Saturday, February 25, 2012

Bacteria Transfer Genes without Sex???

Sketchy title right ^^??? Well it might be exactly what you are thinking ;{). The article is basically about how bacteria are able to adapt to fast changing conditions, in the absence of sex. The answer to this phenomenon is yup, you guessed it: gene transfer!

The beginning of the article talks about how "oceans are highly dynamic habitats." When an oil spill occurs it makes a bunch of liters of hydrocarbons available to eat. "Without sex—and many bacteria don't have sex thank you very much—it's harder for marine microbes to mix it up and achieve the genetic diversity that's key to population success." In order to quickly adapt, horizontal gene transfer (HGT) occurs. Horizontal gene transfer is the primary reason for bacterial antibiotic resistance.

(The image above is microbe called Rhodobacter capsulatus, which can release packets of genetic material that allow them to swap genetic code.)

Next the article explains how Lauren McDaniel, a marine biologist of the University of South Florida and her colleagues tested the gene transfer abilities of nine alphaproteobacteria. Whoa, lets stop for a second because you might be just as confused as I am...what the poop is alphaproteobacteria? To answer that question, alphaproteobacteria is a class of bacteria included in the phylum "Proteobacteria." This specific type of bacteria have gene transfer agents (GTAs) or, "little genetic escape pods" according to McDaniel.

Now that we got that confusion out of the way, once they completed their research, McDaniel and her team found that these packets were absorbed by their fellow bacteria and incorporated into their own genetic code. "These particles were able to transfer genes from a donor strain to wild-type bacterial strains as well as natural populations," McDaniel explains. When they observed the bacteria they noticed that the bacteria were transferring genes to not only their own species but also to other closely related bacteria and genera. Not only were they able to transfer genes from different species, they were also able to do it hundreds of millions of times more frequently than previously estimated for other methods of gene transfer.

To be honest, that is quite cool (haha I'm such a nerd). Anyways according to molecular biologist Ford Doolittle of Dalhousie University, the overall impact of this type of gene transfer may be limited. Why you may ask? Well given that the DNA fragments transferred were quite short in length, only being 500 to 1,000 base pairs long. However, HGT is an effective weapon in the bacterial evolutionary supply and is responsible for many of the genes present in today's microbes not only in bacteria, but also the ocean, which can be viewed as a "bit of a microbial DNA soup." Ewww DNA soup.

Article:

No comments:

Post a Comment