protein 2 chemistry of amino acida by dr ashok kumar j

1 Dr. Ashok Kumar J; IMS; MSU

Macro

molecules

Amino acid

Polymer of Amino acids

Small Molecules

Biomolecules

2Dr. Ashok Kumar J; IMS; MSU

C

R

NH2C = O O-

General structure of amino acid:

carboxyl groups

Side chain group

Individual amino acids differ from each other with respect to their side chain group


Amino acids present in proteins are α - amino acids


D- amino acid L- amino acid

All amino acids present in proteins are L-α-amino acids

All amino acids present in proteins are L-α-amino acids


• About 300 amino acids occur in nature

• Subset of only 20 constitute the monomer units of proteins

“Standard Amino acids”

?

6Dr. ASHOKKUMAR. J.; Professor: Dept. of

Biochemistry.

Glycine Gly G

Alanine Ala A

Valine Val V

Leucine Leu L

Isoleucine Ile I

Serine Ser S

Threonine Thr T

Phenylalanine

Phe F

Tyrosine Tyr Y

Tryptophan Trp W

Glutamate Glu E

Aspartate Asp D

Glutamine Gln Q

Aspargine Asn N

Arginine Arg R

Lysine Lys K

Histidine His H

Cysteine Cys C

Methionine Met M

Proline Pro P7

Dr. ASHOKKUMAR. J.; Professor: Dept. of

Biochemistry.


Classification of Amino acids1.Based on the structure

Mono amino Monocarboxylic amino acids

Branched chain amino acids

Simple amino acids

Aromatic amino acids


PHENYLALANINE TYROSINE TRYPTOPHAN

Monoamino monocarboxylic amino acids

Sulfur containing amino acids


METHIONINE CYSTEINE


Dr. Ashok Kumar J; IMS; MSU11

Diamino dicarboxylic acidsCystine

Cysteine

Hydroxyl group containing amino acids


SERINE THREONINE


Amino acid amides


ASPARAGINEGLUTAMINE


Acidic amino acids


ASPARTATE

GLUTAMATE

Monoamino dicarboxylic amino acids

Basic amino acids


HISTIDINE LYSINE ARGININE

Diamino monocarboxylic amino acids

Based on the side chain polarity


Based on PolarityNonpolar amino

acids


Alanine

Valine Leucine

Isoleucine

Methionine

Phenylalanine

Tryptophan

Proline

amino acids withpolar sidechain with no charge on the side chain


Glycine

Polar amino acids with – ve or + ve charge


ClassificationBased on the nutritional

requirement


ClassificationBased on the Metabolic fate


D- amino acids• Actinomycin –D• Valinomycine• Gramicidin –S• D –Glutamic acid & D- Alanine

of bacterial cell wall


Acid – Base Properties of amino acid

Low pH

High pH26

Dr. ASHOKKUMAR. J.; Professor: Dept. of

Biochemistry.

amino acids act both as acid and base depending upon the

surrounding environment

Ampholytes

At isoelectric pH -Minimum solubility-Immobile in the electrical field

+ve charge – pH below the isoelectric pH-ve charge – pH above the isoelectric pH27 Dr. Ashok Kumar J; IMS; MSU

pH at which amino acids have equal number of positive and negative charges is called isoelectric pH [pI]

Thank you

Ref :


protein 2 chemistry of amino acida by dr ashok kumar j

Health & Medicine

ashok kumar j ims msu21

amino acids5

amino acids4

amino acids actboth

amino acidsserine threonine12

classification of amino

polar amino acidswith

isoelectric phve charge