Left: alpha-D-glucose

Right: beta-D-glucose

Name these molecules:

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a-lactose

b(1,4) linkage between a galactose and an a-glucose

beta-lactose

beta(1,4) linkage between a galactose and a beta-glucose

Left: furan

Right: pyran

Name these types of structures:

[image]

The one of the left is D-Ribose and the one on the right is L-Ribose.

Look at the chiral carbon furthest from the carbonyl carbon.

Which is L-Ribose and which is D-Ribose?

[image]

Glyceraldehyde is the simplest aldose.

Dihydroxyacetone is the simplest ketose.

What is the simplest aldose?

The simplest ketose?

more than 4 carbons (5 or 6 most stable)

aqueous solution

Refereed to a fruit sugar

Twice as sweet as sucrose (per gram)

Used in food production

Cells can synthesize this from glucose-1-phosphate

Liver damage, cataracts, and retardation can occur when the enzyme needed to metabolize this sugar is missing

A hydroxyl group is replaced

This is often found in the complex carbohydrates attached to proteins and lipids

sucrose

alpha,beta(1,2) linkage between alpha-glucose and beta-fructose

homoglycans

heteroglycans

glycogen

most abundant in the liver and muscle cells

Carbohydrate storage from used by vertebrates

Name of organs where storage is most abundant

serine and threonine

rarely a substituted lysine group can

Are glycosaminoglycans (GAGs) linear or branched polymers?

Are they homoglycans or heteroglycans?

hyaluronic acid

chondroitin sulfate

dermatan sulfate

heparin and heparan sulfate

keratan sulfate

glycolipids

proteoglycans

glycoproteins

Proteoglycans have a higher carbohydrate content

Glycoproteins do not usually have uronic acids, sulfate groups, and disulfide repeating groups (GAGs)

The phosphorylation of glucose to glucose-6-phosphate requries 1 ATP

The phosphorylation of Fructose-6-phosphate to Fructose-1,6-biphosphate requires 1 ATP

dihydroxyacetone phosphate (a keytone)

glyceraldehyde-3-phosphate (an aldehyde)

D-Glucose + 2 ADP + 2 P_i + 2 NAD⁺ ->

2 Pyruvate + 2 ATP + 2 NADH + 2 H⁺ + 2 H₂O

F6P is converted to F1,6P

PFK-1 is the enzyme

ATP is hydrolyzed into ADP

PFK-2 has a double function, as a kinase and a phophotase, interconverting F6P and F2,6P.

Insulin activates the kinase function to produce F2,6P, which in turn activates PFK-1 for the second irreversible step in glycolysis and Pyruvate Kinase for the third irreversible step of glycolysis.

Glucagon stimulates the phophotase function of PFK-2, by converting F2,6P into F6P.  This aids in gluconeogenesis.

What enzyme breaks apart F1,6P in glycolysis? 

What are the two products?

PEP (phosphoenolpyruvate) is converted to pyruvate by pyruvate kinase.

ADP is converted to ATP.

High AMP

Insulin

F2,6P

G6P

High ATP

Glucagon

Pyruvate is used in the citric acid cycle and ETC during aerobic conditions

During anaerobic conditions pyruvate is used in lactate formation in muscle cells and ethanol formation in yeast

Glucagon

Lactate

Acetyl-CoA

High ATP

Fructose is converted by Fructokinase to DHAP in the liver and into F6P by Hexokinase in the muscle and adipose tissues.

Mannose enters glycolysis as F6P by aid of Hexokinase

Galactose enters into glycogenolysis by aid of Galactokinase

Helps in Glycogenolysis.

Can only break down a1,4 linkages but stops 4 residues from branch point

3 NADH

1 ATP/GTP

1 FADH₂

Brings oxygen and hydrogen from the matrix and makes water and releases hydrogen into the intermembrane space.

This creates a gradient of hydrogen on the intermembrane space.

4

3 to turn the synthase and 1 to bring in P_i

• Carries electrons to the ETC from glycolysis and Citric Acid Cycle
• NAD⁺ is the oxidized form
• NADH is the reduced form
• Each NADH PRODUCES 2.5 ATP during ETC

• Flavin adenine dinucleotide
• FADH₂ carries electrons to ETC from Citric Acid Cycle, entering at lower energy levels than NADH
• FAD is the oxidized form
• FADH₂ is the reduced form
• Each FADH₂ produces 1.5 ATP during ETC

superoxide O₂^-

Peroxide ROOH

Hydroxyl Radical OH

Singlet Oxygen ¹O₂

Cell signaling

Transcription Factors

Translation Factors

Immune Functions (Respiratory Burst)

Found in most animal cell membranes and contains a long-chain amino alcohol

The core of each sphingolipid is ceramide, a fatty acid amide derivative of the alcohol molecule.

Prostoglandins - Regulatory functions, as in inflammation and reproduction and digestion

Thromboxanes - platelet aggregation and vasoconstriction

Leukotrienes - increase fluid leakage from vessels and bronchoconstriction during inflammation and WBC chemotactic agent

Cased by a deficiency in the enzyme that degrades the ganglioside G_M2 (a sphingolipid), β-hexosaminidase A.  As cells accumulate this molecule, they swell and eventually die.

Tay-Sachs symptoms (blindness, muscle weakness, seizures, and mental retardation) usually appear several months after birth.

An isoprene unit can also be described as a 2-methyl-2-butene.

The difference is that a steroid is derived by a specific type of terpene, a triterpene (an aliphatic hydrocarbon with 6 isoprene units) that do not form rings.  A steroid contains four fused rings.

Chylomicrons (<0.95 g/cm³)

VLDL (0.98 g/cm³)

IDL (1 g/cm³)

LDL (1.04 g/cm³)

HDL (1.2 g/cm³)

In lipoproteins as the density increases, from that of VLDL to HDL, lipid content is removed lowering the lipid concentration and increasing the protein concentration.

Occurs in liver

Starts with DHAP of Glycerol and a tail is added on (with CoASH being released) at three points.  

NADH or NADPH is reduced in this process.

Call β-oxidation

Occurs in adipose tissue during fasting, vigorous exercise, or in response to stress.  This occurs within the matrix of the mitochondria.

Removal of a 2-carbon segment from fatty acid to release acetyl-CoA.

Primarily occurs in the liver (but also occurs in the cytoplasm of most cells)

Occurs when the diet is low in fat and/or high in carbohydrate or protein

The enzyme used is a homodimer

Almost all arachidonic acid is stored in membranes and released in response to appropriate signals (typically steroids, this is the rate limiting step)

Once released from the membrane, cell-specific enzymes then convert arachidonic acid into the specific eiconsanoid needed by the cell.

Allosteric modulators

Covalent modification

Hormones

Fatty acid synthesis occurs predominately in the cytoplasm, whereas beta-oxidation occurs within mitochondria and peroxisomes.

The enzymes that catalyze fatty acid synthesis are significantly different in structure that those in beta-oxidation.  In eukaryotes this is called fatty acid synthase.

The intermediates of fatty acid synthesis and  beta-oxidation are linked through thioester linkages to ACP and CoASH, respectively.

Beta-oxidation produces NADH and FADH₂.  Fatty acid synthesis consumes NADH.

This is a key enzyme that allows for fatty acid synthesis.

ACC1 is inactivated as a result of high AMP levels, glucagon, and/or palmitoyl-CoA accumulation.

ACC1 is activated by high insulin levels (glucose readily available) and deactivated by high glucagon levels and/or the presence of epinephrine.

Glucagon

epinephrine

cortisol

Bacteria are responsible for nitrogen fixation into NH₃

Plants and microorganisms assimilation incorporate NH₃ into organic molecules

Describe the importance of nitrogen metabolism to organic life

Isoleucine

Leucine

Lysine

Methionine

Phenylalanine

Threonine

Tryptophan

Valine

Name the Essential Amino Acids (EAA)

Alanine

Arginine

Asparagine

Aspartate

Cysteine

Glutamate

Glutamine

Glycine

Histidine

Proline

Serine

Tyrosine (can be synthesized IFF Phenylalanine is present)

Name the Nonessential Amino Acids (NAA)

Glutamate family

Serine family

Histidine family

What are the NAA Biosynthetic Families

Aspartate family

Pyruvate family

Aromatic family

Biosynthetic Families with some NAA and some EAA

Aminotransferases perform transamination by reversibly moving an amino group from an a-amino acid to an a-keto acid

Describe Transamination

a-ketoglutarate/glutamate – important for AA metabolism

Oxaloacetate/aspartate – important in the removal of nitrogen via the urea cycle

Pyruvate/alanine – important for the alanine cycle

Major Transamination Pairs

PLP is derived from vitamin B₆

Sources for precursors would be green leafy vegetables and meat (fish, poultry, red meat)

Describe the Transamination Reaction that Refer to Vitamin B₆

Folate (Vitamin B₉)

THF (active form of folate)

Cobalamin (Vitamin B_12­)

S-adenosylmethionine (SAM)

Important Biomolecules are involved in One-Carbon Metabolism

GABA

Neurotransmitter that is formed from glutamate by Glutamate decarboxylate

Inhibitory neurotransmitter in CNS that results in the influx of Cl^- and release of K⁺

Effect of GABA

Xanax

Valium

Ativan

Klonopin

Drugs that are used to alleviate anxiety and aggressive behavior by enhancing GABA’s action

Catecholamines

Neurotransmitter class that is derived from Tyrosine

Dopamine and Norepinephrine

Catecholamines that are excitatory neurotransmitters

Parkinson’s (L-DOPA can alleviate some symptoms)

Which disease state has been associated with deficient dopamine production (and what can alleviate some symptoms)

CNS neurotransmitter associated with several eating disorders, mood temperature regulation, pain perception and sleep.

Describe Serotonin

Tryptophan

Which AA is Serotonin produced from

Metabolic flexibility because of rapid changes in protein concetration

Protects cells from accumulation of abnormal proteins

Some cellular processes depend upon timely degradation of specific proteins

N-terminal residues – basic or hydrophobic residues are less stable, whereas sulfur or hydroxyl-containing residues increase stability

Protein motifs – specific protein sequences can cause a protein to be rapidly degraded

Oxidized residues – some AAs are altered by oxidases, thus promoting degradation

What are three ways that protein stability can be predicted?

The addition of ubiquitin will target a protein for destruction by a proteasome

1. E1 is attached and activates the process
2. E2 replaces E1 and conjugates the protein to E3
3. E3 is ligated to the protein and is specific to protein or protein class

Amino acids degrade into four molecules found in the citric acid cycle

Acetyl-CoA

a-ketoglutarate

Succinyl-CoA

Oxaloacetate

Purine bases are degraded to uric acid

Postprandial refers to a well-fed state, in which you are gaining all your nutrients from diet as normal.

Postabsorptive state refers to a fasting state, in which your body undergoes breakdown of certain tissues in order to gain necessary biomolecules for life.

Insulin drives glucose out of the bloodstream by activating anabolic processes, such as lipogenesis and glycogenesis.

Glucagon increases glucose by activating catabolic processes, such as lipolysis and glycogenolysis.

Type I - insulin production deficiency

Type II - decreased sensitivity to insulin and sometimes decreased insulin production

Hyperglycemia

Glucosuria

Osmotic diuresis

Occurs in cases of starvation and in Type I diabetes. 

Ketogenesis leads to ketosis, an elevation of ketone bodies.  Diabetic ketoacidosis is an uncontrolled form of ketogenesis that is life-threatening.

Norepinephrine signaling leads to thermogenesis in adipose tissue.

Thermogenin decomples the ETC, allowing the energy from the proton motive force to be released as heat. 

This process is powered by the "burning" of fats.