Properties of rabbit liver glutathione reductase reconstituted with FAD analogs

Zanetti, G. ; Beretta, C. ; Malandra, D.

Amsterdam : Elsevier
ISSN:
0003-9861
Source:
Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
Topics:
Biology
Chemistry and Pharmacology
Physics
Type of Medium:
Electronic Resource
URL:
_version_ 1798292194133540864
autor Zanetti, G.
Beretta, C.
Malandra, D.
autorsonst Zanetti, G.
Beretta, C.
Malandra, D.
book_url http://dx.doi.org/10.1016/0003-9861(86)90652-1
datenlieferant nat_lic_papers
fussnote The FAD binding site of rabbit liver glutathione reductase has been explored by reconstitution of the apoprotein with several FAD analogs modified in the isoalloxazine ring. The apoglutathione reductase binds the p-quinoid form of 8-mercapto-FAD, suggesting that the protein stabilizes a negative charge in the N"1C"2O position of the pyrimidine subnucleus. The main absorption peak in the visible spectrum of the 8-mercapto-FAD-enzyme is at 585 nm; treatment of the reconstituted protein with reducing agents of disulfide groups induces a reversible hypochromic shift of 20 nm of the peak. Thus, in 8-mercapto-FAD-glutathione reductase, the oxidation-reduction state of the active center disulfide can be monitored. The chemical reactivity toward methylmethanethiosulfonate and iodoacetamide of the 8-mercapto-FAD-enzyme shows that the flavin position 8 is freely accessible to solvent. However, position 2 is buried within the protein molecule as judged from the lack of reactivity of the 2-thio-FAD-enzyme with methylmethanethiosulfonate. Hydrogen peroxide reacts slowly with both 2-thio-FAD-enzyme and native glutathione reductase, yielding inactive enzyme with a modified spectrum; the prosthetic group is still protein bound. Differences in the active site of the rabbit liver enzyme compared to the human erythrocyte glutathione reductase are evidenced by use of FAD analogs: the peaks of reconstituted liver enzymes are shifted about 10 nm toward longer wavelengths.
hauptsatz hsatz_simple
identnr NLZ183421167
issn 0003-9861
journal_name Archives of Biochemistry and Biophysics
materialart 1
package_name Elsevier
publikationsort Amsterdam
publisher Elsevier
reference 244 (1986), S. 831-837
search_space articles
shingle_author_1 Zanetti, G.
Beretta, C.
Malandra, D.
shingle_author_2 Zanetti, G.
Beretta, C.
Malandra, D.
shingle_author_3 Zanetti, G.
Beretta, C.
Malandra, D.
shingle_author_4 Zanetti, G.
Beretta, C.
Malandra, D.
shingle_catch_all_1 Zanetti, G.
Beretta, C.
Malandra, D.
Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
0003-9861
00039861
Elsevier
shingle_catch_all_2 Zanetti, G.
Beretta, C.
Malandra, D.
Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
0003-9861
00039861
Elsevier
shingle_catch_all_3 Zanetti, G.
Beretta, C.
Malandra, D.
Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
0003-9861
00039861
Elsevier
shingle_catch_all_4 Zanetti, G.
Beretta, C.
Malandra, D.
Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
0003-9861
00039861
Elsevier
shingle_title_1 Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
shingle_title_2 Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
shingle_title_3 Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
shingle_title_4 Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
sigel_instance_filter dkfz
geomar
wilbert
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albert
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source_archive Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
timestamp 2024-05-06T08:44:38.830Z
titel Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
titel_suche Properties of rabbit liver glutathione reductase reconstituted with FAD analogs
The FAD binding site of rabbit liver glutathione reductase has been explored by reconstitution of the apoprotein with several FAD analogs modified in the isoalloxazine ring. The apoglutathione reductase binds the p-quinoid form of 8-mercapto-FAD, suggesting that the protein stabilizes a negative charge in the N"1C"2O position of the pyrimidine subnucleus. The main absorption peak in the visible spectrum of the 8-mercapto-FAD-enzyme is at 585 nm; treatment of the reconstituted protein with reducing agents of disulfide groups induces a reversible hypochromic shift of 20 nm of the peak. Thus, in 8-mercapto-FAD-glutathione reductase, the oxidation-reduction state of the active center disulfide can be monitored. The chemical reactivity toward methylmethanethiosulfonate and iodoacetamide of the 8-mercapto-FAD-enzyme shows that the flavin position 8 is freely accessible to solvent. However, position 2 is buried within the protein molecule as judged from the lack of reactivity of the 2-thio-FAD-enzyme with methylmethanethiosulfonate. Hydrogen peroxide reacts slowly with both 2-thio-FAD-enzyme and native glutathione reductase, yielding inactive enzyme with a modified spectrum; the prosthetic group is still protein bound. Differences in the active site of the rabbit liver enzyme compared to the human erythrocyte glutathione reductase are evidenced by use of FAD analogs: the peaks of reconstituted liver enzymes are shifted about 10 nm toward longer wavelengths.
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