Is thiosulfate an important energy source for marine bacterioplankton?

Bacteria in the water column are known as bacterioplankton and have several important functional roles in marine ecosystems. Bacterioplankton are a major proportion of the standing stock of biomass and are responsible for the recycling of organic carbon produced by phytoplankton. Bacterioplankton are the basis of the marine food chain and are responsible for most biogeochemical processes.

Our understanding of the diversity of bacterioplankton has been greatly enhanced through the application of molecular techniques, such as genome sequencing. The sequencing of numerous bacterioplankton genomes has revealed that many are capable of using thiosulfate, a marine sulfur compound, as a supplementary energy source. This means that those bacterioplankton that use thiosulfate could grow faster and more efficiently.

This research will determine if thiosulfate is a feasible supplementary energy source for marine bacterioplankton. A preliminary assessment of thiosulfate concentrations and thiosulfate utilisation gene activity will be made at an established coastal sampling station in the English Channel. This information will be used to design laboratory experiments using a model bacterioplankton. The laboratory experiments will determine the physiological and metabolic effects of thiosulfate under natural conditions.

This research will improve our understanding of how the bacterioplankton function. The knowledge will be valuable to other marine scientists interested in biogeochemical cycling, especially the carbon cycle. The data will also be useful to scientists sequencing marine bacterial genomes because it validates their observations of prevalent thiosulfate utilisation genes.

Schools and General Public:
As part of the British Science Association's National Science and Engineering Week, the MBA has run interactive workshops for the past 11 years. The two day event at the MBA is called "Marine Biologist for a Day" and attracts 120+ students aged between 9 and 18 from around the country with a keen interest in Marine Biology. Participants are given a unique opportunity to learn about scientific techniques in a hands-on interactive way and to meet scientists and learn about potential career opportunities. Whilst subjects relevant to the science curriculum are covered, the event is aimed at stretching the knowledge of students and developing scientific knowledge further.

The knowledge created in this research proposal will be detailed and mechanistic; it is therefore unlikely to be directly applicable to school pupils or the general public. The general themes and conclusions of this research, such as the links between diversity and ecosystem functioning, could however be of value to these groups in an appropriate format. These general themes are now frequently communicated in the media (e.g. BBC Frozen Planet series). In its broadest sense, the knowledge created from this proposal could contribute to the general public's increasing awareness of the complex interactions which define marine ecosystems.

Membership of the Marine Biological Association Learned Society:
The membership of the Marine Biological Association Learned Society includes Marine Science professionals and the wider public with an active interested in Marine Biology. The Learned Society has more than 1,000 members world-wide.

This user group could value the knowledge gained if delivered in an assessable and easy to read science style that examines the role of microbial diversity in maintaining biogeochemical processes.

Marine Biodiversity and Policy Groups:
The UK State of Seas Report (Charting Progress 2) was the first to explicitly include information on microbial processes, including the role of bacteria in the oceans. The Healthy and Biologically Diverse Seas Evidence Group (HBDSEG) is part of the UK government strategy for ocean monitoring (UK Marine Monitoring and Assessment Strategy (UKMMAS)) and produced the biological sections of the Charting Progress report. The MBA is a member of the HBDSEG committee.

HBDSEG is seeking a greater understanding of microbial processes in order to inform high level political drivers such as the Marine Strategy Framework Directive (MSFD). Understanding healthy ecosystem functioning is vital when considering indicators and monitoring for Good Environmental Status (GES) which will need to be achieved under MSFD. Research knowledge will be supplied directly to the new working groups set up to carry work forward on the MSFD.

The Marine Climate Change Impacts Partnership (MCCIP) is a partnership between scientists, government, its agencies, nongovernmental organisations (NGOs) and industry. The principal aim is to provide a coordinating framework for the UK, so as to be able to transfer high quality evidence on marine climate change impacts, and guidance on adaptation and related advice, to policy advisers and decision makers. The MBA has a leading role in MCCIP and currently chairs its working group. The MCCIP Annual Report Card provides the very latest updates on how climate change is affecting our seas. Almost 100 scientists from 40 leading UK science organisations contributed to this report card, making it our most comprehensive to date. The Report Card is produced for and delivered directly to a wide range of policy customers and stakeholders.

The research proposed will delivery new knowledge of the coastal sea carbon cycle and is linked to understanding climate change. It will therefore form part of the information submitted to the MCCIP from the MBA for the 2014 Report Card.