Mycobacterium NBB4 was isolated from freshwater sediment in 2004 as part of a bioprospecting experiment seeking novel soluble di-iron monooxygenases (SDIMOs). This bacterium possesses an unprecedented diversity of MOs, including four distinct SDIMOs and a copper monooxygenase (CuMMO). We have been working to unravel the genetics, biochemistry and physiology of this bacterium, and determine the ecological significance and biotechnology applications of its enzymes. All of the SDIMOs and also the CuMMO of NBB4 are involved in metabolism of gaseous alkanes and alkenes (C2-C4), but the reasons for this apparent functional redundancy are still unknown. Both the wild type organism and recombinants expressing the MO genes are capable of biodegrading priority pollutants (e.g. vinyl chloride and dichloroethane) and can perform interesting biocatalytic reactions (stereospecific oxidation of alkenes to epoxides). I will showcase very recent data that shows how the regulators of hydrocarbon metabolism in NBB4 can be developed into biosensors.