Projects per year
Abstract
The compatible solute Dimethylsulfoniopropionate (DMSP), made by many marine organisms, is one of Earth’s most abundant organosulfur molecules. Many marine bacteria import DMSP and can degrade it as a source of carbon and/or sulfur via DMSP cleavage or DMSP demethylation pathways, which can generate the climate active gases dimethyl sulfide (DMS) or methanthiol (MeSH), respectively. Here we used culture-dependent and -independent methods to study bacteria catabolising DMSP in East China Sea (ECS). Of bacterial isolates, 42.11% showed DMSP-dependent DMS (Ddd+) activity, and 12.28% produced detectable levels of MeSH. Interestingly, although most Ddd+ isolates were Alphaproteobacteria (mainly Roseobacters), many gram-positive Actinobacteria were also shown to cleave DMSP producing DMS. The mechanism by which these Actinobacteria cleave DMSP is unknown, since no known functional ddd genes have been identified in genome sequences of Ddd+ Microbacterium and Agrococcus isolates or in any other sequenced Actinobacteria genomes. Gene probes to the DMSP demethylation gene dmdA and the DMSP lyase gene dddP demonstrated that these DMSP-degrading genes are abundant and widely distributed in ECS seawaters. dmdA was present in relatively high proportions in both surface (19.53% ± 6.70%) and bottom seawater bacteria (16.00% ± 8.73%). In contrast, dddP abundance positively correlated with chlorophyll a, and gradually decreased with the distance from land, which implies that the bacterial DMSP lyase gene dddP might be from bacterial groups that closely associate with phytoplankton. Bacterial community analysis showed positive correlations between Rhodobacteraceae abundance and concentrations of DMS and DMSP, further confirming the link between this abundant bacterial class and the environmental DMSP cycling.
Original language | English |
---|---|
Article number | 3206 |
Journal | Frontiers in Microbiology |
Volume | 9 |
DOIs | |
Publication status | Published - 21 Dec 2018 |
Keywords
- DMSP lyase
- Bacteria
- DMSP cycling
Profiles
-
Jonathan Todd
- School of Biological Sciences - Professor of Environmental Microbiology
- Molecular Microbiology - Member
Person: Research Group Member, Academic, Teaching & Research
Projects
- 2 Finished
-
A multidisciplinary study of DMSP production and lysis - from enzymes to organisms to process modelling.
Todd, J., Airs, R., Beale, R., Hopkins, F., Le Brun, N., Malin, G., Polimene, L., Pratscher, J., Tarran, G. & Green, R.
Natural Environment Research Council
1/05/17 → 30/04/22
Project: Research
-
Bacteria make DMSP - how significant is this process?
Todd, J., Murrell, C., Pratscher, J. & Curson, A.
Natural Environment Research Council
17/01/16 → 16/01/19
Project: Research