Team:Duke/Notebook

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Lab Notebook

From Google doc

April Overview

Objectives

This is what we were trying to accomplish in April.

April 7

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano and Matthew Faw

PCR of Z4EV from pMN10

  • new oligos SpeI-Z4EV5p and NcoI-spc-Z4EV3p (diluted to 100uM)
  • 4 tubes with 0, 0.3, 0.6, 1 uL template
    • iGEM 3-step protocol with 65C anneal, 20 sec extend
  • Note: did not dilute template beforehand (do this in future)

Results (04/08/2014): Lanes 2 and 3 produced band at ~0.7-0.8 kb (agarose gel)

  • Expected band size 715 bp
  • Control (no template) showed no band, lane 4 produced faint band
  • Lanes 3 and 4 showed strong band at ~5-6 kb (template expected 5.1 kb)

Next steps:

  • Run on gel to confirm (4/8)
  • digest PCR product and dCas9/Mxi1 with SpeI/NcoI to ligate (4/8)

April 8

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano

Agarose Gel with Z4EV PCR products

  • PCR from 04/07/2014 of Z4EV from pMN10
  • Results (04/08/2014): Lanes 2 and 3 produced band at ~0.7-0.8 kb (agarose gel)
    • Expected band size 715 bp
    • Control (no template) showed no band, lane 4 produced faint band
    • Lanes 3 and 4 showed strong band at ~5-6 kb (template expected 5.1 kb)

PCR cleanup of Z4EV PCR products

  • PCR from 04/07/2014 of Z4EV from pMN10
  • Used only lanes 2 and 3 (successful from gel)
  • Concentration 32.4 ng/uL in 50 uL

Restriction Digest of Z4EV PCR product and TDH3-dCas9-Mxi1

  • Both with SpeI-HF and NcoI-HF in Cutsmart
  • PCR from 04/07/2014 of Z4EV from pMN10 -- 50 uL (entire product) in 65 uL reaction
  • dCas9 plasmid construct from CC 190ng/uL -- 20 uL in 65 uL reaction

PCR cleanup of Z4EV PCR digest product

  • 04/08 digest of 04/07 PCR
  • Results: Final concentration negligible, no DNA

Next steps:

  • Z4EV PCR again from pMN10
  • Digest of PCR in SpeI/NcoI
  • Gel extraction of digested TDH3-dCas9-MxiI

April 10

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano

PCR of Z4EV from pMN10

  • Repeat of PCR from 4/7/14
  • Oligos SpeI-ZeEV5p and NcoI-Spc-Z4EV3p
  • Diluted pMN10 template to 1 ng/uL before use
  • 8 tubes: 0, 0.3, 0.5, 0.5, 0.7, 0.7, 1.0, 1.0 uL template in 50 uL reaction
    • iGEM 3-step protocol with 65C anneal, 20 sec extend
  • Results (see 4/11): expected bands present, but concentrations too low

Gel Extraction of backbone (-TDH3) from TDH3-dCas9-Mxi1 digest

  • Digest performed 4/8 with SpeI/NcoI
  • Expected band sizes: 10.5 kb (backbone, desired piece), 637 bp (TDH3, removed piece)
  • Obtained consistent band sizes, used 400 mg gel in extraction <
  • Gel picture:
  • Results: obtained 20 uL product at 55 ng/uL (froze for later use)

Next steps:

  • Run gel of PCR
  • Clean up PCR

April 11

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano and Matthew Faw

Agarose gel to analyze PCR of Z4EV from pMN10

  • PCR from 4/10
  • Expected band size: 715 bp
  • Showed band at expected size in all seven non-control lanes
  • Intensities appear low, increase in higher lanes (higher template conc.)
  • Gel picture:

PCR cleanup of Z4EV from 4/10 PCR

  • final concentration from 7 tubes: 25.8 ng/uL in 30 uL
  • Need to improve

Next Steps:

  • Redo PCR of Z4EV. Things to try:
    • Use previous cleanup as a template
    • use 1 uL enzyme instead of 0.5
    • slightly longer extension time
    • higher template concentration
  • PCR cleanup: Things to try:
    • Run PB buffer flow-through back through filter during step 7
    • let PE buffer sit in column (covered) while ethanol evaporates
    • let elution buffer sit on DNA for 2-3 minutes before spin

April 13 - Unfinished

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano and Garima Tomar

PCR of Z4EV from pMN10

  • Third attempt (previously 4/7, 4/10)
  • oligos SpeI-Z4EV5p and NcoI-spc-Z4EV3p
  • 8 identical tubes with 1.5 uL template (1 ng/uL stock) in 50 uL reaction
    • Used 1 uL polymerase (instead of 0.5 uL) per 50 uL reaction
    • iGEM 3-step protocol with 65C anneal, 1 min extension
  • Changes from previous: more template, more polymerase, longer extension

Results (Date):

  • ???

Next steps:

  • Run on gel
  • Clean up PCR with new notes (see 4/11), see if concentration is better

April 14

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano

Agarose gel of Z4EV PCR

  • Z4EV from pMN10, 4/13 PCR
  • 2-log ladder and 8 identical reaction tubes
  • Expected band size ~715 bp
    • All lanes showed band 700-800 bp
    • band intensity much greater than previous attempts
  • Unable to take normal picture: used dark room and iPhone camera to photograph

PCR cleanup of Z4EV PCR from 4/13

  • Qiagen miniprep steps 7-10
  • 8 tubes into 1 final product
  • Modifications to protocol:
    • ran PB buffer through twice
    • let column sit, covered, for 10-15 min after PE buffer wash/discard step
    • let water for elution sit on column for 3 min before spin
  • Results: Obtained 30 uL product at 407.5 ng/uL (in gel fridge for immediate use)

Next Steps:

  • Restriction digest of Z4EV and PCR cleanup with SpeI and NcoI
  • ligation of Z4EV with dCas9 backbone (obtained 4/10)
  • transformation

April 15

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano

Restriction Digest of Z4EV-PCR with SpeI/NcoI

  • PCR from 4/13, cleaned 4/14
  • Cut with SpeI-HF and NcoI-HF in Cutsmart buffer
    • 30 uL PCR product (407.5 ng/uL) in 50 uL reaction
    • Incubated at 37C for 4.5 hrs

PCR Cleanup of Restriction Digest of Z4EV

  • Qiagen kit with modified methods described on 4/14
  • Results: Obtained 30 uL product at 248.1 ng/uL DNA (nanodrop)

Ligation of Z4EV PCR and dCas9-MxiI backbone

  • Z4EV from pMN10, digested with NcoI and SpeI (4/15)
  • dCas9-MxiI backbone digested with NcoI and SpeI, extracted 4/10
  • 3:1 molar ratio backbone:insert
    • 20 uL total reaction - 15.3 uL backbone (55 ng/uL), 0.7 uL insert (248.1 ng/uL)
  • Left in cold room overnight in 16C heat block

Next steps:

  • Transform ligated plasmid into E. coli, clone, then miniprep.

April 16

Objective: Create Z4EV-dCas9-Mxi1 construct
Matthew Farnitano and Charlie Cooper

Transformation of ligated Z4EV-dCas9-MxiI plasmid into E. coli

  • Ligation left overnight for 22 hrs
  • Heat shock protocol with chemically competent E. coli
    • 1 sample plus 1 no-insert control
    • grown in SOC medium, plated on LB+Amp plates
  • Results (Charlie Cooper) (4/17): No colonies on either plate
    • Possibly used ineffective cells

Next steps:

  • Digest and gel extraction of backbone
  • Ligation and Transformation

May, June Overview

Objectives

This is what we were trying to accomplish in May and June.

May 29

Objective: Prepare Chemically competent E. Coli
Matthew Faw

Followed Charlie’s Cloning Protocols to prepare chemically competent E. Coli

  • Once E. Coli were prepared, the solution was aliquoted into 12 labeled tubes (450l in each tube) and tubes were stored in iGEM box in -80C cooler on far left

Next Steps:

  • Transformation

June 1

Objective: Transform Chemically competent E. Coli (CCEC)
Matthew Faw

Transformation of CCEC with RFP Construct of varying concentrations+control with no DNA

  • Followed Charlie’s Cloning Protocols
    • Mistakenly used all of DNA construct from the kit… So not sure if the transformation will be successful
  • Plated the transformed DNA and put in incubator at 37C
  • Results (6/2/14)--Transformation unsuccessful because improper procedure was done by MFaw

Next Steps:

  • Look at plates, compare cultures
6/2/14 Objective: Redo yesterday’s transformation Matthew Faw Due to my failure to correctly conduct the transformation yesterday, it was necessary to redo the transformation. Followed Charlie’s Cloning Protocols Added 1l of .5, 5, 10, 20, 50, and 0 (control) pg/lof RFP Construct to chemically competent E. Coli (CCEC), and followed procedure Plated the transformed DNA on 6 separate plates, put in 37C overnight Results: (6/3/14)-Transformation unsuccessful. Try the transformation again with Charlie’s cells and with new cells grown using iGEM’s protocol Next Steps: -Look at plates, compare cultures, etc.