All living organisms require phosphorus (P) and nitrogen (N), which exist in many forms, from inorganic phosphate (Pi) or ammonium, to multiple and diverse organic P (Po) and N molecules. As essential elements, bacteria possess multiple mechanisms that allow them to acquire P and N from their surrounding environment. Many environmental niches, including regions of the global ocean and the rhizosphere of crop plants, exhibit N and P limitation, and thus bacteria must possess mechanisms to overcome this nutrient limitation. Over the past seven years, I have contributed to, and led, research uncovering hitherto overlooked mechanisms for N and P acquisition and characterising others. This research has resulted in several published papers, including two first author papers within this field as outputs. In particular, I have contributed to research into the mechanisms displayed by rhizobacteria associated with oilseed rape (Brassica napus), including Pseudomonas and Flavobacteria spp., using analysis of proteomics data. The biological insights provided from this work were used to develop further foci of study, including the activity, functional role and distribution of a newly identified phosphatase, and the extracellular activity of Po-mineralising enzymes and its consequences for Pi availability. I have also led research into the identification, characterisation, and environmental distribution of 2-aminoethylphosphonate (2AEP) transporters, showing a novel 2AEP transporter to be the most transcribed phosphonate transporter in the global ocean. I followed this research with further investigation into the molecular mechanisms underpinning the regulation of 2AEP transport and degradation in Pseudomonas putida BIRD-1. By utilising my developed skill sets in both wet lab and bioinformatics techniques, I also contributed to papers investigating lipid remodelling, a mechanism by which bacteria reduce the quantity of phospholipids in their lipid membranes, in both environmental and pathogenic bacteria. Additionally, I have contributed to, and written, other papers within the field of environmental microbiology, which go beyond the scope of this thesis. As such, the works presented in this thesis represent a coherent body of work demonstrating my contribution to the research field.