Re: [DIYbio] How do you grow specific types of bacteria?

Depends what you want to isolate. Some are very easy to isolate because
they have traits (ability to grow at low pH, high salt, low
temperature, without sugar, with odd sugars, with alcohol... etc) that
can be easily selected for. Others are hard to isolate but easy to
identify. I would say that most are easy to grow but hard to identify,
and most are medium difficulty to isolate by differential methods
without specialised ingredients.

However, some species will be next to impossible to identify or isolate
without special equipment or ingredients, often species you would
expect to be easy. I spent a good few evenings digging into Bacilli,
trying to find a way to isolate *just* bacillus subtilis, or even its
close relatives, from soil samples, and not B.anthracis or B.Cereus.
Sadly, it turned out to be the sort of thing that requires equipment,
technique and sometimes ingredients that won't be on-hand for most. I
could do it, because I'm a microbiologist, but it wasn't worth trying
to write up a how-to.

On the other hand, isolating V.phosphoreum is *easy*: You leave an
unwashed, unfrozen squid in a fridge (one you're not using for food!)
in a salt-water + glycerol solution until it goes bad, and look at it
in a dark room for glowing spots. Isolate the blue ones, grow on LB
agar + glycerol + salt to 32g/L, at 4C in the dark. Very little else
will grow at 4C at that much salt, except perhaps S.aureus, and even
then competitors will grow very slowly, and *don't glow in the dark*.

So, it depends on the species. Some are easy, some are hard. The main
thing is knowing!

On Sun, 1 Dec 2013 17:58:51 -0800 (PST)
V Shenoy <vshe...@gmail.com> wrote:

>
>
> Hi I am new to Diy bio, and I was wondering if I could get some help
> from you guys. I was wondering if any of you had any advice on trying
> to grow specific types of bacteria. By this I mean that I want to
> grow bacteria with specific traits. I am trying to do this on a
> fairly low budget (so no buying bacteria) but I have sufficient lab
> space, a microscope, and other equipment needed for growing bacteria.
> I would really appreciate it if you could help me. Thanks!
>