This document discusses the structure of proteins at four levels: primary, secondary, tertiary, and quaternary. The primary structure refers to the amino acid sequence in the polypeptide chain. Secondary structures include alpha helices and beta sheets formed by hydrogen bonding between amino acids. Tertiary structure describes the overall 3D shape of the protein formed by interactions between amino acid side chains. Quaternary structure applies to proteins composed of multiple polypeptide subunits that combine through non-covalent bonds. The structures are determined through techniques like X-ray crystallography and NMR spectroscopy.
Chemistry of amino acids with their clinical applicationsrohini sane
A comprehensive presentation on Chemistry of Amino acids with their clinical applications for MBBS , BDS, B Pharm & Biotechnology students to facilitate easy- learning.
Chemistry of amino acids with their clinical applicationsrohini sane
A comprehensive presentation on Chemistry of Amino acids with their clinical applications for MBBS , BDS, B Pharm & Biotechnology students to facilitate easy- learning.
I shikha popali and my colleague harshpal singh wahi presents a presentation "RECENT DEVELOPMENT IN DRUG DESIGN AND DISCOVERY " A detail account on protein structure is given
Amino acisd structure
Peptide bond formation
Analysis of protein Structure- X-ray Crystallography
Different structural levels of proteins with examples.
Importance of protein structure
Creutzfeldt-Jacob-Disease due to changes in normal protein conformation.
Title: Sense of Smell
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 primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
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.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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
3. • Proteins are an important class of
biological macromolecules
which are the polymers of amino
acids.
• Biochemists have distinguished
several levels of structural
organization of proteins. They
are:
– Primary structure
– Secondary structure
– Tertiary structure
– Quaternary structure
INTRODUCTION
4. PRIMARY STRUCTURE
• The primary structure of protein refers to the sequence of amino
acids present in the polypeptide chain.
• Amino acids are covalently linked by peptide bonds.
• Each component amino acid in a polypeptide is called a “residue” or
“moiety”
• By convention, the 10 structure of a protein starts from the amino-
terminal (N) end and ends in the carboxyl-terminal (C) end.
5. IMPORTANCE OF PRIMARY STRUCTURE
• To predict 20 and 30 structures from sequence homologies with
related proteins. (Structure prediction)
• Many genetic diseases result from abnormal amino acid sequences.
• To understand the molecular mechanism of action of proteins.
• To trace evolutionary paths.
• End group analysis – Edman degradation.
• Gene sequencing method.
METHODS OF AMINO ACID SEQUENCE DETERMINATION
6. SECONDARY STRUCTURE
• Localized arrangement of adjacent amino acids formed as the polypeptide
chain folds.
• It consists of
• Linus Pauling proposed some essential features of peptide units and
polypeptide backbone. They are:
– The amide group is rigid and planar as a result of resonance. So rotation
about C-N bond is not feasible.
– Rotation can take place only about N- Cα and Cα – C bonds.
– Trans configuration is more stable than cis for R grps at Cα
• From these conclusions Pauling postulated 2 ordered structures α helix and
β sheet
α-helix
β-pleated sheet
β-bends
Non repetitive structures
Super secondary structures
7. POLYPEPTIDE
CHAIN CONFORMATIONS
• The only reasonably free movements
are rotations around the C α-N bond
(measured as ϕ ) and the C α-C bond
(measured as Ѱ).
• The conformation of the backbone
can therefore be described by the
torsion angles (also called dihedral
angles or rotation angles)
8. • Spiral structure
• Tightly packed, coiled polypeptide
backbone core.
• Side chain extend outwards
• Stabilized by H bonding b/w
carbonyl oxygen and amide
hydrogen.
• Amino acids per turn – 3.6
• Pitch is 5.4 A
• Alpha helical segments are found in
many globular proteins like
myoglobins, troponin- C etc.
ALPHA HELIX
H bonding
9. • Formed when 2 or more polypeptides
line up side by side.
• Individual polypeptide - β strand
• Each β strand is fully extended.
• They are stabilized by H bond b/w N-H
and carbonyl grps of adjacent chains.
BETA PLEATED SHEET
2 types
Parallel Anti -Parallel
N C N
N NC
C
C
12. BETA BENDS
• Permits the change of direction of the
peptide chain to get a folded structure.
• It gives a protein globularity rather than
linearity.
• H bond stabilizes the beta bend
structure.
• Proline and Glycine are frequently
found in beta turns.
• Beta turns often promote the formation
of antiparallel beta sheets.
• Occur at protein surfaces.
• Involve four successive aminoacid
residues
13. NON REPETITIVE STRUCTURES
• A significant portion of globular
protein’s structure may be irregular
or unique.
• They include coils and loops.
• Segments of polypeptide chains
whose successive residues do not
have similar ϕ and Ѱ values are
called coils.
• Almost all proteins with more than
60 residues contain one or more
loops of 6 to 16 residues, called Ω
loops.
Space-filling model of an Ω loop
14. TERTIARY STRUCTURE
• Tertiary structure is the three-
dimensional conformation of a
polypeptide.
• The common features of protein
tertiary structure reveal much about
the biological functions of the proteins
and their evolutionary origins.
• The function of a protein depends on
its tertiary structure. If this is disrupted,
it loses its activity.
15. DOMAINS
• Polypeptide chains containing more than ,200 residues usually
fold into two or more globular clusters known as domains.
• Fundamental functional and 3 dimensional structure of
proteins.
• Domains often have a specific function such as the binding of
a small molecule.
• Many domains are structurally independent units that have the
characteristics of small globular proteins.
The two-domain protein glyceraldehyde-
3-phosphate dehydrogenase.
NAD+
16. INTERACTIONS STABILIZING 30
STRUCTURE
• This final shape is
determined by a variety of
bonding interactions
between the "side chains"
on the amino acids.
• Hydrogen bonds
• Ionic Bonds
• Disulphide Bridges
• Hydrophobic Interactions:
18. DETERMINATION OF TERTIARY
STRUCTURE
• The known protein structures have come to light through:
• X-ray crystallographic studies
• Nuclear Magnetic Resonance studies
• The atomic coordinates of most of these structures are
deposited in a database known as the Protein Data Bank
(PDB).
• It allows the tertiary structures of a variety of proteins to be
analyzed and compared.
19. • The biological function of some
molecules is determined by multiple
polypeptide chains –
multimeric proteins.
• Arrangement of polypeptide sub unit
is called quaternary structure.
• Sub units are held together by non
covalent interactions.
• Eg: Hemoglobin has the subunit
composition a2b2
QUATERNARY STRUCTURE
Quaternary structure of hemoglobin.
20. RECENT DEVELOPMENTS
• A team of scientists at The Scripps Research Institute and the
National Institutes of Health (NIH) has discovered the
structure of a protein – dynamin, that pinches off tiny pouches
from cell’s outer membranes.
• Scientists at the Institute of Structural and Molecular Biology
have revealed the structure of a complex protein called FimD
that acts as an assembly platform for the pili of cystitis
bacteria.
• Researchers from the Walter and Eliza Hall Institute have
found a structural surprise in a type of protein, Bcl-w ,that
encourages cell survival, raising interesting questions about
how the proteins function to influence programmed cell death.
21. CONCLUSION
• Proteins are extraordinarily complex molecules. Of all the
molecules encountered in living organisms, proteins have the
most diverse functions.
• So a basic understanding of the structure of proteins is
necessary to comprehend its role in organisms.
• Further researches will provide more insight into the structure
of several other proteins in the coming year.
22. REFERENCE
• Voet, Donald; Voet Judith. Biochemistry, 3rd edition, John
Wiley and sons.
• Champe, Pamela.C, Harvey, Richard A, Ferrier Denise R
(2005). Lippincott’s Illustrated Reviews: Biochemistry, 3rd
edition. Lippincott William and Wilkins.
• McKee Trudy, McKee James R (2003), Biochemistry: The
molecular basis of life, 3rd edition, McGraw Hill.
• http://esciencenews.com/articles/2011/06/01/new.antibiotics.a.
step.closer.with.discovery.bacterial.protein.structure
• http://www.eurekalert.org/pub_releases/2010-04/sri-
srs042610.php
• http://www.physorg.com/news/2011-10-cell-survival-protein-
reveals.html