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AlphaFold is a deep learning model developed by the DeepMind team at Google for predicting the three-dimensional structure of proteins. In case, you are new to AlphaFold,  here  is a quick introduction to the program. AlphaFold uses a neural network to predict the three-dimensional structure of a protein from its amino acid sequence. The neural network is trained on a large dataset of known protein structures and amino acid sequences, using a technique called supervised learning. The model uses a combination of convolutional neural networks (CNNs) and recurrent neural networks (RNNs) to learn the complex relationships between protein sequences and structures. The output of the AlphaFold model is a prediction of the three-dimensional structure of the protein, represented as a set of coordinates for each atom in the protein. These predictions are evaluated using a range of metrics, including the predicted local distance difference test (PLDDT), predicted torsion angle metri...

PyMOL is a powerful molecular visualization software that also allows users to edit molecular structures. Here are some ways to edit structures with PyMOL: If you are new to Pymol, I would recommend practicing  here . I can also recommend you slightly expert-level tutorial  here . 1. Add Atoms and Residues: To add atoms or residues to a structure, use the "Builder" function. First, select the residue or atom you want to add to. Then, go to "Wizard" > "Builder" and choose the atom or residue to add. 2. Delete Atoms and Residues: To delete atoms or residues from a structure, use the "Delete" function. First, select the atoms or residues you want to delete. Then, go to "Actions" > "Delete" and confirm the deletion. 3. Mutate Residues: To mutate a residue to another amino acid, use the "Mutagenesis" function. First, select the residue you want to mutate. Then, go to "Wizard" > "Mutagenesis...

Pymol is a powerful and versatile molecular visualization software that allows users to create high-quality 3D representations of molecular structures. Here are some specialized tricky and magical codes of Pymol. If you are new to Pymol, it is highly advised to practice  Basic Pymol Tutorial . In case you are looking to learn structure editing in Pymol, please follow  here . 1. Tricks Displaying secondary structure The following code displays the secondary structure of a protein using a color code where alpha helices are red and beta sheets are yellow. show cartoon set cartoon_ring_mode, 3 set cartoon_ladder_mode, 1 set cartoon_fancy_helices, 1 color red, ss h color yellow, ss s 2. Aligning structures The following code aligns two structures based on their alpha carbons and displays the aligned structures in different colors. align 1abc and chain A, 2xyz and chain B color blue, 1abc color green, 2xyz 3. Creating a surface representation The following code creates a surface rep...

PyMol is an important package for analyzing and generating publication-quality or high-quality images. After reading this tutorial, you will be able to generate simple ribbon diagrams with labels if required. Generating specific surface representation to your system and the last section is all about how to generate high-quality figures of protein and ligands. The current document is a basic tutorial and those who are already familiar with Pymol are advised to follow  here.   Before going to the following sections, you are required to load your PDB file, and change your display color to the one intended. Display --- Background How to read the below part, if you are new? A sentence that starts with "#" is just an explanation of the code present in the very next line. Pymol offers you two parts in the GUI interface, and you can use the below codes in any interface. 1. Tutorial on generating a ribbon diagram and adding labels: # Load a protein structure load protein_name.pdb # Sh...

There are several bioinformatics tools that can be used to prepare a dataset of homologous protein sequences. Here are some commonly used tools:  Basic steps while using the below tools. BLAST: Basic Local Alignment Search Tool (BLAST) is a widely used sequence similarity search tool that can be used to find homologous sequences in a database. It can be run locally or online through the NCBI BLAST website. HMMER: HMMER is a software suite for protein sequence analysis that can be used to search sequence databases for homologous proteins using hidden Markov models (HMMs). It can be used to detect remote homologues that may not be detected by BLAST. CD-HIT: CD-HIT is a clustering tool that can be used to reduce redundancy in a set of homologous sequences. It clusters similar sequences together and removes redundant sequences based on a user-defined sequence identity threshold. MUSCLE: MUSCLE is a multiple-sequence alignment tool that can be used to align a set of homologous sequen...

Preparing a list of homologues involves identifying and collecting protein sequences that are evolutionarily related and share a common ancestor. Here are some general steps that can be followed to prepare a list of homologues: Determine the protein of interest: Identify the protein of interest for which you want to find homologues. This protein should be well-characterized and have a known function.  Tools to Generate Homologues Dataset Perform a sequence search: Use a sequence search tool, such as BLAST or PSI-BLAST, to search for sequences that are similar to the protein of interest. These tools compare the protein sequence against a database of known protein sequences and return a list of hits that have significant sequence similarity. Filter the hits: The sequence search may return a large number of hits, many of which may be irrelevant or redundant. To filter the hits, you can set a threshold for sequence similarities, such as a minimum percentage identity or a minimum e-va...

When you have to perform molecular docking, the selection of an appropriate scoring function becomes necessary and that depends on the specific research question and the availability of computational resources. Both empirical and physics-based scoring functions have their own strengths and weaknesses, and the choice of the scoring function will depend on the accuracy and speed required for the particular research question.  What are scoring functions? Empirical scoring functions are faster and less computationally expensive than physics-based scoring functions. They are based on a statistical analysis of known protein-ligand complexes and use a set of parameters to describe the interactions between the protein and the ligand. Empirical scoring functions have been shown to accurately predict the binding affinities of a wide range of ligands to diverse proteins. Physics-based scoring functions, on the other hand, are based on physical principles such as force fields and quantum mecha...

Molecular docking is a computational method used to predict the binding mode and affinity of a ligand to a protein or other molecular target. One of the key components of molecular docking is the scoring function, which is used to evaluate the binding affinity between the protein and the ligand. In this blog post, we will discuss the different types of scoring functions used in molecular docking programs.  Scoring functions are mathematical algorithms that evaluate the interactions between the protein and the ligand and calculate a score that reflects the binding affinity. The score is used to rank different ligands and predict their binding affinity to the protein. The most commonly used scoring functions can be divided into two categories: empirical and physics-based scoring functions. Empirical scoring functions are based on a statistical analysis of known protein-ligand complexes. These functions use a set of parameters that describe the interactions between the protein and th...

In the field of bioinformatics, sequence alignment is a fundamental task for comparing and analyzing nucleotide or protein sequences. One of the key measures used in sequence alignment is the Hamming distance and Levenshtein distance, which are used to quantify the difference between two sequences. In this blog, we will discuss how Hamming and Levenshtein distances are used in the sequence alignment and their applications. Hamming Distance in Sequence Alignment: Hamming distance is used in the sequence alignment to measure the difference between two sequences of equal length. It is defined as the number of positions at which the corresponding symbols in the two sequences are different. For example, the Hamming distance between the DNA sequences "ATGCTAG" and "AGGCTAG" is 1, because the second symbol is different in the two sequences. In sequence alignment, Hamming distance is used to identify conserved regions in multiple sequence alignments. Conserved regions are r...

 BioEdit is a popular freeware biological sequence alignment editor and analysis program that is widely used in the field of molecular biology. It allows users to create, edit, and analyze nucleotide and protein sequences. This tutorial will provide a step-by-step guide on how to use BioEdit for sequence alignment and analysis. BioEdit software is a useful utility in  Sequence Alignment and Research Installation and Launching: The first step is to download the BioEdit program from the official website and install it on your computer. Install BioEdit  After installation, launch the program by clicking on the BioEdit icon on your desktop. Sequence Import: Once the program is launched, the next step is to import your sequence data into BioEdit. You can do this by selecting “File” from the menu bar and then choosing “Open” from the dropdown list. This will bring up a file dialog box, where you can navigate to the folder where your sequence files are stored and select the file...

Scholarship interviews are an important opportunity for candidates to demonstrate their strengths and convince the selection committee that they are the best candidate for the scholarship. Professors are often part of the selection committee and may ask questions to assess the candidate's academic and personal qualities. In this blog, we will explore some possible questions that professors may ask in scholarship interviews. Can you tell us about your academic achievements? This is a common question that allows candidate to highlight their academic successes. It is an opportunity to showcase grades, academic awards, and other relevant achievements. The candidate should be concise and specific in their answer and emphasize how their academic accomplishments align with the scholarship's goals. How will this scholarship help you achieve your goals? This question is an opportunity for the candidate to articulate how the scholarship aligns with their personal and academic goals. The ...

Every year, the Chinese Government attracts students across the globe through Chinese Government Scholarships for Master's and Ph.D. programs offered in all disciplines. In this blog, I will tell you how to apply or how to make your chances brighter for selection. So before going to start, let me tell you that avoid following agents, there is no need for agents, you can achieve it better by yourself. Step 1: You need to decide whether you want to avail of a scholarship or want it in high ranked University or institution? In any case, you are suggested to do a google search and pick a list of Chinese Universities, high-rank universities. To can also find that list here  Chinese Universities Ranking 2023 Step 2: According to your answer in step 1, if you are interested in a scholarship then I would suggest you select a University that falls below Rank # 50, which will maximize your chances of selection as most of the traffic is toward high-rank Universities. Now a question may come...

Common sense is a term that we hear frequently, but what does it actually mean? At its most basic level, common sense can be defined as the ability to use sound judgment in practical situations. It is the ability to make reasonable and practical decisions based on one's own experiences, observations, and knowledge of the world. Common sense is a fundamental aspect of human intelligence and is present in individuals from all walks of life. It is the ability to make practical decisions based on a general understanding of the world and the context in which one finds themselves. Common sense is not necessarily based on specialized knowledge or training, but rather on the ability to think critically and logically about a situation. The term "common sense" is often used in contrast to specialized knowledge or academic expertise. While expertise in a particular field is important, common sense is a more general form of intelligence that is relevant to all aspects of life. Common...

When we close our eyes, we often experience a range of visual phenomena, from simple colors and patterns to more complex images and even hallucinations. These visual experiences can be both intriguing and mysterious and have captured the attention of scientists and philosophers for centuries. So, what do we see when our eyes are closed? The answer to this question is not straightforward, as the visual experiences that we have when our eyes are closed can be influenced by a number of factors, including our state of mind, our level of sensory deprivation, and our individual brain chemistry. One of the most common visual experiences that we have when our eyes are closed is the appearance of simple colors and patterns. These visual phenomena are known as phosphenes, and they occur as a result of the stimulation of the retina by pressure or electrical currents. When we close our eyes, the pressure on the retina changes, which can trigger the perception of colors and patterns. These phosphen...

The age-old question of whether the chicken or the egg came first has puzzled philosophers, scientists, and curious individuals for centuries. While this may seem like a straightforward question, the answer is not as clear-cut as one might think. From a biological perspective, both the chicken and the egg are essential for the continuation of the species. The egg provides a protective environment in which the developing embryo can grow and develop, while the chicken provides the genetic material necessary to create the egg. In order to understand which came first, we must first understand the process of egg formation. Female chickens, known as hens, have a specialized reproductive system that enables them to lay eggs. The process begins with the production of egg yolk in the hen's ovary. The yolk then moves into the oviduct, where it is fertilized by a sperm from the rooster. The fertilized egg then travels through the oviduct, where it is covered with layers of albumen (egg white)...

 Amino acids are the building blocks of proteins, which are essential for the growth, repair, and maintenance of animal bodies. Animals obtain amino acids from the food they eat, and their bodies use various mechanisms to absorb and process them. In this blog, we will explore how animal bodies gather amino acids from their diet. Digestion: The first step in the process of gathering amino acids is digestion. Proteins in the food are broken down into their constituent amino acids by digestive enzymes in the stomach and small intestine. These enzymes break the peptide bonds that link amino acids together, releasing individual amino acids into the bloodstream. Absorption: Once the amino acids are released from the protein molecules, they are transported across the wall of the small intestine into the bloodstream. This process is facilitated by specific transporters that recognize and bind to individual amino acids. The amino acids are then carried in the bloodstream to various parts of...

Currently, there is no way to predict earthquakes with certainty. However, there are certain indicators that can provide some level of insight into the likelihood of an earthquake occurring in a certain area. Scientists use a combination of seismic, geological, and geodetic data to identify areas of increased seismic activity and to estimate the likelihood of future earthquakes. Seismologists use seismographs to measure the ground movements associated with earthquakes, and they can use this information to identify areas where the earth's crust is under stress and is likely to produce an earthquake. They also use geological information to understand the history of earthquakes in a particular area and to identify areas where the fault lines and tectonic plates are most likely to move.  Geodetic techniques, such as GPS and InSAR, can also provide important information about changes in the earth's surface that may indicate increased seismic activity. Despite these advances, the abi...

Earthquakes are a natural phenomenon that has been shaking our planet for millions of years. They are caused by the movement of tectonic plates, the buildup of stress in the Earth's crust, and volcanic activity. Earthquakes release energy stored in the Earth's lithosphere, which is the outermost layer of the solid Earth that includes the crust and the uppermost part of the mantle. This energy can result in ground shaking and even cause damage to buildings and infrastructure. However, earthquakes are not just destructive forces. They also provide important information about the inner workings of our planet. By studying earthquakes, scientists can learn about the composition and structure of the Earth's lithosphere, as well as its tectonic processes. Earthquakes are one of the ways in which the solid Earth responds to the changing forces acting upon it, including the motion of tectonic plates, the buildup of stress in the Earth's crust, and volcanic activity. Earthquakes ...

Sequence alignment is a fundamental technique in bioinformatics that is used to compare and match the sequences of biological molecules, such as DNA, RNA, and proteins. The main goal of sequence alignment is to identify similarities and differences between sequences and to determine the evolutionary relationships between them. Types of Sequence Alignment There are two main types of sequence alignment: global alignment and local alignment. Global alignment involves aligning the entire length of two sequences, while local alignment focuses on aligning only the conserved regions between two sequences. Global alignment is used to determine the overall evolutionary relationship between two sequences. This type of alignment is used to construct evolutionary trees that show the relationships between different species. The most widely used global alignment method is the Needleman-Wunsch algorithm, which uses dynamic programming to align two sequences. Local alignment , on the other hand, is u...

In protein science research, researchers are always looking to predict the structures with better accuracy. There are several metrics available, that can tell the overall nature of the model quality. One of them is the Template Modeling score or normally called TM score. Programs like I-TASSER will provide this score but unfortunately, majority of the normal users skip it. So, here I am going to tell you that what it TM and which TM score can be considered a better one.  Remember this score will always be in the range of 0-1, and for your ease 0.2 means 20% and vice versa. If you are using AlphaFold for structure modeling, I would recommend here  understanding the metrics of AlphaFold for a quality of protein structures. Template modeling score is an important metric used to assess the quality of protein structure predictions generated by template-based modeling methods such as homology modeling and comparative modeling. The score is a measure of the similarity between the pr...