Hey, I think that TSB medium supplemented with 10% glycerol, kept in -70C would be enough

Hello Luis,

I've worked with glacier ice bacterias and I can give you some advices. First, what's your goal? To cultivate these bacteria or to extract total DNA for metagenomics/etc ? In case you want to cultivate them, just keep the ice cores frozen on -20°C until you get in your lab. Its hard to keep such conditions in the field, but try to put the samples in a freezer (ice cold or 0°C is ok for a couple hours) and then drop them in a -20°C as fast as possible. In my previous experience, I sampled the ice cores and kept them in a 0°C hand-freezer for 4 hours and then put them inside a -20°C freezer (on an oceanographic ship). The samples came to Brazil later after 3 months and I could work with both cultivation and molecular methods without problems.

I agree with Rubens. It depends on your goal, but really in both cases keeping them cold is the key. The only thing I would add is to avoid freeze thaw cycles if at all possible. It may be the biggest factor in damaging the cells and the DNA for molecular work.

We're doing a great deal of work with water samples right now for high throughput sequencing for 16S identification. This may be where I can best help. If this is the direction you want to go, I can pass along the Pace Lab protocols I've just updated. I think they would work well if you need to save sample space on your return trip. We filter our waters onto polycarbonate or polyethersulfone (I would recommend the latter for your work) until the filter is more or less dry, then store in a tube or in a cartridge on dry ice until we can get them back to lab. In your case, if your really do need to save space, melt the waters while keeping it under 4C, filter, and freeze. The key here is getting as much water out of the filter as possible to avoid the ice crystal formation in refreezing them.

I agree with Rubens and Kevin. Keep them as cold as you can for a couple of hours, then freeze them in at least -20°C and avoid too much freeze-thawing -it may kill your bacterial cells or only a few may survive.

I agree it depends what you want to do with the samples.

In case you are focused on RNA work it is enough to use Giagen, RNAlater. It also works with DNA. http://www.qiagen.com/products/rnastabilizationpurification/rnalaterrnaprotectsystems/rnalaterrnastabilization.aspx#Tabs=t0 It really works.

In that case you don’t need to keep your samples cold. Keeping cold can be problematic for transportation with several airlines.

Thanks every one for the very good advices. Kevin, do you have some paper about the strategy of melting and filter the ice and transport the filters?

Thanks against.

Freeze-dry the samples and like this, they can stay for years without loss of viability

You could gently release bacteria from a glacier, and then add the water suspension of bacteria to a special  liquid biopolymer. After polymer polymerizes, the bacteria will be suspended in a solid biopolymer in a dormant condition for a long time (months). When it arrives at your laboratory, the polymer can be dissolved with a water buffer releasing the bacteria. The complete procedure is described in our review “Biopolymers for sample collection, protection, and preservation”, attached.

Thanks Dr. Vodyanoy for your answer and paper.

I am grateful for your help.