Bioinformatics connects life sciences and quantitative sciences, typically involving the application of software and algorithms to solve computationally intensive questions, such as those in genomics, sequence analysis, and systems biology. Questions tagged Bioinformatics should have a direct ...

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4
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2answers
135 views

Plotting metabolic networks?

I need to draw a map of the core metabolism of E.coli. Associated with each reaction in the map I have a number that indicates the flux through this reaction. I want the map to reflect these fluxes ...
7
votes
2answers
226 views

RNA-Seq library construction challenges: the biases of RNA fragmentation vs cDNA fragmentation

I recently watched a presentation on RNA-seq that covered some of the choices one can make along the way, and I didn't fully understand one of the choices in particular. Near the beginning of the ...
2
votes
2answers
55 views

Simulating Drug Entry in Protein and binding?

Is there any simulation protocol or paper which can simulate the dynamics of drug entry and interaction with the target protein?
0
votes
1answer
62 views

Nucleotide sequence for STRING protein sequence

I have protein sequences from STRING database: The amino acid sequence files are like this: 4932.Q0010 (Saccharomyces cerevisiae) ...
4
votes
2answers
54 views

where to find the relative frequency distribution of synonymous codons

Most amino acids can be encoded by more than one codon. For example, Serine can be encoded by any one of ...
3
votes
1answer
62 views

SEREX serological analysis of cDNA expression library

What is Serological Analysis of cDNA expression library? I went through this article:http://cancerimmunity.org/serex/introduction/ but could not really make out. Can someone please explain this to me ...
1
vote
1answer
641 views

What is the difference between second and third generation sequencing

I am writing the section about history of DNA sequencing in the introduction chapter and after reading quite a few research papers, I am still confused about them. Here I compile some questions to ...
1
vote
1answer
31 views

Degenerate Alignment Analysis

Can someone please tell me what is Degenerate alignment analysis? Could not find a good article on the internet that could help me understand what it means? (I have not studied biology since last 8 ...
1
vote
0answers
31 views

TAA- Tumor associated antigen [duplicate]

An approach to find Tumor associated antigens is based on transfection of expression library made from cDNA into cells expressing desired MHC haplotypes. Can someone please explain what this line ...
1
vote
1answer
24 views

Microarray probe and target

In a microarray, which one is called a target and which one is the probe? the one that is added later , is that the probe or the one present in the slots of the microarray, that is the probe? (I have ...
2
votes
1answer
122 views

Heterozygosity and the Wright-Fisher model

I was reading the textbook Probability Models for DNA Sequence Evolution by Durrett. In chapter 1, he discusses the Wright Fisher model and the coalescent theory ...
2
votes
2answers
107 views

Where to find the corrected BLOSUM matrices?

I was looking at this paper which talks about the miscalculations in the BLOSUM matrices and how the "wrong" BLOSUM62 matrix performs better than the corrected version. I was trying to find the ...
1
vote
1answer
51 views

Applying Constraint Programming to sequence alignment/analysis

My Masters program is focused on formal methods such as SAT solving and constraint programming. I am interested in applying such techniques to problems in sequence alignment and sequence analysis, ...
2
votes
0answers
32 views

Genome-wide methylation analysis: sources of technical error?

We are doing a genome-wide analysis of methylation via bisulfite sequencing for an insect species. Previous experimental techniques have suggested the presence of methylation in this organism, ...
1
vote
1answer
60 views

Modelling how much cadmium a cell will be able to chelate with phytochelatins

I am involved in a synthetic biology project where I have to do modelling with ODEs. The biological process I want to model is the chelation of Cd2+ with phytochelatins, to know how much can be ...
0
votes
5answers
158 views

How much does a typical biologist know about signal processing, machine learning, and (theoretical) computer science? [closed]

How much does a typical biologist know about signal processing, machine learning, and (theoretical) computer science? Coming from a neuroscience background where knowing about algorithms and computer ...
3
votes
0answers
41 views

What does the term 'epitope mapping' mean? [closed]

Epitope mapping means identifying the binding site of antibodies on the target antigen. This means that the site to be identified is part of the antigen and not antibody, am I right?
2
votes
2answers
120 views

How do I perform recurring pattern mining or regular expressions of nucleotide sequences?

I am interested in performing nucleotide sequence pattern-mining (regular expressions) which is 12 characters (sequences) in length from a dataset. Is that possible to script using MATLAB?
4
votes
2answers
144 views

positive and negative feedback

I want to know more about positive feedback in gene regulation and to know the similarity and differences between positive and negative feedbacks.
2
votes
1answer
300 views

Using RNA-seq to compare gene expression across patients instead of between Control and Experimental conditions

I am working with RNA-seq data from the Cancer Genome Atlas TCGA and I have been reading about how people have compared gene expression levels measured by RNA-seq. Many of the papers I have read talk ...
15
votes
4answers
359 views

Machine learning for light microscopy — problems to solve?

I would like solve some biological problems that would improve the state-of-the-art of biology or bioinformatics. In particular, I want to apply machine learning on light microscopic images. The ...
1
vote
1answer
113 views

Datasets of aligned nucleotide sequences [closed]

Where can I find some datasets of aligned nucleotide sequences? And what should I assume about the accuracy of the alignments there? (I would like to use such datasets for training the alignment ...
1
vote
1answer
53 views

How to selectively download 3 fields from every record in UniProtKB?

I want to download a comprehensive table of protein names from uniprot.org. More precisely, I want to generate a tab-delimited table consisting of the id ...
2
votes
0answers
24 views

How are HSPs identified in UCLUST

I am new in Bioinformatics and recently studying UCLUST algorithm by Robert Edgar(2010). It is a fast sequence searching and clustering algorithm. The algorithm is heuristic based. I studied that ...
4
votes
2answers
459 views

Why is assembling paired end illumina without any input parameters an important problem?

In one of the comments in this question about multiple sequence alignment, it was stated @5heikki: btw if you want a good bioinformatics problem, come up with an assembler that assembles any ...
4
votes
2answers
172 views

What is the state-of-the-art algorithm for multiple sequence alignment?

Which algorithm or algorithms are considered the standard or state-of-the-art for multiple sequence alignment? How big is the need for better algorithms? How many sequences need to be alignment in a ...
1
vote
2answers
88 views

Recommended sequence clustering algorithm for transcriptome data

I'm working on a project where I'm going to analyze a large amount of transcriptome data. After assembling our RNA-Seq reads into contigs using Trinity, it looks like I'm going to have about 10GB of ...
2
votes
2answers
389 views

MOL2 to PDBQT conversion via OpenBabel and MGLTools removes hydrogen atoms

I am trying to convert a MOL2 file (includes partial charges and hydrogen atoms) into a PDBQT file for re-scoring in AutoDock Vina. However, both approaches that I tried don't keep the hydrogen atoms ...
3
votes
2answers
278 views

How to use Autodock just for (re)scoring

I have some protein-ligand complexed that I have been docking with some other software and just want to use Autodock to evaluate those complexes. So, basically I just want to use it as a scoring ...
1
vote
1answer
66 views

To what extent is it possible to understand if a bacteria can produce a protein? (in silico only!)

I have to answer a question about a sub-task of my thesis: Can the bacteria X produce the protein Y? I searched of course Google and BLAST. There is no data supporting that this specific bacteria ...
3
votes
0answers
140 views

Accuracy of genome size estimation by flow cytometry

I'm working on a genome project and using an in silico k-mer analysis to estimate the size of our genome based on the available Illumina reads. The k-mer based estimate is consistent across a wide ...
1
vote
1answer
233 views

Convert gene name to uniprot ID

i have a list of gene name in a file CHRNB2 EGR2 GCK KRT14 LMNA FGF3 TK2 ABCC8 How can I map them to uniprot ID ? P.S I tried Uniprot "ID mapping" ...
1
vote
2answers
121 views

Heterochromatin binding sites position information

I am working on a project and I'm trying to find data on the position of genes and heterochromatin binding sites such as HP1 in Drosophila melanogaster. Is this information available for the DGRP ...
2
votes
2answers
52 views

Hiding identical sequences in NCBI web interface

Sometimes there are identical sequences in Genbank/Genpept, most often coming from the same species but different strains. Ie if I look up "bacteria chitin synthase", the 624-aa protein from Dickeya ...
2
votes
0answers
56 views

Can a heterozygous allele show non-heterozygous expression in a family?

I'm doing a family study looking for novel cancer-associated variants in germ-line samples; the goal is to find candidate biomarkers which might be used for early detection. At an earlier step our ...
4
votes
4answers
3k views

E-value BLAST cut-off

What is the best cut-off for e-value in BLAST? Some say 0.01 ,others 0.0001? Even BLAST tutorials don't give a very clear idea about which cutoff suits which purpose? Could some experts give me a ...
2
votes
0answers
177 views

Software to calculate Fst from sequence data

I'm looking for a software to calculate Fst from 3 loci DNA data of individuals from a metapopulation. I don't have any prior on the population structure (have no idea of the number of subpopulations ...
2
votes
1answer
44 views

Quantitative Comparisons of Phylogenetic trees

I am working on a broad phylogenomic analysis of proteins involved in one particular cellular process. I have constructed a phylogenetic tree for each protein. I am now working on comparing those ...
4
votes
1answer
123 views

Blosum matrix with probabilities instead of the positive and negative scores

I am trying to find a version of the BLOSUM matrix that has the frequencies instead of the scaled log-odds. i.e. instead of the common version that tells us that the score LEU/ASP is -4, I would like ...
3
votes
1answer
110 views

Should the sum of RPKMs be constant over experiments

I have cufflinks data from 18 different RNA-seq experiments. I've noticed that if the sum all the RPKM values for a particular experiment, are vastly different between experiments. How could this be? ...
2
votes
0answers
40 views

dbSNP database table desciptions

I am trying to build a local implementation of dbSNP. I would like to know the descriptions of tables listed on ftp://ftp.ncbi.nlm.nih.gov/snp/database/organism_data/human_9606 and on ...
4
votes
1answer
190 views

Local storage of NCBI database in MongoDB [closed]

My short term goal in a project is to build a local database of the NCBI dbSNP database. The data and schema are available on the FTP site(). I was going to implement the database using MySQL, but I ...
3
votes
1answer
70 views

Regarding the NCBI FTP site

I am trying to extract information about SNP data from the FTP server of NCBI. Could someone please explain to me how the directory is organised? There are many many files and folders and I can't ...
5
votes
3answers
222 views

Protein structures given in PDB and SNP's

There are millions of proteins given in PDB, the sequence for which we can download in FASTA format. There are also hundreds of SNP's given in NCBI dbSNP. My question is whether the proteins in PDB ...
3
votes
1answer
48 views

I2D vs STRING for protein-protein interactions

Can someone clearly explain me the differences between STRING and I2D(Interlogous interaction database) ? What does each database do best ? Which database is better for what kinds of studies etc ?
1
vote
1answer
45 views

Alleles notation in SNPPedia criteria

I can understand the allele notation when is in the form rs8176719(T;T) or rs8176719(G) but recently i found this ones rs8176719(T;-) or rs8176719(-;T). So im confused, rs8176719(T;-) is the same as ...
3
votes
1answer
224 views

What do the Clustal Alignment Symbols Mean?

Occasionally I will run protein alignments on peptide families and I can never remember what the symbols mean to show degrees of identity. What do they mean?
1
vote
1answer
29 views

Why are different lengths of nucleotides taken for structure prediction from an miRNA match area after BLAST analysis?

Generally in miRNA prediction most researchers do as Blast search with a set of miRNAs downloaded from miRBase with the parameters they require. Later on usually custom methods are utilized to get an ...
1
vote
1answer
67 views

downloading a reference genome for alignment

I am currently working through the code example on the MATLAB website. It requires me to download the reference genome of Arabidopsis thaliana (thale cress) so I can use BowTie2 to align the Chip-Seq ...
5
votes
5answers
165 views

What are some examples of evolving networks in biology?

I'm a master student working on networks analysis in general. A network is something that has nodes and there are links between the nodes. Nodes and links could have attributes. An evolving network is ...