• Question: Are all bacteria completely different and unique?

    Asked by kirasilverlock to Asif, Laura, Lena, Sean, Viv on 20 Mar 2012.
    • Photo: Lena Ciric

      Lena Ciric answered on 20 Mar 2012:

      This is a great question. The short answer is no.

      There are many different species of bacteria. We don’t yet know how many as we’re not able to grow all of them in the lab. There are also many strains of each species – like all breeds of dog are the same species but are genetically different and look different. And there will be different strains within the strains. However, eventually you will get down to clones. Because bacteria don’t reproduce sexually, but they divide, the DNA in the daughter cells will be the same as in the mother cell. And division can happen as frequently as every 20 minutes, so you can end up with a lot of clones pretty quickly.

      Mutations can happen during this process and will then be passed on when the cell next divides. This is how the bacteria evolve. Bacteria can also trade DNA when the conditions are right. This is sort of like bacterial sex and can take place between different species. This is how the genes I study that make them resistant to antibiotics often move from one species to another.

    • Photo: Sean Murphy

      Sean Murphy answered on 20 Mar 2012:

      Lena gives a good explanation. All living things share some similarities, due to the fact that we have common ancestors. However, it is the differences between living things that allows us to evolve. So like everything else, bacteria have some similarities and some differences.

Comments