Open AccessNitrilase of Rhodococcus rhodochrous J1
Author(s) -
Nagasawa Toru,
Wieser Marco,
Nakamura Tetsuji,
Iwahara Hitomi,
Yoshida Toyokazu,
Gekko Kunihiko
Publication year - 2000
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1327.2000.00983.x
Subject(s) - benzonitrile , acrylonitrile , nitrilase , rhodococcus rhodochrous , chemistry , enzyme , rhodococcus , ammonium sulfate , ammonium , hydrolysis , organic chemistry , medicinal chemistry , nuclear chemistry , copolymer , polymer
Nitrilase‐containing resting cells of Rhodococcus rhodochrous J1 converted acrylonitrile and benzonitrile to the corresponding acids, but the purified nitrilase hydrolyzed only benzonitrile, and not acrylonitrile. The activity of the purified enzyme towards acrylonitrile was recovered by preincubation with 10 m m benzonitrile, but not by preincubation with aliphatic nitriles such as acrylonitrile. It was shown by light‐scattering experiments, that preincubation with benzonitrile led to the assembly of the inactive, purified and homodimeric 80‐kDa enzyme to its active 410‐kDa aggregate, which was proposed to be a decamer. Furthermore, the association concomitant with the activation was reached after dialysis of the enzyme against various salts and organic solvents, with the highest recovery reached at 10% saturated ammonium sulfate and 50% (v/v) glycerol, and by preincubation at increased temperatures or enzyme concentrations.