Welcome back to Microbial Mondays! Today, I'm answering a question that my Dad asked in response to a previous post that I wrote. Last month, I wrote about how I used E. coli as a tool to produce blueprints for the viruses that I use in my PhD research. If you haven't read this article yet, I'd recommend going back and reading it before reading on.
I'll pick up at the point where I left off: the point at which I have lots of E. coli cells which each contain plasmids. These plasmids have genes that encode the virus I'd like to make. Remember, plasmids are simply extra bits of DNA that I've stuck inside the E. coli, and that DNA includes blueprints for the virus, just the same as how human DNA is a blueprint for humans.
For me, the whole E. coli step of the virus production is actually only a tool to make more of these blueprints. You can think of it like a microbial photocopier. For instance, imagine that you would like one million identical bikes built in ten years. This is way too big of a job for just one person to make. You do the math, and you find that in ten years, one bike mechanic can build one thousand bikes. This means that you need a total of one thousand bike mechanics, each of whom build one thousand bikes, to get your one million bikes at the end of your time frame. Each of these mechanics needs an identical blueprint, so you get to work photocopying so that the mechanics can get to work quicky.
Making viruses is pretty much the same. To make good HIV in a reasonable amount of time, I need to give a bunch of "mechanics" a bunch of identical blueprints. In this case, the mechanics are just a type of human cell that is very good at making HIV (which can be kept alive more or less indefinitely, in the way that I explained last week), much like bike mechanics might be very good at making bikes. And, you guessed it – the plasmids are the blueprints.
Once I have stuck the plasmids inside the human cells, all I need to do is sit and wait. Just like I can engineer bacteria to make proteins or plasmids, I can engineer petri dishes of human cells to make viruses. At this point, they do all the hard work - leaving me with time to go on a bike ride and daydream about analogies!
Until next week - try building something yourself! It'll make you appreciate what cells can do.
~Alex