EurekaMag.com logo
+ Site Statistics
References:
53,214,146
Abstracts:
29,074,682
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Spectroscopic and catalytic properties of Rhus vernicifera laccase depleted in type 2 copper


Journal of Inorganic Biochemistry 11(2): 115-127
Spectroscopic and catalytic properties of Rhus vernicifera laccase depleted in type 2 copper
1. The type 2 copper in Rhus vernicifera laccase was completely removed without loss of other types of copper. The properties of this protein derivative and the role of type 2 copper in the catalytic action of laccase was investigated. 2. The molar extinction coefficient at 614 nm of the blue chromophore decreases from 5700 to 4700 cm-1 on removal of type 2 copper. There are no apparent absorption changes at other wavelengths in the visible or near ultraviolet region when this copper is taken away. The electron-paramagnetic-resonance (epr) parameter A parallel and the linewidth of type 1 Cu2+ decreases on removal of type 2 copper. 3. The rate of reduction of type 1 Cu2+ is not affected by removal of type 2 copper but the reduction of the two-electron acceptor is greatly impaired. These results strongly support the idea that type 1 Cu2+ is the primary site for electron transfer between substrate and enzyme and that the two-electron acceptor in the native enzyme is reduced by simultaneous electron transfer from reduced types 1 and 2 copper. 4. Reoxidation of types 1 and 3 copper and the formation of the oxygen intermediate are the same processes in native and type-2-depleted enzyme. These observations suggests that type 2 copper is not involved in the formation and rapid decay of the oxygen intermediate and that it is not necessary for the stabilization of this intermediate. 5. Two new epr signals are observed on reoxidation of reduced type-2-depleted laccase. One is temporarily formed on re-reduction of reoxidized enzyme and it is suggested that it might arise from copper, possibly type 3 copper. The other one is stable for hours and it is proposed that it might come from a modified oxygen intermediate.

(PDF same-day service: $19.90)

Accession: 041409544

PMID: 228004

DOI: 10.1016/s0162-0134(00)80177-4



Related references

Low-temperature resonance-Raman spectra of Japanese-lacquer-tree (Rhus vernicifera) laccase, type-2-copper-depleted laccase and H2O2 hydrogen peroxide-treated type-2-copper-depleted laccase. Biochemical journal Molecular aspects including rapid papers 213(2): 503-506, 1983

Low temperature resonance raman spectra of japanese lacquer tree rhus vernicifera laccase type 2 copper depleted laccase and hydrogen per oxide treated type 2 copper depleted laccase. Biochemical Journal 213(2): 503-506, 1983

Reactivity electrochemical and spectroscopic studies of type 2 copper depleted rhus vernicifera laccase. Biochemistry 23(2): 241-247, 1984

Low-temperature resonance-Raman spectra of Japanese-lacquer-tree (Rhus vernicifera) laccase, type-2-copper-depleted laccase and H2O2-treated type-2-copper-depleted laccase. Biochemical Journal 213(2): 503-506, 1983

Optical properties and a new epr signal from type 3 copper in metal depleted rhus vernicifera laccase. Journal of Inorganic Biochemistry 18(2): 113-122, 1983

Optical properties of japanese lacquer tree rhus vernicifera laccase depleted of type 2 copper ii involvement of type 2 copper ii in the 330 nanometer chromophore. Biochemical Journal 187(2): 361-366, 1980

Optical properties of japanese-lacquer-tree (Rhus vernicifera) laccase depleted of type 2 copper(II). Involvement of type-2 copper(II) in the 330nm chromophore. Biochemical Journal 187(2): 361-366, 1980

Electron nuclear double resonance spectra of the type 1 copper centre in Japanese lacquer tree (Rhus vernicifera) laccase, and type 2 copper-depleted laccase. Biochimica et biophysica acta: protein structure and molecular enzymology0, 831(1): 8-12, 1985

Electron nuclear double resonance spectra of the type 1 copper center in japanese lacquer tree rhus vernicifera laccase and type 2 copper depleted laccase. Biochimica et Biophysica Acta 831(1): 8-12, 1985

Effects of laser radiation on rhus vernicifera laccase type 2 copper depleted laccase and stellacyanin. Journal of Inorganic Biochemistry 20(1): 87-92, 1984