Methanotroph-derived bacteriohopanepolyol signatures in sediments covering Miocene brown coal deposits

This paper is available Open Acess via the journal website.

When I joined Manchester Metropolitan University in 2016, I was awarded a small grant to set up an analysis facility measuring a group of molecular biomarkers, bacteriohopanepolyols (BHPs), that are found in environments throughout the world. This paper is the first to be published on BHPs measured at Manchester Met.

Cores of polish lignite used in this study

In this paper, led by Anna Pytlak, samples from two Polish lignite deposits were analysed via LC-MS to see which BHPs were present in the samples, and whether these could be linked to methane-generating bacterial living in the rocks now, or millions of years ago.

My role, along with PhD student Saule Akhmetkaliyeva, was to extract the BHP biomarkers from the sediment samples and analyse them on the time-of-flight mass spectrometer at Manchester Met. The molecules found in the mass spectrometer were compared against known BHP results, and identified as being from various types of bacteria. This included both Type I and Type II methanotrophs (bacteria that consume methane), including some living methanotrophs.

BHP concentrations were higher in the lignite than the surrounding mineral soil, suggesting some form of active bacterial commuity supported by the lignite deposits that cannot be sustained in regular soil. Living methanotrophs means that there’s a chance some of the methane released over time by the lignite is eaten by the bacteria and not released to the atmosphere.

If you would like to measure BHPs in your own samples, please get in touch to discuss collaborations!