My name is Hilary Brown I work at the Wellcome Trust Sanger Institute.
I'm currently studying for a PhD based on the Intestinal Microbiota of the Human Gut.
The human intestinal microbiota is mostly made up of bacteria in addition to some viruses and fungi
and these bacteria act together as a community, so that they work with each other for their own benefit but for our benefit as well.
If there is an imbalance in this community and some species increase in abundance or others decrease
this can have a negative effect on our health.
We want to understand how this community affects our health and also identify ways to restore this balance again.
The majority of the intestinal microbiota are beneficial but some of them can be harmful and this is why we study them in a CL2 lab.
CL2 stands for Containment Level 2 and that means we have certain safety procedures in place to protect ourselves.
If you are taking antibiotics then you're not allowed to enter the lab.
This is because antibiotics - while they will kill the bacteria that are making you sick - they can also kill a lot of the good guys,
which causes an imbalance in your gut and leaves you more prone to further infection.
Only authorised people are allowed to work in the lab.
When I enter the lab I put on a lab coat and gloves. These protect me from any spillages or bacterial contamination.
Most of the bacteria that live in your gut are anaerobic; this means they cannot survive in the presence of oxygen.
Because of this we work with the bacteria in anaerobic hoods.
These cabinets are sealed. They are constantly being pumped with anaerobic gas that contains hydrogen, carbon dioxide and nitrogen.
This keeps all of the oxygen out and means the bacteria can survive inside them.
The first thing I need to do is to enter the anaerobic cabinet.
I place the sleeves over my arms and then by pressing these pedals, I can suck all of the air out of the sleeves.
The other pedal then blows more anaerobic gas into the sleeves.
I repeat this process three times to ensure I’ve removed as much oxygen as possible
before opening the doors and entering the anaerobic cabinet.
To study these bacteria we need to grow them on Agar plates.
The Agar that the bacteria grow on contains lots of nutrients that would also be present in the human gut.
When you streak the bacteria onto a new plate you can often see new colonies growing 24 hours later.
Here I have an individual bacterial species growing on a plate.
One of the jobs I regularly have to do is to re-streak these onto new plates.
This is because the bacteria will use up all the available nutrients.
When I'm working in the anaerobic hood I have to work aseptically.
This means working as clean as possible and trying to prevent contamination of my experiment.
For example, if I'm streaking bacteria on to a new plate, I will use an Inoculating loop but I will only use this loop once –
after using it I will discard it and I will use a new loop before moving on to the next plate.
There are two ways in which I study these bacteria; one is by understanding their phenotype.
This involves studying their biology; how they live and grow, how they respond to different environmental conditions.
The other is by studying the genotype. We extract the DNA from the bacteria and then we do whole genome sequencing of this DNA.
When the sequencing is finished I then analyse the data on my computer using various bioinformatic analysis tools.
Using these tools I can look at how closely related these bacteria are to each other
and I can also identify new species that no one has cultured before.
Studying the intestinal microbiota is very exciting because it's moving very quickly from basic research towards therapeutics.
This is unusual really for a field of biology, usually it takes a much longer time
before we start seeing new drugs and new medicines on the market place.