The C2-sulfonates isethionate (2-hydroxyethanesulfonate) and sulfoacetate are widespread natural products; they are also produced industrially for use in skin-care products and the formulation of pharmaceuticals. Despite their significant abundance, neither the degradation nur the formatio of these compounds by bacteria has been elucidated in details. Initial studies related to work on the degradative pathway for taurine (2-aminoethanesulfonate) show that all pathways share a key intermediate, sulfoacetaldehyde. The initial enzymes leading from isethionate and sulfoacetate to this intermediate are unknown. Further work with taurine, as a nitrogen source, showed the generation and excretion of isethionate or sulfoacetate. This project will elucidate the microbial biochemistry of the degradation of isethionate and sulfoacetate, on the one hand, and of the production of these compounds on the other. Reverse genetics will allow the corresponding genes and flanking regions to be identified and sequenced, though some surroundings should be available form genome sequencing projects. Given clusters of genes in taurine degradation, we anticipate clusters in the pathways under study. The clusters should allow candidates for transport systems, regulators and exporters of sulfo-oxyanions to be identified and characterized.