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Error in fetching the Refseq using Taxonomic ID

I have been trying to extract the reference sequences for the list of taxonomic IDs I have like:

Taxon ID
1438843
1421962
1324283
1422107

So, for 1438843, the reference sequence is NC_000962.3 and I need to download this particular reference sequence with respect to taxonomic ID 1438843.

When I try to fetch the RefSeq for the first taxonomic ID using the following Eutility command:

esearch -db genome -query "txid1438843 [Organism]" | elink -target nuccore | efilter -query "refseq"| efetch -format fasta

It shows an error like:

ERROR in filt input: callMLink: Query failed on MegaLink server

ERROR in fetch input: callMLink: Query failed on MegaLink server

Could any suggest me a way to fetch the refseq for the above mentioned taxonomic IDs?

eutility ncbi reference sequence
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updated by Nelo • Nelo • written by Paul Paul

Hello Good evening

How to extract protein Id from the given gene ID

gene ID: AB845604 AB845605 AB845606 AB845607 AB845608 AB845609 AB845610

Tnks in advance

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written by Nelo • Nelo

It is not a good practice to ask unrelated questions in pre-existing threads.

You can do the following with EntrezDirect:

$ esearch -db gene -query "AB845604" | elink -target protein | efetch -format acc
NP_001289835.2
BAO18621.1

Use a for loop to go through your list.

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written by GenoMax GenoMax

opps My mistake not very much familiar with this, but will keep in mind next time Actually i got the same isses like this:

" ERROR in filt input: callMLink: Query failed on MegaLink server "

while i was trying out some commands to convert to the protein ID.

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written by Nelo • Nelo

1 answer

I was able to download the sequences by removing the space between txid1438843 and [Organism]

esearch -db genome -query "txid1438843[Organism]" | elink -target nuccore | efilter -query "refseq"|efetch -format fasta
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written by Sej Modha Sej Modha

Thanks it's not showing error anymore. But results in multiple sequences, whereas I need only one RefSeq sequence (NC_000962.3)

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written by Paul Paul

I am going to hazard a guess that since you are using a taxID (for Mycobacterium tuberculosis) every M. tuberculosis genome that is there in RefSeq database (currently 5248) is going to be pulled up. You probably need an additional filter on your query.

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written by GenoMax GenoMax

That's right, you will need another filter that fetches the representative assembly. Following command returns fasta sequence for NC_000962.3. 

esearch -db genome -query "txid1438843[Organism]"|elink -target assembly|efilter -query "representative[PROP]"|elink -target nuccore -name assembly_nuccore_refseq|efetch -format fasta
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written by Sej Modha Sej Modha

Nice! Looks like you know your entrez utilities by heart.

Slightly unrelated question. Is there a chart representation of what can/should be logically connected with what for various entrez utilities? I find the in-line help severely lacking except for providing bare syntax.

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written by GenoMax GenoMax

Thanks :) it worked like a charm

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written by Paul Paul

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