Enzymes
UniProtKB help_outline | 14,366 proteins |
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Namehelp_outline
[sulfur-carrier protein ThiS]-C-terminal Gly-Gly-AMP
Identifier
RHEA-COMP:12910
Reactive part
help_outline
- Name help_outline C-terminal Gly-Gly-AMP Identifier CHEBI:90618 Charge -1 Formula C14H18N7O9P SMILEShelp_outline N1(C2=C(C(=NC=N2)N)N=C1)[C@@H]3O[C@H](COP([O-])(OC(CNC(CN*)=O)=O)=O)[C@H]([C@H]3O)O 2D coordinates Mol file for the small molecule Search links Involved in 7 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline AH2 Identifier CHEBI:17499 Charge 0 Formula RH2 SMILEShelp_outline *([H])[H] 2D coordinates Mol file for the small molecule Search links Involved in 2,713 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
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Namehelp_outline
S-sulfanyl-L-cysteinyl-[cysteine desulfurase]
Identifier
RHEA-COMP:12157
Reactive part
help_outline
- Name help_outline S-sulfanyl-L-cysteine residue Identifier CHEBI:61963 Charge 0 Formula C3H5NOS2 SMILEShelp_outline C([C@H](CSS)N*)(=O)* 2D coordinates Mol file for the small molecule Search links Involved in 16 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
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Namehelp_outline
[sulfur-carrier protein ThiS]-C-terminal Gly-NH-CH2-C(O)SH
Identifier
RHEA-COMP:12908
Reactive part
help_outline
- Name help_outline C-terminal Gly-NH-CH(2)-C(O)SH residue Identifier CHEBI:90619 Charge 0 Formula C4H7N2O2S SMILEShelp_outline SC(CNC(CN*)=O)=O 2D coordinates Mol file for the small molecule Search links Involved in 6 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline A Identifier CHEBI:13193 Charge Formula R SMILEShelp_outline * 2D coordinates Mol file for the small molecule Search links Involved in 2,783 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline AMP Identifier CHEBI:456215 Charge -2 Formula C10H12N5O7P InChIKeyhelp_outline UDMBCSSLTHHNCD-KQYNXXCUSA-L SMILEShelp_outline Nc1ncnc2n(cnc12)[C@@H]1O[C@H](COP([O-])([O-])=O)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 487 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H+ Identifier CHEBI:15378 Charge 1 Formula H InChIKeyhelp_outline GPRLSGONYQIRFK-UHFFFAOYSA-N SMILEShelp_outline [H+] 2D coordinates Mol file for the small molecule Search links Involved in 9,176 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
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Namehelp_outline
L-cysteinyl-[cysteine desulfurase]
Identifier
RHEA-COMP:12158
Reactive part
help_outline
- Name help_outline L-cysteine residue Identifier CHEBI:29950 Charge 0 Formula C3H5NOS SMILEShelp_outline C(=O)(*)[C@@H](N*)CS 2D coordinates Mol file for the small molecule Search links Involved in 123 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
RHEA:43340 | RHEA:43341 | RHEA:43342 | RHEA:43343 | |
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Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
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Publications
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The role of the cysteine residues of ThiI in the generation of 4-thiouridine in tRNA.
Mueller E.G., Palenchar P.M., Buck C.J.
The enzyme ThiI is common to the biosynthetic pathways leading to both thiamin and 4-thiouridine in tRNA. We earlier noted the presence of a motif shared with sulfurtransferases, and we reported that the cysteine residue (Cys-456 of Escherichia coli ThiI) found in this motif is essential for activ ... >> More
The enzyme ThiI is common to the biosynthetic pathways leading to both thiamin and 4-thiouridine in tRNA. We earlier noted the presence of a motif shared with sulfurtransferases, and we reported that the cysteine residue (Cys-456 of Escherichia coli ThiI) found in this motif is essential for activity (Palenchar, P. M., Buck, C. J., Cheng, H., Larson, T. J., and Mueller, E. G. (2000) J. Biol. Chem. 275, 8283-8286). In light of that finding and the report of the involvement of the protein IscS in the reaction (Kambampati, R., and Lauhon, C. T. (1999) Biochemistry 38, 16561-16568), we proposed two mechanisms for the sulfur transfer mediated by ThiI, and both suggested possible involvement of the thiol group of another cysteine residue in ThiI. We have now substituted each of the cysteine residues with alanine and characterized the effect on activity in vivo and in vitro. Cys-108 and Cys-202 were converted to alanine with no significant effect on ThiI activity, and C207A ThiI was only mildly impaired. Substitution of Cys-344, the only cysteine residue conserved among all sequenced ThiI, resulted in the loss of function in vivo and a 2700-fold reduction in activity measured in vitro. We also examined the possibility that ThiI contains an iron-sulfur cluster or disulfide bonds in the resting state, and we found no evidence to support the presence of either species. We propose that Cys-344 forms a disulfide bond with Cys-456 during turnover, and we present evidence that a disulfide bond can form between these two residues in native ThiI and that disulfide bonds do form in ThiI during turnover. We also discuss the relevance of these findings to the biosynthesis of thiamin and iron-sulfur clusters. << Less
J. Biol. Chem. 276:33588-33595(2001) [PubMed] [EuropePMC]
This publication is cited by 1 other entry.
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Evidence for the transfer of sulfane sulfur from IscS to ThiI during the in vitro biosynthesis of 4-thiouridine in Escherichia coli tRNA.
Kambampati R., Lauhon C.T.
IscS from Escherichia coli is a cysteine desulfurase that has been shown to be involved in Fe-S cluster formation. The enzyme converts L-cysteine to L-alanine and sulfane sulfur (S(0)) in the form of a cysteine persulfide in its active site. Recently, we reported that IscS can donate sulfur for th ... >> More
IscS from Escherichia coli is a cysteine desulfurase that has been shown to be involved in Fe-S cluster formation. The enzyme converts L-cysteine to L-alanine and sulfane sulfur (S(0)) in the form of a cysteine persulfide in its active site. Recently, we reported that IscS can donate sulfur for the in vitro biosynthesis of 4-thiouridine (s(4)U), a modified nucleotide in tRNA. In addition to IscS, s(4)U synthesis in E. coli also requires the thiamin biosynthetic enzyme ThiI, Mg-ATP, and L-cysteine as the sulfur donor. We now report evidence that the sulfane sulfur generated by IscS is transferred sequentially to ThiI and then to tRNA during the in vitro synthesis of s(4)U. Treatment of ThiI with 5-((2-iodoacetamido)ethyl)-1-aminonapthalene sulfonic acid (I-AEDANS) results in irreversible inhibition, suggesting the presence of a reactive cysteine that is required for binding and/or catalysis. Both ATP and tRNA can protect ThiI from I-AEDANS inhibition. Finally, using gel shift and protease protection assays, we show that ThiI binds to unmodified E. coli tRNA(Phe). Together, these results suggest that ThiI is a recipient of S(0) from IscS and catalyzes the ultimate sulfur transfer step in the biosynthesis of s(4)U. << Less
J. Biol. Chem. 275:10727-10730(2000) [PubMed] [EuropePMC]
This publication is cited by 1 other entry.