Unfolded (inactive) rhodanese (thiosulfate:cyanide sulfurtransferase, EC 2.8.1.1) can be reactivated in the presence of detergents, e.g. lauryl maltoside (LM). Here, we report the reactivation of urea-unfolded rhodanese in the presence of mixed micelles containing LM and the anionic mitochondrial phospholipid, cardiolipin (CL). Reactivation times increased as the number of CL molecules/micelle ...

The chaperonin GroEL binds to non-native substrate proteins via hydrophobic interactions, preventing their aggregation, which is minimized at low temperatures. In the present study, we investigated the refolding of urea-denatured rhodanese at low temperatures, in the presence of ox-GroEL (oxidized GroEL), which contains increased exposed hydrophobic surfaces and retains its ability to hydrolyse...

Crystalline bovine liver rhodanese, prepared by ammonium sulfate and pH precipitation, has been shown to be comprised of two fully active components present in approximately equal amounts which are separable by polyacrylamide gel electrophoresis and by ion exchange chromatography. The two rhodanese forms, designated A and B on the basis of their order of elution from columns of DEAE-Sephadex, a...

INTRODUCTION The enzyme rhodanese, which catalyzes the for mation of thiocyanate from cyanide and thiosulfate, is of interest to the cancer problem for reasons to be mentioned below. The administration of nitriles causes an increase in the thiocyanate level of the blood and in its urinary excretion. In seeking an explanation for the growth-retarding effect of certain substituted malononitriles ...

1. Rhodanese has been extracted from Thiobacillus denitrificans by ultrasonic disintegration of the cells. 2. Studies with Sephadex columns have shown that the enzyme aggregates, forming a tetramer. 3. The molecular weights of the monomer and of an enzymically active sub-unit one-quarter this size have been determined by gel filtration. 4. Higher-molecular-weight forms of rhodanese are broken d...

Rhodanese (thiosulfate:cyanide sulfurtransferase; EC 2.8.1.1) catalyzes the conversion of thiosulfate and cyanide to thiocyanate and sulfite. Conventional rhodanese assays colorimetrically measure the formation of one or the other of the products. These assays suffer from the fact that there is significant nonbiological formation of these products in addition to the enzymatically catalyzed reac...

The functional adaptive changes in cyanide detoxification in giant panda appear to be response to dietary transition from typical carnivore to herbivorous bear. We tested the absorption of cyanide contained in bamboo/bamboo shoots with a feeding trial in 20 adult giant pandas. We determined total cyanide content in bamboo shoots and giant panda's feces, levels of urinary thiocyanate and tissue ...

Rhodanese is a multifunctional, sulfur transferase that catalyzes the detoxification of cyanide by sulphuration in a double displacement (ping pong) mechanistic reaction. In the present study, small-insert metagenomic library from soil sample collected from Ladakh (3,000-3,600 m.a.s.l) in northwestern Himalayas, India was constructed. Function-driven screening of ~8,500 colonies led to the isol...

Crystalline beef liver rhodanese (thiosulfate : cyanidesulfurtransferase, EC 2.8.1.1) catalyzes sulfur transfer from SSOato CNby a double displacement mechanism (3, 4). The biological role of this reaction is not clear, but its possible involvement in CNdetoxication has been repeatedly stressed. The present study of the specificity of the crystalline beef liver enzyme and of the occurrence of t...

The enzyme rhodanese (thiosulfate sulfurtransferase; EC 2.8.1.1) is inactivated with a half-time of approximately 3 min when incubated with 50 mM NADH. NAD+, however, has virtually no effect on the activity. Inactivation can be prevented by the inclusion of the substrate thiosulfate. The concentration of thiosulfate giving half-protection is 0.038 mM. In addition, NADH, but not NAD+, is a compe...