Bioprospecting : the quest for novel extracellular polymers produced by soil-borne bacteria : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Microbiology at Massey University, Palmerston North, New Zealand

Abstract

Bacteria are ubiquitous in nature, and the surrounding environment. Bacterially produced extracellular polymers, and proteins are of particular value in the fields of medicine, food, science, and industry. Soil is an extremely rich source of bacteria with over 100 million per gram of soil, many of which produce extracellular polymers. Approximately 90% of soil-borne bacteria are yet to be cultured and classified. Here we employed an exploratory approach and culture based method for the isolation of soil-borne bacteria, and assessed their capability for extracellular polymer production. Bacteria that produced mucoid (of a mucous nature) colonies were selected for identification, imaging, and polymer production. Here we characterised three bacterial isolates that produced extracellular polymers, with a focus on one isolate that formed potentially novel proteinaceous cell surface appendages. These appendages have an unknown function, however, I suggest they may be important for bacterial communication, signalling, and nutrient transfer. They may also serve to increase the bacteria’s surface area for nutrient adsorption without compromising structural integrity of the cell. The results from this study contribute to the scientific body of knowledge and provide avenues for further research into bacterial appendage formation.