Abstract
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.
United Kingdom