16s rDNA sequence

4 posts / 0 new
Last post
mdwasi's picture
16s rDNA sequence

hi everybody!!!!

i am doing B-Tech in biotechnology & i want to do project. i got a topic about 16s rDNA sequencing of microbes, so can anyone tell me what is 16s rDNA sequencing technique???

also, when i searched about it on net, in its description there was rRNA in bracket { rDNA(rRNA) }, is rRNA & rDNA sequence one & the same?

cfish's picture
rRNA= ribosomal RNA

rRNA= ribosomal RNA
rDNA= ribosomal DNA

rDNA can also be linked to recombinant DNA.

skbiotech's picture
 r RNA & rDNA sequence is not

 r RNA & rDNA sequence is not the same...
i have also got a project on this samw topic...
if  you have more information is this topic you can send me some details.
on my email id.

Ivan Delgado
Ivan Delgado's picture

rDNA, or ribosomal DNA, is the genomic sequence that encodes the ribosomal RNAs (rRNA). The main difference between these two is that rDNA is a repeating sequence in almost all microbes (the typical bacteria has 7 or so repeats of any given rDNA). When these repeats are transcribed you get rRNA, which is then incorporated into the ribosomes that will turn mRNA into protein. 
rRNA can make up to 90% of total RNA, so it is by far the most abundant RNA in any organism. rDNA makes up a tiny portion of any organism's genome (a fraction of a percent). 
rDNA sequencing is very useful because it can detect the very small differences in DNA sequence between one rDNA and another. Because there are so many copies of rDNA in microbes and they are highly stable, these sequences are great molecular markers to genotype what kind of microbe you have in your hands. In essence, rDNA is the sequence of choice for differentiating one microbe from another. Of course you could always sequence the whole genome of the microbe and get better data, but sequencing an rDNA region like the 16S gene is a quick, and efficient, way of differentiating one microbe from another.