Homology modeling, also known as comparative modeling of protein, refers to constructing an atomic-resolution model of the "target" protein from its amino acid sequence and an experimental three-dimensional structure of a related homologous protein.
Prediction of the three dimensional structure of a given protein sequence i.e. target protein from the amino acid sequence of a homologous (template) protein for which an X-ray or NMR structure is available based on an alignment to one or more known protein structures
HERE IN THIS PRESENTATION HY HOMOLOGY MODELING IS EXPLAIN , WITH EXAMPLES OF PROTEIN PRIMARY AND SECONDARY, SHOWING THE IMAGES FORM WHICH MAKES EASY TO UNDERSTAND
Prediction of the three dimensional structure of a given protein sequence i.e. target protein from the amino acid sequence of a homologous (template) protein for which an X-ray or NMR structure is available based on an alignment to one or more known protein structures
HERE IN THIS PRESENTATION HY HOMOLOGY MODELING IS EXPLAIN , WITH EXAMPLES OF PROTEIN PRIMARY AND SECONDARY, SHOWING THE IMAGES FORM WHICH MAKES EASY TO UNDERSTAND
Ab Initio Protein Structure Prediction is a method to determine the tertiary structure of protein in the absence of experimentally solved structure of a similar/homologous protein. This method builds protein structure guided by energy function.
I had prepared this presentation for an internal project during my masters degree course.
Energy minimization methods - Molecular ModelingChandni Pathak
Methods to minimize the energy of molecules during drug designing - Computational chemistry. According to the PCI syllabus, B.Pharm 8th Sem - Computer-Aided Drug Design (CADD).
Secondary Structure Prediction of proteins Vijay Hemmadi
Secondary structure prediction has been around for almost a quarter of a century. The early methods suffered from a lack of data. Predictions were performed on single sequences rather than families of homologous sequences, and there were relatively few known 3D structures from which to derive parameters. Probably the most famous early methods are those of Chou & Fasman, Garnier, Osguthorbe & Robson (GOR) and Lim. Although the authors originally claimed quite high accuracies (70-80 %), under careful examination, the methods were shown to be only between 56 and 60% accurate (see Kabsch & Sander, 1984 given below). An early problem in secondary structure prediction had been the inclusion of structures used to derive parameters in the set of structures used to assess the accuracy of the method.
Some good references on the subject:
The experimental methods used by biotechnologists to determine the structures of proteins demand sophisticated equipment and time.
A host of computational methods are developed to predict the location of secondary structure elements in proteins for complementing or creating insights into experimental results.
Chou-Fasman algorithm is an empirical algorithm developed for the prediction of protein secondary structure
Protein docking is used to check the structure, position and orientation of a protein when it interacts with small molecules like ligands. Protein receptor-ligand motifs fit together tightly, and are often referred to as a lock and key mechanism. There are both high specificity and induced fit within these interfaces with specificity increasing with rigidity. The foremost thing that we need to start with a docking search is the sequence of our protein of interest. (Halperin et al., 2002).
Protein-protein interactions occur between two proteins that are similar in size. The interface between the two molecules tends to be flatter and smoother than those in interfaces of these interactions do not have the ability to alter protein-ligand interactions. Protein-protein interactions are usually more rigid, the conformation in order to improve binding and ease movement. (Smith and Sternberg, 2002).
The process of drug development has revolved around a screening approach, as nobody knows which compound or approach could serve as a drug or therapy. Such almost blind screening approach is very time-consuming and laborious. The goal of structure-based drug design is to find chemical structures fitting in the binding pocket of the receptor. Based on the three-dimensional structure of the target protein, it can automatically build ligand molecules within the binding pocket and subsequently screen them (Weil et al., 2004).
A homology model of the housefly voltage-gated sodium channel was developed to predict the location of binding sites for the insecticides fenvalerate, a synthetic pyrethroid, and DDT, an early generation organochlorine. The model successfully addresses the state-dependent affinity of pyrethroid insecticides. (O’Reilly et al., 2006).
Ab Initio Protein Structure Prediction is a method to determine the tertiary structure of protein in the absence of experimentally solved structure of a similar/homologous protein. This method builds protein structure guided by energy function.
I had prepared this presentation for an internal project during my masters degree course.
Energy minimization methods - Molecular ModelingChandni Pathak
Methods to minimize the energy of molecules during drug designing - Computational chemistry. According to the PCI syllabus, B.Pharm 8th Sem - Computer-Aided Drug Design (CADD).
Secondary Structure Prediction of proteins Vijay Hemmadi
Secondary structure prediction has been around for almost a quarter of a century. The early methods suffered from a lack of data. Predictions were performed on single sequences rather than families of homologous sequences, and there were relatively few known 3D structures from which to derive parameters. Probably the most famous early methods are those of Chou & Fasman, Garnier, Osguthorbe & Robson (GOR) and Lim. Although the authors originally claimed quite high accuracies (70-80 %), under careful examination, the methods were shown to be only between 56 and 60% accurate (see Kabsch & Sander, 1984 given below). An early problem in secondary structure prediction had been the inclusion of structures used to derive parameters in the set of structures used to assess the accuracy of the method.
Some good references on the subject:
The experimental methods used by biotechnologists to determine the structures of proteins demand sophisticated equipment and time.
A host of computational methods are developed to predict the location of secondary structure elements in proteins for complementing or creating insights into experimental results.
Chou-Fasman algorithm is an empirical algorithm developed for the prediction of protein secondary structure
Protein docking is used to check the structure, position and orientation of a protein when it interacts with small molecules like ligands. Protein receptor-ligand motifs fit together tightly, and are often referred to as a lock and key mechanism. There are both high specificity and induced fit within these interfaces with specificity increasing with rigidity. The foremost thing that we need to start with a docking search is the sequence of our protein of interest. (Halperin et al., 2002).
Protein-protein interactions occur between two proteins that are similar in size. The interface between the two molecules tends to be flatter and smoother than those in interfaces of these interactions do not have the ability to alter protein-ligand interactions. Protein-protein interactions are usually more rigid, the conformation in order to improve binding and ease movement. (Smith and Sternberg, 2002).
The process of drug development has revolved around a screening approach, as nobody knows which compound or approach could serve as a drug or therapy. Such almost blind screening approach is very time-consuming and laborious. The goal of structure-based drug design is to find chemical structures fitting in the binding pocket of the receptor. Based on the three-dimensional structure of the target protein, it can automatically build ligand molecules within the binding pocket and subsequently screen them (Weil et al., 2004).
A homology model of the housefly voltage-gated sodium channel was developed to predict the location of binding sites for the insecticides fenvalerate, a synthetic pyrethroid, and DDT, an early generation organochlorine. The model successfully addresses the state-dependent affinity of pyrethroid insecticides. (O’Reilly et al., 2006).
Comparative Protein Structure Modeling and itsApplicationsLynellBull52
Comparative Protein Structure Modeling and its
Applications to Drug Discovery
Matthew Jacobson
1
and Andrej Sali
1,2
1
Department of Pharmaceutical Chemistry, California Institute for
Quantitative Biomedical Research, Mission Bay Genentech Hall, 600 16th Street,
University of California, San Francisco, CA 94143-2240, USA
2
Department of Biopharmaceutial Sciences, California Institute for
Quantitative Biomedical Research, Mission Bay Genentech Hall, 600 16th Street,
University of California, San Francisco, CA 94143-2240, USA
Contents
1. Introduction 259
2. Fold assignment and sequence-structure alignment 261
3. Comparative model building 261
4. Loop modeling 262
5. Sidechain modeling 263
6. Comparative modeling by MODELLER 264
7. Physics-based approaches to comparative model construction and refinement 264
8. Accuracy of comparative models 266
9. Modeling on a genomic scale 266
10. Applications of comparative modeling to drug discovery 267
10.1. Comparative models vs experimental structures in virtual screening 267
10.2. Use of comparative models to obtain novel drug leads 268
10.3. Comparative models of kinases in virtual screening 269
10.4. GPCR comparative models for drug development 270
10.5. Other uses of comparative models in drug development 271
10.6. Future directions 272
11. Conclusions 273
References 273
1. INTRODUCTION
Homology or comparative protein structure modeling constructs a three-dimensional
model of a given protein sequence based on its similarity to one or more known
structures. In this perspective, we begin by describing the comparative modeling
technique and the accuracy of the models. We then discuss the significant role that
comparative prediction plays in drug discovery. We focus on virtual ligand screening
against comparative models and illustrate the state-of-the-art by a number of specific
examples.
The genome sequencing efforts are providing us with complete genetic blueprints for
hundreds of organisms, including humans. We are now faced with describing,
ANNUAL REPORTS IN MEDICINAL CHEMISTRY, VOLUME 39 q 2004 Elsevier Inc.
ISSN: 0065-7743 DOI 10.1016/S0065-7743(04)39020-2 All rights reserved
controlling, and modifying the functions of proteins encoded by these genomes. This
task is generally facilitated by protein three-dimensional structures [1], which are best
determined by experimental methods such as X-ray crystallography and nuclear
magnetic resonance (NMR) spectroscopy. Despite significant advances in these
techniques, many protein sequences are not easily accessible to structure determination
by experiment. Over the last two years, the number of sequences in the comprehensive
public sequence databases, such as SwissProt/TrEMBL [2] and GenPept [3], increased
by a factor of 2.3 from 522,959 to 1,215,803 on 26 April 2004. In contrast, despite
structural genomics, the number of experimentally determined structures deposited in
the Protein Data Bank (PDB) increas ...
In this presentation, delve into the capabilities of MOE and discover how it enables scientists to:
Accelerate Drug Discovery: Streamline the drug discovery process with MOE's advanced molecular modeling techniques, allowing for efficient virtual screening, lead optimization, and structure-activity relationship (SAR) analysis.
Predict Molecular Properties: Leverage MOE's predictive modeling capabilities to forecast various molecular properties, including ligand-receptor interactions, protein-ligand binding affinity, and ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties.
Visualize Complex Molecular Systems: Gain deeper insights into molecular structures and dynamics through MOE's intuitive visualization tools, facilitating the interpretation of simulation results and aiding in decision-making processes.
Collaborate Effectively: Foster collaboration among interdisciplinary research teams with MOE's robust data sharing and collaborative features, enabling seamless communication and knowledge exchange.
Stay at the Forefront of Research: Keep pace with the latest advancements in molecular modeling and computational chemistry through MOE's regular updates and integration of cutting-edge algorithms and methodologies.
Orthopedics, which is a branch of clinical medicine that specializes in the diagnosis and treatment of musculoskeletal disease and trauma in the spine and extremities, owes its current status of advanced care to the development of biomaterial science more than any other clinical medical specialty
Artificial blood is an innovative concept of transfusion medicine where specifically designed compounds perform the task of transport and delivery of oxygen in the body to replace this function of allogenic human blood transfusion.
PREVALENCE OF CERTAIN DISEASES BASED ON GEOGRAPHICAL LOCATIONMelvin Alex
Infectious diseases vary by geographic region and population, and they change over time. Increasingly, humans are moving from one region to another, thereby becoming exposed to a variety of potential pathogens and also serving as part of the global dispersal process.1 Microbes picked up at one time and in one place may manifest in disease far away in time and place. Because many microbes have the capacity of persisting in the human host for months, years or even decades, the relevant time frame for study of exposures becomes a lifetime. Furthermore, microbes also move and change and reach humans via multiple channels.
Lyme disease is caused by bacterium Borrelia burgdorferi. It is transmitted to humans through the bite of infected black-legged ticks. Typical symptoms include fever, headache, fatigue, and a characteristic skin rash called erythema migrans.
The Borrelia IgM ELISA kit is an indirect enzyme immunoassay for the qualitative or quantitative determination of Borrelia IgM antibodies in human serum, plasma, and CSF samples.
Detecting neutralization antibodies to covid 19Melvin Alex
A robust serological test to detect neutralizing antibodies to SARS Cov-2 is needed to determine not only the infection rate, herd immunity, and predicted humoral protection, but also vaccine efficacy during clinical trials after large-scale vaccination.
Angelman syndrome is a genetic disorder. It causes delayed development, problems with speech and balance, intellectual disability, and sometimes, seizures. People with Angelman syndrome often smile and laugh frequently, and have happy, excitable personalities.
GenapSys™ has developed a novel electrical-based platform capable of accurately detecting single base incorporations. On the surface of the CMOS sequencing chip (Complementary Metal Oxide Semiconductor), there are millions of sensors, each designed to capture one clonally amplified bead. DNA sequencing technology.
A self-replicating machine is a type of autonomous robot that is capable of reproducing itself autonomously using raw materials found in the environment, thus exhibiting self-replication in a way analogous to that found in nature.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
5. Why?
Goal
Characterize and identify the
large number of protein
sequences that are being
discovered.
3D structure
Design of drugs, design of site-
directed mutations, to
understand how proteins
function and interact with each
other.
Experimental
structure
Developing a
structural model for a protein for
which there is no solved
experimental structure
available.
Homology
modeling
3D structure of a target protein
based on the similarity between
template and target sequences.
Predicts the 3D structure of
a protein through the sequence
alignment of template proteins.
Significance
To studying membrane
proteins that are hard to
crystallize like GPCR as it
provides a higher degree of
understanding of receptor-
ligand interaction.
14. To obtain the list of hits-the modeling
templates & corresponding alignments
COMPARES QUERY SEQUENCE TO ALL THE SEQUENCES OF KNOWN STRUCTURES IN PDB
USING TWO MATRICES: A RESIDUE EXCHANGE MATRIX, AN ALIGNMENT MATRIX.
25. References
• Insight II manual http://www.csc.fi/chem/progs/insightII.phtml.en#manual
• Structural Bioinformatics, Philip E Bourne, Helge Weissig
• Bioinformatics Sequence and Genome Analysis, David W Mount
http://ncisgi.ncifcrf.gov/~ravichas/HomMod/
http://www.biochem.vt.edu/modeling/homology.html
http://www.cmbi.kun.nl/gv/articles/text/gambling0.html
