Characterization of arylsulfatase formed by derepressed synthesis in Citrobacter braakii

Arylsulfatase activity was detected in a bacterial strain, Citrobacter braakii 69-b, isolated from soil by enrichment cultivation using porcine gastric mucin. The production of arylsulfatase was derepressed markedly in a synthetic medium by the addition of tyramine. The purified enzyme hydrolyzed 4-nitrophenyl sulfate, 4-nitrocatechol sulfate, and 3-indoxyl sulfate, and was classified as type I arylsulfatase.