Rhizobium leguminosarum bv. viciae 3841 (Rlv3841) establishes nitrogen-fixing symbiosis with Viciae legumes such as agriculturally important pea (Pisum sativum). Rlv3841 is able to exist both as a free-living organism and as a nitrogen-fixing symbiont within root nodules. In the progression between these two states it experiences a number of lifestyle changes: growth in the rhizosphere, competing for root proximity, attachment and colonisation, and terminal differentiation into a nitrogen-fixing bacteroid. In my DPhil project I have used a mariner-based transposon vector for high-throughput insertion sequence mutagenesis to characterize the fitness determinants for these different lifestyle changes in Rlv3841 on the whole-genome scale.
(1) Perry, B. J., & Yost, C. K. (2014). Construction of a mariner-based transposon vector for use in insertion sequence mutagenesis in selected members of the Rhizobiaceae. BMC microbiology, 14(1), 1.
(2) Wheatley, R. M., Ramachandran, V. K., Geddes, B. A., Perry, B. J., Yost, C. K., & Poole, P. S. (2017). Role of O2 in the Growth of Rhizobium leguminosarum bv. viciae 3841 on Glucose and Succinate. Journal of Bacteriology, 199(1), e00572-16.
In Oct 2017: DPhil Student, Year 4 of 4 years
This DPhil project is funded by the NERC
Rhizosphere 
Wow! Sounds complicated. Googled you to check I had the right face, and I did. Thanks for your email again Rachel. It really means a lot. Owen Mansfield.