TY - JOUR
T1 - Bromoperoxidase activity of vanadate-substituted acid phosphatases from Shigella flexneri and Salmonella enterica ser. typhimurium
AU - Tanaka, Naoko
AU - Dumay, Valérie
AU - Liao, Qianning
AU - Lange, Alex J
AU - Wever, Ron
PY - 2002
Y1 - 2002
N2 - Vanadium haloperoxidases and the bacterial class A non-specific acid phosphatases have a conserved active site. It is shown that vanadate-substituted recombinant acid phosphatase from Shigella flexneri (PhoN-Sf) and Salmonella enterica ser. typhimurium (PhoN-Se) in the presence of H2O2 are able to oxidize bromide to hypobromous acid. Vanadate is essential for this activity. The kinetic parameters for the artificial bromoperoxidases have been determined. The Km value for H2O2 is about the same as that for the vanadium bromoperoxidases from the seaweed Ascophyllum nodosum. However, the Km value for Br- is about 10-20 times higher, and the turnover values of about 3.4 min-1 and 33 min-1 for PhoN-Sf and PhoN-Se, respectively, are much slower, than those of the native bromoperoxidase. Thus, despite the striking similarity in the active-site structures of the vanadium haloperoxidases and the acid phophatase, the turnover frequency is low, and clearly the active site of acid phosphatases is not optimized for haloperoxidase activity. Like the native vanadium bromoperoxidase, the vanadate-substituted PhoN-Sf and PhoN-Se catalyse the enantioselective sulfoxidation of thioanisole.
AB - Vanadium haloperoxidases and the bacterial class A non-specific acid phosphatases have a conserved active site. It is shown that vanadate-substituted recombinant acid phosphatase from Shigella flexneri (PhoN-Sf) and Salmonella enterica ser. typhimurium (PhoN-Se) in the presence of H2O2 are able to oxidize bromide to hypobromous acid. Vanadate is essential for this activity. The kinetic parameters for the artificial bromoperoxidases have been determined. The Km value for H2O2 is about the same as that for the vanadium bromoperoxidases from the seaweed Ascophyllum nodosum. However, the Km value for Br- is about 10-20 times higher, and the turnover values of about 3.4 min-1 and 33 min-1 for PhoN-Sf and PhoN-Se, respectively, are much slower, than those of the native bromoperoxidase. Thus, despite the striking similarity in the active-site structures of the vanadium haloperoxidases and the acid phophatase, the turnover frequency is low, and clearly the active site of acid phosphatases is not optimized for haloperoxidase activity. Like the native vanadium bromoperoxidase, the vanadate-substituted PhoN-Sf and PhoN-Se catalyse the enantioselective sulfoxidation of thioanisole.
KW - Acid phosphatase
KW - Brominating activity
KW - Enantioselective sulfoxidation
KW - Vanadium bromoperoxidase
KW - Vanadium chloroperoxidase
UR - http://www.scopus.com/inward/record.url?scp=0036239797&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036239797&partnerID=8YFLogxK
U2 - 10.1046/j.1432-1033.2002.02871.x
DO - 10.1046/j.1432-1033.2002.02871.x
M3 - Article
C2 - 11985594
AN - SCOPUS:0036239797
SN - 0014-2956
VL - 269
SP - 2162
EP - 2167
JO - European Journal of Biochemistry
JF - European Journal of Biochemistry
IS - 8
ER -