Team:Cambridge/LabBook/Week4

Monday

7. Experiment: Transformation of TOP10 cc (Ben, Emily, Bill, Hannah, Will & Anja)

Top10 cc taken out of -80°C freezer and tawed on ice. 1ml pipette tip cut with scissors sterilised with ethanol and flamed. Using cut pipette tip ~50μl of TOP10cc were transferred to 1.5ml Eppendorf tubes (3x)

1. 2μl of resuspended (in 10μl deionised water) BBa_J13002 (plasmiid with Tet^R represed PoPs/RIPs generator) was added.
2. 2μl of resuspended (in 10μl deionised water) BBa_I712019 (plasmid with firefly luciferase) was added
3. 1.5μl of pHK724 (plasmid containing lux4 gene) was addded

Ce]]s were held on ice for 30min. Heat shocked for 60s at 42°C (waterbath). As a control TOP10cc that had not been transformed with anything (no plasmid DNA added) were subjected to same treatment (as cells to be transformed). Put on ice for ~2min. Added 250μl pre-wardmed (in 37°C) SOC. Incubated at 37°C for Ph with rotation (Eppendorf tubes---> 12ml falcon tubes, tape over top). Plated 50micorl on pre-warmed (in 37°C incubator) LB agar plates with Amp (with blue L-shaped spreader). Grow colonies overnight at 37°2.

8.Experiment: Set up overnight culture of E.coli/pHK555 (Will & Anja)

Inoculated single bacterial colony (E.coli/pHK555) in 5ml LB in a 12ml falcon tube. Incubated at 37°C with rotation overnight. (Since it was difficult to see the colony sent from Jim Slock, we picked twice from where we anticipated colony to be and set up 2x5ml LB overnight cultures)

9.Experiment: Set up overnight cultures of W3110 hns 93-1, BW25113 Δhns::kan, W3110 hns-205::Tn10 Tet^R, GM230 hns-205::Tn10 Tet^R (Ben & Anja)

Inoculated single bacterial colonies in 5ml SOB (i.e. 4 different cultures), incubated at RT with shaking overnight.

Tuesday

10. Experiment: Preparing chemically competent cells (W3110 hns 93-1, BW25113 Δhns::kan,W3110 hns-205::Tn10 Tet^R, GM230 hns-205::Tn10 Tet^R (Ben, Will, Paul, Bill, Emily, Hannah & Anja)

(followed protocol for 'TOP10 chemically competent cells cells' from OpenWetWare) Inoculated 0.5ml of the 4 bacterial strains (overnight cultures) in 85ml SOB each. Incubated at 37°C with shaking (180rpm). put on at 11:55am

Bacterial Strains:

OD₆₀₀ measurements:

Cooled cells and (newly prepared) CCMB80 Buffer in ice bath for ~20 minutes. (4) was on ice for over an hour. (2) was on ice for ~40 minutes. (3) was on ice for ~40 minutes.

2 x 30-35ml of each of the four 85ml cultures were poured into 50ml falcon tubes. Centrifuged at 3000g at 4°C for 10 min. Discarded supernatant. Resuspended cell pellet in 20ml tube CCMB80 buffer (ice cold). On ice for 20 min. Centrifuged at 3000g at 4°C for 10 min. Discarded supernatant. Resuspended cell pellet in 5ml tube CCMB80 buffer. Incubated on ice for 20 min. Aliquoted 200μl portions into Eppendorf tubes colour-coded according to the above listed colour labels. Stored at -80°C

11. Experiment: Streaking out of bacterial cultures (E. coli/pHK555) (Paul & Anja)

On LB agar plates with Chloranphenicol: E. coli/pHK555 (from both overnight cultures) on two individual plates incubated at 37°C overnight.

12. Experiment: Set up overnight cultures (TOP10 with BBa-J13002, TOP10 with BBa_I712019) (Ben & Anja)

Results from transformations on 02/08/10

• Colonies grew for TOP10 cells transformed with BBa_J13002 (promoter + rbs) and those transformed with BBa_I712019 (firefly luciferase) :-)
• no cells grew for untransformed TOP10 cells plated on LB agar + Amp plates (neg control)
• small (but plenty) colonies grew for TOP10 cells transformed with pHK724, these were left in the incubator for another 24h, and then put at 4°C

Inoculated single bacterial (TOP10 with BBa-J13002 and TOP10 with BBa_I712019 individually) colony in 5ml LB, incubated at 37°C with shaking (180rpm) overnight

Wednesday

13. Experiment: Measuring competency (W3110 hns 93-1, BW25113 Δhns::kan, W3110 hns-205::Tn10 Tet^R, GM230 hns-205::Tn10 Tet^R) (Theo & Hannah)

Followed protocol under 'TOP10 chemically competent cells' from OpenWetware

Competent cells from all 4 different strains taken out of -80°C freezer and thawed on ice. 1ml pipette tips cut with scissors dipped in ethanol and flamed. For each strain 50μl of cells were transferred to a separate 1.5ml Eppendorf tube. 1μl pUC19 (standard plasmid) was added to each 50μl of cells. Held on ice for 30 min. Heat shocked at 42°C for 60s (water bath). On ice for ~2min. 250μl SOC was added to each of 4 tubes. Each Eppendorf tube was put in a 12ml falcon with tape over the top and incubated at 37°C for 1h with rotation. 20μl of each of the 4 different transformed strains were plated on LB agar plages with Amp. Colonies were grown overnight at 37°C.

14. Experiment: Making competent and transforming E. coli/pHK555 (Peter & Paul)

50μl EZ Comp buffer transferred to Eppendorf tube and placed on ice. Single E. coli/pHK555 colony resuspended in EZ Comp buffer(2x single colony in 50μl EZ each, 1 streak of colonies in another 50μl EZ). Vortex if needed to suspend clumps. 3μl of pHK724 plasmid added to solution, mixed and incubated on ice for 20 min.

Heaat shocked at 42°C for 90s (water bath). Incubated at RT for 5 min. 1ml LB added. Eppendorf tubes put in 12ml falcon tubes with tape over top. Incubated at 37°C for 1h with rotation. Plated 100μl on LB agar plates with Cm and Amp. Incubated at 30°C for 48h.

15. Experiment BioBrick Standard Assembly (Emily & Bill, Paul & Anja)

Took overnight cultures of

1. TOP10 with BBa_J13002 (plasmid with promoter + rbs)
2. TOP10 with BBa_I712019 (plasmid with firefly luciferase)

Plasmid DNA Purification

following the "QIAprrep Spin Miniprep Kit using a Microcentrifuge" protocol.

Restriction enzyme digest

Prepared at RT in the listed order:

It was checked (Nanodrop!) that 2μl of plasmid DNA would not contain more than 1μg of DNA. The reaction mixtures were mixed gently (flick tube) and spun in the microcentrifuge for 15s (13,000 rpm). It was then incubated at 37°C (water bath) for 30 min.

Gel Electrophoresis

An E-gel EX Agarose 1% was mounted on the transilluminator. Nanodrop readings were taken for both restriction enzyme digests:

• Plasmid with promoter + rbs: 21.4 ng/μl => 5μl gives 100ng
• Plasmid with luciferase: 19.7ng/μl => 5μl gives 100ng

For each digest the following mixture was made up

• 3μl 6X orange loading Dye
• 5μl plasmid DNA (restriction digest)
• 12μl deionised H₂O

Gel was loaded according to the scheme below:

Empty wells were filled with 20μl deionised H₂O. Gel was run and DNA gragments of appropriate sizes were observed:

• plasmid with promoter andd rbs => 2153b
• plasmid without luciferase => 3426b
• firefly luciferase => 1653b

The plasmid with promoter + rbs as well as te firefly luciferase bands were cut out of the gel (gel cut pipette tips) and DNA was extracted separately from the two gel pieces by following the QIAquick Gel Extraction Kit protocol.

Ligation

Fermentas 5X Rapid ligation buffer was taken out of -20°C fridge, thawed and mixed thoroughly prior to use. Nanodrop measurements of the linearised vector DNA as well as the insert DNA were taken:

• plasmid with promoter + rbs: 56.8ng/μl
• firefly luciferase: 29.6ng/μl

10-100ng of linearised vector DNA should be added to the ligation mix=>1μl. 3:1 molar exess of insert DNA should be added to the ligation mix.

(56.8ng.2153b) * 1653b * 3 = 131ng => 4.5μl

Added to a mirocentrifuge tube:

The mix was vortexed and spun for 15s in the microcentrifuge (13,000 rpm). It was incubated at 22°C (RT) for 30 min and stored at 4°C.

16. Experiment: Set up new overnight cultures (TOP10 with BBa_J13002, TOP10 with Ba_I712019) (Peter & Anja)