Antibiotics for use in culture media?

[Spirochete]

I have a couple questions about using antibiotics in culture media to prevent contamination while growing protozoa:

1) Where would be a good place to look for cheap generic antibiotics to use for this purpose?

2) I'm looking for an antibiotic that kills most gram negatives but has no effect on eukaryotic mitochondria. This rules out kanamycin and other aminoglycosides because they act on the 16S ribosomal subunit which is present in mitochondria. If it kills gram positives too that's great. I also value cheapness.

[Ouabache]

I would start with a literature search on selective media used for you particular protozoan?

In my research, I've used selective media for a particular fungus Macrophomina phaseolina, To eliminate bacteria, this included acidification and the aminoglycoside, streptomycin. Evidently protein synthesis of Macrophomina is not disrupted by this class of antibiotic. I don't recall where I ordered the streptomycin. If this is for educational research, you may be able to get a discount by ordering directly from the manufacturer.

[Monique]

Just look on Invitrogen
http://tools.invitrogen.com/search/index.cfm?searchterm=antibiotic&fuseaction=search.simplesearch&navFilter=%7C%7Ctaxonomy%3A%2FApplications%2FCell%20Culture

[Charion]

Anything targeting the bacterial cell wall should do fine. Like e.g. ampicillin.

[Andy Resnick]

I have a couple questions about using antibiotics in culture media to prevent contamination while growing protozoa:

1) Where would be a good place to look for cheap generic antibiotics to use for this purpose?

2) I'm looking for an antibiotic that kills most gram negatives but has no effect on eukaryotic mitochondria. This rules out kanamycin and other aminoglycosides because they act on the 16S ribosomal subunit which is present in mitochondria. If it kills gram positives too that's great. I also value cheapness.

I agree with Monique- check Invitrogen's website. They have a lot of tutorial information available.

I use ampicillin (resistance) to select out transfected bacteria, which may work for you as well.