cofactors – SB209

Evening all!

Today consisted of A LOT of waiting! We started by washing the plugs in 1x wash buffer 4 times, for an hour each! This is to make sure that all the lysozyme and mutanolysin was removed. The plugs could then be stored in 1x wash buffer at 4°C.

We then put each plug into a separate eppendorf tube and washed once with 0.1x wash buffer for an hour, and then once more to ensure all EDTA had been removed, as it will remove cofactors that are very important to the restriction enzymes we want to use next! We then removed 3 plug eppendorfs, and put them into the fridge, in order to compare samples that were treated with restriction enzymes and those who weren’t. We removed the remaining buffer in the other 7, and added 1x restriction enzyme buffer to each, and left for an hour, at room temp. with gentle agitation. After this, we removed the restriction enzyme buffer, and added fresh restriction enzyme buffer, restriction enzyme (SpeI, which cuts at ACTAGT) and BSA (which acts as a crowder to increase conc. and allow increased collisions). This is to allow the fragmentation of our Propionibacterium acnes DNA, which is on average 100kb size fragments. We then incubated the plugs overnight.

Tomorrow we will be finishing off the plugs, preparing a new gel run and running a new gel with our home made plugs and new modifications.

See you all tomorrow! 🙂

Evening All! 🙂

Today myself and Jo came into the lab at 9am, and Mike gave us some new stuff to play with! – the newly arrived BioRad plug making kit and restriction enzyme digestion 🙂
We worked through the kit and information provided, made some notes and researched anything we didn’t understand online and through a discussion with Mike. We then produced a new COSHH assessment for our new procedure of making plugs and researched any modifications that journals mentioned when using Propionibacterium acnes specically.

We then made up a stock solution of Chloramphenicol (90 mg/ml), that we will need during plug production. It is a antibiotic, that is bacterial static and stops replication. We will also be using lysozyme, to break down cell membranes, Proteinase K, to break down protein and restriction enzymes, to cut up DNA specifically. Each also has a specific buffer, this is due to enzymes specific nature (pH, Cofactors). We also discussed why it was important to remove remaining EDTA, as it removes cofactors, which are very important to enzyme activity! We also discussed how obtaining the proper cell concentration within the plugs is most likely to be the most difficult part of production. In order to get the most accurate concentration we will be using an OD and CFU/ml against time to produce two sigmoid curves in order to work concentration out.

Excited to start practising these new techniques, so bring on tomorrow morning! 🙂

Tag: cofactors

Evening all Today consisted of A LOT of…

Evening All Today myself and Jo came into…