxybutyrate (NADH)
Where is Fatty Acyl CoA Oxidized in Liver?
Mitochondrial Matrix
Where does Succinyl CoA get its CoA for Ketone Oxidation
CAC Cycle or Oxidation of Odd-Chain or Branched-Chain FA’s
Where does Omega-oxidation occur?
ER, forms Dicarboxylic Acids
Where does maturation of Chylomicrons occur?
Blood, pick up ApoE and ApoCII from HDL
Where does final oxidation of Fatty Acyl CoA occur?
Mitochondrial Matrix
Where are OH Groups of Cholesterol in a Lipoprotein
Surface
When is MC AcylCoA Dehydrogenase deficiency noticed?
When glucose levels are low and FA’s cannot be completely oxidized
When is Gluconeogenesis main source of blood glucose
After ~16 hours
When does muscle use blood glucose
High insulin (fed state) or during exercise
When does muscle primarly use Glycogen?
Severe exersize
When does brain start using KB’s?
Roughly day 3 (Starved State); KB levels in blood aren’t high enough until this day.
When do you need extra ATP in Palmitate synthesis?
When starting with just Acetyl CoA (no Malonyl CoA)
When are Malonyl CoA levels elevated?
Fed State; It’s the substrate for FA Synthesis produced by Acetyl CoA Carboxylase
What size FA’s use Carnitine Cycle for Membrane Transport
Long Chain (12-20)
What size FA’s are catabolized in peroxisome?
Very Long Chain (>20)
What provides the omega-methyl group of palmitate in FA synthesis?
Acetyl CoA
What provides the 2 carbon units that are added to the growing Fatty Acyl chain?
Malonyl CoA
What products of lipid digestion do Intestinal epithelial cells absorb?
FA’s and 2-MG’s
What percent of Bile Salts are excreted?
5
What part of intestinal cell produces TG?
sER
What part of intestinal cell produces apoB-48
rER
What part of FA Synthase reacts with Malonyl CoA
Sulfhydryl group of Phosphopantetheinyl residue
What is required to transfer lipid to apoB-48?
MTP
What is required for FA chain to start?
An AcCoA is required to be acceptor of Malonyl Transfer; Must make MalonylCoA from AcCoA
What is produced converting Beta-Hydroxybutyrate to Acetoacetate
NADH + H+
What is necessary to convert Acetoacetate to Beta-hydroxybutyrate
NADH + H+
What is Acetyl CoA from Long-Chain FA Metabolism used for in Liver
KB Synthesis (TCA Cycle in other tissues)
What is a key factor in control of Ketone Synthesis
Availability of FA’s
What happens to remnants of Chylomicron breakdown?
Taken up by liver by receptor-mediated endocytosis; Digested by Lysosomes; Products released into Cytosol
What happens to HMG CoA in Ketone Synthesis
Converted to Acetoacetate, producing one AcetylCoA
What happens to FADH2’s produced in VLCFA oxidation?
Transfer electrons to O2; Produce H2O2
What happens to FA’s once absorbed into intestinal epithelium?
Esterfied to the 2-MG’s to form TG
What happens to Citrate once pumped into Cytosol?
Makes OAA and AcCoA
What happens to Bile Salts no longer needed?
Absorbed in Ileum, Returned to Liver via Entero-hepatic Circulation
What happens to Acetoacyl CoA in Ketone Oxidation?
Cleaved to 2 Acetyl CoA by Thiolase
What happens to 2-MG’s once absorbed into intestinal epithelium?
Esterfied to FA’s to form TG’s
What FA’s under Alpha-Oxidation?
Branched-Chain FA’s
What enzyme activates Fatty Acids
Fatty Acyl CoA Synthetase
What electron carriers are produced during Beta-oxidation?
NADH, FADH2
What donates a CoA to Acetoacetate in Ketone Oxidation?
Succinyl CoA
What does the Final Step in Oxidation of Odd Chain FA’s produce
Propionyl CoA (3 Carbons)
What does the conversion of Proprionyl CoA to Succinyl CoA require?
ATP, Biotin, Vitamin B12
What does Pancreatic Lipase require to work?
Protein Colipase to stabilize and localize lipase near bile salt-TG particle
What does Pancreatic Lipase Colipase need to work?
Bile salts to emulsify TG’s
What does omega-oxidation of FA’s produce?
Dicarboxylic Acids -> May be excreted or conjugated to Glycine or Carnitine
What does muscle use during resting state or mild exersize?
KBs or FA’s (FA’s preferred)
What does Desaturase require
Molecular Oxygen
What does Beta-oxidation of Fatty Acyl CoA generate in mitochondria
NADH, FAD(2H), Acetyl CoA
What do Peroxisomes not produce from Beta-Oxidation?
FAD(2H)
What bond is cleaved in Beta-oxidation?
alpha-beta bond
What activates LPL on capillary walls in adipose and muscle tissue?
ApoCII
Uses for FA’s from Adipose during Basal Fasted State
Liver for ATP and KB’s (which go to muscle, not brain yet); Muscle for AcCoA/TCA
Types of FA’s oxidized in Peroxisomes
VLCFA, Some LCFA’s; Branched-Chain >8
Two products of Glycerol Metabolism in Liver
DHP, Glyceraldehyde-3-P
Two Main Ketone Fuels
Beta-hydroxybutyrate, Acetoacetate
To what part of FA Synthase is Phosphopantheine linked?
Serine residue of Acyl Carrier Protein segment
To what is Alanine from muscle converted?
Pyruvate
T/F: the Liver can use KB’s as fuel if is has to
False, doesn’t have correct enzymes
T/F: One isozyme of Acyl CoA Dehydrogenase can oxidize all FA lengths?
False, several different isozymes
Surface of Lipoproteins
Phospholipids and Proteins on surface, with hydrophilic regions interacting w/ water
Subcellular location of FA Activation
Cytosol (or Mitochondria???) (Fatty Acyl CoA Synthetase)
Subcellular Location of Elongase
Endoplasmic Reticulum
Subcellular Location of Desaturase
ER
Subcellular Location of CPT2
Inner Mitochondrial Membrane
Subcellular Location of CPT1
Outer Mitochondrial Membrane
Steps Unique to VLCFA Oxidation
Oxidized in peroxisomes by beta-oxidation to produce medium/short-chain; Converted to Carnitine dervatives and sent to mitochondria
Source of Pyruvate in FA Synthesis
Glycolysis (Glucose)
Source of Glycerol for Lipogenesis in Fed State?
Glycolysis
Source of Citrate in FA Synthesis
Mitchondria: OAA and AcCoA from Pyruvate; AcCoA + OAA = Citrate
Site of Catabolism and Membrane Transport of Very Long Chain FA’s
Peroxisome; Unknown
Site of Catabolism and Membrane Transport of Short Chain (2-4) FA’s
Mitochondrion; Free Diffusion
Site of Catabolism and Membrane Transport of Medium Chain (4-12) FA’a
Mitochondrion; Diffusion
Site of Catabolism and Membrane Transport of Long Chain (12-20) FA’s
Mitochondrion; Carnitine Cycle
Role of Fatty Acyl Carnitine
Carnatine carries FA into mitochondria (Enzymes required)
Role of CPT1 in Ketone Synthesis Regulation
Converts FA’s to FA-Carnitine (which then is converted to FA-CoA)
Role of Citrate in FA Synthesis
Provides AcCoA and NADPH for FA Synthesis
Regulation of VLCFA Oxidation
Just VLCFA availability
Regulation of Alpha-Oxidation of Branched-Chain FA’s
None
Regulated step of FA Synthesis
Acetyl CoA converted to Malonyl CoA by AcCoA Carboxylase (Needs CO2, ATP, Biotin)
Reducing agent used by Desaturase
NADH
Reducing agent in FA Synthesis vs Beta-Oxidation
NADPH vs NADH, FADH2
Recycling of OAA back to mitochondria makes what?
NADPH
Pyruvate Carboxylase
Pyruvate to OAA
Purpose of Thiolysis in Beta-Oxidation
Cleavage step, produces 1 AcetylCoA and FACoA that is 2 carbons shorter
Purpose of Protein Colipase
Binds to lipase and emulsified fat increasing lipase action
Products of initial beta-oxidation of VLCFA in peroxisomes?
AcetylCoA (Acetyl-Carnitine); SCFA CoA/MCFA CoA (SCFA-carnitine/MCFA-Carnitine)
Products of Beta-Oxidation of Even-Chain FA
Acetyl CoA; FADH2, NADH
Production of Dicarboxylic Acids
Omega-Oxidation of FA’s; May be excreted or conjugated to Glycine or Carnitine
Processing of Propionyl CoA produced from Odd Chain FA Oxidation
Add carbon and form Succinyl CoA
Primary Tissues for FA Synthesis vs Beta-Oxidation
Liver, Fat vs Liver, Muscle
Prevention of newly synthesized FA’s from oxidation
Malonyl CoA (high during FA synthesis) inhibits CPT1, which tranports LCFAs into mitochondria
Preferred substrate of muscle during prolonged exercise
Glucose
Preferred substrate of Cardiac Muscle 2 hours after meal
FA
Positive Regulators of Ketogenesis
(1) High FA’s; (2) High CPTI; (3) Low Malonyl CoA; (4) High ATP; (5) High NADH; (6) Low OAA
Positive regulation of FA Synthesis
Citrate, Insulin
Positive regulation of Acetyl CoA Carboxylase
Citrate, Insulin
Net AcetylCoA’s used to make 1 Acetoacetate
1 (2 initially, but one produced)
Negative Regulators of Ketogenesis
(1) Low FA’s; (2) Low CPTI; (3) High Malonyl CoA; (4) Low ATP; (5) Low NADH; (6) High OAA
Negative regulation of Acetyl CoA Carboxylase
Palmitoyl CoA, Low ATP (High AMP)
Negative regulation of Acetyl CoA Carboxylase
Palmitoyl CoA, Low ATP (High AMP)
Metabolic Changes when reach Starved State
Brain uses KB’s, Muscle doesn’t; Mucles stops breaking down Protein (less Urea in Urine)
Maturation of Chylomicrons
Occurs in blood; Pick up ApoE and ApoCII from HDL
Malonyl CoA
Inhibits CPT1; When FA’s being synthesized, blocks FA oxidation; Intermediate in FA Synthesis
Malic Enzyme
Malate to Pyruvate; Producing CO2 and NADPH
Malate Dehydrogenase
OAA to Malate, using NADH
Major target of Glucagon and effect on cAMP
Liver, Increases cAMP; (Activates Lipase in Adipose?)
Major Component of a Chylomicron
TG
Major apolipoprotein in Chylormicrons
apoB-48
Location of HMG CoA Synthase
Liver Mitochondria
Lipolytic Hormones
Glucagon (fasting, starvation); Epi/NE (stress); ACTH
KB levels during prolonged fasting
Rise substantially thru day 20-30
Intracellular Lipolysis Cascade after Glucagon binds
Adenylate Cyclase -> cAMP -> PK -> TAG Lipase -> TAG to DAG to FFA’s -> FFAs released
Insulin stimulates the secretion of what from Adipose cells?
LPL (Lipoprotein Lipase)
Initial Oxidation of Branched-Chain FA’s
Alpha-oxidation in Peroxisomes to produce CO2, Propionyl and Acetyl CoA; MCFA’s sent to mitochondria as carnitine derivatives
Inhibitor of CPT1
Malonyl CoA
In what part of intestinal cell does assembly of lipoproteins occur?
ER and Golgi
In what organ does the synthesis of FA from Glucose mainly occur?
Liver
In what form are TG’s ultimately absorbed in small intestine?
FA’s and 2-MG’s
In what form are Hepatic TAG’s exported from Liver
VLDL’s
In Palmitate Synth., what extra do you need if starting from just AcetylCoA
7 ATP to add CO2
How many FADH/NADH molecules are produced for each cycle of Beta-oxidation?
1 (=4 ATP)
How many carbons added with each repeat of FA Synthesis
2 Carbons
How many ATPs per NADH in FA Oxidation?
2.5
How many ATPs per FADH2 in FA Oxidation?
1.5
How many ATPS from 1 Palmitate via Beta-Oxidation?
7 Cycles; 7 NADH and 7 FADH2 = 28 ATP; 8 AcCoA = 80; Minus 2 ATP for activation; Total=106 ATP
How many ATP are required to Activate Beta-oxidation
2
How many Acetyl CoA’s does Palmitoyl CoA produce?
8, 7 repetitions of the Beta-oxidation spiral
How many Acetyl CoA’s are needed to make 1 HMG CoA
2
How is Acetoacetate activated in Ketone Oxidation?
Accepts a CoA group from Succinyl CoA
How does Muscle get energy during basal fasted state?
KB’s from liver (which come from FA’s from adipose); FA’s directly from Adipose
How does low calorie diet affect Acetyl CoA Carboxylase
Decreases rate of transcription -> Inhibit FA Synthesis
How does Liver get ATP during Basal Fasted State?
FA’s from Adipose
How does Insulin Ratio induce TG degradation in Adipose?
(1) High Glucagon/Insulin elevates cAMP; (2) PKA Activated; (3) Hormone-Sensitive Lipase Phosphorylated; (4) TG broken down into FA and Glycerol
How does increased insulin stop TG degradation in Adipose tissue?
Stimulates the phosphatase that inactivates HSL in fed state
How does high calorie diet affect Acetyl CoA Carboxylase
Increases rate of transcription -> Promotes FA Synthesis
How does Brain get ATP during Basal Fasted State?
Glucose from Gluconeogenesis/Glycogenolysis
How do high FA levels affect CPTI
Malonyl CoA inhibition of CPTI is lifted by inactivation of AcCoA Carboxylase
How do Glucose levels change during Fasting
Drop Initially, then remain relatively constant indefinitely
How do FFA levels change during fasting
Rise initially, then remain relatively constant indefinitely
How do fat cells make Glycerol-3-Phosphate
From Glucose by Glycolysis; They lake Glycerol Kinase
How do activated Acetyl groups exit mitochondria in FA Synthesis?
As Citrate
How do activate Acyl groups enter mito in Beta-Oxidation
As Carnitine Derivative
How are the Acetyl CoA’s produced in (terminal step of) Ketone Oxidation
Acetoacetyl CoA is cleaved by Thiolase
How are dietary FA’s transported in blood?
Chylomicrons
How are Beta-Oxidation and CAC similar?
Hydration, production of FADH2 and NADH
Goal of FA Synthesis
Store excess glucose as FA’s
From what is Acetone spontaneously formed?
Acetoacetate, giving off CO2
From what does Chylomicron get ApoE and ApoCII
HDL
From what are Bile Salts derived?
Cholesterol (maintain their ring structure)
For what does the liver recycle Glycerol?
Gluconeogenesis and TG Synthesis
First Three Steps of Ketone Synthesis (Just substrates)
(1) 2 AcetylCoA –> (2) Acetoacetyl CoA –> (3) HMG CoA
First Step of Ketone Oxidation when starting with Beta-Hydroxybutyrate?
Oxidation to Acetoacetate
First Committed Step of FA Synthesis
Acetyl CoA converted to Malonyl CoA by AcCoA Carboxylase (Needs CO2, ATP, Biotin)
Fate of Proteins in Muscle during Basal Fasted State
Broken down into AA’s, which are used for Gluconeogenesis
Fate of FAD(2H) and NADH produced in beta-oxidation of FA’s
Re-oxidized by ETC, producing ATP
Extra requirements of Beta-Oxidation of Unsaturated FA’s
2 Extra Enzymes (Isomerase and Reductase) to modify double bonds
Epinephrine
Stimulates Glycogenolysis in Skeletal Muscle/Liver; Stimulates Lipolysis
Energy resevoir of Cardiac Muscle
Glycogen (few reserves)
End Products of Lipolysis
Acetyl CoA, Glycerol
Effect of Palmitoyl CoA on Acetyl CoA Carboxylase
Decreases rate of transcription -> Slows FA Synthesis
Effect of Malonyl CoA on CPT1
Malonyl CoA inhibits CPTI, decreasing KB synthesis
Effect of Low OAA levels of Ketogenesis
Diverts AcCoA into Ketogenesis from TCA; Rate of Citrate Synthase reaction reduced
Effect of Low ATP/High AMP on Acetyl CoA Carboxylase
Activates PK that phosphorylates (deactivates) -> Inhibit FA Synthesis
Effect of Insulin on Beta-Oxidation
Increase Malonyl CoA, Decrease Beta-Oxidation
Effect of Insulin on Acetyl CoA Carboxylase
Stimulates dephosphorylation (activation) -> Promotes FA Synthesis
Effect of High NADH/FADH2 on Beta-Oxidation
Inhibits
Effect of High NADH on Ketogenesis
High NADH depletes OAA to help shunt AcCoA to make KB’s b/c less OAA is available for Citrate
Effect of High NADH levels on Ketogensis
Converts OAA into Malate, which causes shunting of AcCoA into Ketogenesis instead of TCA Cycle
Effect of High ATP on Ketogenesis
(1) High ATP = Less NADH Oxidized; (2) NADH/NAD+ ratio increases; (3) OAA converted to Malate; (4) AcCoA diverted from TCA to Ketogenesis, b/c of low OAA levels
Effect of Glucagon on F-2,6-BisP
Decreases, Slows Glycolysis
Effect of Citrate on Acetyl CoA Carboxylase
Increases rate of transcription -> Promotes FA Synthesis
Effect of AMP-PK (muscle,liver) on Beta-Oxidation
Decrease Malonyl CoA, Increase conversion of Fatty Acyl CoA to Fatty Acyl Carnitine
During what state is Urea production highest
Fasting, then protein breakdown slows
Difference b/t Bile Salts and Cholesterol precursor
Rings in Bile Salts contain more Hydroxyl Groups, a polar side chain, Lack a 5-6 double bond
Diff b/t FA elongation vs synthesis?
Elongation occurs while FA is bound to CoA, rather than to ACP
Cortisol
Gluconeogenesis, AA Mobilization, Lipolysis
Components of MTP
PDI, a chaperone; and TG Transfer portion
Citrate Synthase
OAA to Citrate, Using Acetyl CoA
Citrate Shuttle
Citrate out of Mito, Pyruvate in (Shuttling Acetyl CoA out for FA Synthesis)
Citrate Lyase
Citrate to OAA using ATP, Producing Acetyl CoA for FA Synthesis
Cholesterol Esters in Lipoproteins
OH group esterfied to a FA; Found in interior of Lipoprotein
Carrier of FA Synthesis vs Beta-Oxidation
Protein (ACP) vs Coenzyme A
Carnitine Deficiency
Inability to transport LONGCHAIN FA’s into mitochondria
Carnitine Cycle
Exchange of Carnitine and Acyl Carnitine; Long Chain FA’s into mitochondria
Cardiac Fuels
Primarily FA’s; Will use KB’s over Glucose
cAMP and Lipolysis
Increased cAMP activates Lipase, increasing Lipolysis in Adipose tissue
Apo B in Liver vs Intestine
Same gene; RNA Editing; Instestinal version (B-48) is half the size
Antilipolytic Hormones
Insulin
Acyl CoA “Desaturases”
ER; Contain FAD, Cytochrome B5, and an Iron-Sulfure Center; Various specificities, <10
Activities affected by MTP loss
Chylomicron and VLDL assembly, both need an apoB protein to assemble
Actions of MTP
Required to transfer lipid to apoB-48, and to transfer lipid from cytoplasm to ER lumen; Helps recruit TG lipid droplets as particle grows
Actions of Lipolytic Hormones
Increase adipose cAMP and activate Lipase
Action of Pancreatic Lipase
Cleaves FA’s from positions 1 and 3 of TG, producing 2 FA’s and a 2-MG
Action of LPL
Breaks down TG’s to FA’s; FA’s taken into Adipose Cells
Action of Gastric and Linguinal Lipases
Hydrolyze short/medium chain FA’s from TG’s
Action of Carnitine in Mitochondrial Long-Chain FA Metabolism
Transports activated Fatty Acyl CoA into mitochondria
Action of Beta-Hydroxybutyrate
Interconverts Acetoacetate and Beta-hydroxybutyrate
Action of ApoE
Binds to receptors (in liver) that uptake chylomicron remnants
Abetalipoproteinemia
Loss of TG Transfer Activity (MTP); Inability to take in and distribute dietary fats
5 Steps of FA Synthesis
(1) Transfer of Malonyl; (2) Condensation of malonyl; (3) Reduction of beta-ketoacyl group; (4) Dehydration forms double bond; (5) Reduction of double bond w/ NADHP
2-Carbon Donor of Elongation and Reducing Agent
Malonyl CoA, NADPH
2 Steps of FA Activation
(1) ATP added to form high-energy Fatty Acyl AMP; (2) AMP is exchanged for CoA (product is Fatty Acyl CoA
2 Sources of NADPH for FA Synthesis
Pentose Phosphate Pathway, Malic Enzyme (Malate to Pyruvate)
2 Components needed for TG Synthesis in Adipose
Glycerol-3-Phosphate from Glucose and FA’s from VLDL’s
1 Main difference b/t Ether Lipid and other Glycerolipids
Ether instead of Ester bond at C1
2 Mechanisms to Add Head Group to Phosphatidic Acid
(1) Activate Head group with CTP; (2) Activate DG w/ CTP
2 Starting components of Ceramide Synthesis
Palmitoyl CoA and Serine
2 Types of Ether Glycerolipids
Plasmologens and PAF
3 Components to make Phosphatidic Acid
Glycerol-3-P, 2 FA-CoA
3 Steps of TG Synthesis
(1) Glycerol-3-P from Glycerol or Glucose; (2) Glyc-3-P -> Phosphatidic Acid; (3) PT Acid -> DG -> TG
4 Types of Glycolipids
Cerebrosides, Sulfatides, Globosides, Gangliosides
ABO blood groups are determined by what type of lipids
Sphingolipids
Action of Pancreatic Lipase and Colipase
Hydrolyzes TG and DG, forming 2-MG and 2 FA’s
Alpha-Galactosidase deficiency
Fabry Disease
Backbone of Sphingolipids and Glycolipids
Ceramide, not Glycerol
Beta-glucocerebrosidase deficiency
Gaucher Disease
Ceramide
Sphingosine linked to FA at 2 w/ amide
Ceramide backbone with carbohydrate group attached
Glycolipids
Common Intermediate of Membrame Phospholipid Synthesis
Phosphatidic Acid
Components of Cardiolipin
Phosphotidylglycerol and CDP-DAG
Components of Glycerophospholipids
Glyercol, 2 FA, “Head Group”
Degradation of Sphingolipids
Occurs in Lysosomes
Difference b/t Plasmalogen and PAF
At C1: Unsaturated vs Saturated; At C2: Acyl vs Acetyl; At C3: Head group Ethanolamine vs Choline
Diglyceride Acyltransferase is part of what complex?
TG Synthetase
Ether Glycerolipid vs Glycerophospholipid
Ether bond at C1 instead of ester bond to FA
Fabry Disease
Alpha-Galactosidase Deficiency; Accumulation of Globosides
From what is Arachidonic Acid derived?
Phospholipids
From what other phospholipid can you make phosphotidylserine
phosphotidylethanolamine (reversive exchange)
Functions of Glycolipids
Cell recognition, Protective effects, Binding site for some toxins
Ganglioside
Ceramide - Sugars - NANA
Gaucher Disease
Beta-glucocerebrosidase deficiency; Ceramide-glucose not broken down; Accumulate Glucocerebroside
General purpose of Sphingolipids
Help cell-cell, cell-matrix interactions
Globosides
Ceramides attached to 2 or more sugars
Glycerolneogenesis during Fasting
Adipose tissue can use Lactate, Pyruvate, & AA to regulate FA release; Gluc-3-P -> DHAP -> Glyercol-3-P
Glycolipid Structure
Ceramide backbone with Carbohydrate group attached
Head group of Phosphatidic Acid
H
Head group of Phosphatidylcholine
Choline
How is Glycerol-3-P produced in Adipose tissue normally?
Glucose -> DHAP -> Glycerol-3-P (using NADH)
How is Glycerol-3-P produced in Liver?
Glycerol Kinase phosphorylates; Glucose to DHAP to Glycerol-3-P (Using NADH)
How many high energy Phosphates are necessary to activate a FA?
2, ATP -> AMP
How many hydrocarbon tails does PC have?
2
Inability to degrade Glycolipids and Sphingomyelin in membranes
Mucolipidosis
Neutral Glycolipids
Contain one or more sugars
Phenotype w/ Glycerolneogenesis Pathway KO
Release abnormally high FA in blood in fasting and have low fat stores
Phosphotidylethanolamine to Phosphotidylcholine
Add three Methyl Groups (3 SAM’s)
Plasmologen locations
Mitochondria, Myelin, Muscle
Polar head group of Ceramides
Don’t have one
Polar head group of Glycolipids
Carboydrate
Product when Dephosphorylate Phosphatidic Acid
DAG
Requirements for Ceramide synthesis
Serine, PalmitoylCoA, FACoA, NADHP, FAD
Structure of Ether Lipid (Plasmolgen)
Ether bond at 1 to Long Chain Alcohol (Double bond b/t carbons 1 and 2); FA at 2; Polar Head Group at 3
Subcellular Location of TG Synthetase Complex
ER
Sulfatide
Ceramide attached to sulfated galactose
Synthesis of Sphingomyelin from Ceramide requires what?
Addition of Choline from Phosphatidylcholine
T/F: Distribution of complex lipids is PM is symmetric
FALSE
T/F: Glycolipids contain a phosphate
FALSE
Tay-Sachs Disease
Hexosaminidase A Deficiency; GM2 Ganglioside Accumulates
Tissue with Glycerol Kinase
Liver
Type of Complex Lipid with Carbohydrate
Glycolipid
Type of Plasmalogen in Heart Muscle
Choline Plasmologen
Type of Plasmalogen in Myelin
Ethanolamine
What 2 components make Sphingosine
Palmitoyl CoA and Serine
What activates sugars in Glycolipid Synthesis
UDP or CMP
What causes Mucolipidosis
Inability to degrade Glycolipids and Sphingomyelin in membranes
What cells secrete LPL and in response to what?
Adipose, Insulin
What determines type of Glycolipid
Nature of carbohydrate
What do Sphingophospholipids and Glycolipids share?
Sphingosine backbone the 2-FA links by an Amide
What does Inisitol react with to form PI?
CDP-DG
What does synthesis of Glycerolipids require
NADPH, AcylCoA, DHAP, and activated Ethanolamine
What drives the reaction of Phosphatidic Acid to Glycerophospholipids
CTP
What helps sulfate Glycolipids
PAPS
What is the 2-fatty acid replaced by in PAF
Acetyl Group
What links FA’s in Sphingolipids/Glycolipids
Amide, not ester or ether
What membrane is enriched with Cardiolipin?
Inner Mito Membrane
Where are Glycolipids predominate
Neural Cells
Where does synthesis of Glycolipids occur?
ER and Golgi (sugars sequentially added as activated glycosyl residues)
Where is PAF made?
Peroxisomes
Where is sphingomyelin enriched?
CNS along w/ Glycolipids
Which Complex Lipids do not have Polar Head Groups
Glycolipids and TAG’s
