TY - JOUR
T1 - Nitric Oxide Reductase Activity in Heme-Nonheme Binuclear Engineered Myoglobins through a One-Electron Reduction Cycle
AU - Sabuncu, Sinan
AU - Reed, Julian H.
AU - Lu, Yi
AU - Moënne-Loccoz, Pierre
N1 - Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/12/19
Y1 - 2018/12/19
N2 - Fe B Mbs are structural and functional models of native bacterial nitric oxide reductases (NORs) generated through engineering of myoglobin. These biosynthetic models replicate the heme-nonheme diiron site of NORs and allow substitutions of metal centers and heme cofactors. Here, we provide evidence for multiple NOR turnover in monoformyl-heme-containing Fe B Mb1 proteins loaded with Fe II , Co II , or Zn II metal ions at the Fe B site (Fe II /Co II /Zn II -Fe B Mb1(MF-heme)). FTIR detection of the (NNO) band of N 2 O at 2231 cm -1 provides a direct quantitative measurement of the product in solution. A maximum number of turnover is observed with Fe II -Fe B Mb1(MF-heme), but the NOR activity is retained when the Fe B site is loaded with Zn II . These data support the viability of a one-electron semireduced pathway for the reduction of NO at binuclear centers in reducing conditions.
AB - Fe B Mbs are structural and functional models of native bacterial nitric oxide reductases (NORs) generated through engineering of myoglobin. These biosynthetic models replicate the heme-nonheme diiron site of NORs and allow substitutions of metal centers and heme cofactors. Here, we provide evidence for multiple NOR turnover in monoformyl-heme-containing Fe B Mb1 proteins loaded with Fe II , Co II , or Zn II metal ions at the Fe B site (Fe II /Co II /Zn II -Fe B Mb1(MF-heme)). FTIR detection of the (NNO) band of N 2 O at 2231 cm -1 provides a direct quantitative measurement of the product in solution. A maximum number of turnover is observed with Fe II -Fe B Mb1(MF-heme), but the NOR activity is retained when the Fe B site is loaded with Zn II . These data support the viability of a one-electron semireduced pathway for the reduction of NO at binuclear centers in reducing conditions.
UR - http://www.scopus.com/inward/record.url?scp=85058541720&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85058541720&partnerID=8YFLogxK
U2 - 10.1021/jacs.8b11037
DO - 10.1021/jacs.8b11037
M3 - Article
C2 - 30512937
AN - SCOPUS:85058541720
SN - 0002-7863
VL - 140
SP - 17389
EP - 17393
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 50
ER -