bio.display

Through a very nice discussion with Maarten de Smit, we came up with additional approaches to replace laboratory-grade material with widely available alternatives in our quest for kitchen-grade DNA transformation. The results include marmite, red wine and Indonesian pudding.

LB

The medium used to grow E. Coli in is called LB, short for Lysogeny Broth. This contains nutrients that the bacteria likes, so that it grows well in it. A typical LB solution is made up of the following ingredients:

• tryptone
• yeast extract
• NaCl

An idea is to replace the above with the following ingredients, respectively:

• milk powder
• marmite
• table salt

(well, table salt is just the common name for NaCl anyway)

Arabinose

Arabinose is the promoter used in our DNA that makes the bacteria start expressing the fluorescent protein – in a way, switching on the fluorescent protein gene. According to [del Alamo], red wine contains arabinose in concentration levels that are sufficient for our needs. One needs to evaporate the alcohol from the wine first, as that would kill the bacteria.

Agar

Bacteria is grown on an agar gel for convenience, which is coincidentally used in East-Asian cuisine as well. So one just needs to get to a proper food store to get some.

Centrifuge

The process of creating competent cells involves centrifuging the sample, so as to collect all the cells together, and that one can get rid of the liquids around it. But bacteria cells can also be collected using filters aimed at creating sterile solutions, which in fact trap the bacteria. Filters of 20μm or 45μm are sufficient at trapping bacteria.

Need to do some further investigation though on where to get such filters, like in a pharmacy, for example.