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: EC:1.3.5.1 (
succinate dehydrogenase
)
8,177
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The interaction of the sulfurtransferase rhodanese (EC 2.8.1.1) with
succinate dehydrogenase
(EC 1.3.99.1), yeast alcohol dehydrogenase (EC 1.1.1.1) and bovine serum albumin was studied. Succinate dehydrogenase incorporates the sulfane sulfur of [35S]rhodanese and, in the presence of unlabelled rhodanese, also incorporates that of [35S]thiosulfate. Rhodanese releases most of its transferable sulfur and is re-loaded in the presence of thiosulfate. Rhodanese undergoes similar modifications with yeast alcohol dehydrogenase but this latter does not bind 35S in amounts comparable to those incorporated in
succinate dehydrogenase
: nearly all the 35S released by [35S]rhodanese is with low-molecular-weight compounds. Bovine serum albumin also binds very little sulfur and [35S]rhodanese present in the reaction mixture does not discharge its radioactive sulfur nor does it take up sulfur from thiosulfate. Sulfur release from rhodanese appears to depend on the presence of - SH groups in the acceptor protein. Sulfur incorporated into
succinate dehydrogenase
was analytically determined as sulfide. A comparison of the optical spectra of
succinate dehydrogenase
preparations incubated with or without rhodanese indicates that there is an effect of the sulfurtransferase on the iron-sulfur absorption of the flavorprotein. The interaction of rhodanese with
succinate dehydrogenase
greatly decreases the catalytic activity of rhodanese with respect to thiocyanate formation. This is attributed to modifications in rhodanese associated with the reduction of sulfane sulfur to sulfide.
Thiosulfate
in part protects from this deactivation. The reconstitutive capacity of
succinate dehydrogenase
increased in parallel with sulfur incorporated in that enzyme following its interaction with rhodanese.
...
PMID:Rhodanese-Mediated sulfur transfer to succinate dehydrogenase. 31 99
Hypo
- and hyperthyroidism have been associated with changes in the activities of mitochondrial enzymes in homogenates of skeletal muscles, but it is unclear whether such changes were due to changes in single fibre enzyme activities or to previously documented changes in relative numbers of fibres. In this study the activities of the mitochondrial enzymes alpha-glycerol phosphate dehydrogenase (m-alpha GPDH) and
succinate dehydrogenase
(
SDH
) were measured in single fibres of the soleus and gastrocnemius muscles of the rat by cytochemical assays. In the soleus muscles of hypothyroid animals there was a decrease in the mean percentage (+/- S.D.) of type II fibres from 8.0 +/- 6.0 to 0.8 +/- 1.9% (P less than 0.05) and decreases in
SDH
activities in all fibre types (P less than 0.005). In the gastrocnemius muscles of these animals there were no changes in fibre composition but type IIB fibres had reduced (P less than 0.05) m-alpha GPDH activities. In the hyperthyroid animals, in which body weight had increased relative to the euthyroid animals, there were increases in the percentages of type IC and type II fibres in the soleus from 4.3 +/- 1.7 to 13.1 +/- 9.0% (P less than 0.05) and from 9.6 +/- 7.2 to 33.4 +/- 9.6% (P less than 0.005) respectively and an increase in the percentage of type IIA fibres in the gastrocnemius from 92.9 +/- 2.3 to 97.0 +/- 2.9% (P less than 0.05). However, there were no increases in single fibre mitochondrial enzyme activities.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:The effects of hypo- and hyperthyroidism on fibre composition and mitochondrial enzyme activities in rat skeletal muscle. 161 38
