DNA Extraction from 0.22 μM Sterivex Filters and Cesium Chloride Density Gradient Centrifugation
Summary
We describe a method for extraction of high molecular weight genomic DNA from planktonic biomass concentrated on 0.22 μm Sterivex filters, followed by cesium chloride density gradient centrifugation for purification.
Abstract
Protocol
Discussion
Depending on how many samples are to be processed, this can be a time-intensive procedure due to the two one-hour incubation steps, and the repeated washes and centrifugation steps. It is best to plan two whole days for this procedure to leave plenty of time. If there are problems getting the final extract volume in the Amicon tube to reduce down to 200-500μl during DNA concentration and washing, try doing additional TE washes and centrifugations (repeat Part Three) until the appropriate volume is leftover. Also, i…
Acknowledgements
We would like to thank the Canadian Foundation for Innovation, the British Columbia Knowledge Development Fund and the National Sciences and Engineering Research Council (NSERC) of Canada for supporting ongoing studies on low oxygen regions of coastal and open ocean waters. J.J.W. was supported by fellowships from NSERC and D.A.W. was supported by fellowships from NSERC, Killam and the TULA foundation funded Centre for Microbial Diversity and Evolution. S.L. was supported by the TULA foundation funded Centre for Microbial Diversity and Evolution.
Materials
| Material Name | Type | Company | Catalogue Number | Comment |
|---|---|---|---|---|
| 1 cc syringe (26G5/8 needle) | BD | 309597 | ||
| 1 ml syringe (26G5/8 needle) | BD | 309597 | ||
| 1.5ml eppendorf tubes | Eppendorf | 0030 125.150 | ||
| 15ml tubes | Sigma | CLS430791 | ||
| 5cc syringe | BD | 309603 | ||
| Amicon® Ultra-4 Centrifugal Filter Devices | Millipore | UFC801096 | 10,000 Nominal molecular weight limit | |
| Butanol | Fisher | A383-1 | Make it water saturated (butanol:water = 1:1) | |
| Centrifuge rotor, JA5.3 | Beckman Coulter | 368690 | ||
| Centrifuge, Avanti® J-E | Beckman Coulter | 369003 | ||
| Cesium chloride | Sigma | C4036 | ||
| Chloroform:IAA (24:1) | Sigma | 25666-500ML | ||
| Ethidium Bromide (EtBr) | Sigma | E1510-10ml | ||
| Ethylenediaminetetraacetic acid disodium salt dihydrate | Sigma | E5134 | ||
| Hybridization oven | Fisher Scientific | 13-247-10 | 37°C & 55°C | |
| Lysis Buffer | 0.75 M sucrose, 40 mM EDTA, 50 mM Tris (pH 8.3) | |||
| Lysozyme | Sigma | L6876-5G | 125 mg in 1000 μl TE | |
| Microcon® Ultracel YM-30 Centrifugal Filter Unit | Millipore | 42410 | 50 bp cut off | |
| Parafilm | Fisher | 13-374-10 | ||
| Phenol:Chloroform:IAA (25:24:1) | Sigma | 77617-500ML | ||
| Proteinase K | Qiagen | 19133 | ||
| RNase A | Fisher | BP2539-100 | 10 μg/ml | |
| Safe Imager™ Blue light transilluminator | Invitrogen | S37102 | ||
| Sodium Dodecyl Sulfate (SDS) | Sigma | L4509 | 20% SDS | |
| Sterivex filters | Fisher | SVG010RS | ||
| Sucrose | Sigma | S0389 | ||
| Table top centrifuge | Eppendorf | 5415D | ||
| TE buffer, pH 8.0 | ||||
| Trizma® base | Sigma | T1503 | ||
| Ultracentrifuge rotor, TLA 100 | Beckman Coulter | 343847 | ||
| Ultracentrifuge tube (7X20mm, PC) | Beckman | 343775 | ||
| Ultracentrifuge tube rack | Beckman | 348302 | ||
| Ultracentrifuge, Optima® Max | Beckman Coulter |
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