Question: What sort of techniques are used to isolate and identify the different micro-organisms?

Cat O'Connor answered on 16 Jun 2011:

Hi u27adamsm, conor719 and lynnpollock

Would you believe that a lot of the techniques we use today were developed hundreds of years ago, such as how to grow bacteria in the lab. Growing bugs in the lab on special food that allows them to grow (we call this agar) is used a lot even today and we can kinda find out what type of bugs we have in a sample by seeing if it’ll grow on all different types of agar that are made up with all different nutrients as different types of bugs need different types of nutrients to grow.

More recently, say since the 1960s, I think we’ve become a lot more smarter as microbiologists and we’ve started to use techniques collectively called molecular microbiology methods. There is so much you can learn about this type of identification method but the basics of it are that now we can use the DNA (or parts of it) of different bugs to identify which types of bugs they are. And often we combine growing bugs in the lab with molecular techniques to ge the full story.

For instance, the bug I study that causes TB in cows, we grow it in the lab first (and this bug is REALLY stubborn and can take up to a month to grow) and then we use techniques like spoligotyping or VNTR analysis (no need to worry what they are, just know that they both look at the bugs DNA) to see what different types of the bugs are in the sample. On my profile I go into this a little bit more if you are interested, but if you have any more questions, just ask!!

Hope this helps,

Cat