....................................................................................................................................... 1 ACKNOWLEDGMENTS .................................................................................................................... 2 LIST OF FIGURES ............................................................................................................................ 8 LIST OF TABLES AND EQUATIONS.............................................................................................. 11 LIST OF ABRIEVIATAIONS ............................................................................................................ 12 CHAPTER 1 – INTRODUCTION ..................................................................................................... 14 1.1 Secretion systems...................................................................................................................... 14 1.1.1. Bacteria: adaptation and survival.................................................................................... 14 1.1.2. Secretion pathways in bacteria ....................................................................................... 14 1.1.3. Type I multidrug resistance (MDR) efflux systems ......................................................... 15 1.1.4. Antibiotic resistance and the resistance nodulation division (RND) family ..................... 17 1.1.5. The role of RND efflux systems in bacterial pathogenicity ............................................. 18 1.2. The AcrAB-TolC efflux system.................................................................................................. 18 1.2.1. The outer membrane protein TolC.................................................................................. 18 1.2.2. AcrAB-TolC RND efflux system ...................................................................................... 20 1.2.3. AcrAB-TolC assembly..................................................................................................... 20 1.2.4 The membrane fusion protein AcrA ................................................................................. 20 1.2.5. Substrate binding for export via TolC ............................................................................. 21 1.2.6. Substrates of the resistance nodulation division efflux system....................................... 23 1.3. Bacterial fatty acid and hydrocarbon production ....................................................................... 23 1.3.1. Microbial bio-fuels. .......................................................................................................... 23 1.3.2. Bacterial fatty acids......................................................................................................... 24 1.3.3 Fatty acid synthesis in bacteria........................................................................................ 25 1.3.4. Hydrocarbon biosynthesis .............................................................................................. 25 1.3.5. Advantages of utilising bacteria in bio-fuel production.................................................... 25 1.3.6. Hydrocarbon producing bacteria..................................................................................... 28 1.3.7. Vibrio furnissii ................................................................................................................. 29 1.4. The secretion of compounds for cell-cell signalling .................................................................. 30 1.4.1. Quorum derived signalling .............................................................................................. 30 1.4.2. The quorum regulatory Lux pathway in V. fischeri, V. harveyi and V. cholerae ............. 31 1.4.3. Bacterial signalling molecules: Homoserine lactones and autoinducers ........................ 34