Topography of microbial assemblages
Lead Research Organisation:
Plymouth Marine Laboratory
Department Name: Plymouth Marine Lab
Abstract
Microorganisms are everywhere and they are fundamentally important. They were the earliest form of life on the planet and have been around for 3.7 billion years; indeed for the first 2 billion years, bacteria were the only living things on the planet. Their activity changed the planet, changing the environment to allow other life forms to develop. Today, bacteria continue to be very important for the health of the global ecosystem since they are involved in and control all biogeochemical cycles. For such an important group, it is perhaps surprising how little we know about bacteria and archaea (another group of important prokaryotic microbes). This is partly because they are difficult to study, particularly in the natural environment. Classical approaches that involve growing bacteria in the laboratory do not work because more than 99% of bacteria cannot grow in standard microbiological media. But in recent years, considerable progress has been made in identifying the diversity of microbes in the natural environment. Genetic and metagenomic approaches have given us great insight into which organisms are present and, increasingly, the function of these organisms. However, these techniques operate at the level of the community and we still know almost nothing about the individuals that make up that community / and particularly how they interact. This proposal tackles two problems that have limited understanding of bacteria from the natural environment / how to manipulate such small organisms in a defined way and how to identify different 'species'. Using state-of-the-art technology, we will encapsulate bacteria from natural assemblages (both marine and soil environments) so that they can be manipulated. We will use a novel microscope to distinguish between different bacterial species. Using a combination of these two techniques, we will investigate how different bacterial species interact, either through supplying nutrients to each other or controlling the activity of the whole population through cell-to-cell signalling.
Organisations
Publications
Huang WE
(2009)
Raman tweezers sorting of single microbial cells.
in Environmental microbiology reports
Read DS And Whiteley AJ
(2011)
Stable Isotope Probing and Related Techniques
Read, D.S. And Whiteley A.S.
(2011)
Environmental Microbiology: Current Technology and Water Applications
Tait K
(2013)
Investigating a possible role for the bacterial signal molecules N-acylhomoserine lactones in Balanus improvisus cyprid settlement.
in Molecular ecology
Wharfe ES
(2010)
Fourier transform infrared spectroscopy as a metabolite fingerprinting tool for monitoring the phenotypic changes in complex bacterial communities capable of degrading phenol.
in Environmental microbiology
Description | The aim of this research was to use the novel technologies of microencapsulation and Raman microspectroscopy to understand factors that control the spatial development of both soil and marine microbial populations. Mechanisms with strong potential for beneficial interaction investigated were ammonia oxidising consortia, and the process of quorum sensing (QS); the interaction of microbes using cell-to-cell signal molecules. Micro-encapsulation of natural marine communities within agarose beads in conjunction with in depth sequencing was used to trace the response of a microbial community to ammonia enrichment. Significant changes in the taxonomic content of the originally sampled marine community; i.e. we successfully selected for and established a mixed community with each species developing individually within the micro-encapsules. New QS signal molecule producing genera were identified, including those associated with previously unrecognised to produce signal molecules of the class N-acylhomoserine lactones (AHLs): the Bacteroidetes. The analytical power of Raman microspectroscopy was used to develop novel approaches to study interactions between these AHL-producing microbes at the individual and community level and a Raman spectral biomolecule database was constructed. To elucidate the ecological role of AHL production and signalling interactions amongst microbes using other means, signal defective variants of two Rhodobactereceae (microbes abundant within marine communities) were constructed: the first through transposon mutagenesis of the AHL synthase and the second by transformation with an AHL degrading protein. Comparisons of the signal-producing and signal-deficient phenotype revealed an important role for AHL production in aggregation and chemotaxis. Thus, within marine systems AHLs may be used for diffusion sensing rather than quorum sensing. |
Exploitation Route | It will be most useful for other academics such as microbial ecologists: this is one of the few studies that has attempted to dissect out and reassemble microbial communities. |
Sectors | Agriculture Food and Drink Education Environment |
Description | A range of journal papers and book chapters have been published, and the data presented at conferences. The data has also been used to attract further funding. A NERC Technolgy Proof of Concept grant (Next Generation Stable Isotope Probing Technologies) was awarded to AS Whitely and DS Read to further develop this methodology (2010 - 2011). In addition, a NBAF pilot scheme grant was awarded to Dr K Tait to further study the role of AHL signal molecule production using a signal-deficient variant of a common marine bacterium (Sulfitobacter sp.) created during this project (2013). |
First Year Of Impact | 2010 |
Sector | Agriculture, Food and Drink,Education,Environment |
Description | A study of processes under quorum sensing control in the marine bacterium Sulfitobacter sp. |
Amount | £4,800 (GBP) |
Funding ID | NEBC-NBAF #14873 |
Organisation | Natural Environment Research Council |
Sector | Public |
Country | United Kingdom |
Start | 01/2014 |
End | 12/2014 |
Description | Invited speaker at the INTERNATIONAL SYMPOSIUM ON QUORUM SENSING INHIBITION |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Industry/Business |
Results and Impact | Talk entitled 'AHLs and macrofouling within the marine environment' |
Year(s) Of Engagement Activity | 2015 |