Seqanswers Leaderboard Ad

Collapse

Announcement

Collapse
No announcement yet.
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • high number of denovo OTU

    Hi everyone, I am using QIIME to analyse my 16S V3-V4 gene illumina dataset.

    I have 2 groups of data and each group consists 10 datasets.
    I have filtered and combine all 20 set of data and resulting an input file with 3 million of reads.

    After I executed pick_open_reference_otus.py against 97_otus.fasta from greengenes.

    There is a file 'rep_set.fna' in the output otus directory.
    There are over 20k sequence in the rep_set.fna
    Only around 300 sequences match with greengenes.
    And around 300 otus are New Reference OTU.
    Remaining 17k otus are New clean up reference OTU.

    Is is normal to have this high no. of denovo OTU?
    How should I deal with these denovo OTU? Because they cannot be assigned to any taxonomy in greengenes reference set, what further analyses can be done on them? Thanks!

Latest Articles

Collapse

  • seqadmin
    Current Approaches to Protein Sequencing
    by seqadmin


    Proteins are often described as the workhorses of the cell, and identifying their sequences is key to understanding their role in biological processes and disease. Currently, the most common technique used to determine protein sequences is mass spectrometry. While still a valuable tool, mass spectrometry faces several limitations and requires a highly experienced scientist familiar with the equipment to operate it. Additionally, other proteomic methods, like affinity assays, are constrained...
    04-04-2024, 04:25 PM
  • seqadmin
    Strategies for Sequencing Challenging Samples
    by seqadmin


    Despite advancements in sequencing platforms and related sample preparation technologies, certain sample types continue to present significant challenges that can compromise sequencing results. Pedro Echave, Senior Manager of the Global Business Segment at Revvity, explained that the success of a sequencing experiment ultimately depends on the amount and integrity of the nucleic acid template (RNA or DNA) obtained from a sample. “The better the quality of the nucleic acid isolated...
    03-22-2024, 06:39 AM

ad_right_rmr

Collapse

News

Collapse

Topics Statistics Last Post
Started by seqadmin, 04-11-2024, 12:08 PM
0 responses
30 views
0 likes
Last Post seqadmin  
Started by seqadmin, 04-10-2024, 10:19 PM
0 responses
32 views
0 likes
Last Post seqadmin  
Started by seqadmin, 04-10-2024, 09:21 AM
0 responses
28 views
0 likes
Last Post seqadmin  
Started by seqadmin, 04-04-2024, 09:00 AM
0 responses
53 views
0 likes
Last Post seqadmin  
Working...
X