THE ROLE OF SULFOACETALDEHYDE SULFO-LYASE IN THE MINERALIZATION OF ISETHIONATE BY AN ENVIRONMENTAL ACINETOBACTER ISOLATE

An environmental Acinetobacter isolate, strain ICD. utilized isethiona te at concentrations up to at least 20 mM as carbon and energy source, with essentially quantitative sulfate accumulation. The initial step in isethionate metabolism is likely to be its oxidation to sulfoacetal dehyde since inducible sulfoacetaldehyde sulfo-lyase activity was demo nstrated in isethionate-grown cells by in vitro assay and gel zymograp hy; sulfoacetaldehyde itself did not induce the enzyme. Isethionate-gr own cells of Acinetobacter sp. ICD, unlike those of most other C-S bon d-cleaving strains described, also contained an inducible sulfite-oxid izing activity. The results provide further evidence that sulfoacetald ehyde sulfo-lyase plays a central role in the mineralization of biogen ic sulfonates.