Solubilization, purification, and properties of membrane-bound D-glucono-delta-lactone hydrolase from Gluconobacter oxydans.
Membrane-bound glucono-delta-lactonase (MGL) was purified to homogeneity from the membrane fraction of Gluconobacter oxydans IFO 3244. After solubilization with 1 M CaCl2, MGL was purified in the presence of Ca2+ and detergent. A single band corresponding to 60 kDa appeared in SDS-PAGE. The molecular weight of MGL was judged to be 120 k. Differently from cytoplasmic lactonases, MGL showed optimum pH in an acidic range of 5-5.5. It was highly sensitive to metal-chelating agents such as EDTA, and the lost MGL activity was restored to the original level by the addition of divalent cations such as Ca2+ or Mg2+. The purified MGL was strictly dependent on Ca2+ and underwent rapid denaturing precipitation on Ca2+ depletion even in the presence of detergent. This communication can be the first one dealing with the solubilization, purification and properties of MGL.
Shinagawa
Emiko
E
Department of Chemical and Biological Engineering, Ube National College of Technology. emiko@ube-k.ac.jp
Ano
Yoshitaka
Y
Yakushi
Toshiharu
T
Adachi
Osao
O
Matsushita
Kazunobu
K
D001426:Bacterial Proteins; D002118:Calcium; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000302:isolation & purification*; D002413:Cations, Divalent; D005942:Gluconates; D020600:Gluconobacter oxydans / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007783:Lactones; D008565:Membrane Proteins; D008970:Molecular Weight; D012995:Solubility
D001426:Bacterial Proteins; D002413:Cations, Divalent; D005942:Gluconates; D007783:Lactones; D008565:Membrane Proteins; D002265:Carboxylic Ester Hydrolases; C019103:delta-lactonase; D002118:Calcium; C010730:beta-glucono-1,5-lactone