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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How could I identify whether given RNA-seq data is paired end or single end

I need to have a RNA-Seq dataset and therefore, I've visited the following site NCBI-geo C. Elegans In the Supplemantary file part, I clicked the SRP/SRP051/SRP051702 ftp and downloaded sra file. ...
4
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1answer
147 views

Epistasis Across Chromosomes and Individuals 'Homozygous for Interactions'

Apologies for any failures in nomenclature. I'm a mathematician who is making a foray into genetics for a masters thesis. Specifically, I'm generating artificial diploid genetic sequence data and ...
4
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2answers
249 views

Relative microRNA comparison from from TCGA data?

I have a conceptual question that I was hoping someone could answer. Can I say that microRNA A is expressed x-fold greater than microRNA B directly from the TCGA miRseq data? Can I do this after ...
4
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1answer
137 views

Is it possible to dock multiple ligands with the target?

Is it possible to dock multiple ligands with a target? If so, what is the suitable software used for? -- Is it possible to fix specific docking region for the target (or) automatic?
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102 views

Publicly available resources for learning metagenomics

We are starting a metagenomics project in our research group to study microbiota in the respiratory tract. Since the are no books yet about metagenomics, seems reading some reviews and online ...
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194 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 ...
4
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1answer
67 views

relative-rate of evolution

I am supposed to calculate the relative rate of evolution of two sequences (human and sheep) with a chicken serving as the outgroup. The sequences are pretty long, so I will just create a short ...
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2answers
124 views

Reference sequence for defining single nucleotide polymorphisms

Single nucleotide polymorphism (SNP) or genetic variation in general, by definition are relative to a reference sequence. When we talk about databases of SNP as in ("dbSNP—Database for Single ...
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59 views

Finding RNA Loops

I was rooting through the literature, but there is too much work on the topic of detecting loops in RNA and the RNA helices that go with them. Can anyone point to a good review on this topic or even ...
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246 views

What makes a DNA sequence motif a DNA sequence motif?

I've read about DNA sequence motifs, but still don't understand what makes some sequence a DNA sequence motif. Is this a well-defined concept? For, example, What are DNA sequence motifs? says: ...
4
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2answers
103 views

Combining gene expression data from two species

I currently have two sets of gene expression data. The first is a dataframe of genes identified by Annotation id CG numbers (for example "CG10005") in one column and a numerical variable of interest ...
4
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1answer
102 views

Assembly of metagenomic data

I'm trying to assemble metagenomic data that comes from termite guts. The sequences comes from SOLiD and no paired, so the reads are extremely short (25bp). I have tried multiple assemblers (CLC, ...
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2answers
64 views

Where can I find histograms and tables of prevalence of mutations in cancer?

At some point in the past I found a cancer portal site which had aggregated data for the relationships between various mutations and their prevalence in cancer types and tumor data. The data was ...
4
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119 views

Online toolkit that provides functional similarity scores (in the form of a matrix) between two functional gene sets in the context of gene ontology

Where can I find an online toolkit that provides functional similarity scores (in the form of a matrix) between two functional gene sets in the context of gene ontology? I have tried the following: ...
4
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1answer
60 views

What value type would a chromosome position be in a database or form?

I wanted to create a tool for some fields like SIFT, Phenotype, etc..so for example I know Phenotype will have "Text" values or SIFT will have some determined values from a drop down list...but what ...
4
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1answer
72 views

Statistics on energy consumption breakdown per biological functions across organisms?

Are there any statistics available on how much energy organisms use for each biological functions (i.e. something similar to the line of "Bacteria spend X% of energy on information processing, Y% for ...
4
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1answer
963 views

How do I view the simulated protein structure along with ligand in VMD?

I did a simulation of a protein-ligand complex, and it has stabilized after 5 ns. I have got the respective pdb files for every ns, but when I try to view in VMD (Visual Molecular Dynamics), I cannot ...
4
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1answer
54 views

How to find ion/water channel related genes

We now have a collection of transcripts at hand. We would like to investigate some particular ones, which are ion/water channel related. How to perform this? Could anybody point out how to find the ...
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49 views

Which sequence assemblers I can use to compare different paradigms?

I'm a high school student whose interested in bioinformatics. Therefore I chose a project which I study Sequence Assembly. My main goal is to compare different paradigms (Greedy, OLC, De Bruijn). I ...
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99 views

Are there any de-novo genome assembly programs for HADOOP?

I have access to a small (approx 20 nodes) cluster that has HADOOP running on it, and I need to do some de-novo genome assembly. I'd like to ask is anyone knows of any program that can do this on a ...
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285 views

Statistical Coupling Analysis (SCA) to identify coevolved residues: use of ICA [closed]

We've begun to try out the SCA Matlab toolbox (latest version) downloaded from Dr. Rama Ranganathan's website, and, following the included tutorials, would like to apply it to our protein family. The ...
4
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2answers
210 views

Biological key file format

I am in the process of creating biological key software tool for use on android devices. I would like to know if there are any established file formats for storing biological key data. Thanks
4
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0answers
156 views

Organize sequence database [closed]

I recently took up the task of organizing the sequencing database for a research project. I am still quite unsure of which database type I should use for this. Some advices/recommendations would be ...
3
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2answers
196 views

High sequence similarity but start codon isn't methionine

I have noticed in a particular genome sequence of a prokaryote that various regions in a sequence share similarity which is high(>80%) with known proteins. However, the start is not a methionine. Is ...
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3answers
528 views

Bioinformatics tool for “pairwise alignment” of complementary sequences?

I'm currently working on some ribozyme binding, and I'm looking for a tool that will essentially analyze the regions of the degree of complementarity in two sequences in order to extrapolate ...
3
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1answer
99 views

What is the last heavy atom of an amino acid?

I'm a electrical engineer and I'm learning about bioinformatics. I was reading this paper that uses the last heavy atom to search for active sites of a protein but what would be a heavy atom? Is it ...
3
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1answer
91 views

What information can Uniprot give me about phosphorylated forms of proteins?

I have a list of proteins formatted like this: ...
3
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1answer
665 views

Ka/Ks (dN/dS) analysis module for Python?

From this wiki article: In genetics, the Ka/Ks ratio (or ω, dN/dS), is the ratio of the number of Nonsynonymous substitutions per non-synonymous site (Ka) to the number of synonymous ...
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2answers
456 views

JMol “calculate HBONDS”: which atom is the donor/acceptor?

JMol can be used to identify Hydrogen bonds in proteins by the script "calculate HBONDS". By outputting the state of the network, we can obtain a lisdt of H-bonds. Here's one line from an example ...
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2answers
120 views

Is there a database of cell images?

We're working on an algorithm for processing images of cells, similar to but much more basic than Cell Profiler, and we are looking for a large database of cell images to test our software. Can anyone ...
3
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2answers
83 views

Microbiome Data

How is it possible to access microbiome data like that found here? I'd like to perform analyses on similar type of data, but cannot find OTU data like that at the Human Biome Project. Thanks for any ...
3
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1answer
89 views

How to perform a DNA structural alignment in pymol

How can I "fit" two DNA structures having different nucleotide sequences in pymol? I would like to use the structure of a DNA binding protein in pdb (1h9t), which is bound to DNA in the pdb file, ...
3
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2answers
90 views

Construct Phylogeny form Edgelist

I am working on large scale biodiversity simulations and have collected a lot of data on simulated phylogenies. I have a list of child-parent edgelist species in the form: ...
3
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2answers
80 views

Sequence compression method / format

As someone working with sequencing data and sequence files I was wondering whether is there a compression method / format for sequence / read files? Of course one can use general compressors like rar ...
3
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1answer
234 views

meaning of the “reads” keyword in terms of RNA-seq or next generation sequencing

I'm an undergraduate student at computer science and currently, I'm interested in bioinformatics. Today, I've started to read a paper about clustering and classification of non-coding RNAs can be ...
3
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1answer
414 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?
3
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1answer
53 views

Number of autoregulation and FFL motifs in a network

Suppose we have a network with N* nodes (N* is the number of internal nodes). Every directed link in this network exists with probability p. What would be the number of: motifs that are ...
3
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1answer
196 views

Any tool to align whole genome sequence data to another genome and give exon regions a higher mark?

I want to align WGS data from several mammals to one reference such as the human genome sequence. Since in most cases exons should be conserved and spliced in the same way and introns should vary, I ...
3
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1answer
1k views

Difference between “transcriptional activity” and “RNA expression”

I am working with a network object where the nodes are different events in molecular biology. Specifically; Catalytic activity of X, RNA expression of X, GTP-bound activity of X, Kinase activity of ...
3
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1answer
85 views

Why perform imputation?

Genetics datasets contain measurements for millions of single nucleotide polymorphisms (SNPs). Some (usually small) percentage of these values are of low confidence, and are labeled as missing values. ...
3
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1answer
37 views

Which hydrophobicity scales are best for detecting transmembrane regions, and why?

There are many hydrophobicity scales for protein analysis. Broadly, I gather the differences between them are from the experimental method to acquire the data and the normalisation (or lack thereof) ...
3
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4answers
346 views

Identifying the origin of replication of an unannotated *E. coli* plasmid

I have attempted a few searches for a list of origins of replication for plasmids in E. coli, but I was only able to find a list of origins, but not their individual sequences. The available plasmid ...
3
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1answer
1k views

Hamming distance between two DNA strings

By definition from Wikipedia, the Hamming distance between two strings of equal length is the number of positions at which the corresponding symbols are different. In other words, it is the number of ...
3
votes
1answer
96 views

PSI-BLAST website algorithm parameters

http://blast.ncbi.nlm.nih.gov/Blast.cgi In this website, when I want to apply the psi-blast algorithm on a sequence, under the section of algorithm parameters , what does PSI-BLAST threshold mean? ...
3
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2answers
418 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 ...
3
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1answer
150 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? ...
3
votes
1answer
2k views

RNA-seq analysis - q-values in cuffdiff

I'm using cuffdiff 2.1.1 to look for differential gene expression between two conditions. Each condition has 2 biological replicates. The results I get look promising from a log fold change ...
3
votes
1answer
164 views

Can compounds be predicted from Polyketide synthases gene clusters?

I've seen a few talks on the subject. From a gene cluster, there is some decent ability to determine which domains contribute to certain functional groups in the final metabolites. It sounds like this ...
3
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1answer
633 views

Displaying nucleotide at a single position from RNA-seq reads in a BAM file

How do I display a single nucleotide position from reads in a BAM file? I have been looking at variation using samtools mpileup, but I want to actually just display the nucleotide at the position I am ...
3
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1answer
51 views

How to predict a mRNA secondary structure with a large sequence?

When I use some web servers to predict a mRNA secondary structure, I find they always required in a small size sequence. If I use a long sequence and cut it into small parts, do these small parts ...