Organic chemistry for medicine and biology students Chem 2311 Chapter 17 Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah Islamic University.

Slides:



Advertisements
Similar presentations
Chemistry 2100 Lecture 10.
Advertisements

(carbon-based compounds)
Amino Acids and Proteins B.2. there are about 20 amino acids that occur naturally they are the basic “building blocks” of life/proteins.
Chapter 16 Amino Acids, Proteins, and Enzymes
H OH - 2 Charge: +1 Charge: 0 (When aa have a net charged of zero its called a Zwitterion ) Charge: -1 Low PHHigh PH Adding a base PH=1 PH=7 PH=12 Pka=10.
Chapter 19: Proteins CHEM 1152 Dr. Sheppard.
CHE 242 Unit VIII The Structure, Properties, Reactions and Mechanisms of Carboxylic Acids and Their Derivatives CHAPTER TWENTY-FOUR Terrence P. Sherlock.
Organic Chemistry 4 th Edition Paula Yurkanis Bruice Chapter 23 Amino Acids, Peptides, and Proteins Irene Lee Case Western Reserve University Cleveland,
AMINO ACIDS AND PROTEINS
By: Jean Turber, Kaitlin Clark & Kurstyn Pfleegor
Unit 2 – Chemistry of Life.  
BIOCHEMISTRY. PROTEINS Natural polymers C,H,O,N,(S) Monomer is Amino Acids Growth Repair Hormones Enzymes Antibodies Energy Source.
Proteins and Enzymes Nestor T. Hilvano, M.D., M.P.H. (Images Copyright Discover Biology, 5 th ed., Singh-Cundy and Cain, Textbook, 2012.)
Diverse Macromolecules. V. proteins are macromolecules that are polymers formed from amino acids monomers A. proteins have great structural diversity.
19.1 Proteins and Amino Acids
Proteins Major group of biological molecules. Proteins Monomers: amino acids ▫Always contain an amino group and carboxylic acid group Polymers: peptides.
Chapter 19 Amino Acids and Proteins
Hannah Barreca Daria Lukasz Ian Reucroft Roshelle Belfer Stephanie Puthumana.
Amino Acids and Proteins B.2. Properties of 2-amino acids (B.2.2) Zwitterion (dipolar) – amino acids contain both acidic and basic groups in the same.
Proteins Amino acids, peptide bonds, primary, secondary, tertiary and quaternary structures.
PROTEINS. Learning Outcomes: B4 - describe the chemical structure of proteins List functions of proteins Draw and describe the structure of an amino acid.
Chapter 14 Proteins Chemistry 20. Function of proteins Fibrinogen helps blood clotting.
The Organic Chemistry of Amino Acids,
Chapter 24 Amino Acids and Proteins Created By Prof. Gary F. Porter, Ph.D. Copyright © 2014 by John Wiley & Sons, Inc. All rights reserved.
Chapter 20 and GHW#10 Questions Proteins. Naturally occurring bioorganic polyamide polymers containing a sequence of various combinations of 20 amino.
Uncommon amino acids, amino acids forming proteins, and primary structure of a protein Sections By Melissa Myers, Caroline Stepanik, and Jade.
Lecture Eleven : Amino Acids, Peptides and Proteins Convener : Dr. Fawaz Aldabbagh First Year Organic Chemistry Biological Chemistry.
27.19 Secondary Structures of Peptides and Proteins.
Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah
Properties and structure:  Are carboxylic acids with α - amino group.  Are the basic building blocks of proteins.  Nearly all have an asymmetric.
Protein- Secondary, Tertiary, and Quaternary Structure.
General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc.1 Chapter 19 Amino Acids and Proteins 19.2 Amino Acids as Zwitterions.
Option B Biochemistry Jeff Venables Northwestern High School.
Key area: Proteins Overview In this section, study the structure and function of proteins. Learn about how they are formed from amino acids in condensation.
Module Biological Molecules Proteins By Ms Cullen.
A PRESENTATION ON AMINO ACIDS AND PROTEINS PRESENTED BY SOMESH SHARMA Chemical Engineering Arham Veerayatan Institute of Engineering Technology.
1 Chapter 19 Amino Acids and Proteins 19.1 Proteins and Amino Acids 19.2 Amino Acids as Acids and Bases Copyright © 2007 by Pearson Education, Inc. Publishing.
OPTION B: Human Biochemistry B2: Proteins. Objectives Jan 3, 2010 B.2.1 Draw the general formula of 2-amino acids B.2.2 Describe the characteristic properties.
Chapter 10 Proteins. Chapter 102  Introduction  The three major groups of biological polymers are polysaccharides, proteins and nucleic acids  Proteins.
Peptides to Proteins. What are PROTEINS? Proteins are large, complex molecules that serve diverse functional and structural roles within cells.
Protein chemistry Lecture Amino acids are the basic structural units of proteins consisting of: - Amino group, (-NH2) - Carboxyl group(-COOH)
Proteins. Chemical composition of the proteins. Properties of α- amino carboxylic acids.
Proteins Proteins are the building materials for the body.
Proteins. Chemical composition of the proteins
Chapter 22 The Organic Chemistry of Amino Acids, Peptides, and Proteins Paula Yurkanis Bruice University of California, Santa Barbara.
CHM 708: MEDICINAL CHEMISTRY
Chapter 19 Amino Acids and Proteins
Amino acids.
PROTEINS and ENZYMES!.
Organic Compounds: Proteins
Amino Acids and Proteins
Proteins.
Fundamentals of Organic Chemistry
Diverse Macromolecules
BIO201/BBT101 SPRING 2018 Introduction to Biochemistry & Biotechnology
Chapter 19: Proteins.
Proteins Describe what a protein is and give examples of what they are used for. Describe the structure and shape of the different types of proteins. Explain,
Fundamentals of Organic Chemistry
Fundamentals of Organic Chemistry
Daily Science In forming a protein, why is it important that every amino acid has the same structure of a carboxyl group on one side and amino group on.
Fundamentals of Organic Chemistry
AMIDES.
Proteins.
Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah
Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah
Dr. J. Venables Northwestern High School
Fundamentals of Organic Chemistry
Proteins Biopolymers of amino acids
Fundamentals of Organic Chemistry
2.4 - Proteins.
Presentation transcript:

Organic chemistry for medicine and biology students Chem 2311 Chapter 17 Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah Islamic University of Gaza

Amino acids: Carboxylic acids with an  -amino group Peptides: consists of few linked amino acids Proteins: composed of  -amino acids The amino acids obtained from Protein hydrolysis are: *  -amino acids * Optically active (except glycine) * Have the L-configuration relative to glycerladehyde

* 20 amino acids are commonly found in proteins * 12 can be synthesized in the body 8 (essential amino acids) cannot be synthesized in the body, and must be obtained from the diet in the form of proteins A three letter abbreviation is used when writing the formulas of peptides A one letter abbreviation is used to describe the amino acid sequence in a protein

The acid base properties of amino acids COOH (acidic group),,,, NH 2 (basic group) Amino acids are better represented by a dipolar ion structure (zwitterions)

Example

Amino acids in electric fields Isoelectric point: is the pH at which the amino acid will be dipolar and have a net charge equal to zero. It will not move toward either electrode

Electrophoresis Electrophoresis: is a method for seperating amino acids and proteins based on their charge differences Example pI for aspartic acid 3.0 pI for alanine 6.0 At pH 5 Aspartic acid is negative alanine is posiive So they can be seperated Problem Glycine and lysine at pH 7 Phenylalanine, leucine and proline at pH 6

Reactions of amino acids

Peptide Synthesis Linking amino acids in a controlled manner

Proteins Proteins are major components of: Structural tissues (muscle, skin, nails, hair) Transport molecules (Hemoglobin) Enzymes (biological catalysts) Structure of Peptides and Proteins: Primary structure: Amino acids and sequence Secondary, tertiary and quaternary structures: three dimensional aspects of the structure

The primary structure The backbone of proteins is a repeating sequence of one nitrogen and two carbon atoms Hydrolysis of proteins and peptides (6 M HCl at 110 o C for 24 hours) Amino acid analyzer

Sequence Determination Sanger Method: Identification of the N-terminal amino acid

Edman’s reagent A reagent that clips off just one amino acid at a time from the end of the chain

Cleavage of selected peptide bonds Proteins containing several hundred amino acid units are better cleaved at particular peptide bonds using certain chemicals or enzymes, then they are sequenced by Edman method

To add more amino acids, we must selectively remove one of the protecting groups and join the next amino acid Oxytocin (prepared by Vincent du Vigneaud – Nobel 1955) Oxytocin produced by posterior pituitary gland. It regulates uterine contraction and lactation and may be administered when it is necessary to induce labor at childbirth

Secondary Structure of Proteins Many polymers have been isolated in pure crystalline form and are polymers with very well defined shapes. Geometry of the peptide bond Planar geometry Amide C-N bond (1.32 A) is shorter than normal C-N bond (1.47 A) Rotation around the amide bond is restricted (double bond character)

The  -helix

The pleated Sheet

Tertiary structure: Fibrous and globular proteins Three dimensional structure of the protein which results from the: a)R groups b) the disulfide bonds For example turns are found at or near proline (No H bonding)

Quaternary Protein structure