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Compare Two Protein Sequences Using Local Blast

Hi,I have been given a task to compare the all the protein sequences of a strain of campylobacter with a strain of E.coli. I would like to do this locally using Biopython and the inbuilt Blast tools....

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data from SRA against blast databases method.

Hello.I want to find a specific gene inside SRA files and I am wondering if i am using a correct way to align those sequences because its the first time that i am "playing" with something like that.So,...

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bioinformatics related problems

hello friendsi have downloaded blast database (rpsd; for conserved domain). but i am unable to us it. so plz can anyone tell me how i can use (untar files of cdd.tar.gz file).thanks:) 

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Blast 2.25+ Segmentation Fault When -Outfmt Set To 6,7 Or 10

Hi all!I am running blast 2.25+ and willing to get output in format 7, setting -outfmt 7. However, with this setting I always get Segmentation fault. Same happens with -outfmt 6 and 10. Other settings...

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How Do You Extract The Query Title From A Blast Xml Output Using Biopython

I would like to find the alignment title along with the query title and the expect value in a BLAST XML output file with many query sequences. I can get the alignment title and expect value but the...

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How To Blast A Sequence Against Multiple Databases

Hello,I have downloaded all the chromosome of Bos taurus and I have changed them in blast format using makeblastdb..and now I want to locally blast my sequence against these all chromosomes. now I have...

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Converting Blast Output To Sam Format

Hi everybody,I was wondering if there is a blast output parser that convert blast output to SAM format. There are many blast parser out there, but most for compressing results to more readable...

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Finding an exactly conserved amino acid sequence in a particular protein.

Hi I've been trying to find a perfectly conserved region of a particular protein (secY : a membrane translocase ) among all species of Leptospira. I tried using microbial BLAST, but this isn't very...

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What'S Faster? "Blastall -P Blastp" Or "Blastp?"

I am just wondering if anyone has done a timed test and/or a memory test with blastall compared to blastp. In other words, classic BLAST vs BLAST+. It'd be really interesting to get some kind of...

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What Makes A Valid Gi List?

Hello all, I cannot figure out what makes a "correct" GI list!Atm I have a list that I produced this using the query below and a awk line to just retrieve the second column values blastn -word_size 11...

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Is A "Gene-Like," Returned By Ncbi Blast, Indicative Of Gene Family Membership?

I'm looking to sequence HSD in a non-model organism. I've been using degenerate primers for awhile and finally got a successful sequence. BUT when I enter it into BLAST, I get high sequence identity...

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Ncbi Blast Output Missing Subject Name

I'm wondering if anyone has stumbled upon this issue I'm having with blast. I have a set of contigs I'm blasting against NCBI's NR blast database, and the blast report I get back has a blank field for...

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Protein Sequence Homology Score, Align Or Blast

Hi,I want to get homology scores for every pair of human proteins acoording to their sequence amino acid constitution. should I blast these pairs(blast2seq) or align these pairs(localAlignment)?

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How To Use Biopython To Parse Blast Output And Get Gene Symbol From Ncbi?

Hello all. I am very, very new to Python/Biopython and am currently stuck.I am using standalone BLAST via Bash. I have about 40k non-human sequences which I am blasting against the human genome,...

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Affine gap penalty in Megablast

Dear all,I have a question. In megablast I don't understand why the existence and extension gap penalties in affine model are in that way. I thought the existence gap score must be always larger than...

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Scientific Notation In Blast

Hi there,I've to choose some sequences from blast result which are under 10^-5 Results are in scientific notation. How can I convert scientific notation to double? Which is the double for 2e-104 ?Thank...

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Setting E-Value In Blast

Hi,Again I realize that its an easy question :). Could anyone tell me how to set e-value to 0.005 in Blastp?

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TO BLAST LARGE QUERY SEQUENCE AT ONE TIME

hi community, i have near 4000 query sequences that i need to BLAST inorder to find homology. to do this should i need to blast my query sequence 4000 times individually one by one or we have any...

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Batch Blast Two Sequences And Output Sequence Alignment

Dear all,I want to compare a number of sequences with another list of sequences. Each comparison is consisted of only two sequences. I make an example below.FILE1>gene1_species1...

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Standalone Blast Issue

Dear all,I have recently installed blast-2.2.26 on my machine (running MacOS 10.7.3) and I tried to perform a BLAST search using a single protein sequence as query and a formatted (by me) database...

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