Biotin sulfoxide reductase; This enzyme may serve as a scavenger, allowing the cell to utilize biotin sulfoxide as a biotin source. It reduces a spontaneous oxidation product of biotin, D-biotin D-sulfoxide (BSO or BDS), back to biotin. Also exhibits methionine-(S)-sulfoxide (Met-S-SO) reductase activity, acting specifically on the (S) enantiomer in the free, but not the protein-bound form. It thus plays a role in assimilation of oxidized methionines.

Molybdopterin biosynthesis protein A; Catalyzes, together with MoaC, the conversion of 5'-GTP to cyclic pyranopterin monophosphate (cPMP or molybdopterin precursor Z).

Biotin sulfoxide reductase; This enzyme may serve as a scavenger, allowing the cell to utilize biotin sulfoxide as a biotin source. It reduces a spontaneous oxidation product of biotin, D-biotin D-sulfoxide (BSO or BDS), back to biotin. Also exhibits methionine-(S)-sulfoxide (Met-S-SO) reductase activity, acting specifically on the (S) enantiomer in the free, but not the protein-bound form. It thus plays a role in assimilation of oxidized methionines.

Molybdopterin synthase, small subunit; Involved in sulfur transfer in the conversion of molybdopterin precursor Z to molybdopterin. Belongs to the MoaD family.

Biotin sulfoxide reductase; This enzyme may serve as a scavenger, allowing the cell to utilize biotin sulfoxide as a biotin source. It reduces a spontaneous oxidation product of biotin, D-biotin D-sulfoxide (BSO or BDS), back to biotin. Also exhibits methionine-(S)-sulfoxide (Met-S-SO) reductase activity, acting specifically on the (S) enantiomer in the free, but not the protein-bound form. It thus plays a role in assimilation of oxidized methionines.

Molybdopterin synthase, large subunit; Converts molybdopterin precursor Z to molybdopterin. This requires the incorporation of two sulfur atoms into precursor Z to generate a dithiolene group. The sulfur is provided by MoaD.

Biotin sulfoxide reductase; This enzyme may serve as a scavenger, allowing the cell to utilize biotin sulfoxide as a biotin source. It reduces a spontaneous oxidation product of biotin, D-biotin D-sulfoxide (BSO or BDS), back to biotin. Also exhibits methionine-(S)-sulfoxide (Met-S-SO) reductase activity, acting specifically on the (S) enantiomer in the free, but not the protein-bound form. It thus plays a role in assimilation of oxidized methionines.

6-N-hydroxylaminopurine detoxification oxidoreductase; Protein involved in electron carrier activity.

Biotin sulfoxide reductase; This enzyme may serve as a scavenger, allowing the cell to utilize biotin sulfoxide as a biotin source. It reduces a spontaneous oxidation product of biotin, D-biotin D-sulfoxide (BSO or BDS), back to biotin. Also exhibits methionine-(S)-sulfoxide (Met-S-SO) reductase activity, acting specifically on the (S) enantiomer in the free, but not the protein-bound form. It thus plays a role in assimilation of oxidized methionines.

6-N-hydroxylaminopurine resistance protein.

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

Cysteine desulfurase (tRNA sulfurtransferase), PLP-dependent; Master enzyme that delivers sulfur to a number of partners involved in Fe-S cluster assembly, tRNA modification or cofactor biosynthesis. Catalyzes the removal of elemental sulfur from cysteine to produce alanine. Functions as a sulfur delivery protein for Fe-S cluster synthesis onto IscU, an Fe-S scaffold assembly protein, as well as other S acceptor proteins. Preferentially binds to disordered IscU on which the Fe-S is assembled, IscU converts to the structured state and then dissociates from IscS to transfer the Fe-S to a [...]

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

Iron-sulfur cluster assembly scaffold protein; A scaffold on which IscS assembles Fe-S clusters. Exists as 2 interconverting forms, a structured (S) and disordered (D) form. The D- state is the preferred substrate for IscS. Converts to the S-state when an Fe-S cluster is assembled, which helps it dissociate from IscS to transfer the Fe-S to an acceptor. It is likely that Fe-S cluster coordination is flexible as the role of this complex is to build and then hand off Fe-S clusters; Belongs to the NifU family.

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

tRNA(Gln,Lys,Glu) U34 2-thiouridylase; Catalyzes the 2-thiolation of uridine at the wobble position (U34) of tRNA(Lys), tRNA(Glu) and tRNA(Gln), leading to the formation of s(2)U34, the first step of tRNA-mnm(5)s(2)U34 synthesis. Sulfur is provided by IscS, via a sulfur-relay system. Binds ATP and its substrate tRNAs.

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

Molybdopterin synthase, small subunit; Involved in sulfur transfer in the conversion of molybdopterin precursor Z to molybdopterin. Belongs to the MoaD family.

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

Molybdopterin synthase, large subunit; Converts molybdopterin precursor Z to molybdopterin. This requires the incorporation of two sulfur atoms into precursor Z to generate a dithiolene group. The sulfur is provided by MoaD.

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

Molybdopterin synthase sulfurylase; Catalyzes the adenylation by ATP of the carboxyl group of the C-terminal glycine of sulfur carrier protein MoaD.

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

mnm(5)-s(2)U34-tRNA 2-thiolation sulfurtransferase; Sulfur carrier protein involved in sulfur trafficking in the cell. Part of a sulfur-relay system required for 2-thiolation during synthesis of 2-thiouridine of the modified wobble base 5- methylaminomethyl-2-thiouridine (mnm(5)s(2)U) in tRNA. Interacts with IscS and stimulates its cysteine desulfurase activity. Accepts an activated sulfur from IscS, which is then transferred to TusD, and thus determines the direction of sulfur flow from IscS to 2-thiouridine formation. Also appears to be involved in sulfur transfer for the biosynthesi [...]

Cysteine sulfinate desulfinase; Catalyzes the removal of elemental sulfur and selenium atoms from L-cysteine, L-cystine, L-selenocysteine, and L-selenocystine to produce L-alanine, and transiently retains the released sulfur atom on a cysteine residue, in the form of a persulfide. Can also desulfinate L-cysteine sulfinate, which is the best substrate of the enzyme. Functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Seems to participate in Fe/S biogenesis by recruiting the SufBCD-SufE proteins. Transfers sulfur to CsdE that increases the cys [...]

mnm(5)-s(2)U34-tRNA 2-thiolation sulfurtransferase; Part of a sulfur-relay system required for 2-thiolation of 5- methylaminomethyl-2-thiouridine (mnm(5)s(2)U) at tRNA wobble positions. Could accept sulfur from TusD.

N-acetylserine-responsive cysteine regulon transcriptional activator; This protein is a positive regulator of gene expression for the cysteine regulon, a system of 10 or more loci involved in the biosynthesis of L-cysteine from inorganic sulfate. The inducer for CysB is N-acetylserine. CysB inhibits its own transcription.

Sulfite reductase, alpha subunit, flavoprotein; Component of the sulfite reductase complex that catalyzes the 6-electron reduction of sulfite to sulfide. This is one of several activities required for the biosynthesis of L-cysteine from sulfate. The flavoprotein component catalyzes the electron flow from NADPH -> FAD -> FMN to the hemoprotein component; In the N-terminal section; belongs to the flavodoxin family.

Sulfite reductase, alpha subunit, flavoprotein; Component of the sulfite reductase complex that catalyzes the 6-electron reduction of sulfite to sulfide. This is one of several activities required for the biosynthesis of L-cysteine from sulfate. The flavoprotein component catalyzes the electron flow from NADPH -> FAD -> FMN to the hemoprotein component; In the N-terminal section; belongs to the flavodoxin family.

N-acetylserine-responsive cysteine regulon transcriptional activator; This protein is a positive regulator of gene expression for the cysteine regulon, a system of 10 or more loci involved in the biosynthesis of L-cysteine from inorganic sulfate. The inducer for CysB is N-acetylserine. CysB inhibits its own transcription.

Sulfite reductase, alpha subunit, flavoprotein; Component of the sulfite reductase complex that catalyzes the 6-electron reduction of sulfite to sulfide. This is one of several activities required for the biosynthesis of L-cysteine from sulfate. The flavoprotein component catalyzes the electron flow from NADPH -> FAD -> FMN to the hemoprotein component; In the N-terminal section; belongs to the flavodoxin family.

6-N-hydroxylaminopurine detoxification oxidoreductase; Protein involved in electron carrier activity.

Sulfite reductase, alpha subunit, flavoprotein; Component of the sulfite reductase complex that catalyzes the 6-electron reduction of sulfite to sulfide. This is one of several activities required for the biosynthesis of L-cysteine from sulfate. The flavoprotein component catalyzes the electron flow from NADPH -> FAD -> FMN to the hemoprotein component; In the N-terminal section; belongs to the flavodoxin family.

6-N-hydroxylaminopurine resistance protein.

[2Fe-2S] ferredoxin; Ferredoxin are iron-sulfur proteins that transfer electrons in a wide variety of metabolic reactions. Although the function of this ferredoxin is unknown it is probable that it has a role as a cellular electron transfer protein. Involved in the in vivo assembly of the Fe-S clusters in a wide variety of iron-sulfur proteins.

DnaK-like molecular chaperone specific for IscU; Chaperone involved in the maturation of iron-sulfur cluster- containing proteins. Has a low intrinsic ATPase activity which is markedly stimulated by HscB. Involved in the maturation of IscU; Belongs to the heat shock protein 70 family.

[2Fe-2S] ferredoxin; Ferredoxin are iron-sulfur proteins that transfer electrons in a wide variety of metabolic reactions. Although the function of this ferredoxin is unknown it is probable that it has a role as a cellular electron transfer protein. Involved in the in vivo assembly of the Fe-S clusters in a wide variety of iron-sulfur proteins.

HscA co-chaperone, J domain-containing protein Hsc56; Co-chaperone involved in the maturation of iron-sulfur cluster-containing proteins. Seems to help targeting proteins to be folded toward HscA; Belongs to the HscB family.

[2Fe-2S] ferredoxin; Ferredoxin are iron-sulfur proteins that transfer electrons in a wide variety of metabolic reactions. Although the function of this ferredoxin is unknown it is probable that it has a role as a cellular electron transfer protein. Involved in the in vivo assembly of the Fe-S clusters in a wide variety of iron-sulfur proteins.

Cysteine desulfurase (tRNA sulfurtransferase), PLP-dependent; Master enzyme that delivers sulfur to a number of partners involved in Fe-S cluster assembly, tRNA modification or cofactor biosynthesis. Catalyzes the removal of elemental sulfur from cysteine to produce alanine. Functions as a sulfur delivery protein for Fe-S cluster synthesis onto IscU, an Fe-S scaffold assembly protein, as well as other S acceptor proteins. Preferentially binds to disordered IscU on which the Fe-S is assembled, IscU converts to the structured state and then dissociates from IscS to transfer the Fe-S to a [...]