Here are the key points from the protein separation methods reading:
- There are several methods used to separate proteins including precipitation, electrophoresis, chromatography, and ultracentrifugation.
- Precipitation separates proteins based on differences in solubility at various pH, temperatures, or in the presence of salts, organic solvents, or other reagents. It is a crude separation method.
- Electrophoresis separates proteins based on their charge and size by applying an electric current through a gel or liquid. Common types are PAGE and SDS-PAGE.
- Chromatography separates proteins based on differences in how they interact with a stationary phase compared to a mobile phase as they flow through a column. Key types are ion-exchange
a) Definition, classification, structure, stereochemistry and reactions of amino acids;
b) Classification of proteins on the basis of solubility and shape, structure, and biological functions. Primary structure - determination of amino acid sequences of proteins, the peptide bond, Ramachandran plot.
c) Secondary structure - weak interactions involved - alpha helix and beta sheet and beta turns structure, Pauling and Corey model for fibrous proteins, Collagen triple helix, and super secondary structures - helix-loop-helix.
d) Tertiary structure - alpha and beta domains. Quaternary structure - structure of haemoglobin, Solid state synthesis of peptides, Protein-Protein interactions, Concept of chaperones.
a) Definition, classification, structure, stereochemistry and reactions of amino acids;
b) Classification of proteins on the basis of solubility and shape, structure, and biological functions. Primary structure - determination of amino acid sequences of proteins, the peptide bond, Ramachandran plot.
c) Secondary structure - weak interactions involved - alpha helix and beta sheet and beta turns structure, Pauling and Corey model for fibrous proteins, Collagen triple helix, and super secondary structures - helix-loop-helix.
d) Tertiary structure - alpha and beta domains. Quaternary structure - structure of haemoglobin, Solid state synthesis of peptides, Protein-Protein interactions, Concept of chaperones.
OBJECTIVES Digestion and absorption of proteins and amino acids Introduction to amino acids, structure and types Amino acid and nutrition General.
The amino acids undergo certain common reactions like transamination followed by deamination for the liberation of ammonia. The amino group of the amino acids is utilized for the formation of urea which is an excretory end product of protein metabolism.
1. General Structure of Amino Acids
2. Amino acids classification based on:
- Standard and Non-standard amino acids (AA)
- Essential and non-essential AA
- Ketogenic and Glycogenic AA
- Side chain functional group
3. Function of essential Amino Acids
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Example
General structure of amino acid
Specific learning objective (SLO): Amino acid as Ampholytes (acid and base), Zwitter ions.
Classification of amino acid on the basis of side chain, chemical composition, Nutritional Requirement and metabolic fate.
Derived amino acids.
Optical properties of amino acids.
Acid-Base properties and Buffer characteristic.
Biological Important Peptides
Proteins based on nutritional value
OBJECTIVES Digestion and absorption of proteins and amino acids Introduction to amino acids, structure and types Amino acid and nutrition General.
The amino acids undergo certain common reactions like transamination followed by deamination for the liberation of ammonia. The amino group of the amino acids is utilized for the formation of urea which is an excretory end product of protein metabolism.
1. General Structure of Amino Acids
2. Amino acids classification based on:
- Standard and Non-standard amino acids (AA)
- Essential and non-essential AA
- Ketogenic and Glycogenic AA
- Side chain functional group
3. Function of essential Amino Acids
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acidExamples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Examples in biomolecules - proteins, lipids, carbohydrates, and nucleic acid
Example
General structure of amino acid
Specific learning objective (SLO): Amino acid as Ampholytes (acid and base), Zwitter ions.
Classification of amino acid on the basis of side chain, chemical composition, Nutritional Requirement and metabolic fate.
Derived amino acids.
Optical properties of amino acids.
Acid-Base properties and Buffer characteristic.
Biological Important Peptides
Proteins based on nutritional value
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
2. What are proteins?
• Proteins are large, complex molecules that play many critical roles in the
body.
• They do most of the work in cells and are required for the structure,
function, and regulation of the body’s tissues and organs.
• Proteins are made up of hundreds or thousands of smaller units called
amino acids, which are attached to one another in long chains.
• There are 20 different types of amino acids that can be combined to make
a protein.
• The sequence of amino acids determines each protein’s unique 3-
dimensional structure and its specific function.
• Amino acids are coded by combinations of three DNA building blocks
(nucleotides), determined by the sequence of genes.
3. AMINO ACIDS
• Cells produce proteins with strikingly different properties
and activities by joining the same 20 amino acids in many
different combinations and sequences.
• This indicates that the properties of proteins are
determined by the physical and chemical properties of
their monomer units, the amino acids.
• Amino acids are the basic structural units of proteins
consisting of an amino group, (-NH2) a carboxyl (-COOH)
group a hydrogen (H) atom and a (variable) distinctive (R)
group.
• All of the substituents in amino acid are attached
(bonded) to a central α carbon atom.
• This carbon atom is called α because it is bonded to the
carboxyl (acidic) group.
4. In neutral solution
(PH = 7), both the
α- amino and α
carboxyl group are
ionized resulting
the charged form
of an amino acids
called zwitterion
(dipolar) as shown
in the next slide.
Out of the 20 amino acids, proline is not an α amino
acid rather an α - imino acid. Except for glycine, all
amino acids contain at least one asymmetric carbon
atom (the α - carbon atom).
7. Classification of Amino Acids
They are classified based on;
• Structure
• Electrochemical classification
• Biological and physiological
• Metabolic fate
8. Structural classification: This classification is based on the side chain
radicals (R-groups)
R groups
with
Aliphatic side chains
e.g glycine, alanine,
valine, leucine,
isoleucine
Sulfur group:
cysteine,
methionine
Aromatic group;
phenylalanine,
tyrosine,
tryptophan,
Imino group;
proline
9. Electrochemical
Amino acids could also be classified based on their acid – base properties
Basic amino acids
1. Lysine
2. Arginine
Neutral amino acids
1. Asparagine
2. Serine
3. Threonine
4. Glutamine
Acidic amino acids
1. Glutamic acid
2. Aspartic acid
10. Biological
This classification is based on the functional property of amino acids for the organism.
• Essential: Amino acids which are not synthesized in the body and must be provided in the
diet to meet an animal’s metabolic needs are called essential amino acids.
• Non essential: These amino acids are need not be provided through diet, because they
can be biosynthesized in adequate amounts within the organism.
• Semi-essential amino acids: they can be synthesized within the organism but their
synthesis is not in sufficient amounts. In that they should also be provided in the diet.
Essential Non-essential Semi-essential
Arginine, histidine,
leucine, isoleucine,
lysine, methionine,
phenylalanine,
Threonine, Tryptophan,
Valine
Alanine, Asparagine,
aspartine, cysteine,
glutamic acid,
glutamine, glycine,
proline, serine, tyrosine
Histidine, Arginine
11. Metabolic fate of each amino acid
Amino acids can be classified here as Glucogenic (potentially be converted to
glucose), ketogenic (potentially be converted to ketone bodies) and both glucogenic
and ketogenic.
Glucogenic amino acids: Those amino acids in which their carbon skeleton gets
degraded to pyrurate, α ketoglutarate, succinyl CoA, fumrate and oxaloacetate and
then converted to Glucose and Glycogen, are called as Glucogenic amino acids.
These include:- Alanine, cysteine, glycine, Arginine, glutamine, Isoleucine, tyrosine
Ketogenic amino acids: Those amino acids in which their carbon skeleton is
degraded to Acetoacetyl CoA, or acetyl CoA. then converted to acetone and β-
hydroxy butyrate which are the main ketone bodies are called ketogenic amino acids.
These includes:- Phenylalanine, tyrosine, tryptophan, isoleucine, leucine, and lysine.
These amino acids have ability to form ketone bodies which is particularly evident in
untreated diabetes mellitus in which large amounts of ketone bodies are produced by
the liver (i.e. not only from fatty acids but also from ketogenic amino acids)
12. Ketogenic and glucogenic amino acids: The division between ketogenic and
glucogenic amino acids is not sharp for amino acids (Tryptophan, phenylalanine,
tyrosine and Isoleucine are both ketogenic and glucogenic).
Some of the amino acids that can be converted in to pyruvate, particularly (Alanine,
Cysteine and serine, can also potentially form acetoacetate via acetyl CoA
especially in severe starvation and untreated diabetes mellitus.
13.
14. Peptides
• Proteins are macromolecules with a backbone formed by polymerization of
amino acids in a polyamide structure.
• These amide bonds in protein, known as peptide bonds formed by linkage of α -
carboxyl group of one amino acid with α- amino groups of the next amino acid
by amide bonds.
• During the formation of a peptide bond, a molecule of water is eliminated as
shown below:-
• A peptide chain consisting of two amino acid residues is called a dipeptide,
three amino acids
tripeptide (e. g Glutathione)
15.
16. Glutathione
• Glutathione is a tripeptide
formed from amino acids
glutamate, cysteine and
Glycine, linked together in
that order. The glutamate is
linked to cysteine through
the γ- carboxyl group and α
- amino group of cysteine.
• Here, the carboxyl group is
first activated by ATP to
form an acyl-phosphate
derivative which is then
attacked by cysteine amino
group then undergoes
condensation with glycine.
17. • The role of GSH as a reductant is extremely important particularly in the highly
oxidizing
environment of the erythrocyte.
• The sulfhydryl of GSH can be used to reduce peroxides formed during oxygen
transport. The resulting oxidized form of GSH consists of two molecules
disulfide bonded together (abbreviated GSSG).
• The enzyme glutathione reductase utilizes NADPH as a cofactor to reduce
GSSG back to two moles of GSH.
• Hence, the pentose phosphate pathway is an extremely important pathway of
erythrocytes for the continuing production of the NADPH needed by glutathione
reductase.
• In fact as much as 10% of glucose consumption, by erythrocytes, may be
mediated by the pentose phosphate pathway.
19. PROTEINS
• Proteins are macromolecules with a backbone formed by polymerization of
amino acids in a polyamide structure.
Class Assignment 2:
1. List functions of proteins (3 marks)
2. Using the flow chart on slide 18, describe the
classification of proteins (7 marks)
20. Protein Organization
Primary structure
The simplest level of protein structure, primary structure, is simply the
sequence of amino acids in a polypeptide chain.
For example, the hormone insulin has two polypeptide chains, A and B,
shown in diagram below.
(The insulin molecule shown here is cow insulin, although its structure is
similar to that of human insulin.) Each chain has its own set of amino acids,
assembled in a particular order.
For instance, the sequence of the A chain starts with glycine at the N-
terminus and ends with asparagine at the C-terminus, and is different from
the sequence of the B chain.
21.
22. • The sequence of a protein is determined by the DNA of the gene that
encodes the protein (or that encodes a portion of the protein, for multi-
subunit proteins).
• A change in the gene's DNA sequence may lead to a change in the
amino acid sequence of the protein.
• Even changing just one amino acid in a protein’s sequence can affect
the protein’s overall structure and function.
• For instance, a single amino acid change is associated with sickle cell
anemia, an inherited disease that affects red blood cells.
• In sickle cell anemia, one of the polypeptide chains that make up
hemoglobin, the protein that carries oxygen in the blood, has a slight
sequence change.
• The glutamic acid that is normally the sixth amino acid of the
hemoglobin β chain (one of two types of protein chains that make up
hemoglobin) is replaced by a valine.
23. Secondary Structure
• The next level of protein structure, secondary structure, refers to local folded
structures that form within a polypeptide due to interactions between atoms of
the backbone.
• (The backbone just refers to the polypeptide chain apart from the R groups – so
all we mean here is that secondary structure does not involve R group atoms.)
• The most common types of secondary structures are the α helix and the β
pleated sheet.
• Both structures are held in shape by hydrogen bonds, which form between the
carbonyl O of one amino acid and the amino H of another.
24.
25. Tertiary structure
• The overall three-dimensional structure of a polypeptide is called its tertiary
structure. The tertiary structure is primarily due to interactions between the R
groups of the amino acids that make up the protein.
• R group interactions that contribute to tertiary structure include hydrogen
bonding, ionic bonding, dipole-dipole interactions, and London dispersion
forces – basically, the whole gamut of non-covalent bonds.
• For example, R groups with like charges repel one another, while those with
opposite charges can form an ionic bond.
• Similarly, polar R groups can form hydrogen bonds and other dipole-dipole
interactions.
• Also important to tertiary structure are hydrophobic interactions, in which
amino acids with nonpolar, hydrophobic R groups cluster together on the
inside of the protein, leaving hydrophilic amino acids on the outside to interact
with surrounding water molecules.
26. • Finally, there’s one special type of covalent bond that can contribute to tertiary
structure: the disulfide bond.
• Disulfide bonds, covalent linkages between the sulfur-containing side chains of
cysteines, are much stronger than the other types of bonds that contribute to
tertiary structure.
• They act like molecular "safety pins," keeping parts of the polypeptide firmly
attached to one another.
27. Quaternary structure
• Many proteins are made up of a single polypeptide chain and have only three
levels of structure (the ones we’ve just discussed).
• However, some proteins are made up of multiple polypeptide chains, also
known as subunits. When these subunits come together, they give the protein
its quaternary structure.
• As mentioned earlier, hemoglobin carries oxygen in the blood and is made up of
four subunits, two each of the α and β types.
• Another example is DNA polymerase, an enzyme that synthesizes new strands
of DNA and is composed of ten subunits^55start superscript, 5, end superscript.
• In general, the same types of interactions that contribute to tertiary structure
(mostly weak interactions, such as hydrogen bonding) also hold the subunits
together to give quaternary structure
28.
29. Protein Denaturation (Reading
Assignment)
• The phenomenon of disorganization of native protein structure is known as
denaturation.
• Denaturation results in the loss of secondary, tertiary and quaternary
structureof proteins. This involves a change in physical, chemical and
biological properties of protein molecule
Agents of denaturation
• Physical agents: Heat, violent shaking, X-ravs,UV radiation.
• Chemical agents : Acids, alkalies, organic solvents(ether,alcohol), salts of
heavy metals (Pb, Hg), urea,salicylate.
30. Characteristics of denaturation
a) The native helical structure of protein is lost
b) The primary structure of a protein with peptide linkages remains intact i.e.,
peptide bonds are not hydrolysed.
c) The protein loses its biologicalactivity.
d) Denatured protein becomes insoluble in the solventin which it was originally
soluble.
e) The viscosity ol denatured protein (solution) increaseswhile its surface tension
decreases.
f) Denaturation is associated with increase in ionizable and sulfhydryl groups of
protein. This is due to loss of hydrogen and disulfide bonds.
g) Denatured protein is more easily digested. This is due to increased exposure of
peptide bonds to enzymes. Cooking causes protein denaturation and, therefore,
cooked food (protein)is more easily digested
31. h) Denaturation is usually irreversible. For instance, omelet can be prepared from an
egg (protein-albumin) but the reversal is not possible.
i) Careful denaturation is sometimes reversible (known as renaturation). Hemoglobin
undergoes denaturation in the presence of salicylate. By removal of salicylate,
hemoglobin is renatured.
j) Denatured protein cannot be crystallized
32. • Flocculation:
• lt is the process of protein precipitation at isoelectric pH.
• The precipitate is referred to as flocculum. Casein (milk protein) can be
easily precipitated when adjusted to isoelectric pH (4.6 by dilute acetic
acid.
• Flocculation is reversible.
• On application of heat, flocculum can be converted into an
irreversible mass, coagulum
Coagulation:
• The term 'coagulum' refers to a semi-solid viscous precipitate of protein.
reversible denaturation results in coagulation.
• Coagulation is optimum and requires lowest temperature at isoelectric
pH. Albumins and globulins (to a lesser extent) are coagulable proteins.
• Heat coagulation test is commonly used to detect the presence of
albumin in urine.
33. Protein Separation Methods (Reading
Assessment)
Group 1: Lydia, Brian, David (Protein Denaturation)
Group 2: Maxwell, Lennick, Gabriel, Peter, Reuben,
Dawn, Kevin, Eric, Ian (Protein separation methods)
Oral assessment (5 marks)