Laccase Protocols: Difference between revisions
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===Notes=== | ===Notes=== | ||
===References=== | ===References=== | ||
*Soden et al. (2002) Molecular cloning of a laccase isozyme gene from Pleurotus sajor-caju and expression in the heterologous Pichia pastoris host. Microbiology 148 (2002), 4003-4014 | *Soden et al. (2002) '''Molecular cloning of a laccase isozyme gene from Pleurotus sajor-caju and expression in the heterologous Pichia pastoris host'''. ''Microbiology'' 148 (2002), 4003-4014 | ||
==DMP Assay== | ==DMP Assay== |
Revision as of 11:18, 6 October 2011
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Introduction
This protocols are used to screent for and assay laccase activity.
Bromophenol Blue Plate Screen
Materials
Bromophenol blue
Procedure
Notes
References
Guiacol Colony Screen
Materials
- Gum Guiac or Guiacol
- 95% Ethanol
Procedure
1. Dissolve either 17mg gum guaiac or 13mg guaiacol into 1ml of 100% ethanol.
- If your guaiacol is in liquid form then add 12μL to 1ml ethanol.
2. Drop one drops of this solution on a large colony (2 days old for bacteria).
3. Wait four hours and a laccase positive colony should turn purple.
4. Bacteria don't usually like ethanol, so now they're probably dead.
Notes
References
Lignin Plate Screen
Materials
- Alkaline Lignin
- Ferric Chloride
- Potassium ferric cyanide
- Apropriate agar growth medium
Procedure
Notes
References
ABTS Assay
Materials
- ABTS 20mM (10mg/mL) stock solution
- CuSO4 100mM (25mg/mL) stock solution
Procedure
1. Make a liter of your favorite agar growth medium and autoclave.
2. After cooling to 65°C add:
- 10ml/ABTS (0.2 mM)
- 1mL CuSO4
3. Swirl to mix and pour plates.
4. Once plates are hard:
- Drop 5μL of overnight culture onto the plate (when this dries it will form a little circle).
- Culture plate 24-48 hours
- Observe green halos around ABTS oxidizing cultures.
Notes
References
- Soden et al. (2002) Molecular cloning of a laccase isozyme gene from Pleurotus sajor-caju and expression in the heterologous Pichia pastoris host. Microbiology 148 (2002), 4003-4014
DMP Assay
Materials
- DMP (2,6-dimethoxyphenol)
- DMS (2,2 dimethyl succinate)
Procedure
1. Prepare substrate solution:
- 4mM DMP (620mg/L)
- 200mM DMS (29.2g/L)
2. Centrifuge 1ml of overnight culture.
3. Place 750μL of cleared supernatant in a microcentrifuge tube.
4. Add 250μL of substrate solution.
5. Incubate for 10 minutes.
6. Measure absorbance at 468nm every minute.
- An increae in absorbance is positive for laccase activity.
- Extinction coefficienct = = 49.6 AU/mM*cm
Notes
References
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