Getting a handle on the genome: the development and application of enzymatic, sequence-specific DNA alkylation
Dr. Robert K. Neely, University of Birmingham, UK
Our work focusses on the application of enzymes as molecular machines that can deliver targeted modifications to the DNA molecule. We apply this chemistry as a tool for microscopy and for sorting of genomic populations.
The DNA methyltransferases direct sequence-specific DNA methylation to short sequences, typically between 2 and 6 base pairs in length. The source of the methyl-group in these methylation reactions is the ubiquitous cofactor S-adenosyl-L-methionine (AdoMet). We synthesise a range of AdoMet analogues that turn the methyltransferases into alkyltransferases, capable of covalent DNA modification with extended functional groups.
In this talk, I will share recent work on the fluorescent labelling of DNA using the M.TaqI enzyme to produce single-molecule DNA barcodes that can be used to identify bacteria in complex mixtures of DNA. Using this approach we are able to capture images of several gigabases of DNA within 30 minutes. Recent work has focussed on the analysis of these vast datasets, a problem which has parallels in image recognition of the type used in search engines and facial recognition. I’ll share recent efforts that show promise for the development of a robust approach for the rapid identification of pathogenic species using our DNA barcodes.
Other work in my lab is investigating the use of this technology to sort methylated- from unmethylated DNA for genomic analyses. I will share promising recent results that indicate effective and efficient sorting using the MpeI DNA methyltransferase enzyme.