| IED ID | IndEnz0002011730 |
| Enzyme Type ID | protease011730 |
| Protein Name |
Cytotoxin-L EC 3.4.22.- Lethal toxin LT Cleaved into: Glucosyltransferase TcsL EC 2.4.1.- |
| Gene Name | tcsL |
| Organism | Paeniclostridium sordellii (Clostridium sordellii) |
| Taxonomic Lineage | cellular organisms Bacteria Terrabacteria group Firmicutes Clostridia Eubacteriales Peptostreptococcaceae Paeniclostridium Paeniclostridium sordellii (Clostridium sordellii) |
| Enzyme Sequence | MNLVNKAQLQKMVYVKFRIQEDEYVAILNALEEYHNMSESSVVEKYLKLKDINNLTDNYLNTYKKSGRNKALKKFKEYLTMEVLELKNNSLTPVEKNLHFIWIGGQINDTAINYINQWKDVNSDYTVKVFYDSNAFLINTLKKTIVESATNNTLESFRENLNDPEFDYNKFYRKRMEIIYDKQKHFIDYYKSQIEENPEFIIDNIIKTYLSNEYSKDLEALNKYIEESLNKITANNGNDIRNLEKFADEDLVRLYNQELVERWNLAAASDILRISMLKEDGGVYLDVDILPGIQPDLFKSINKPDSITNTSWEMIKLEAIMKYKEYIPGYTSKNFDMLDEEVQRSFESALSSKSDKSEIFLPLDDIKVSPLEVKIAFANNSVINQALISLKDSYCSDLVINQIKNRYKILNDNLNPSINEGTDFNTTMKIFSDKLASISNEDNMMFMIKITNYLKVGFAPDVRSTINLSGPGVYTGAYQDLLMFKDNSTNIHLLEPELRNFEFPKTKISQLTEQEITSLWSFNQARAKSQFEEYKKGYFEGALGEDDNLDFAQNTVLDKDYVSKKILSSMKTRNKEYIHYIVQLQGDKISYEASCNLFSKDPYSSILYQKNIEGSETAYYYYVADAEIKEIDKYRIPYQISNKRNIKLTFIGHGKSEFNTDTFANLDVDSLSSEIETILNLAKADISPKYIEINLLGCNMFSYSISAEETYPGKLLLKIKDRVSELMPSISQDSITVSANQYEVRINEEGKREILDHSGKWINKEESIIKDISSKEYISFNPKENKIIVKSKYLHELSTLLQEIRNNANSSDIDLEKKVMLTECEINVASNIDRQIVEGRIEEAKNLTSDSINYIKNEFKLIESISDSLYDLKHQNGLDDSHFISFEDISKTENGFRIRFINKETGNSIFIETEKEIFSEYATHISKEISNIKDTIFDNVNGKLVKKVNLDAAHEVNTLNSAFFIQSLIEYNTTKESLSNLSVAMKVQVYAQLFSTGLNTITDASKVVELVSTALDETIDLLPTLSEGLPIIATIIDGVSLGAAIKELSETNDPLLRQEIEAKIGIMAVNLTAASTAIVTSALGIASGFSILLVPLAGISAGIPSLVNNELILQDKATKVIDYFKHISLAETEGAFTLLDDKIIMPQDDLVLSEIDFNNNSITLGKCEIWRAEGGSGHTLTDDIDHFFSSPSITYRKPWLSIYDVLNIKKEKIDFSKDLMVLPNAPNRVFGYEMGWTPGFRSLDNDGTKLLDRIRDHYEGQFYWRYFAFIADALITKLKPRYEDTNVRINLDGNTRSFIVPVITTEQIRKNLSYSFYGSGGSYSLSLSPYNMNIDLNLVENDTWVIDVDNVVKNITIESDEIQKGELIENILSKLNIEDNKIILNNHTINFYGDINESNRFISLTFSILEDINIIIEIDLVSKSYKILLSGNCMKLIENSSDIQQKIDHIGFNGEHQKYIPYSYIDNETKYNGFIDYSKKEGLFTAEFSNESIIRNIYMPDSNNLFIYSSKDLKDIRIINKGDVKLLIGNYFKDDMKVSLSFTIEDTNTIKLNGVYLDENGVAQILKFMNNAKSALNTSNSLMNFLESINIKNIFYNNLDPNIEFILDTNFIISGSNSIGQFELICDKDKNIQPYFINFKIKETSYTLYVGNRQNLIVEPSYHLDDSGNISSTVINFSQKYLYGIDRYVNKVIIAPNLYTDEINITPVYKPNYICPEVIILDANYINEKINVNINDLSIRYVWDNDGSDLILIANSEEDNQPQVKIRFVNVFKSDTAADKLSFNFSDKQDVSVSKIISTFSLAAYSDGFFDYEFGLVSLDNDYFYINSFGNMVSGLIYINDSLYYFKPPKNNLITGFTTIDGNKYYFDPTKSGAASIGEITIDGKDYYFNKQGILQVGVINTSDGLKYFAPAGTLDENLEGESVNFIGKLNIDGKIYYFEDNYRAAVEWKLLDDETYYFNPKTGEALKGLHQIGDNKYYFDDNGIMQTGFITINDKVFYFNNDGVMQVGYIEVNGKYFYFGKNGERQLGVFNTPDGFKFFGPKDDDLGTEEGELTLYNGILNFNGKIYFFDISNTAVVGWGTLDDGSTYYFDDNRAEACIGLTVINDCKYYFDDNGIRQLGFITINDNIFYFSESGKIELGYQNINGNYFYIDESGLVLIGVFDTPDGYKYFAPLNTVNDNIYGQAVKYSGLVRVNEDVYYFGETYKIETGWIENETDKYYFDPETKKAYKGINVVDDIKYYFDENGIMRTGLISFENNNYYFNEDGKMQFGYLNIKDKMFYFGKDGKMQIGVFNTPDGFKYFAHQNTLDENFEGESINYTGWLDLDGKRYYFTDEYIAATGSLTIDGYNYYFDPDTAELVVSE |
| Enzyme Length | 2364 |
| Uniprot Accession Number | Q46342 |
| Absorption | |
| Active Site | ACT_SITE 653; /note="For protease activity"; /evidence="ECO:0000255|PROSITE-ProRule:PRU01107"; ACT_SITE 698; /note="Nucleophile; for protease activity"; /evidence="ECO:0000255|PROSITE-ProRule:PRU01107, ECO:0000305|PubMed:27303685" |
| Activity Regulation | ACTIVITY REGULATION: [Cytotoxin-L]: Protease activity is activated upon binding to 1D-myo-inositol hexakisphosphate (InsP6), which induces conformational reorganization. {ECO:0000269|PubMed:17334356}. |
| Binding Site | BINDING 139; /note="UDP-alpha-D-glucose"; /evidence="ECO:0000269|PubMed:18325534, ECO:0000269|PubMed:18505687, ECO:0007744|PDB:2VKD, ECO:0007744|PDB:2VKH, ECO:0007744|PDB:2VL8"; BINDING 577; /note="1D-myo-inositol hexakisphosphate"; /evidence="ECO:0000250|UniProtKB:P16154"; BINDING 600; /note="1D-myo-inositol hexakisphosphate"; /evidence="ECO:0000250|UniProtKB:P16154"; BINDING 647; /note="1D-myo-inositol hexakisphosphate"; /evidence="ECO:0000250|UniProtKB:P16154"; BINDING 764; /note="1D-myo-inositol hexakisphosphate"; /evidence="ECO:0000250|UniProtKB:P16154"; BINDING 775; /note="1D-myo-inositol hexakisphosphate"; /evidence="ECO:0000250|UniProtKB:P16154"; BINDING 792; /note="1D-myo-inositol hexakisphosphate"; /evidence="ECO:0000250|UniProtKB:P16154" |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: [Glucosyltransferase TcsL]: Reaction=L-threonyl-[protein] + UDP-alpha-D-glucose = 3-O-(alpha-D-glucosyl)-L-threonyl-[protein] + H(+) + UDP; Xref=Rhea:RHEA:64684, Rhea:RHEA-COMP:11060, Rhea:RHEA-COMP:16656, ChEBI:CHEBI:15378, ChEBI:CHEBI:30013, ChEBI:CHEBI:58223, ChEBI:CHEBI:58885, ChEBI:CHEBI:156085; Evidence={ECO:0000269|PubMed:17901056, ECO:0000269|PubMed:19744486, ECO:0000269|PubMed:24905543, ECO:0000269|PubMed:24919149, ECO:0000269|PubMed:27023605, ECO:0000269|PubMed:27303685, ECO:0000269|PubMed:30622517, ECO:0000269|PubMed:8626575, ECO:0000269|PubMed:8626586, ECO:0000269|PubMed:8858106, ECO:0000269|PubMed:9632667};PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:64685; Evidence={ECO:0000269|PubMed:17901056, ECO:0000269|PubMed:19744486, ECO:0000269|PubMed:24905543, ECO:0000269|PubMed:24919149, ECO:0000269|PubMed:27023605, ECO:0000269|PubMed:27303685, ECO:0000269|PubMed:30622517, ECO:0000269|PubMed:8626575, ECO:0000269|PubMed:8626586, ECO:0000269|PubMed:8858106, ECO:0000269|PubMed:9632667}; |
| DNA Binding | |
| EC Number | 3.4.22.-; 2.4.1.- |
| Enzyme Function | FUNCTION: [Cytotoxin-L]: Precursor of a cytotoxin that targets the vascular endothelium, inducing an anti-inflammatory effect and resulting in lethal toxic shock syndrome (PubMed:19527792, PubMed:24919149, PubMed:29146177). TcsL constitutes the main toxin that mediates the pathology of P.sordellii infection, an anaerobic Gram-positive bacterium found in soil and in the gastrointestinal and vaginal tracts of animals and humans; although the majority of carriers are asymptomatic, pathogenic P.sordellii infections arise rapidly and are highly lethal (PubMed:29146177). This form constitutes the precursor of the toxin: it enters into host cells and mediates autoprocessing to release the active toxin (Glucosyltransferase TcsL) into the host cytosol (PubMed:32302524, PubMed:17334356, PubMed:27303685). Targets vascular endothelium by binding to the semaphorin proteins SEMA6A and SEMA6B, and enters host cells via clathrin-mediated endocytosis (PubMed:32302524). Once entered into host cells, acidification in the endosome promotes the membrane insertion of the translocation region and formation of a pore, leading to translocation of the GT44 and peptidase C80 domains across the endosomal membrane (By similarity). This activates the peptidase C80 domain and autocatalytic processing, releasing the N-terminal part (Glucosyltransferase TcsL), which constitutes the active part of the toxin, in the cytosol (PubMed:17334356, PubMed:27303685). {ECO:0000250|UniProtKB:P18177, ECO:0000269|PubMed:17334356, ECO:0000269|PubMed:19527792, ECO:0000269|PubMed:24919149, ECO:0000269|PubMed:27303685, ECO:0000269|PubMed:32302524, ECO:0000303|PubMed:29146177}.; FUNCTION: [Glucosyltransferase TcsL]: Active form of the toxin, which is released into the host cytosol following autoprocessing and inactivates small GTPases (PubMed:8626575, PubMed:8626586, PubMed:9632667, PubMed:17901056, PubMed:19744486, PubMed:24905543, PubMed:24919149, PubMed:27303685, PubMed:27023605, PubMed:30622517). Acts by mediating monoglucosylation of small GTPases of the Ras (H-Ras/HRAS, K-Ras/KRAS, N-Ras/NRAS and Ral/RALA) family in host cells at the conserved threonine residue located in the switch I region ('Thr-37/35'), using UDP-alpha-D-glucose as the sugar donor (PubMed:8858106, PubMed:8626575, PubMed:8626586, PubMed:9632667, PubMed:17901056, PubMed:19744486, PubMed:24905543, PubMed:24919149, PubMed:27023605, PubMed:30622517). Also able to catalyze monoglucosylation of some members of the Rho family (Rac1 and Rap2A), but with less efficiency than with Ras proteins (PubMed:8626586, PubMed:9632667, PubMed:19744486, PubMed:24905543). Monoglucosylation of host small GTPases completely prevents the recognition of the downstream effector, blocking the GTPases in their inactive form and leading to apoptosis (PubMed:8626586, PubMed:9632667, PubMed:17910886). Induces an anti-inflammatory effect, mainly by inactivating Ras proteins which results in blockage of the cell cycle and killing of immune cells (PubMed:17910886, PubMed:24919149). The absence or moderate local inflammatory response allows C.sordellii spreading in deep tissues, production of toxin which is released in the general circulation and causes a toxic shock syndrome (PubMed:24919149, PubMed:29146177). {ECO:0000269|PubMed:17901056, ECO:0000269|PubMed:17910886, ECO:0000269|PubMed:19744486, ECO:0000269|PubMed:24905543, ECO:0000269|PubMed:24919149, ECO:0000269|PubMed:27023605, ECO:0000269|PubMed:27303685, ECO:0000269|PubMed:30622517, ECO:0000269|PubMed:8626575, ECO:0000269|PubMed:8626586, ECO:0000269|PubMed:8858106, ECO:0000269|PubMed:9632667, ECO:0000303|PubMed:29146177}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Active site (2); Beta strand (8); Binding site (7); Chain (2); Domain (2); Helix (28); Metal binding (7); Mutagenesis (14); Region (14); Repeat (20); Site (1); Turn (5) |
| Keywords | 3D-structure;Autocatalytic cleavage;Glycosyltransferase;Host cell membrane;Host cytoplasm;Host endosome;Host membrane;Hydrolase;Lipid-binding;Magnesium;Manganese;Membrane;Metal-binding;Protease;Repeat;Secreted;Thiol protease;Toxin;Transferase;Virulence;Zinc |
| Interact With | |
| Induction | |
| Subcellular Location | SUBCELLULAR LOCATION: [Cytotoxin-L]: Secreted {ECO:0000250|UniProtKB:P18177}. Host endosome membrane {ECO:0000250|UniProtKB:P18177}. Note=Secreted from P.sordellii cell into the extracellular environment via help of holin-like protein TcdE/UtxA (By similarity). Binds to the cell surface receptors via the receptor-binding region and enters the cells via clathrin-mediated endocytosis (By similarity). Acidification in the endosome triggers conformational changes that promote the membrane insertion of the translocation region, allowing formation of a pore, leading to translocation of the GT44 and peptidase C80 domains across the endosomal membrane (By similarity). 1D-myo-inositol hexakisphosphate-binding (InsP6) activates the peptidase C80 domain and autoprocessing, generating the Glucosyltransferase TcsL form, which is released in the host cytosol (PubMed:17334356). {ECO:0000250|UniProtKB:P18177, ECO:0000269|PubMed:17334356}.; SUBCELLULAR LOCATION: [Glucosyltransferase TcsL]: Host cytoplasm, host cytosol {ECO:0000305|PubMed:8626586}. Host cell membrane {ECO:0000269|PubMed:27023605, ECO:0000269|PubMed:27303685}; Peripheral membrane protein {ECO:0000269|PubMed:27023605}; Cytoplasmic side {ECO:0000269|PubMed:27023605}. Note=Binding to phospholipids, such as phosphatidylserine and phosphatidic acid promotes localization to the inner face of the cell membrane close to its membrane anchored substrates (small GTPases). {ECO:0000269|PubMed:25882477, ECO:0000269|PubMed:27023605}. |
| Modified Residue | |
| Post Translational Modification | PTM: [Cytotoxin-L]: Undergoes autocatalytic cleavage to release the N-terminal part (Glucosyltransferase TcsL), which constitutes the active part of the toxin, in the host cytosol (PubMed:17334356, PubMed:27303685). 1D-myo-inositol hexakisphosphate-binding (InsP6) activates the peptidase C80 domain and promotes autoprocessing (PubMed:17334356). {ECO:0000269|PubMed:17334356, ECO:0000269|PubMed:27303685}. |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (3) |
| Cross Reference PDB | 2VKD; 2VKH; 2VL8; |
| Mapped Pubmed ID | - |
| Motif | |
| Gene Encoded By | |
| Mass | 270,580 |
| Kinetics | |
| Metal Binding | METAL 288; /note="Magnesium or manganese"; /evidence="ECO:0000269|PubMed:18325534, ECO:0007744|PDB:2VKD, ECO:0007744|PDB:2VKH"; METAL 515; /note="Magnesium or manganese"; /evidence="ECO:0000269|PubMed:18325534, ECO:0007744|PDB:2VKD, ECO:0007744|PDB:2VKH"; METAL 518; /note="Magnesium or manganese"; /evidence="ECO:0000269|PubMed:18325534, ECO:0000269|PubMed:18505687, ECO:0007744|PDB:2VKH, ECO:0007744|PDB:2VL8"; METAL 545; /note="Zinc; via carbonyl oxygen"; /evidence="ECO:0000250|UniProtKB:P16154"; METAL 546; /note="Zinc"; /evidence="ECO:0000250|UniProtKB:P18177"; METAL 653; /note="Zinc"; /evidence="ECO:0000250|UniProtKB:P18177"; METAL 757; /note="Zinc"; /evidence="ECO:0000250|UniProtKB:P18177" |
| Rhea ID | RHEA:64684; RHEA:64685 |
| Cross Reference Brenda | 2.4.1.B62; |