Non-Human Genomes
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Using the ORF Finder to find a gene in a prokaryotic DNA sequence

  Sample User Question
Step By Step Guide
 

Sample User Question back to top

Is there a defined gene in the following region (70000-72500 bp) of DNA sequence from the Haemophilus influenzae?

Step By Step Guide back to top

Yes! Using the ORF Finder, you will discover that this region contains the coding Sequence for the MutL gene, which is involved in DNA mis-match repair. To see this, do the following:

  1. Cut and paste the FASTA file provided (which was retrieved from the Haemophilus influenzae genome sequence in ENTREZ GENOMES:MICROBES) into the ORF Finder sequence box (http://www.ncbi.nlm.nih.gov/gorf/gorf.html), select “1 Standard” and hit the as the Genetic Code and click on the “OrfFind” button.
  2. See the resulting output of the ORF Finder algorithm—Note that there is only one very large open reading frame in the region (see FIG 1)
  3. Select the largest open reading frame, and when the screen refresses, run a blastp search from the ORF Finder using the default configurations.
  4. Note that in the resulting list of BLAST there is a result that indicates near identity with the well characterized DNA mismatch repair protein MutL of Escherichia coli

FIG 1: ORF Finder Results for User Question 1 Search


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Revised 07/23/2007