Fungal Genomic DNA Extraction Methods for Rapid Genotyping and Genome Sequencing

Abstract

Isolation of fungal genomic DNA of high quality is required for a number of downstream biotechnology-derived applications such as genome sequencing, microarrays, and digital PCR technologies, to only name a few. In most cases, not only a high molecular weight DNA of superior grade is required but also large quantities. On the other hand, a number of laboratory experiments, such as polymerase chain reaction (PCR) for medical diagnostic or for genotyping, have to be conducted in a limited amount of time and can provide complete results with the use of lower quality DNA. We describe here two different fungal DNA extraction approaches, which are applicable to a wide range of fungal species.

First, we adapted a DNA extraction method for PCR-based genotyping which allows analysis of single to hundreds of colonies simultaneously. Cells are disrupted in the presence of sodium dodecyl sulfate and Proteinase K which are then removed by precipitation and centrifugation. The cleared lysate is used for PCR reaction.

Secondly, we describe a method to obtain genome sequencing quality grade DNA from fungal liquid cultures. Mycelia are harvested by either filtration or centrifugation. Cells are mechanically disrupted by liquid nitrogen grinding, followed by genomic DNA extraction using the QIAGEN’s DNeasy^® Plant Kit. The quality and quantity of genomic DNA is monitored by fluorometry.