A STUDY OF ARYLSULFATASE ACTIVITY IN PROTEUS RETTGERI

Abstract

Arylsulfatase was detected in a strain of Froteus rettgeri using two substrates, nitrocatechol sulfate (NCS) and nitrophenyl sulfate (NTS). Activity was found when the organism was grown in a chemically defined medium with methionine as the only added source of sulfur. No activity was demonstrated when sulfate was substituted for methionine in the growth medium.Maximum hydrolysis of NCS occurred at pH 6.7 in 0.15 M phosphate buffer at 37 °C and maximum hydrolysis of NPS at pH 8.3 in 0.75 M Tris–acetate buffer at 34.5 °C.Sodium cyanide (10−2 M) inhibited hydrolysis of both substrates and sodium sulfate (10−2 M) inhibited hydrolysis of NCS but not NPS. With sodium dihydrogen phosphate (10−2 M) there was increased hydrolysis of NCS and inhibition of NPS hydrolysis.The sulfatase activity in P. rettgeri is compared with that reported in other bacterial systems.