Astronaut DNA

Brainstorming Period:

    From the beginning of our collaboration as a team, we focused our efforts on conducting individual research to present ideas at collective brainstorming sessions. Regular meetings allowed for presenting and refining ideas, with regular peer and advisor feedback. Ideas were proposed and narrowed down until our current project was selected and team roles were assigned.

    February 4th-Feburary 8th

  • First official team meeting held.
  • Brainstorm leader selected to assign research tasks and direct meeting trajectory.
  • February 9th- February 15th:

  • Guidelines for team meetings established; presentation schedule organized.
  • Presentations given by team members to propose project ideas.
  • Workshop conducted by Wendy Way, STEM librarian at the University of Rochester on the following topics:
    • Compiling research
    • Creating visual guides
    • Analyzing primary literature

    February 16th- February 22nd:

  • Brainstorm efforts and presentations continued.
  • Initial DBTL models created for project development.
  • Team members continued to provide feedback on project ideas.
  • February 23rd- March 1st:

  • Brainstorm efforts and presentations continued.
  • Project ideas narrowed down to Top Ten proposals.
  • Top Ten ideas formally presented to advisors for feedback.
  • March 2nd- March 8th:

  • Team divided into groups to focus research efforts on the Top Ten. Research expanded to include:
    • Candidate genes, promoters, and host chassis
    • Local applications and intended impact
    • Early hardware and software concepts
  • Group deliberations on Top Ten ideas continued; general presentations regarding project development created for advisor feedback.
  • March 9th- March 15th:

  • Spring break: no team meetings held.
  • Individual research and idea development continued.
  • March 16th- March 22nd:

  • Group deliberations continued in preparation for “Top Three Ideas” meeting.
  • Ideas narrowed down upon deliberation.
  • March 23rd- March 29th:

  • Top Three Ideas meeting held; presentations given to advisors for feedback.
  • Formal project deliberations held; final project selected.
  • Leadership elections held; team roles finalized.

Preparation and Protocol Development:

    After finalizing the project idea, the team was organized into subcommittees for managing developing branches of the project as well as specific experimental modules, with a research focus on identifying key components. Experimental approaches were refined with advisor feedback and team workshops. Wet-lab protocols were developed, with associated training provided to prepare for experimental work.

    March 30- April 5th:

  • Subcommittees established:
    • Wet-Lab
    • Hardware
    • Modelling
    • Policy and Practice
  • Project divided into 4 modules:
    • Autotrophic E. coli
    • Acetate Production
    • CRISPRi
    • PHB/PHV production
  • Team divided into groups to identify BioBrick candidates for each module.
  • April 6th- April 12th:

  • Research and refining ideas for BioBricks continued, with periodic advisor feedback
  • Ideas for hardware associated with each module conceptualized and refined
  • BioBrick workshop held, reviewing the following topics:
    • BioBrick components
    • Cloning methods
    • Insert verification

    April 13th- April 19th:

  • Project revisions continued.
  • April 20th- April 26th:

  • Determination of assays for all modules began.
  • April 27th- May 3rd

  • Assay protocols refined.
  • Lab safety protocols drafted following University of Rochester Environmental Health & Safety (EH&S) guidelines
  • May 4th- May 10th

  • Final exam reading period: no team meetings held.
  • May 11th- May 17th

  • Wet-lab bootcamp attended by all team members.
    • Basic lab techniques and safety were reviewed
  • Protocols developed for experiments to be run over the summer.
  • Potential donors and sponsors contacted.

Wet Lab:

    The team began the summer by culturing bacteria, preparing plasmids, and amplifying DNA. Established wet-lab protocols were refined and optimized for future experiments.

    May 18th- May 31st

  • First overnight cultures of DH5Alpha prepared.
  • 40% Glycerol Bacterial Stocks prepared.
  • BioBricks ordered.
  • June 1st- June 7th

  • DH5Alpha and BL21 competent cells prepared.
  • Plasmid backbones miniprepped: pSB1A3, pSB1C3, pSH4C5, pSB3T5, and pRHA-113
  • Plasmids verified with restriction digest and gel electrophoresis.
  • June 8th- June 14th

  • Stock of DH5Alpha and BL21 competent cells prepared and stored.
  • Chemically competent cells transformed with miniprepped plasmids and plated on selection media.
  • June 15th- June 28th

  • PCR amplification of BioBricks began.
  • Transformations of 7 BioBrick parts into chemically competent cells performed.
  • Optimization of PCR conditions on BioBrick DNA undertaken
    • Appropriate annealing temperatures troubleshooted
    • General primers used due to high specificity of amplification

    June 29th- July 5th

  • Optimization of colony PCR conditions undertaken.
  • Diagnostic restriction digests using EcoRI and PstI performed to verify inserts
  • Troubleshooting of 3T5 backbone cloning continued.
  • July 6th- July 12th

  • PCR amplification for all parts completed and verified with gel electrophoresis.
  • Ligation reactions and transformation of parts into DH5ɑ initiated.
  • July 13th- July 19th

  • Efficiency of digestion and gel extraction optimized.
  • 50μL PCR reactions for BioBrick template continued to obtain more DNA.
  • July 20th- July 26th

  • High-fidelity restriction enzyme usage began to improve digestion efficiency.
  • Primers specific to colony PCR verification designed.
  • Workflow of digestion-ligation-transformation repeated.
  • July 27th- August 2nd

  • Initial cloning efforts continued; number of transformants for cloned biobricks increased
  • Troubleshooting of colony PCR continued; verification remained inconsistent.
  • August 3rd- August 23rd

  • Cloned parts sent to PlasmidSaurus for sequencing.
  • Attempts to identify and troubleshoot remaining colony PCR inefficiencies continued.
  • August 24th-August 30th

  • pSB3T5 backbone replaced with pSB1C3 for improved results.
  • Double digests on new constructs performed.
  • Ligation and transformation into DH5ɑ E. coli cells conducted.

Wrapping Up:

    At the beginning of September, the team focused on verifying genetic constructs and performing associated assays. Data from assays, diagnostic digests, and growth experiments were collected and analyzed to prepare for documentation and uploading to the Wiki.

    August 31st-September 6th

  • Cloned parts sent to PlasmidSaurus for sequencing.
  • Colony PCR continued.
    • Some growth of 1C3 parts verified.
  • Diagnostic digests of BioBricks continued.
  • Attempts to assemble and transform E. coli cells with BioBricks continued.
  • September 7th-September 20th

  • Troubleshooting of colony PCR continued.
  • Carbonic anhydrase and Bradford assays performed to test enzyme activity and protein concentration.
  • Subcloning for assembling constructs continued.
  • September 21st-September 27th

  • Protein assays and BioBrick transformation continued.
  • Diagnostic digests for insert verification continued.
  • September 28th-October 4th

  • Final diagnostic digests performed and gels ran for visualization of results.
  • Assays for growth and acetate production continued.
  • Growth curves for wild type E. coli strains grown in clinostat produced and analyzed.
  • All assay data and gel images compiled in preparation for Wiki upload.
  • Figure annotations and captions written in preparation for Wiki upload.
  • October 5th-October 8th

  • Final assay data collection performed and uploaded in preparation for Wiki Freeze.

Bacterial Culture

Lysogeny Broth (LB) Media Preparation
Cycle: Liquid autoclave · 90 min Final volume: 1 L

Materials

Bacto Tryptone10 g
Yeast Extract5 g
NaCl10 g
dH2O / ddH2Oto 1 L

Equipment

  • 2 L flask + magnetic stir bar
  • 1 L graduated cylinder
  • Autoclave machine
  • Magnetic stir plate

Procedure

  1. To a 2 L flask with a magnetic stir bar, add: 10 g Bacto Tryptone; 5 g Yeast Extract; 10 g NaCl.
  2. Add ddH2O to a final volume of 1 L.
  3. Mix well on a magnetic stir plate for 5–10 min until homogenous.
  4. Autoclave for 90 min on liquid cycle.
  5. After autoclaving, allow to cool to room temperature.
LB–Agar Plate Preparation

Materials

Bacto Tryptone2 g
Yeast Extract1 g
NaCl2 g
Bacto Agar2.4 g
ddH2Oto 200 mL
Selection markerper table

Equipment

  • 2 L flask + stir bar
  • 1 L graduated cylinder
  • Autoclave machine
  • Bunsen burner
  • Plastic bag + paper towel

Procedure

  1. To a 2 L flask with a magnetic stir bar, add: 2 g Bacto Tryptone; 1 g Yeast Extract; 2 g NaCl; 2.4 g Bacto Agar.
  2. Add ddH2O to a final volume of 200 mL.
  3. Mix well 5–10 min until homogenous.
  4. Autoclave for 30–60 min.
  5. Allow to cool to ~60°C after autoclaving.
  6. Add desired concentration of selection marker (see table).

Selection Marker Final Concentrations

Selection MarkerFinal Concentration
Ampicillin100 µg/mL
Tetracycline10 µg/mL
Chloramphenicol25 µg/mL
  1. Pour liquid mixture into plates next to a Bunsen burner and dry overnight.
  2. Store plates at 4°C in a plastic bag with a paper towel to absorb moisture.
Liquid Bacterial Culture Preparation

Materials

  • 5 mL Lysogeny Broth (LB)
  • Antibiotic of choice
  • Bacterial colonies

Equipment

  • 10 mL culture (Falcon) tubes
  • Gyrotory water bath shaker

Procedure

  1. Add 5 mL LB to a culture tube.
  2. Add desired antibiotic (see concentrations below).

Selection Marker Final Concentrations

Selection MarkerFinal Concentration
Ampicillin100 µg/mL
Tetracycline10 µg/mL
Chloramphenicol25 µg/mL
  1. Pick a single colony and inoculate the liquid.
  2. Incubate at 37°C overnight with shaking at 200–250 rpm.
Competent E. coli Preparation (CaCl2)

Materials

  • 100 mM CaCl2
  • LB media
  • Liquid nitrogen (for aliquot freezing)

Equipment

  • Spectrophotometer
  • 50 mL Falcon tubes
  • High-speed centrifuge

Procedure

Day 1

  1. Make 2 mL overnight liquid culture of E. coli.

Day 2

  1. Add 1 mL of culture to LB medium to a final volume of 200 mL (target OD600 = 0.3–0.5) and split into four 50 mL aliquots.
  2. Incubate on ice for 10 min.
  3. Centrifuge at 4000 × g, 5 min, 4°C; discard supernatant.
  4. Resuspend pellet in 25 mL 100 mM CaCl2.
  5. Incubate on ice for 30 min.
  6. Centrifuge at 4000 × g, 5 min, 4°C; discard supernatant. Resuspend pellets in 1 mL LB and combine cells in one tube.
  7. Incubate on ice for 60 min.
  8. Aliquot 100 µL; freeze in liquid nitrogen and store at −80°C until use.
Note: Preparing 100 mM CaCl2

11.1 g CaCl2 in 1 L H2O ≈ 0.1 mol·L−1 (Mr ≈ 110.99 g·mol−1).

M9 Minimal Media Preparation

Materials

  • 12.8 g Na2HPO4·7H2O
  • 3 g KH2PO4
  • 0.5 g NaCl
  • 2 g NH4Cl
  • 1 mL 1 M MgSO4·7H2O (optional, post-autoclave)
  • Carbon source (e.g., sugar or glycerol)
  • Amino acids (if applicable; e.g., Threonine)

Equipment

  • Erlenmeyer flask + stir bar
  • Magnetic stir plate
  • Autoclave

Procedure

  1. In a flask with a magnetic stir bar, add salts (and amino acids if applicable).
  2. Add distilled water to a final volume of 1 L.
  3. Stir 5–10 min until homogeneous.
  4. Autoclave 30–60 min.
  5. Cool to room temperature.
  6. Optional: add 1 mL 1 M MgSO4·7H2O.
  7. Add carbon source (10 mL of 20% solution per chosen carbon); mix well.
Competent E. coli Transformation

Materials

  • Competent cells
  • Plasmid DNA (miniprep)
  • LB media

Equipment

  • 1.5 mL microcentrifuge tubes
  • Gyrotory water bath shaker
  • 37°C incubator / water bath, 42°C heat-shock bath

Procedure

  1. Defrost competent cells on ice (do not warm quickly).
  2. Add 50 µL competent cells to a pre-chilled 1.5 mL tube.
  3. Add 1 µL plasmid to each tube. Negative control: add 1 µL LB.
  4. Gently flick to mix (4–6 times); place on ice for 30 min.
  5. Heat shock at 42°C for 30 s; return to ice 5 min.
  6. Add 1 mL LB to each tube.
  7. Recover 1 h at 37°C with gentle rocking.
  8. Spin at 14,000 rpm for 30 s; remove all but 50–100 µL supernatant; resuspend pellet.
  9. Plate on appropriate selective media.
Glycerol Stock Preparation

Materials

  • 750 µL 40% glycerol
  • 750 µL overnight culture
  • 6 mL ddH2O (for 40% glycerol prep)
  • Liquid nitrogen

Equipment

  • 2 mL screw-top tube / cryovial
  • Sterile inoculation loop

Procedure

  1. Combine 750 µL overnight culture + 750 µL 40% glycerol in a cryovial; gently mix.
  2. To make 40% glycerol: 4 mL 100% glycerol + 6 mL dH2O; autoclave.
  3. Flash-freeze in liquid nitrogen; store at −80°C.

Note: Subsequent freeze–thaw cycles reduce shelf life.

Recovery

  1. Using a sterile loop, scrape frozen material (do not thaw vial); streak on LB agar.
  2. Grow overnight at the appropriate temperature.
E. coli Cryopreservation

Materials

  • Liquid culture (high cell density)
  • 1 mL 1× LB with 40% glycerol
  • Liquid nitrogen (for flash-freezing)

Equipment

  • High-speed centrifuge
  • Sterile toothpicks

Procedure

  1. Grow liquid culture in LB; confirm high density (e.g., OD600 for E. coli).
  2. Pellet cells; resuspend in 1 mL 1× LB with 40% glycerol.
  3. Flash-freeze; store at −80°C.
  4. Streak cells with a sterile toothpick as needed.

DNA Extraction and Isolation

Plasmid Miniprep (QIAprep® Spin Miniprep Kit)

Materials

1–5 mL bacterial overnight culture
250 µL Buffer P1
250 µL Buffer P2
250 µL Buffer N3
500 µL Buffer PB
750 µL Buffer PE
25 µL H2O

Equipment

Tabletop & high-speed centrifuges
QIAprep 2.0 spin column
1.5 mL microcentrifuge tubes
QIAGEN collection tubes

Procedure

  1. Pellet 1–5 mL overnight culture by centrifugation >8000 rpm (≈6800 × g) for 3 min at room temperature (15–25 °C).
  2. Aspirate supernatant and resuspend pellet in 250 µL Buffer P1; transfer to a microcentrifuge tube.
  3. Add 250 µL Buffer P2; invert 4–6× until clear (≤5 min).
  4. Add 350 µL Buffer N3; invert 4–6×.
  5. Centrifuge 10 min at 13,000 rpm (≈17,900 × g).
  6. Load 800 µL supernatant onto a QIAprep column; spin 30–60 s; discard flow-through.
  7. Wash with 500 µL Buffer PB; spin 30–60 s; discard.
  8. Wash with 750 µL Buffer PE; spin 30–60 s; discard. Spin again 1 min to dry.
  9. Place column in a clean 1.5 mL tube; add 25 µL nuclease-free H2O to membrane center; wait 1 min; spin 1 min to elute.
Polymerase Chain Reaction (PCR) — Q5 High-Fidelity

Materials

Q5 2X Master Mix (NEB)
Nuclease-free water
Forward & Reverse Primers
Template DNA

Equipment

Benchtop centrifuge
Microcentrifuge tubes
Thermocycler

Procedure

  1. Set thermocycler to 98 °C.
  2. Find Tm for each template.
  3. Prepare PCR mix in a microcentrifuge tube.
Component25 µL ReactionFinal Concentration
Q5 High-Fidelity 2X Master Mix (NEB)12.5 µL1X
Forward Primer1.25 µL0.5 µM
Reverse Primer1.25 µL0.5 µM
Template DNA10 ng
Nuclease-free waterto 25 µL
  1. Aliquot 25 µL PCR MM into tubes.
  2. Prepare a negative control (replace template with water).
  3. Store PCR samples at 4 °C as needed.

Thermocycler Settings (25 µL Reaction)

StepTemperature (°C)Time
Initial Denaturation9830 s
35 Cycles9810 s
6030 s
7290 s
Final Extension725 min
Hold4

* Extension times ~30 s/500 bp; optimize per insert.

Post-PCR Checks

  1. Run 0.8–1% agarose gel; visualize bands.
  2. If single correct band: PCR cleanup → quantify.
  3. If multiple bands: gel extract the correct band → quantify.
  4. If no/faint band: try annealing gradient; repeat at 50 µL.
PCR Purification (QIAquick® PCR Purification Kit)

Materials

Buffer PB (with indicator)
750 µL Buffer PE (ethanol-diluted)
20–30 µL Buffer EB or nuclease-free water
Optional: 10 µL 3 M sodium acetate (pH 5.0)

Equipment

Benchtop centrifuge
Microcentrifuge tubes
QIAquick spin columns

Procedure

  1. Add 5× Buffer PB to 1× PCR reaction; invert 4–6×.
    • If color turns orange/violet, add 10 µL 3 M sodium acetate (pH 5.0) — should return to yellow.
  2. Load to column; spin 1 min; discard flow-through.
  3. Wash with 750 µL Buffer PE; spin 1 min; discard.
  4. Spin again 1 min to dry.
  5. Elute with 20–30 µL EB/water (wait 1 min before spin).
Colony PCR

Materials

2× DNA polymerase master mix (Taq)
10 µM forward/reverse colony primers
Nuclease-free water

Equipment

Benchtop centrifuge
Microcentrifuge & PCR tubes
Thermocycler

Procedure

  1. Master mix for 30 µL (per reaction):
    • 25 µL 2× polymerase master mix
    • 2.5 µL 10 µM forward primer
    • 2.5 µL 10 µM reverse primer
  2. In tube: 30 µL nuclease-free water + 30 µL 2× mix (final 60 µL).
  3. Touch a colony with sterile toothpick; swirl into tube.

Program

StepTemperature (°C)Time
Initial Denaturation9830 s
35 Cycles9810 s
6030 s
7290 s
Final Extension725 min
Hold4

Proceed to gel electrophoresis as needed.

Gel Electrophoresis

Materials

Agarose
~50 mL 1× TAE Buffer
Sybr Safe (e.g., 1:10,000)
1 kB DNA ladder
Parafilm

Equipment

Erlenmeyer flask
Digital scale
Microwave
Electrophoresis chamber
Gel tray & comb
Gel documentation system

Procedure

  1. Weigh agarose per expected fragment size.
For 100 mL 1× TAE Buffer
Agarose Mass (g)% AgaroseFragment Size
0.50.52 kb–50 kb
0.80.8
1.01.0400 bp–8 kb
1.51.5200 bp–3 kb
2.02.0100 bp–2 kb
  1. Microwave until dissolved; cool to 45–50 °C.
  2. Add Sybr Safe (e.g., 5 µL/50 mL); swirl.
  3. Pour gel; let solidify; remove comb and place gel in chamber.
  4. Cover with 1× TAE. Load 1 kB ladder (2 µL).
  5. Mix sample + loading dye on parafilm; load. Avoid bubbles.
  6. Run 75–120 V until dye front ~80% down gel.
  7. Image under UV/blue light.

Cloning

Vector Restriction Digestion

Materials

Miniprep plasmid DNA
Nuclease-free water
10× FastDigest Buffer
Restriction enzyme(s)

Equipment

PCR tubes

Procedure

  1. Prepare a 20 µL digestion mix:
    • Calculate vector volume from concentration (e.g., to get 1 µg from 50 ng/µL, use 20 µL).
    • Add water to 20 µL total volume with 2 µL 10× buffer and 1 µL each enzyme.
  2. Mix gently; quick spin.
  3. Incubate 37 °C for 5–15 min; heat-inactivate if applicable.
Quick CIP Treatment (New England Biolabs)

Reaction Setup

Prepare a 20 µL reaction:

ReagentAmount
DNApmol DNA ends*
rCutSmart™ 10× Buffer2 µL
Quick CIP1 µL
Nuclease-free waterto 20 µL**

* ~1 µg of a 3 kb plasmid ≈ 1 pmol ends.

** If enzymes cannot be heat-inactivated, purify DNA prior to ligation.

Procedure

  1. Incubate 37 °C for 10 min.
  2. Heat-inactivate 80 °C, 2 min.
Vector Ligation (T4 DNA Ligase)

Materials

Vector DNA
DNA insert
Nuclease-free H2O
T4 DNA Ligase
10× T4 DNA Ligase Buffer

Equipment

PCR tubes
Benchtop centrifuge
Thermocycler

Procedure

  1. For a 20 µL ligation (1:3 vector:insert molar ratio):
    • 2 µL 10× T4 Ligase Buffer*
    • 50 ng vector (≈0.020 pmol)
    • 37.5 ng insert (≈0.060 pmol)
    • Nuclease-free H2O to 19 µL
    • 1 µL T4 DNA Ligase (add last)

* Thaw/resuspend buffer at room temp (do not hand-warm).

  1. Mix gently; quick spin (avoid bubbles).
Thermocycler Program — Cohesive (Sticky) Ends
StepTemperature (°C)Time
Cycle10 ↔ 3030 s each · 71 cycles
Final6510 min
Hold10
  1. Heat-inactivate at 65 °C for 10 min.
  2. Chill on ice and transform 10 µL into 100 µL competent cells.

Assays & Polymer Handling

Carbonic Anhydrase Assay

Method

The electrometric method of Wilbur and Anderson (1948) in which the time required (in seconds) for a saturated CO2 solution to lower the pH of 0.012 M Tris⋅HCl buffer from 8.3 to 6.3 at 0°C is determined. The time without enzyme is recorded at T0; with enzyme, T.

Reagents

  • 20 mM Tris⋅HCl buffer, pH 8.3. Store in an ice bath at 0-4°C before and during use.
  • Carbon dioxide saturated water. Bubble CO2 gas through 200 ml ice cold water for 30 minutes prior to assay using sodastream (pressing button for 5 seconds for high carbonation). During saturation process, store water at 0-4°C in an ice bath.
  • Enzyme

Add 1mL of cell lysate of E. coli with recombinant carbonic anhydrase to the initial volume of Tris.

Procedure

Blank Determination: Add 3.0 ml of chilled 20 mM Tris⋅HCl buffer, pH 8.3 to a 50 ml falcon tube in ice. Maintain temperature at 0-4°C and record pH.
Add 2 ml of chilled CO2 saturated water to the Tris buffer. Immediately start a stop watch and record the time required for the pH to drop from 8.3 to 6.3. Record this time as T0.

Enzyme Determination: Add 2.0 ml of chilled 20 mM Tris⋅HCl buffer, pH 8.3 to a 50 ml falcon tube on ice. Maintain temperature at 0-4°C and record pH. Add 1 ml of enzyme sample and allow for pH to equilibrate. Quickly add 2 ml of CO2 saturated water and record the time required for the pH to drop from 8.3 to 6.3. Record this time as T.

Calculations:

https://www.worthington-biochem.com/products/carbonic-anhydrase/assay

Polymer Purification and Recovery Method

MeCN (or DCM/THF) → Cold MeOH/EtOH

Lysate Cells and Weigh -
Lyse cells (via sonication or an alternative method) and weigh 10 grams of the resulting cell lysate–Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) granule mixture.

Dissolve (5–10% w/v) -
Add 100 mL acetonitrile to a beaker (for 10g PHBV)
Add 10 grams of lysate + plastic granule mix; stir at RT until fully dissolved (30–120 min).
Gentle warming to 30–35 °C can speed up; do not exceed solvent bp. Acetonitrile boils at 170ish, you can pump up the temp to much greater than 35 just a couple tens of degrees lower than the boiling point. keep in mind the melting point of pla as well, you don’t want to exceed that.

Prepare Nonsolvent Bath -
In a chilled beaker with a stir bar, add 500 mL of cold methanol. Place in an ice bath; aim for ~4–10 °C.

Precipitate (Slow Addition) -
With vigorous stirring, pour the PHBV solution slowly into the cold methanol (not the reverse). A white flocculent precipitate forms immediately. Rinse the solution vessel with a few mL of MeCN and add dropwise to maximize yield.

Collect & Wash - Vacuum filter through a Büchner funnel. Wash cake with 2× 50 mL cold MeOH to strip residual solvent.

Dry - Air-dry the cake in the hood 30–60 min, then vacuum-dry at 30–40 °C to constant mass. Gently crumble any soft agglomerates with a spatula to obtain free-flowing powder.

Source: team wiki notes. :contentReference[oaicite:0]{index=0}

One-Page SDS–PAGE + Fairbanks Staining

1) Make 5% βME Laemmli buffer (per sample, 20 µL)
10 µL 2× Laemmli (no βME)
9 µL H₂O
1 µL β-mercaptoethanol (βME) → 5% v/v
For n samples, make (n+1)× master mix (20 µL per sample).

2) Denature samples (final 1× Laemmli)
Thaw samples briefly at 23 °C, then place on ice.
Mix 20 µL 5% βME Laemmli + 20 µL protein sample (lysate supernatant).
Cap tightly; quick vortex + spin.
Heat 95 °C, 10 min.
Spin 1000 g, 5 min. Keep on ice.

3) Set up gel/tank (4–20% SDS–PAGE)
Remove bottom tape; place gel in holder.
If single gel, insert back plate.
Fill inner chamber with 1× TGS; fill outer tank to ~¼ height.
Remove comb straight up.
Rinse wells with ~15 µL 1× TGS each.

4) Load & run
Load 5 µL prestained ladder.
Load 10 µL denatured supernatant per sample.
Run 100 V, 10 min (stacking).
Then 130 V until dye front ~⅔ down gel (~50–60 min).
Do not run off the gel.

5) Retrieve gel
Open cassette; transfer gel to a staining container.

6) Fairbanks staining (A → B → C → D; 100–150 mL each)
For each solution (A, then B, then C, then D):
Submerge gel in 100–150 mL solution.
Microwave 80–90 s until just boiling.
Immediately move to fume hood; rock gently 1 min to cool.
Drain and rinse gel with ddH₂O.

7) Image
Place gel on white screen/plate in the imager.
Select Coomassie Blue program; adjust sliders for clarity.
Save images (e.g., PNG/JPG) and archive a .tif copy.

Fairbanks recipes (1 L each)
A: 0.05% Coomassie (50 mL of 1%), 25% isopropanol (250 mL), 10% acetic acid (100 mL), ddH₂O to 1 L (~600 mL).
B: 0.005% Coomassie (5 mL of 1%), 10% isopropanol (100 mL), 10% acetic acid (100 mL), ddH₂O to 1 L (~795 mL).
C: 0.002% Coomassie (2 mL of 1%), 10% acetic acid (100 mL), ddH₂O to 1 L (~898 mL).
D: 10% acetic acid (100 mL), ddH₂O to 1 L (~900 mL).

Source: team wiki notes. :contentReference[oaicite:1]{index=1}

Coomassie Plus (Bradford) Protein Assay – Quick Protocol

A) Prep: Reagent & Standards

Equilibrate & mix reagent
Gently invert the Coomassie Plus (Bradford) Assay Reagent a few times (do not shake). Bring to room temp before use.

Prepare protein standards (BSA recommended)
Use BSA 2.0 mg/mL stock to make a standard curve spanning your working range.

Standard working ranges:
Plate / test-tube (standard): 100–1500 μg/mL (linear with BSA ~125–1000 μg/mL).
Low-range (micro format): 1–25 μg/mL.

Example dilutions are provided below (use the same diluent as your samples).

Example BSA standards (standard range, for plate or test tube)
2000, 1500, 1000, 750, 500, 250, 125, 25, 0 μg/mL

Example BSA standards (low-range, for micro format)
25, 20, 15, 10, 5, 2.5, 0 μg/mL

Add 50 μL standard or sample to labeled tubes.
Add 1.5 mL Bradford reagent, mix well.
Zero spectrophotometer with water; read A595.
Blank-correct and quantify from the standard curve (linear range with BSA ~125–1000 μg/mL).

ThermoFisher user guide (for reference): MAN0011344

Rocket