Monday, August 31, 2009

Developments in Anti-Smiling Technology

-- IMMEDIATE LINK TO GUIDE --

-- LINK TO DGGE BOOK CHAPTER --


Dear DGGE users -

There is a new product from Ingeny to reduce and/or prevent smiling for DGGE gels. For the Ingeny system, the product is both a new spacer and a special loading solution for the first and last lanes. Information regarding these items can be found here.
I spoke with Ingeny, and they are intending to make spacers for other DGGE systems.
The loading solution alone is not effective.

Looks like a nice breakthrough.

Best,
Stefan

Friday, July 24, 2009

DGGE Book Chapter

Dear Friends -

While it may seem that I haven't posted much lately, I have still been working on DGGE-related matters. Together with my colleagues Mary Beth Leigh and Josh Neufeld, I have written a book chapter entitled "Denaturing gradient gel electrophoresis (DGGE) for microbial community analysis". It has some background on the method, as well as detailed protocols for producing gels, primer sets for bacterial, archaeal and fungal community analysis, a list of all required reagents, comparison of three major DGGE makers, and troubleshooting. If this chapter is useful to you, please cite the following:

Green, S.J., Leigh, M.B. and Neufeld, J.D. 2009. Denaturing gradient gel electrophoresis (DGGE) for microbial community analysis. Pages 4137-4158 in: Timmis, K.N. (Ed) Microbiology of Hydrocarbons, Oils, Lipids, and Derived Compounds. Springer (Heidelberg, Germany).

Currently, the chapter is available for download. There may be some slight differences between this and the final typeset chapter, but this should be marginal.

Cheers,
Stefan

Thursday, October 16, 2008

SB buffer for DGGE?

I recently received this question:
Hi Stefan,
I am new to this blog and stumbled upon it. Have you used the SB buffer in the DGGE apparatus? If so what have your run times and concentrations been? I have been using SB buffer with standard agarose gels but I am still using TAE buffer in our DGGE set up at 150V for 10h. Just curious and interested in saving some time.
Dusty

-- My response:
No, I haven't tried it. I am now in a lab without a DGGE, so I haven't had a chance. Theoretically, it should work and it should significantly reduce the cost of making buffer. I doubt it will make a big difference in the running time, because the limitation on voltage in a DGGE doesn't have much to do with the gel heating up (as in agarose gel electrophoresis).

Some thoughts - make sure to use SB buffer when making the acrylamide stock solutions. If you (or anyone else) tries SB buffer in place of TAE, please email me about the results and I'll post it.

Cheers,
Stefan

P.s. I have received the following comment from Michael (see below). His response would indicate that SB buffer is NOT appropriate for DGGE. C'est la vie.

"In fact I also have quite bad experience with SB buffer. Apart from the worse separation, it seems that SB somehow modifies gel's structure, making it softer and more fragile. Moreover, gels submerged into the staining solution significantly increase their dimensions, which suggests some kind of inhibition of the poliacrylamide polimerisation."

Friday, August 01, 2008

New NCBI BLAST function for primer design

I thought this would be of interest to the community. The BLAST site at NCBI now has a specific page for the design and testing of PCR primers (click here). It looks to be quite sophisticated if necessary (there is a pull down menu for more advanced options).

http://www.ncbi.nlm.nih.gov/tools/primer-blast/index.cgi?LINK_LOC=BlastHomeAd

Thursday, May 08, 2008

DGGE standards

- IMMEDIATE LINK TO GUIDE -

A message at the Yahoo DGGE group indicates that a company in Japan (Nippon Gene Co., LTD.)is selling DGGE markers for a variety of different gradient conditions. I tracked down the website, and although most of the text is in Japanese, it is still fairly easy to figure out what products are what. Anyway, I'm including a link to the standards page. And, as always - I am not affiliated with this company in any way! Caveat emptor. And remember - you can always make your own standards if you put your mind to it.

Cheers,
Stefan

Tuesday, May 06, 2008

Cyanobacterial Article Available for Free, Online at ISME Journal

- IMMEDIATE LINK TO GUIDE -

Ok, my cyanobacterial article - "A salinity and sulfate manipulation of hypersaline microbial mats reveals stasis in the cyanobacterial community structure" is a featured (and therefore freely accessible) article in the current issue of the ISME Journal.
Enjoy.

Cheers,
Stefan

Wednesday, April 30, 2008

Post-doctoral position in Israel available

- IMMEDIATE LINK TO GUIDE -

Ok, this isn't strictly a DGGE issue, but you might get to use DGGE....!

If anyone is interested in pursuing a post-doctoral position in microbial ecology, I can highly recommend the following project, sponsored by several excellent scientists in Israel.

The project is a cooperation between the Israel's police Division of Identification and Forensic Science, the Minz Laboratory, the Gillor Laboratory and the Jurkevitch Laboratory.

The goal of the project is to develop a forensic tool for the analysis of soil samples using bacterial communities fingerprints. The post-doc fellow will be in charge of developing, applying and validating protocols for soil analysis using molecular markers, analyzing large numbers of samples, and building an adequate integrative approach for sample correlation. He/she will coordinate the work of students and technicians of the various groups. The research requires skills in molecular microbial ecology, bioinformatics and statistical analysis and biochemistry.

If interested, please contact: Prof. Edouard Jurkevitch (jurkevi@agri.huji.ac.il), Dr. Osnat Gillor (gilloro@bgu.ac.il) or Dr. Dror Minz (minz@agri.gov.il).