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Missing rRNA bands - (Mar/17/2006 )

Hi everyone,

I'm currently working on total RNA extraction from bacteria strains. I'm using kits for the extraction and the problem occurs where I can't get the two rRNA bands on the gel picture, whatever I obtained was an intense clump of RNA, which I think was the mRNA....

Can anyone please help me out? Where did my rRNAs have gone to?

Thank you very much in advance. Really appreciate your help.

Best wishes,


may you post your picture?
I think that assuming that mRNA are only 2% of total cell RNA, rRNA shouldn't be the species that disappear in first... Think of a pb of buffer or rnase contamination



I'm back with the gel photo. The second lane in the photo is my sample, which I heated at 65C for 10 minutes before loading; whereas the sample in the first lane is the one without heat treatment.

What I have in mind now is that the RNAs kinda clump together (including the rRNA?), and as I heat my sample, the conformation of the RNA changes and showed up in the gel as lane two in the photo.

What I would like to know now is that why does the RNA "clump" up together and how do I prevent this to happen during the preparation (without heating up my sample like what I did) of the total nucleic acid (RNA and DNA (which is the upper band shown in the gel))

Thank you so much for the helps.


Attached File


well to be honnest, that doesn't fit with what i regulary see with my RNA...
how much did you load on the gel?
to be honnest, this picture shows for me RNA at the bottom and plasmid DNA at top. such if it was a miniprep!....
I only can tell you at this tim to redo your extraction.