Lecture 2 Biochem

1. Amino acids: make proteins 2. Fatty acids: make phospholipids 3. Nucleobases: Make DNA/RNA 4. Carbohydrates: Make phospholipids, saccharides, DNA/RNA

1. hydrocarbon chains (hydrogen and carbon)
2. Functional groups (responsible for the characteristics of a compound)

1. Amino group
2. Carboxyl group
3. Variant group (responsible for the characteristic polar/nonpolar, positive and negative features)

Peptide bonds

1. 2 fatty acids
2. glycerol
3. phosphate

Ester bond

Cellular membranes (bilayers) and micelles

-Naturally occuring organic compounds that mainly are composed of carbons
-General formula is CxHxOx
-They are important because they are one of the main sources of energy

Extra sugar that is stored in the liver and muscles

Glycosidic bond

One sugar, few sugars, many sugars

Simple sugars have 1 to 2 saccharides: glucose, fructose, lactose, and sucrose
Complex sugars have poly saccharides: starches, fibers, and glycogen

1. Amino acids: make proteins 2. Fatty acids: make phospholipids 3. Nucleobases: Make DNA/RNA 4. Carbohydrates: Make phospholipids, saccharides, DNA/RNA

-Sucrose (a non-reducing table sugar)
-alpha-D-glucose (1,2) -alpha-fructuose

-Lactose (milk sugar)
-Beta-D-Galactose (1,4) -Glucose

-Maltose (beer sugar)
-Alpha-D-glucose (1,4) -glucose
-Formed by splitting starch

Sugars where the anomeric carbon has an OH group attached that can reduce other compounds (must have a free anomeric carbon)

Aldoses have aldehyde. Uses -ose.
Ketoses have ketone. Uses -ulose.

Simplest aldose is glyceraldehyde, simplest ketose is dihydroxyacetone

3-6 carbons

1. glyceraldehyde (3 C)
2. Erythrose (4 C, intermediate for metabolism)
3. Pentoses (5 C)
4. Hexoses (6 C)
5. Sedoheptulose (7 C intermediate for metabolism)

Refers to second to last carbon from the bottom of the Fisher projection.
If -OH is to the left, it is L
If -OH is to the right, it is D

Non-superimposible mirror image. Important example is D and L enantiomers.

Different combinations of the same number of carbons, hydrogens, and oxygen. 3/4 of the most important hexoses are isomers.

Phosphorylation

Only one chrial center with a different arrangement

A carbon attached to 4 different groups

1. Affect rotation of plane polarized light
2. Interact with other chiral centers than each other

1%, most are in their closed ring form

Hemiacetylation, hemiketylation

Beta (anomeric -OH facing up)

The anomeric carbon being attacked from either the front or back

AKA "ring-chain tautomerism". Has the same formula, but exist in different forms

Furanose (5 membered ring), Pyranose (6 membered ring)

Chair conformation

Anomeric carbon of aldose is C1, ketose C2.

It is an important structure of nucleotides because it can be converted to deoxyribose (has no oxygen on C2). It is always found in beta confirmation.

Phosphorylation

Formation of galactosamine

N-acetylglucosamine

Derived from glucose by oxidizing the C6 from an alcohol to a carboxyl group, gives negative charge at physiological pH

Makes sucralose sweetener

By condensation/dehydration (removal of a water)

Disaccharides and polysaccharides allow for easier transport

-It is broken down into galactose and glucose through a hydrolysis reaction (water is needed to break the bond)
-The beta glycosidic bond of lactose is the only beta glycosidic bond naturally split by lactase

Individual is no longer able to split the b-glycosidic bond between galactose and glucose

1. diarrhea (due to lactose in intestinal lumen through osmotic absorption)
2. Bloating and abdominal plain (because gas producing bacteria use it for food and thrive in large intestine)
3. Flatulence (because of thriving gas producing bateria in the large intestine)

1. Mucopolysaccharides
2. Proteoglycans
3. Glycoproteins

-Long unbranched and repeating disaccharide monomers with modified sugars
-Present in extracellular matrix and support water binding capacity
-Form biofilms
-Form hyaluronic acid which is important compoenent of synovial fluid

1. Amino sugar (N-acetylgalactosamine or N-acetylglucosamine)
2. Uronic acid (glucuronate or iduronate)

They have a strong negative charge because of the sulfate and -OH groups

GAGs can covalently bind to proteins to form proteoglycans

They serve as excellent lubricants and shock absorbers due to water retention, great volume, and strength

Hurler syndrome, Hunter syndrome, and Morquio syndrome

1. Hyaluronic acid 2. Dermatan sulfate 3. Chondroitin 4. Heparan sulfate 5. Keratan sulfate

1. They organize the saccharide chains and prevent them from scattering in the extracellular matrix
2. The regulate the movement of molecules throughout the extracellular matrix
3. They impact signaling molecules

-They are saccharides bound to proteins
-Form through glycosylation by attaching oligosaccharides to protein (done during post translational modification in Golgi apparatus)

1. Almost all blood cells are glycosylated
2. Immune defense in form of IGG
3. Surface/excreted glycoproteins carry sugars

N linked to Asn or O linked to Ser or Thr

-Autosomal recessive disorder that causes the lack of enzyme alpha-L-iduronidase that is needed to digest sugar and break down GAGs dermatan and heparan sulfate
-Also called lysosomal storage diseases: mucopolysaccharidoses type 1 or gargoylism

-Undigested sugars build up, causing damage to brain, heart, and other organs
-Build up of heparan sulfate and dermatan sulfate occurs
-Build up of mucopolysaccharide leads to coarse face features
-Corneal clouding *defining feature *

-Less severe than Hurler's syndrome
-Also called mucopolysaccharidoses type II
-It is X-linked and is a chronic progressive metabolic disorder -Defect in iduronate-2-sulfatase enzyme

1. In early life, chronic runny nose, ear infection, hernia
2. 2-4 yeards old, cognitive delay and unusual face features
3. Large liver and spleen from GAG storage, umbilical hernia, airway obstruction, thick nasal secretions
4. Stiff joints, behavoiral problems, hyperactivity
5. Shorter than non-affected sibilings, scoliosis, hearing loss, heart conditions

-Glycoproteins determine blood grouping A, B, O (with O being silent)
-If you don't make A or B, body will attack

-Enzyme aldose reductase catalyzes reduction of glucose into sorbitol
-High glucose activates this enzyme
-Sorbitol dehydrogenase turns sorbitol into fructose (which can then be used to make pyruvate to break down glucose)
-Too much glucose favors production of sorbitol
-Eye has low sorbitol dehydrogenase activity leading to glycation of proteins and formation of cateracts