There is an interesting and potentially very useful paper just out:
A brief summary from the journal:
This protocol enables collection of airborne particulate matter; and after sample pretreatment, it allows sufficient quantities of microbial DNA to be extracted and prepared for downstream applications such as metagenomic sequencing.
And the abstract:
Metagenomic sequencing has been widely used for the study of microbial communities from various environments such as soil, ocean, sediment and fresh water. nonetheless, metagenomic sequencing of microbial communities in the air remains technically challenging, partly owing to the limited mass of collectable atmospheric particulate matter and the low biological content it contains. Here we present an optimized protocol for extracting up to tens of nanograms of airborne microbial genomic Dna from collected particulate matter. With an improved sequencing library preparation protocol, this quantity is sufficient for downstream applications, such as metagenomic sequencing for sampling various genes from the airborne microbial community. the described protocol takes ~12 h of bench time over 2—3 d, and it can be performed with standard molecular biology equipment in the laboratory. a modified version of this protocol may also be used for genomic Dna extraction from other environmental samples of limited mass or low biological content.
The paper has a detailed step by step instruction guide for doing the work. Really really detailed. Sounds pretty cool right? And possibly very useful to people working on airborne microbes.
The only problem – and it is a big one to me – it is a Closed Access paper and it is in a journal that not so many subscribe to – Nature Protocols.
I am going to contact the authors to see if I can get them to post a copy of the paper or a preprint somewhere in the hopes that that will allow everyone access to it.