Chapter 19 Biomolecules: Amino Acids, Peptides, and Proteins 19.1 Structures of Amino Acids 19.2 Isoelectric Points 19.3 Peptides and Proteins 19.4 Peptide.

Slides:



Advertisements
Similar presentations
Section B Protein Structure
Advertisements

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.
Functions of Proteins 20.2 Amino Acids 20.3 Amino Acids as Acids and Bases Chapter 20 Amino Acids and Proteins.
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,
By: Jean Turber, Kaitlin Clark & Kurstyn Pfleegor
LESSON PLAN 1 2 Introduction to biochemistry I and II 2,3 2+1
Protein: MONOMER – AMINO ACID. What is protein? Proteins are polymers of amino acids. Primary Structure Secondary Structure Tertiary Structure Quaternary.
Chapter 19, Unnumbered Figure 1, Page 701
Peptides and Proteins 20 amino acids are commonly found in protein. These 20 amino acids are linked together through "peptide bond" forming peptides and.
Protein: MONOMER – AMINO ACID
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
Functional Diversity of Proteins u Catalysis: Enzymes: amylase, pepsin, lipase u Transport: hemoglobin, serum albumin u Nutrient and Storage: egg albumin,
Chapter 18 Amino Acids, Proteins and Enzymes. Amino Acids 20 amino acids; all are α-amino acids:
Uncommon Amino Acids, Amino Acids Forming Proteins & Primary Structure of a Protein ( ) pg By: Emily, Kennedy.
Peptides and Proteins 20 amino acids are commonly found in protein. These 20 amino acids are linked together through "peptide bond" forming peptides and.
Chapter 14 Proteins Chemistry 20. Function of proteins Fibrinogen helps blood clotting.
The Organic Chemistry of Amino Acids,
Proteins – Amides from Amino Acids
Chapter 24 Amines Synthesize m-ethylphenol from benzene
Proteins Structure of proteins
Chapter 20 and GHW#10 Questions Proteins. Naturally occurring bioorganic polyamide polymers containing a sequence of various combinations of 20 amino.
Amino Acids. Amino Acid Structure Basic Structure: – (α) Carbon – Carboxylic Acid Group – Amino Group – R-group Side Chain Determines properties of Amino.
Chapter 18 Amino Acids, Peptides, and Proteins ( 氨基酸、肽、蛋白质 )
Uncommon amino acids, amino acids forming proteins, and primary structure of a protein Sections By Melissa Myers, Caroline Stepanik, and Jade.
General method for synthesis of azo dyes Add a cold aqueous solution of sodium nitrite slowly (with cooling and stirring) to a cold solution of the amine.
Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah
Fundamentals of Protein Structure
Chapter 26: Biomolecules: Amino Acids Peptides and Proteins
Chapter Proteins: Secondary, Tertiary, Quaternary, and Denaturation.
Amino Acids, Peptides, and Proteins. Introduction to Amino Acids  There are about 26 amino acids, many others are also known from a variety of sources.
Energy and Proteins
Amino acids Common structure of 19 AAs H3N+H3N+ COO - R H C Proline.
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.
Organic chemistry for medicine and biology students Chem 2311 Chapter 17 Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah Islamic University.
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.
Proteins  Are the most diverse biomolecules. They make up muscles, skin, hair, enzymes, hormones, hemoglobin, and antibodies.  The basic structure unit.
Chapter 10 Proteins. Chapter 102  Introduction  The three major groups of biological polymers are polysaccharides, proteins and nucleic acids  Proteins.
AMINO ACIDS and PROTEIN
Chapter 26 Biomolecules: Amino Acids, Peptides, and Proteins Amino Acid Peptide 2~50 Protein 50.
단백질의 다양성 ( 그림 5.1) 5.1 아미노산 - 아미노산 이름 및 약어 ( 표 5.1), 표준아미노산 ( 그림 5.2), - 일반구조 ( 그림 5.3): α- 탄소원자, 곁사슬, 카르복실기, 아미노기 - 프로린은 고리모양 ( 곁사슬과 아미노질소사이 ) -pH7 에서.
Biomolecule Amino Acids, Peptides, and Proteins Lecture 5 Dr. Aparna Islam 1.
Amino Acids carboxylic acid amine R varies with amino acid R = H
Amine R group Alpha Carbon Carboxylic Acid. Nonpolar side chains.
Protein chemistry Lecture Amino acids are the basic structural units of proteins consisting of: - Amino group, (-NH2) - Carboxyl group(-COOH)
Chapter 22 The Organic Chemistry of Amino Acids, Peptides, and Proteins Paula Yurkanis Bruice University of California, Santa Barbara.
Chapter 15 Biomolecules: Amino Acids, Peptides, and Proteins
Chemical synthesis of Peptide
Proteins Proteins are long polymers made up of 20 different amino acid monomers They are quite large, with molar masses of around 5,000 g/mol to around.
Proteins.
Protein Structure and Enzymes
Chapter 15 Biomolecules: Amino Acids, Peptides, and Proteins
Figure Number: 23-00CO Title: Oxidized Glutathione
Fundamentals of Organic Chemistry
Amino acids R-groups non-polar polar acidic basic proteins
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,
Amino acids R-groups non-polar polar acidic basic proteins
Fundamentals of Organic Chemistry
Fundamentals of Organic Chemistry
Fundamentals of Organic Chemistry
Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah
Amino acids, Peptides and Proteins By Prof. Dr. Adel M. Awadallah
Fundamentals of Organic Chemistry
Proteins Biopolymers of amino acids
Fundamentals of Organic Chemistry
Presentation transcript:

Chapter 19 Biomolecules: Amino Acids, Peptides, and Proteins 19.1 Structures of Amino Acids 19.2 Isoelectric Points 19.3 Peptides and Proteins 19.4 Peptide Synthesis 19.5 Classification of Proteins 19.6 Protein Structure

Amino acids ( 氨基酸 ): Alanine ( 丙氨酸 ) Peptides ( 肽 ): Many Chains with fewer than 50 amino acids Amide bonds Protein: ( 蛋白质 ) For larger chains

19.1 Structures of Amino Acids Dipolar ionZwitterion ( 偶极分子 ) Amino acids are amphoteric ( 两性离子 ): In base solution: In acid solution:

20α- amino cids found in protein. 19 of the 20amino acids are primary amines; Proline ( 脯氨酸 ) is a secondary amine. P476,Table 15.1 Differ only in the nature of side chain. Glycine ( 甘氨酸 ) (S)-Alanine L- Alanine (S)-Phenylalanine L-Phenylalanine (s)-Serine L-Serine L-Glycer- aldehyde

Aspatic acid ( 天冬氨酸 ) Glutamic acid ( 谷氨酸 ) Acidic Lysine ( 赖氨酸 ) arginine ( 精氨酸 ) Histidine ( 组氨酸 ) basic The others are neutral amino acids Isoelectric Points ( 等电点 ) pH Low pH (protonated) High pH (deprotonated)

Isoelectric Points (pI): At some intermediate pH, the concentration of the dipolar ion is maximal, the concen- trations of the anions and cations are equal. pI pH=5.0~5.6 Neutral amino acid: acidic amino acid: pI at lower pH basic amino acid:pI at higher pH Separation of a mixture of amino acids by Electrophoresis ( 电泳 ). -+ Lysine pI=9.74 Glycine pI=5.97 Aspartic acid pI=2.77 Paper strip at pH=5.97

C-terminal Amino acids polymers linked together by amide bonds. Peptide bond 19.3 Peptides and Proteins Alainine(Ala)Serine(Ser) Alanylserine(Ala-Ser) ( 丙氨酰 - 丝氨酸 )( 丙 - 丝二肽 ) Dipeptide ( 二肽 ) Tripeptide ( 三肽 ) Proteins: MW: >10000 N-terminal

19.4 Peptide Synthesis 1.Protection of the amino group by BOC group: Ex.: Synthesis of Alanine-Leucine: Alanine Di-tert-butyldicarbonateBoc-Ala 2. Protection of the carboxyl group by treatment with methanol or benzyl alcohol: BOC group can be removed by CF 3 COOH The groups can easily be removed by NaOH(aq).

3. The two protected amino acids are coupled using DCC. Dicyclohexylcarbodiimide (DCC) ( 二环己基碳二亚胺 ) 4. Removal of the BOC group. 5. Removal of ester group.

19.5 Classification of Proteins Classification according to the composition 1. Simple proteins: Blood serum albumin ( 血清蛋白 ), Globin ( 球蛋白 ). 2. Conjugated proteins ( 结合蛋白 ) : Glycoprotein ( 糖蛋白 ), Hemoglobin ( 血红蛋白 ) Classification according to the three-dimensional shape 1. Fibrous proteins: Collagen ( 胶原蛋白 ), keratin ( 角蛋白 ). Tough and insoluble in water.

2. Globular proteins: Hemoglobin, Insulin ( 胰岛素 ), Enzymes ( 酶 ). Soluble in water Protein Structure The primary structure of a protein: The amino acid sequence. The secondary structure of a protein: The segments of the peptide backbone ( 肽链 ). The tertiary structure of a protein: The three-dimensional shape of the entire protein molecule coiled.

Two kinds of The secondary structure of a protein: 1. α-Helix (α- 螺旋 ) α-Keratin (α- 角蛋白 )

2. β-Pleated sheet ( β- 折叠型 ) The β-Pleated sheet structure present in silk fibroin ( 蚕丝蛋白 )