Objective In the last three years one of the most fundamental changes in our perception of microbial ecosystems, is the recognition that most bacteria have specialised cell to cell diffusible signalling systems (quorum) sensors) that allow them to constantly monitor their cell density. This is achieved by secretion of N-acyl homoserine lactones (AHLs); as these compounds accumulate they are recognized by regulatory proteins that induce (and possibly repress) expression of genes in a cell-density dependent manner. It is now apparent that "cross talk" can occur by bacteria from one genus reacting to AHLs made by bacteria from another genus. These signalling systems appear to be particularly important in soil bacteria, resulting in the induction of genes that influence a range of physiologically diverse processes that are important for pathogenesis, symbiosis, plasmid transfer, enzyme secretion and production of small metabolites (antibiotics etc) important for survival in soils and in the rhizosphere. These processes are all likely to be important with respect to the efficacy of inoculant strains. Undoubtedly, most (if not all) commercial bacterial inoculants that are currently used (or are being developed) as biofertiliser, biocontrol or bio- remediation agents, utilise AHL based communication systems. However, although those physiological traits crucial for inoculant efficacy are probably controlled by AHL-based signalling, we currently know very little about the role of quorum sensing systems with regard to plant microbe interactions or on the effects on the indigenous micro-flora. The design of inoculant strains must now take cognisance of quorum sensing and there is a need to evaluate this type of communication with regard to inoculant development and environmental impact. The objectives of this proposal are: (a) Characterise the quorum sensing systems used by Pseudomonas and Rhizobium inoculant strains. (b) Identify the genes involved in quorum sensing in these inoculant strains . (c) Synthesise novel quorum sensing molecules to test their role in plant microbe interactions. (d) Initiate an Analysis of the role of quorum sensing systems in general performance in-vitro and in efficacy of biofertilisers and biocontrol bacteria using mutants defective in production and/or perception. (e) Assess the potential for: inoculant improvement; alterations in viability (both in shelf life and soil survival) and effects of inoculants on plasmid transfer in soil and on pathogenicity of specific indigenous soil plant pathogens. Fields of science natural sciencesbiological sciencesmicrobiologybacteriologymedical and health sciencesbasic medicinepharmacology and pharmacypharmaceutical drugsantibioticsnatural sciencesbiological sciencesecologyecosystemsnatural sciencesbiological sciencesbiological behavioural sciencesethologybiological interactionsnatural sciencesbiological sciencesbiochemistrybiomoleculesproteinsenzymes Programme(s) FP4-BIOTECH 2 - Specific research, technological development and demonstration programme in the field of biotechnology, 1994-1998 Topic(s) 070202 - Biofertilizers Call for proposal Data not available Funding Scheme CSC - Cost-sharing contracts Coordinator John Innes Centre EU contribution No data Address Sainsbury Laboratory Colney Lane NR4 7UH Norwich United Kingdom See on map Total cost No data Participants (8) Sort alphabetically Sort by EU Contribution Expand all Collapse all CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE France EU contribution No data Address Avenue de la Terrasse 1Bètiment 23 91190 GIF SUR YVETTE See on map Total cost No data Danmarks Tekniske Universitet Denmark EU contribution No data Address 2800 Lyngby See on map Total cost No data Irish Sugar Company Plc Ireland EU contribution No data Address Athy Road 2 Carlow See on map Total cost No data LEIDEN UNIVERSITY Netherlands EU contribution No data Address 64,Wassenaarseweg 64 Clusius Laboratorium 2333 AL LEIDEN See on map Total cost No data MicroBio Ltd United Kingdom EU contribution No data Address Maxted Road Boundary Way HP2 7SU Hemel Hempstead See on map Total cost No data UNIVERSITA DEGLI STUDI DI PADOVA Italy EU contribution No data Address Strada Romea 16 35020 ALBIGNASEGO See on map Total cost No data UNIVERSITY COLLEGE CORK, NATIONAL UNIVERSITY OF IRELAND, CORK Ireland EU contribution No data Address Western Road Biomerit 30 Cork See on map Total cost No data University of Nottingham United Kingdom EU contribution No data Address University Park NG7 2RD Nottingham See on map Links Website Opens in new window Total cost No data