Building Blocks - Amino Acids, Carbohydrates, and Vitamins

How are carbon atoms identified in a compound?

- Carbon atoms are numbered, starting with the carbon atoms with the most oxidized group

- Carbon atoms are given Greek letters, starting with the carbon next to carbon atom with most oxidized group

What are the simplest carbohydrates known as?

Monosaccharides

What is the empirical formula for monosaccharides?

CnH2nOn

Monosaccharides with 3, 4, 5, 6, & 7 carbon atoms are known as....

Trioses, tetroses, pentoses, hexoses, and heptoses

Simplest sugars can either be...

ketoses or aldoses

What is an isomer?

Compounds composed of the same elements, in the same number, but organized differently through bonding or 3-D spatial arrangement.

What is a chiral center?

A carbon atom with four different functional groups attached to it (asymmetrical center)

What two forms can a simple sugar exist in?

D or L enantiomers (stereoisomers).

What is an enantiomer?

Non superimposable mirror images

Sugars in the human tissue are in the ____ form

D

What are epimers?

Stereoisomers that differ in the position of the hydroxyl group at only one of the asymmetric carbons

Monosaccharides form _______ structures

ring

Six member rings structures of hexoses are knows as __________, while five member ring structures of pentoses and fructose are known as _________.

pyranoses

furanoses

Which carbon is known as the anomeric carbon?

Carbon 1

When the hydroxyl group bound to the anomeric carbon is below the plane, it is in the ______ form.

alpha

When the hydroxyl group of the anomeric carbon is above the plane, it is in the _______ form.

beta

What is it called when alpha and beta forms exist in equilibrium?

Mutarotation

Disaccharides contain two monosaccharides joined together by a......

Glycosidic link

How are glycosidic linkages formed?

The hydroxyl group of the anomeric carbon can react with OH or NH group to form a glycosidic linkage (O or N linked)

What types of glycosidic linkages are there?

1-6, 1-2, or 1-4 linkage. Alpha or Beta.

What is sucrose made up of?

Glucose and fructose joined by a 1a - 2B glycosidic linkage.

What is lactose made up of?

Galactose and glucose joined by a Beta 1-4 glycosidic linkage.

What is maltose made up of?

Two glucose molecules joined by an Alpha 1-4 glycosidic linkage.

What is an oligosaccharide

3 - 12 units of monosaccharides linked together

What is a polysaccharide?

- Linear or branched structures.

- More than 12 units.

- Examples: Starch, glycogen, cellulose

What are the 3 common modifications of carbohydrates?

Methylation, amination, and phosphorylation

What are Glycoproteins?

- Sugars attached to proteins.

- Found in cell membranes

- Functions in cell adhesion

Where do the sugars of glycoproteins attach to on the protein?

The amide nitrogen of asparagine or the oxygen atom of serine or threonine residues.

What are Proteoglycans?

- Repeating units of glycosaminoglycans (disaccharide containing a derivative of an amino sugar)

- Attached to protein - known as proteoglycans

What are proteoglycans important components of?

Cartilage

What are vitamins?

Organic molecules that are needed in small amounts in the diets of some higher animals. (Can not be synthesized in some higher organisms).

What can vitamin deficiency cause?

Diseases

How are vitamins grouped?

According to whether they're soluble in water or in nonpolar solvents. (water soluble and fat soluble vitamins).

Many enzyme cofactors are derived from....

water soluble vitamin precursors

What is the importance of cofactors?

They are required for some enzymes to function

Thiamine (B1)

Aldehyde Transfer

Consequence of Thiamine (B1) defficiency?

Beriberi (weight loss, heart problems, neurological disfunction)

Riboflavin (B2)

Oxidation-reduction

Consequence of Riboflavin (B2) deficiency?

Cheliosis and angular stomatitis (lesions of the mouth), dermatitis

Pyridoxine (B6)

Group transfer to or from amino acids

Consequence of Pyridoxine (B6) deficiency?

Depression, confusion, convulsions

Nicotinic acid (niacin) (B3)

Oxidation-reduction

Consequence of Nicotinic acid (niacin) (B3) deficiency?

Pellagra (dermatitis, depression, diarrhea)

Pantothenic acid (B5)

Acyl-group transfer

Consequence of Pantothenic acid deficiency?

Hypertension

Biotin (B7)

ATP-dependent carboxylation and carboxyl-group transfer

Consequence of Biotin (B7) deficiency?

Rash about the eyebrows, muscle, pain, fatigue (rare)

Folic acid (B9)

Transfer of one-carbon components - thiamine synthesis

Consequence of Folic acid (B9) deficiency?

Anemia, neural-tube defects in development

Cobalamin (B12)

Transfer of methyl groups; intramolecular rearrangements

Consequence of Cobalamin (B12) deficiency?

Anemia, pernicious anemia, methylmalonic acidosis

What cofactors are involved in Carbonyl/Acyl group transfer reactions?

Pantothenate (B5) and Thiamine (B1)

What cofactors are involved in oxidation-reduction reactions?

Nicotinic acid (B3) and Riboflavin (B2)

What are the building blocks of proteins?

Amino Acids

How many amino acids are there?

20 standard amino acids

Only ____ amino acids are incorporated into proteins

L

Nonpolar, Aliphatic Amino Acids

Glycine, Alanine, Proline, Valine, Leucine, Isoleucine

Polar, Uncharged Amino Acids

Asparagine, Glutamine, Serine, Threonine

Acids and Basic Amino Acids

Aspartate, Glutamate, Arginine, Lysine, Histidine

Aromatic Amino Acids

Phenylalanine, Tyrosine, Tryptophan

Sulfur Containing Amino Acids

Methionine and Cysteine

Amino acids and heterocyclic rings contain nitrogens, which carry a __________ charge at neutral pH.

positive

Nucleosides consist of a ______________ _______ attached to a sugar.

heterocyclic ring

A nucleoside plus ___________ is a nucleotide

phosphate