Non-tuberculous mycobacteria isolated from New Zealand soil environments : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Philosophy in Microbiology at Massey University, Albany, New Zealand

Abstract

There is little information on the diversity of non-tuberculous mycobacteria (NTM) in New Zealand. This project has shown that diverse mycobacteria can be isolated from forest, pastoral and urban environments through the combined use of specialised decontamination techniques and selective media. Mycobacterium avium-intracellulare complex (MAIC) was the most commonly isolated mycobacteria (40%) followed by M. montefiorense/M. triplex (20%). This is the first known isolation ot M. montefiorense/M. triplex from soils in New Zealand. The greatest numbers of mycobacteria were isolated from peat-rich pastoral soils, followed by urban dust/organic matter and native forest soils. The majority of mycobacteria isolated were slow-growing. The greatest numbers of isolates that were unable to be speciated further than Mycobacterium species using 16S rDNA sequencing (i.e. likely to be new species) were isolated from native forest soils.