UniProtKB - P0A6B7 (ISCS_ECOLI)
Protein
Cysteine desulfurase IscS
Gene
iscS
Organism
Escherichia coli (strain K12)
Status
Functioni
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 an acceptor protein. Also functions as a selenium delivery protein in the pathway for the biosynthesis of selenophosphate. Transfers sulfur onto 'Cys-456' of ThiI and onto 'Cys-19' of TusA in transpersulfidation reactions.10 Publications
Catalytic activityi
- EC:2.8.1.7UniRule annotation1 Publication
Cofactori
pyridoxal 5'-phosphateUniRule annotation2 Publications
Activity regulationi
Treatment with N-ethylmaleimide inhibits sulfur transfer. Activated by ThiI and TusA.3 Publications
Kineticsi
kcat is 8.5 min(-1).1 Publication
- KM=2.7 µM for L-cysteine1 Publication
: iron-sulfur cluster biosynthesis Pathwayi
This protein is involved in the pathway iron-sulfur cluster biosynthesis, which is part of Cofactor biosynthesis.UniRule annotation1 PublicationView all proteins of this organism that are known to be involved in the pathway iron-sulfur cluster biosynthesis and in Cofactor biosynthesis.
Sites
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Binding sitei | 155 | Pyridoxal phosphateUniRule annotation | 1 | |
Binding sitei | 183 | Pyridoxal phosphateUniRule annotation1 Publication | 1 | |
Binding sitei | 243 | Pyridoxal phosphateUniRule annotation1 Publication | 1 | |
Active sitei | 328 | Cysteine persulfide intermediateUniRule annotation2 Publications | 1 | |
Metal bindingi | 328 | Iron-sulfur (2Fe-2S); via persulfide group; shared with IscUUniRule annotation | 1 |
GO - Molecular functioni
- 2 iron, 2 sulfur cluster binding Source: UniProtKB-UniRule
- cysteine desulfurase activity Source: EcoCyc
- metal ion binding Source: UniProtKB-KW
- pyridoxal phosphate binding Source: EcoCyc
- selenocysteine lyase activity Source: EcoCyc
- sulfur carrier activity Source: EcoCyc
GO - Biological processi
- [2Fe-2S] cluster assembly Source: UniProtKB-UniRule
- iron-sulfur cluster assembly Source: EcoCyc
- oxazole or thiazole biosynthetic process Source: EcoCyc
- tRNA pseudouridine synthesis Source: EcoCyc
Keywordsi
Molecular function | Transferase |
Biological process | tRNA processing |
Ligand | 2Fe-2S, Iron, Iron-sulfur, Metal-binding, Pyridoxal phosphate |
Enzyme and pathway databases
BioCyci | EcoCyc:G7325-MONOMER MetaCyc:G7325-MONOMER |
UniPathwayi | UPA00266 |
Names & Taxonomyi
Protein namesi | Recommended name: Cysteine desulfurase IscS1 PublicationUniRule annotation (EC:2.8.1.7UniRule annotation1 Publication)Alternative name(s): NifS protein homolog1 Publication ThiI transpersulfidase1 Publication TusA transpersulfidase1 Publication |
Gene namesi | Name:iscSUniRule annotation Synonyms:nuvC, yfhO, yzzO Ordered Locus Names:b2530, JW2514 |
Organismi | Escherichia coli (strain K12) |
Taxonomic identifieri | 83333 [NCBI] |
Taxonomic lineagei | Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacterales › Enterobacteriaceae › Escherichia › |
Proteomesi |
|
Subcellular locationi
Cytoplasm and Cytosol
- Cytoplasm UniRule annotationCurated
Cytosol
- cytosol Source: EcoCyc
Keywords - Cellular componenti
CytoplasmPathology & Biotechi
Disruption phenotypei
Cells lacking this gene lose sulfurtransferase activity and require thiamine and nicotinic acid for growth. Under aerobic conditions the deletion of IscS causes an auxotrophy for thiamine and nicotinic acid, whereas under anaerobic conditions, only nicotinic acid s required.2 Publications
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 328 | C → A: Loss of cysteine desulfurization. 1 Publication | 1 | |
Mutagenesisi | 376 – 404 | Missing : Normal cysteine desulfurase activity, decreased binding to IscU, decreased sulfur transfer to IscU, decreased Fe-S cluster assembly. 1 PublicationAdd BLAST | 29 |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
ChainiPRO_0000150264 | 1 – 404 | Cysteine desulfurase IscSAdd BLAST | 404 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Modified residuei | 206 | N6-(pyridoxal phosphate)lysineUniRule annotation1 Publication | 1 |
Proteomic databases
jPOSTi | P0A6B7 |
PaxDbi | P0A6B7 |
PRIDEi | P0A6B7 |
Interactioni
Subunit structurei
Homodimer. The homodimer interacts with IscU and TusA, other S acceptors. Each subunit of the IscS dimer contacts a IscU monomer.
4 PublicationsBinary interactionsi
Hide detailsP0A6B7
Protein-protein interaction databases
BioGRIDi | 4263511, 579 interactors 851343, 3 interactors |
ComplexPortali | CPX-2136, L-cysteine desulfurase complex CPX-2139, IscS-TusA complex CPX-2140, IscS-ThiL complex CPX-2141, IscS-IscU complex |
DIPi | DIP-29109N |
IntActi | P0A6B7, 47 interactors |
MINTi | P0A6B7 |
STRINGi | 511145.b2530 |
Structurei
Secondary structure
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details3D structure databases
SASBDBi | P0A6B7 |
SMRi | P0A6B7 |
ModBasei | Search... |
PDBe-KBi | Search... |
Miscellaneous databases
EvolutionaryTracei | P0A6B7 |
Family & Domainsi
Region
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Regioni | 75 – 76 | Pyridoxal phosphate bindingUniRule annotation | 2 | |
Regioni | 203 – 205 | Pyridoxal phosphate bindingUniRule annotation1 Publication | 3 |
Domaini
The C-terminus (residues 376-404) is important for interaction with IscU.1 Publication
Sequence similaritiesi
Belongs to the class-V pyridoxal-phosphate-dependent aminotransferase family. NifS/IscS subfamily.UniRule annotation
Phylogenomic databases
eggNOGi | COG1104, Bacteria |
HOGENOMi | CLU_003433_0_2_6 |
InParanoidi | P0A6B7 |
PhylomeDBi | P0A6B7 |
Family and domain databases
Gene3Di | 3.40.640.10, 1 hit 3.90.1150.10, 1 hit |
HAMAPi | MF_00331, Cys_desulf_IscS, 1 hit |
InterProi | View protein in InterPro IPR000192, Aminotrans_V_dom IPR020578, Aminotrans_V_PyrdxlP_BS IPR010240, Cys_deSase_IscS IPR016454, Cysteine_dSase IPR015424, PyrdxlP-dep_Trfase IPR015422, PyrdxlP-dep_Trfase_dom1 IPR015421, PyrdxlP-dep_Trfase_major |
PANTHERi | PTHR11601:SF34, PTHR11601:SF34, 1 hit |
Pfami | View protein in Pfam PF00266, Aminotran_5, 1 hit |
PIRSFi | PIRSF005572, NifS, 1 hit |
SUPFAMi | SSF53383, SSF53383, 1 hit |
TIGRFAMsi | TIGR02006, IscS, 1 hit |
PROSITEi | View protein in PROSITE PS00595, AA_TRANSFER_CLASS_5, 1 hit |
i Sequence
Sequence statusi: Complete.
P0A6B7-1 [UniParc]FASTAAdd to basket
10 20 30 40 50
MKLPIYLDYS ATTPVDPRVA EKMMQFMTMD GTFGNPASRS HRFGWQAEEA
60 70 80 90 100
VDIARNQIAD LVGADPREIV FTSGATESDN LAIKGAANFY QKKGKHIITS
110 120 130 140 150
KTEHKAVLDT CRQLEREGFE VTYLAPQRNG IIDLKELEAA MRDDTILVSI
160 170 180 190 200
MHVNNEIGVV QDIAAIGEMC RARGIIYHVD ATQSVGKLPI DLSQLKVDLM
210 220 230 240 250
SFSGHKIYGP KGIGALYVRR KPRVRIEAQM HGGGHERGMR SGTLPVHQIV
260 270 280 290 300
GMGEAYRIAK EEMATEMERL RGLRNRLWNG IKDIEEVYLN GDLEHGAPNI
310 320 330 340 350
LNVSFNYVEG ESLIMALKDL AVSSGSACTS ASLEPSYVLR ALGLNDELAH
360 370 380 390 400
SSIRFSLGRF TTEEEIDYTI ELVRKSIGRL RDLSPLWEMY KQGVDLNSIE
WAHH
Experimental Info
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Sequence conflicti | 31 | G → D AA sequence (PubMed:8663056).Curated | 1 | |
Sequence conflicti | 34 | G → F AA sequence (PubMed:8663056).Curated | 1 | |
Sequence conflicti | 37 – 38 | AS → NA AA sequence (PubMed:8663056).Curated | 2 | |
Sequence conflicti | 118 | G → L AA sequence (PubMed:8663056).Curated | 1 | |
Sequence conflicti | 126 | P → M AA sequence (PubMed:8663056).Curated | 1 | |
Sequence conflicti | 320 | L → I AA sequence (PubMed:8663056).Curated | 1 | |
Sequence conflicti | 326 – 327 | SA → YL AA sequence (PubMed:8663056).Curated | 2 | |
Sequence conflicti | 339 | L → V AA sequence (PubMed:8663056).Curated | 1 |
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U00096 Genomic DNA Translation: AAT48142.1 AP009048 Genomic DNA Translation: BAA16424.1 |
RefSeqi | WP_001295373.1, NZ_STEB01000011.1 YP_026169.1, NC_000913.3 |
Genome annotation databases
EnsemblBacteriai | AAT48142; AAT48142; b2530 BAA16424; BAA16424; BAA16424 |
GeneIDi | 58390229 947004 |
KEGGi | ecj:JW2514 eco:b2530 |
PATRICi | fig|1411691.4.peg.4204 |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U00096 Genomic DNA Translation: AAT48142.1 AP009048 Genomic DNA Translation: BAA16424.1 |
RefSeqi | WP_001295373.1, NZ_STEB01000011.1 YP_026169.1, NC_000913.3 |
3D structure databases
Select the link destinations: PDBei RCSB PDBi PDBji Links Updated | PDB entry | Method | Resolution (Å) | Chain | Positions | PDBsum |
1P3W | X-ray | 2.10 | A/B | 1-404 | [»] | |
SASBDBi | P0A6B7 | |||||
SMRi | P0A6B7 | |||||
ModBasei | Search... | |||||
PDBe-KBi | Search... |
Protein-protein interaction databases
BioGRIDi | 4263511, 579 interactors 851343, 3 interactors |
ComplexPortali | CPX-2136, L-cysteine desulfurase complex CPX-2139, IscS-TusA complex CPX-2140, IscS-ThiL complex CPX-2141, IscS-IscU complex |
DIPi | DIP-29109N |
IntActi | P0A6B7, 47 interactors |
MINTi | P0A6B7 |
STRINGi | 511145.b2530 |
Proteomic databases
jPOSTi | P0A6B7 |
PaxDbi | P0A6B7 |
PRIDEi | P0A6B7 |
Genome annotation databases
EnsemblBacteriai | AAT48142; AAT48142; b2530 BAA16424; BAA16424; BAA16424 |
GeneIDi | 58390229 947004 |
KEGGi | ecj:JW2514 eco:b2530 |
PATRICi | fig|1411691.4.peg.4204 |
Organism-specific databases
EchoBASEi | EB2542 |
Phylogenomic databases
eggNOGi | COG1104, Bacteria |
HOGENOMi | CLU_003433_0_2_6 |
InParanoidi | P0A6B7 |
PhylomeDBi | P0A6B7 |
Enzyme and pathway databases
UniPathwayi | UPA00266 |
BioCyci | EcoCyc:G7325-MONOMER MetaCyc:G7325-MONOMER |
Miscellaneous databases
EvolutionaryTracei | P0A6B7 |
PROi | PR:P0A6B7 |
Family and domain databases
Gene3Di | 3.40.640.10, 1 hit 3.90.1150.10, 1 hit |
HAMAPi | MF_00331, Cys_desulf_IscS, 1 hit |
InterProi | View protein in InterPro IPR000192, Aminotrans_V_dom IPR020578, Aminotrans_V_PyrdxlP_BS IPR010240, Cys_deSase_IscS IPR016454, Cysteine_dSase IPR015424, PyrdxlP-dep_Trfase IPR015422, PyrdxlP-dep_Trfase_dom1 IPR015421, PyrdxlP-dep_Trfase_major |
PANTHERi | PTHR11601:SF34, PTHR11601:SF34, 1 hit |
Pfami | View protein in Pfam PF00266, Aminotran_5, 1 hit |
PIRSFi | PIRSF005572, NifS, 1 hit |
SUPFAMi | SSF53383, SSF53383, 1 hit |
TIGRFAMsi | TIGR02006, IscS, 1 hit |
PROSITEi | View protein in PROSITE PS00595, AA_TRANSFER_CLASS_5, 1 hit |
ProtoNeti | Search... |
MobiDBi | Search... |
Entry informationi
Entry namei | ISCS_ECOLI | |
Accessioni | P0A6B7Primary (citable) accession number: P0A6B7 Secondary accession number(s): P39171 Q8XA86 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | June 7, 2005 |
Last sequence update: | June 7, 2005 | |
Last modified: | April 7, 2021 | |
This is version 140 of the entry and version 1 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Prokaryotic Protein Annotation Program |
Miscellaneousi
Keywords - Technical termi
3D-structure, Direct protein sequencing, Reference proteomeDocuments
- PATHWAY comments
Index of metabolic and biosynthesis pathways - PDB cross-references
Index of Protein Data Bank (PDB) cross-references - SIMILARITY comments
Index of protein domains and families