Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P04179 (
MnSOD
)
2,777
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Two commonly used assays for superoxide dismutase (SOD) activity have been compared, one using cytochrome c and the other using
XTT
(2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) as the indicating scavenger of superoxide. The use of cyanide to selectively suppress Cu,Zn-SOD and thus to allow assay of both Cu,Zn-SOD and
Mn-SOD
in mixtures of the two was also explored, as was the influence of pH. The
XTT
assay became more sensitive at elevated pH, because the rate of the superoxide/
XTT
reaction declines with increasing pH. This was clearly seen with the Cu,Zn-SOD but barely with
Mn-SOD
because the former retains full activity from pH 5 to 10 while the latter does not. Cyanide reacted with cytochrome c, but not
XTT
, in a concentration- and time-dependent manner and thus diminished its reducibility by superoxide. Cytochromes endogenous to tissue fractions were reduced by the xanthine oxidase reaction and this caused a decrease in absorbance 470 nm which interfered with the
XTT
assay. The alkalinizing effect of cyanide salts and the problems encountered in neutralizing cyanide stock solutions are discussed.
...
PMID:Assay of superoxide dismutase: cautions relevant to the use of cytochrome c, a sulfonated tetrazolium, and cyanide. 1170 Sep 91
