what are the specific advantages of 16srRNA in biology?

Answer 1

16S rRNA gene is a highly conserved portion of the 30S ribosomal DNA of bacteria that "has been widely used as a molecular clock to estimate relationships among bacteria (phylogeny), but more recently it has also become important as a means to identify an unknown bacterium to the genus or species level." (http://www.cdc.gov/ncidod/EID/vol8no10/02-0391.htm)

Answer 2

Bacterial identification based on molecular methods, especially Polymerase Chain Reaction (PCR), sequencing of genes and coding for ribosomal 16S rRNA, has become a very important and sensitive technique in studying bacterial communities in environmental samples. The reason for this being that the ribosomal DNA is a very conserved area of the genome that includes variable regions. Many species-specific base-pair sequences exist within 16S rRNA and are therefore very useful for easy bacterial identification.

I don't know if you are familiar with the PCR process, but in order to amplify and isolated the 16S rRNA you would need to use DNA primers that hybridise (bind) to conserved (fixed sequences) regions of the 16S rRNA , but spanning variable regions in order to obtain PCR products with species-specific differences in base pair sequences.

This mixture of isolated and amplified 16S rRNA fragments can then be separated by denaturing gradient gel electrophoreses (DGGE). Therefore 16S rRNA can be used for easy and fast identification of bacteria and microbial population changes in a variety of food or environmental samples. It is much faster than conventional microbiological methods, since many microorganisms that can not be cultured on media, can now also be detected using 16S rRNA technology.

My knowledge on 16S rRNA is still limited, so I hope this bit of info answers your question.

Good luck