Team:Concordia/Notebook/Recomb

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Recombinant Notebook

PCR parts 1-7                                                

JULY 9

Introduction: The Polymerase Chain reaction (PCR) is a technique that we employed in the lab for DNA amplification. We used Phusion DNA polymerase in our setup  because of its extremely low error rates.

Purpose:The purpose of this experiment is to PCR amplify the Gblocks that amplify properly

 

Protocol:

  1. Reaction Setup: All the reaction components were assembled before the reactions were transferred to the thermocycler. A master mix was made composed of the following reagents:

Master mix:

195uL

autoclaved H2O

60uL

5X HF buffer

6uL

dNTPs (10 mM each)

-add 43.5ul of master mix to each PCR reaction

2. In 5 50ul PCR reaction in 200ul PCR tubes for: Gene(G) 1,2,4,6 and 7

G1: P1+P2

G2: P3+P4

G4: P7+P8

   G6: P10+P11

 G7: P12+P4

32.5 uL

Autoclaved H2O

10uL

5x HF buffer

1uL

dNTPs (10 mM each)

2.5uL

Primer F (10 uM)

2.5uL

Primer R (10 uM)

1uL

template (10 ng)

0.5uL

Phusion

50uL

Total Volume

 

3. Insert the  5 PCR tubes into the Thermocycler.

Thermocycler Conditions for each Gene block

G1: P1+P2,G2: P3+P4

G4: P7+P8, G6: P10+P11

G7: P12+P4, FhuA-GBP

SOE parts 1 to 4 together and SOE parts 5-7                 

JULY 26

Introduction: Genetic recombination in which nucleotide sequences are exchanged between two similar or identical molecules of DNA. The SOE cassettes are inserted into the pYES and expressed S. cerevisiae.

Purpose: Insert SOE1-4 and SOE5-7 and express it yeast.

SOE1-4:MelA

pYES-MelA

32.5    uL  H2O

10 uL 5X GC buffer

1 uL dNTPs (10 mM each)

2.5 uL P1 (10 uM)

2.5 uL P4 (10 uM)

1 uL template G5

0.5 uL Phusion (add this last!!)

 

200 uL Final Volume

 

insert PCR tubes into thermocycler

 

PCR conditions: (ensure that the PCR lid is set to 108C to prevent evaporation)

 

98C 30 sec (initial denaturation)

98C 10 sec (denaturation) |

56 30 sec (annealing) |   x35

72C 1:20 minutes(extension) |

72 C 10 min (final extension)

12C HOLD

SOE5-7: FhuA

pYES BB_FHUA

pick colonies and resuspend in 50ul sterile water

 

Use the following reaction mix for each PCR:

-2 μl 10x Thermo polymerase buffer

-0.5 μl  dNTPs

-1.2 μl 10 μM P13 primer

-1.2 μl 10 μM P14 primer

-.2 μl Polymerase taq

-12.9 μl H2O

-2 μl template suspension

Master mix(7x)

-14 μl 10x Thermo polymerase buffer

-3.5 μl  dNTPs

-8.4 μl 10 μM P13 primer

-8.4 μl 10 μM P14 primer

-1.4 μl Polymerase taq

-90.3 μl H2O

-aliquot 18ul into each pcr tube and then add 2ul t  he corresponding template

PCR protocol

-95 C for 6 minutes (disrupt cells, separate DNA)

-Cycle 35 times:

-95 C for 30 s (melting)

-60 C for 30 s (annealing)

-72 C for 1:30 s (elongation)

-72 C for 10 minutes (final elongation)

-4 C forever

 

Colony PCR                                        

JULY 29

Introduction:  We employed a method for determining the presence or absence of abn insert DNA        

Purpose:the yeast that have undergone homologous recombination and to check if SOE 1-4 and SOE 5-7 have been integrated into pYES properly.

1.Use pipet tip to resuspend a plated colony in 15 μl sterile water.


 

2. Prepare reaction mixture

 

Reaction Mix

Use the following reaction mix for each PCR:

2 μl 10x Taq buffer

2 μl 10x dNTPs (10x = 2.5 mM each dNTP)

0.4 μl 40 μM FWD primer

0.4 μl 40 μM REV primer

0.2 μl Taq Polymerase

13 μl H2O

1.0 μl template suspension

 

PCR protocol

95 C for 6 minutes (disrupt cells, separate DNA)

Cycle 30 times:

95 C for 30 s (melting)

X C for 30 s (annealing)

72 C for X s (1min/kb) (elongation)

72 C for 10 minutes (final elongation)

4 C forever


 

Transformation of E.coli                                             

AUGUST 8

Introduction:“Competency” is the ability of a microorganism to uptake DNA from its environment. Some organisms are naturally competent. Competency can also be induced. One of the mysteries of molecular biology is how competency is induced… we know how do to it, but not quite how it works. There are two main ways to make organisms competent: high salt/heat, and electrical current. Salt/heat is easy and cheap: grow E. coli, mix with calcium salt, concentrate 20-fold. Once the cells are in calcium they are a bit fragile, so it’s important to resuspend gently.

Purpose:

Two flasks of 200 mL LB = 20 mL competent cells

Day 1

Pre-warm two 1L flasks – containing 200mL LB each – at 37°C overnight

NOTE: This isn’t necessary but decreases the time it takes for the E. coli to reach the right OD

Inoculate 5 mL DH5α in LB

For 400mL of inoculated LB, you will need:

200mL chilled 50mM CaCl2

20mL chilled 50mM CaCL2 + 15% glycerol

4 x 200mL pre-autoclaved, pre-chilled centrifuge bottles

NOTE: do NOT fill over half-full or they WILL leak!!!

 

Day 2

Inoculate DH5a 1:100 into both flasks (2mL into 200mL)

Grow to OD ~0.5 (between 0.45 and 0.55 is good)

Cool the temperature of the flasks as fast as possible: incubate the glassware in a slushy ice bath for 30 mins

Pour into 4 x 200mL pre-chilled centrifuge bottles. Balance the bottles

In pre-chilled centrifuge, spin @ 4000g for 10 mins

Decant supernatant

Resuspend each bottle in a small amount of cold 50mM CaCl2

Pool two bottles into one bottle, then complete each bottle to ~100mL 50mM CaCL2. Balance the bottles

Incubate on ice for 10 mins

In a pre-chilled centrifuge, spin @ 4000g for 10 mins

Decant supernatant; resuspend each bottle in small amount of cold 50mM CaCL2 + 15% glycerol

Pool two bottles into one 50mL Falcon tube, then fill to 20mL

Aliquot as desired

OPTIONAL: to increase transformation efficiency, snap-freeze in liquid nitrogen

Once cells are frozen, check the transformation efficiency of an aliquot

 

Colony PCR the newly transformed E coli         Aug-26-2016

 

Introduction:  We employed a method for determining the presence or absence of the transformed E.coli

1.Use pipet tip to resuspend a plated colony in 15 μl sterile water.

2. Prepare reaction mixture

 

Reaction Mix

Use the following reaction mix for each PCR:

2 μl 10x Taq buffer

2 μl 10x dNTPs (10x = 2.5 mM each dNTP)

0.4 μl 40 μM FWD primer

0.4 μl 40 μM REV primer

0.2 μl Taq Polymerase

13 μl H2O

1.0 μl template suspension

PCR protocol

95 C for 6 minutes (disrupt cells, separate DNA)

Cycle 30 times:

95 C for 30 s (melting)

X C for 30 s (annealing)

72 C for X s (1min/kb) (elongation)

72 C for 10 minutes (final elongation)

4 C forever