Team:UCL/Labbook

From 2013.igem.org

Revision as of 14:07, 9 September 2013 by Kckiew (Talk | contribs)

June

Week 1-3

No lab work

Week 4

26th June - We are given safety training in the Advanced Centre for Biochemical Engineering in all relevant laboratories, as well as general procedures in case of emergency.

July

Week 5-6

No lab work

Week 7

Bacterial Lab

15th July - The team is introduced to the laboratories which will be used during the summer for both bacterial and mammalian experiments.

16th July - 5X M9 salts [link to protocol], minimal agar [link to protocol], 1.4% molten agar solution [link to protocol] and 0.1M CaCl2/15% glycerol [link to protocol] were prepared for the generation of competent cells. Minimal agar plates were poured and streaked [link to streaking protocol] with W3110 Escherichia coli cells and left overnight to incubate at 37C.

17th July - Very little colony growth was observed from W3110 E.coli streaked plates. Plates were therefore left to incubate for a further 17 hours.

18th July - Sufficient colony growth allowed for the selection of a single colony from each plate. This was then inoculated in 5ul LB media [link to LB recipe] + 100ul 1M MgSO4 and left to incu-shake overnight at 37C.

19th July - Cultures re-suspended in new LB media and 100µl aliquots placed into individual eppendorf tubes for placement at -80C.

Mammalian Lab

17th July - Mammalian cell culture and maintenance [link to mammalian protocol] training by Mrs. Ludmilla Ruban. Passaged primary MEF (mouse embryonic fibroblast) cells. Passage 3.

18th July - MEF passage 4

19th July - MEF passage 5

Week 8

Bacterial Lab

22nd July -Transformation [link to transformation protocol] of our competent cells with plasmid YB3110 was carried out.

23rd July - No colony growth was observed on Ampicillin plates [link to ampicillin plate protocol] indicating no plasmid uptake. Transformation was repeated with YB3110.

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 0
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 0

24th July - No colony growth from main experiment indicating no plasmid uptake. Transformation was repeated.

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 0
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 0

25th July - No colony growth and hence no plasmid uptake. Transformation was repeated.

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 0
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 0

26th July - Once again our cells were unsuccessful in taking up the YB3110 plasmid. We concluded that our batch of competent cells were not competent and so these will not be used in any further experiments. A new batch of competent cells are to be generated.

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 0
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 0

Mammalian Lab

22nd July - MEF passage 6. Training ends.

Week 9

Bacterial Lab

29th July - A glycerol stock of pSecTag2A from 2009 was restored. This was streaked onto 3 plates (2x LB Amp and 1x No drug), additionally four Falcons with 2ul LB were inoculated with the glycerol stock (2x LB No drug, 2X LB Amp). These were left to incubate overnight.

30th July - pSecTag2A Amp and No drug cultures were centrifuged (5 minutes at 4000rpm) and the pellet frozen to be used later in a miniprep. pSecTag2A plates displayed good colony growth. Colonies were picked from non-competent W3110 streaked plates and inoculated in LB ->incu-shake 37C o/n.

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 100+
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 0

31st July - A new stock of competent cells was generated and stored, these were tested for competence via transformation using pSecTag2A and streaking onto amp plates -> incubate 37C o/n.

Ampicillin [link to Ampicillin protocol] was produced and stored. Following miniprep of pSecTag2A [link to miniprep anachem protocol] a gel [link to gel protocol] was prepared for analytical digest with HindIII [link to HindIII conditions] [insert gel image HindIII analytical digest of pSecTag2A]. 50X TAE diluted to 1X [link to dilution protocol].

Item Volume (ul)
DNA pSecTag2A 5
HindIII 1
Buffer 1
BSA 0.5
dH20 2.5
Total 10

Results displayed uncut bands at expected lengths. However HindIII cut pSecTag2A wells displayed too many bands, indicating possible contamination or uncut DNA.

August

1st August - Results from newly generated competent cells transformed with pSecTag2A:

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 100+
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 10

This indicated that the cells are more competent than the last batch, although growth on the negative control was a cause for concern. Therefore the transformation procedure from yesterday was repeated to see whether the ampicillin was working -> plates left for incubation 37C o/n.

Transformation of competent cells with pSecTag2A. 100µl was then spread onto 6 plates (4x Amp, 2x No drug). Left to incubate o/n 37C.

2nd August - Plates displayed significant colony growth on Amp plates indicating successful transformation. Negative control however displayed slight colony growth - ampicillin not working effectively, new ampicillin was therefore prepared. End of week inventory was recorded and stocks were topped up.

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 100+
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 15

Mammalian Lab

29th July - Thawed [internal link to mammalian protocol] and revived HeLa cells, grown in two T25 flasks in DMEM + 10% FBS + 2 mM L-Glu

30th July - HeLa cells are not looking very happy, with many floating cells. Cells are left to grow over the weekend

Week 10

Bacterial Lab

5th August - The new batch of ampicillin was tested via transformation of competent cells with pSecTag2A. Plates were spread and incubated 37C o/n.

6th August - Results from yesterday’s transformation:

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 (Main) Yes Yes 100+
2 (Positive Control) No Yes 100+
3 (Negative Control) Yes No 15

This indicates that there is still an issue with the ampicillin, possibly a problem with the stock powder used. A final test with both old and new ampicillin was carried out and compared without plasmid insertion.

7th August -

Vial Ampicillin Plate Plasmid Insertion Colony Count
1 Old Ampicillin Yes Yes 100+
2 New Ampicillin v2 No Yes 100+
3 Positive Control Yes No 15

Results indicated that the ampicillin source may not have been fully functional, therefore a new source of amp powder was located and amp was remade.

8th August - Preparation of 4x Amp plates and 4x no drug plates for storage in the fridge.

9th August - Meeting with Darren Nesbeth, requirements for upcoming weeks: create glycerol stocks of both pSecTag2A and pSB1C3, purify and extract pure DNA for pSecTag2A and pSB1C3.

Mammalian Lab

6th August - Checked HeLa cells. Cells are growing slow, left to grow for a few more days

8th August - HeLa cells are about 30% confluent. Changed media.

Week 11

Bacterial Lab

12th August - Chloramphenicol [link to Chloramphenicol recipe] was produced and stored at -20C. In order to produce glycerol stocks, pSecTag2A and pSB1C3 were inoculated with LB media in two falcon tubes each (1x drug, 1x no drug), two plates for each plasmid were also streaked (1x drug, 1x no drug). All were left to incubate at 37C o/n.

13th August - Results from the following plates:

Vial Ampicillin Plate Plasmid Insertion Colony Count
pSecTag2A Cells Yes Yes 100+
W3110 Cells Amp Yes No 0
pSecTag +ve control No Yes 100+
PSB1C3 Cells Yes Yes 0
W3110 Cells Chlor Yes No 25
PSB1C3 +ve control No Yes 0

This indicated that the pSecTag2A cells are acceptable to use for glycerol stock [protocol for generating glycerol stocks] generation and also for plasmid purification. Miniprep was performed on the two incubated Falcon tubes from yesterday.

The results concerning pSB1C3 indicated that the chloramphenicol did not work, and the glycerol stock is dead. Therefore a new glycerol stock was sought after and chloramphenicol was remade. Amp & Cmp were remade and pSB1C3 was located in the 2012 distribution kit. Amp & Cmp were both tested by producing 1x positive and 1x negative plate for each antibiotic streaked with W3110 cells ->left to incubate o/n at 37C. Glycerol stock of pSecTag2A was grown, and a miniprep was carried out. PCR could not be carried out as the primers for pSecTag2A had not arrived.

14th August - Two analytical digests of pSecTag2A with EcoR1-HF and Dpn1 were carried out.

Item A Volume A (ul) Item B Volume B (ul)
pSecTag2A 5 pSecTag2A 5
EcoR1-HF 1 Dpn1 1
Buffer 4 1 Buffer 4 1
BSA 0.5 BSA 0.5
dH20 2.5 dH20 2.5
Total 10 Total 10

[insert image of gel]

[link to enzyme conditions]

The pSB1C3 glyc stock (from HQ) was from the 2012 iGEM box in MMP -20C

Told to use a ratio of 3:1 inoculum:80% glycerol when making glyc stocks

Darren's instructions:

pSB1C3

Transfer entire glycerol tube contents to 10mL LB ND in a 50mL Falcon & measure OD. Place in 37C shakee overnight. Measure OD next morning. If there is growth in the inoculum use a loop to streak onto cmp and ND plates again.

pSecTag2A

50ul of 2013 pSecTag2A glyc stock to inoculate 10mL LB Amp in a 50mL Falcon. Grow overnight and the next day generate 15x glyc stocks sing 1.5mL eppendorfs -> store in MMP -20C.

15th August - OD results for pSB1C3 LB ND inoculum

Plasmid OD Before OD After
PSB1C3 (LB ND) 0.052 0.5