Team:Cambridge/Diary/Week 11

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=== Monday ===
=== Monday ===
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The gibson control plates from yesterday showed that there is no significant difference between the competency of our cells, or our master mixes. However PJ obtained a >10x greater efficiency.
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We continue trying to debug the Gibson reaction, with incremental success. The Gibson control plates from yesterday showed that there is no significant difference between the competency of our cells, or our master mixes. However PJ obtained a 10x greater efficiency.
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We decided to rule out a problem with the plates. He'd been pre-warming them, I hadn't. I assembled and transformed again, using 2x our plates and 2x his plates, one warm and one straight from the fridge.
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We decided to rule out a problem with the plates. Prewarming does not appear to be a factor in the success of the plating step.
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A Germination medium has been determined and the protocols for imaging the sporulation and germination of B.subtilis have been ironed out.
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Paul's been working on developing his germination protocols. Germination medium has been determined and the protocols for imaging the sporulation and germination of B.subtilis have been ironed out.
=== Tuesday ===
=== Tuesday ===

Revision as of 12:17, 7 September 2012

Week: 3 4 5 6 7 8 9 10 11 12

Contents

Monday

We continue trying to debug the Gibson reaction, with incremental success. The Gibson control plates from yesterday showed that there is no significant difference between the competency of our cells, or our master mixes. However PJ obtained a 10x greater efficiency.

We decided to rule out a problem with the plates. Prewarming does not appear to be a factor in the success of the plating step.

Paul's been working on developing his germination protocols. Germination medium has been determined and the protocols for imaging the sporulation and germination of B.subtilis have been ironed out.

Tuesday

Gibson control plates from yesterday showed no difference between PJs plates and ours.

Paul Grant, another member of the Haseloff lab, suggested that he observe Tom assemble and transform, but failed to detect any gross incompetency. We thought that the problem might be the PCR machine - it takes a little while to load ours, whereas the Haseloff lab's is a hotblock that can be preheated, minimizing the time the T5 exo has to digest our fragments.

New control fragments were obtained, some with different "minelute" gel extraction kits. One assembly was set up with mineluted control, the other with normally extracted control. Additionally, a reaction was set up to assemble our 4-part ratiometric construct. We used the Haseloff hotblock PCR machine to assemble. Transformation was done with our competent cells, and they were plated.

Work has begun on designing gibson primers to make a biobrick out of a plasmid containing the spoVAA gene under control of the PssB "fast" promoter. Peter Setlow's team from the University of Connecticut have kindly offered to send us the B. Subtilis strain containing the modified chromosone and two E.coli cultures containing plasmids used to facilitate the single crossover recombination event that placed spoVAA under the control of PssB. Designing Gibson primers may prove a little tricky though as we don;t have access to the full sequence.

Wednesday

Only one of the control plates from yesterday (the minelute control) has colonies on it, and still a low number. The other has none on it at all. The ratiometric construct plate has a couple of colonies on it, but their lack of fluorescence implies that they are not what we want.

A gel was run to check the control fragments. (5ul of each 10ul elution). No significant differences observed between fragments, all were visible and correctly sized.

Thursday

Friday