dna extraction from soil - (Mar/14/2005 )

I am extracting dna from soil. But the main problem I am facing is the presence of humic acid. I can't get rid of it. And I am getting negligible amount of dna. Can anyone please let me know a complete protocol (that has already been proven to work) for extracting dna from soil?

We're getting the same thing started in my lab too. Check out MoBio.com. They have some kits that they say completely eliminates humic acid. We haven't used this kit, but another we've talked to uses it and recommended it to us.

You wouldn't by any chance be doing a bacterial diversity survey would you?

Thanks Hallm. I am doing bacterial diversity survey. I am working on hypersaline environment.

I am starting up a study in water samples in the next couple weeks (everything is ordered right now), and I've never done it before. I'm an undergrad that goes to a smaller school and we don't have any current research of this type. I wanted to start some molecular biology research and so did one of the professors here, but I may have bitten off more than I can chew with this project. I've done two summers of molecular biology research at medical institutions and have done most of the techniques that a project like this requires (PCR, cloning, etc), just never this exact project from start to finish.

How is the project going? Are there any major areas of unforseen trouble? Also, what primers do you use? I've found several that have been published, but have you found one that works better than the others? Last question, about how long does it take you and your lab to go from the original DNA extraction to the last cloned colony being sequenced? Thanks for any help.

My lab-mates are working on diversity of soil bacteria for years. But I am new in this field.