ID SQASE_ECOLI Reviewed; 678 AA. AC P32138; P76775; Q2M8H5; DT 01-OCT-1993, integrated into UniProtKB/Swiss-Prot. DT 15-JUL-1998, sequence version 3. DT 13-SEP-2023, entry version 158. DE RecName: Full=Sulfoquinovosidase {ECO:0000303|PubMed:26878550}; DE Short=SQase {ECO:0000303|PubMed:26878550}; DE EC=3.2.1.199 {ECO:0000269|PubMed:26878550}; GN Name=yihQ {ECO:0000303|PubMed:26878550, ECO:0000312|EMBL:AAC76875.1}; GN Synonyms=squQ; OrderedLocusNames=b3878, JW3849; OS Escherichia coli (strain K12). OC Bacteria; Pseudomonadota; Gammaproteobacteria; Enterobacterales; OC Enterobacteriaceae; Escherichia. OX NCBI_TaxID=83333; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=K12 / MG1655 / ATCC 47076; RX PubMed=8346018; DOI=10.1093/nar/21.15.3391; RA Plunkett G. III, Burland V., Daniels D.L., Blattner F.R.; RT "Analysis of the Escherichia coli genome. III. DNA sequence of the region RT from 87.2 to 89.2 minutes."; RL Nucleic Acids Res. 21:3391-3398(1993). RN [2] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA], AND SEQUENCE REVISION TO 358 RP AND 517. RC STRAIN=K12 / MG1655 / ATCC 47076; RX PubMed=9278503; DOI=10.1126/science.277.5331.1453; RA Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V., RA Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F., RA Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B., RA Shao Y.; RT "The complete genome sequence of Escherichia coli K-12."; RL Science 277:1453-1462(1997). RN [3] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911; RX PubMed=16738553; DOI=10.1038/msb4100049; RA Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., RA Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T.; RT "Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 RT and W3110."; RL Mol. Syst. Biol. 2:E1-E5(2006). RN [4] RP FUNCTION. RX PubMed=15294295; DOI=10.1016/j.pep.2004.05.008; RA Okuyama M., Mori H., Chiba S., Kimura A.; RT "Overexpression and characterization of two unknown proteins, YicI and RT YihQ, originated from Escherichia coli."; RL Protein Expr. Purif. 37:170-179(2004). RN [5] RP IDENTIFICATION BY MASS SPECTROMETRY, INDUCTION, AND PATHWAY. RC STRAIN=K12; RX PubMed=24463506; DOI=10.1038/nature12947; RA Denger K., Weiss M., Felux A.K., Schneider A., Mayer C., Spiteller D., RA Huhn T., Cook A.M., Schleheck D.; RT "Sulphoglycolysis in Escherichia coli K-12 closes a gap in the RT biogeochemical sulphur cycle."; RL Nature 507:114-117(2014). RN [6] RP X-RAY CRYSTALLOGRAPHY (1.85 ANGSTROMS) OF WILD-TYPE AND MUTANT ASN-472 IN RP COMPLEXES WITH THE SUBSTRATE ANALOG 4-NITROPHENYL-ALPHA-D-SULFOQUINOVOSIDE RP AND THE INHIBITOR 5FIDOF, FUNCTION, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL RP PROPERTIES, ACTIVITY REGULATION, ACTIVE SITE, REACTION MECHANISM, AND RP MUTAGENESIS OF ARG-301; TRP-304; ASP-405 AND ASP-472. RC STRAIN=K12 / DH5-alpha; RX PubMed=26878550; DOI=10.1038/nchembio.2023; RA Speciale G., Jin Y., Davies G.J., Williams S.J., Goddard-Borger E.D.; RT "YihQ is a sulfoquinovosidase that cleaves sulfoquinovosyl diacylglyceride RT sulfolipids."; RL Nat. Chem. Biol. 12:215-217(2016). CC -!- FUNCTION: Catalyzes the hydrolysis of sulfoquinovosyl diacylglycerides CC (SQDG) to sulfoquinovose (SQ), which is then degraded by E.coli through CC the SQ Embden-Meyerhof-Parnas (SQ-EMP) sulfoglycolysis pathway as a CC source of carbon and sulfur. Therefore, is likely involved in the CC utilization of the sulfoquinovose headgroup found in ubiquitous plant CC sulfolipids. Is also able to hydrolyze simple sulfoquinovosides such as CC 1-sulfoquinovosylglycerol (SQGro). Is a retaining glycoside hydrolase, CC since it forms the alpha anomer of SQ (PubMed:26878550). Also exhibits CC some alpha-glucosidase activity against alpha-glucosyl fluoride in CC vitro, although natural substrates, such as alpha-glucobioses are CC scarcely hydrolyzed (PubMed:15294295). {ECO:0000269|PubMed:15294295, CC ECO:0000269|PubMed:26878550}. CC -!- CATALYTIC ACTIVITY: CC Reaction=a 6-sulfo-alpha-D-quinovosyldiacylglycerol + H2O = 6-sulfo- CC alpha-D-quinovose + a 1,2-diacyl-sn-glycerol; Xref=Rhea:RHEA:49452, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:17815, ChEBI:CHEBI:131487, CC ChEBI:CHEBI:142956; EC=3.2.1.199; CC Evidence={ECO:0000269|PubMed:26878550}; CC -!- ACTIVITY REGULATION: Is inactivated in vitro by the mechanism-based CC inactivator 5-fluoro-beta-L-idopyranosyl fluoride (5FIdoF) that yields CC a covalent glycosyl-enzyme complex with the active site nucleophile CC Asp-405. {ECO:0000269|PubMed:26878550}. CC -!- BIOPHYSICOCHEMICAL PROPERTIES: CC Kinetic parameters: CC KM=0.22 mM for para-nitrophenyl alpha-sulfoquinovoside CC {ECO:0000269|PubMed:26878550}; CC Note=kcat is 14.3 sec(-1) with para-nitrophenyl alpha- CC sulfoquinovoside as substrate. {ECO:0000269|PubMed:26878550}; CC pH dependence: CC Optimum pH is 6. {ECO:0000269|PubMed:26878550}; CC -!- PATHWAY: Glycolipid metabolism. {ECO:0000305|PubMed:24463506}. CC -!- INDUCTION: Induced during growth with sulfoquinovose. CC {ECO:0000269|PubMed:24463506}. CC -!- SIMILARITY: Belongs to the glycosyl hydrolase 31 family. {ECO:0000305}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; L19201; AAB03011.1; -; Genomic_DNA. DR EMBL; U00096; AAC76875.1; -; Genomic_DNA. DR EMBL; AP009048; BAE77431.1; -; Genomic_DNA. DR PIR; A65193; A65193. DR RefSeq; NP_418314.1; NC_000913.3. DR RefSeq; WP_000380843.1; NZ_LN832404.1. DR PDB; 5AED; X-ray; 1.91 A; A/B=1-678. DR PDB; 5AEE; X-ray; 1.85 A; A/B=1-678. DR PDB; 5AEG; X-ray; 1.85 A; A/B=1-678. DR PDB; 5OHT; X-ray; 1.87 A; A/B=1-678. DR PDBsum; 5AED; -. DR PDBsum; 5AEE; -. DR PDBsum; 5AEG; -. DR PDBsum; 5OHT; -. DR AlphaFoldDB; P32138; -. DR SMR; P32138; -. DR BioGRID; 4260866; 11. DR DIP; DIP-12498N; -. DR IntAct; P32138; 1. DR STRING; 511145.b3878; -. DR CAZy; GH31; Glycoside Hydrolase Family 31. DR PaxDb; P32138; -. DR EnsemblBacteria; AAC76875; AAC76875; b3878. DR EnsemblBacteria; BAE77431; BAE77431; BAE77431. DR GeneID; 948376; -. DR KEGG; ecj:JW3849; -. DR KEGG; eco:b3878; -. DR PATRIC; fig|1411691.4.peg.2833; -. DR EchoBASE; EB1789; -. DR eggNOG; COG1501; Bacteria. DR HOGENOM; CLU_017110_0_1_6; -. DR InParanoid; P32138; -. DR OMA; CLTYSSE; -. DR OrthoDB; 176168at2; -. DR PhylomeDB; P32138; -. DR BioCyc; EcoCyc:EG11843-MONOMER; -. DR BioCyc; MetaCyc:EG11843-MONOMER; -. DR BRENDA; 3.2.1.199; 2026. DR SABIO-RK; P32138; -. DR PRO; PR:P32138; -. DR Proteomes; UP000000318; Chromosome. DR Proteomes; UP000000625; Chromosome. DR GO; GO:0030246; F:carbohydrate binding; IEA:InterPro. DR GO; GO:0004553; F:hydrolase activity, hydrolyzing O-glycosyl compounds; IEA:InterPro. DR GO; GO:1990929; F:sulfoquinovosidase activity; IDA:EcoCyc. DR GO; GO:0061720; P:6-sulfoquinovose(1-) catabolic process to glycerone phosphate and 3-sulfolactaldehyde; IDA:EcoCyc. DR GO; GO:0005975; P:carbohydrate metabolic process; IEA:InterPro. DR CDD; cd06594; GH31_glucosidase_YihQ; 1. DR CDD; cd14752; GH31_N; 1. DR Gene3D; 3.20.20.80; Glycosidases; 1. DR Gene3D; 2.60.40.1760; glycosyl hydrolase (family 31); 1. DR Gene3D; 2.60.40.1180; Golgi alpha-mannosidase II; 1. DR InterPro; IPR011013; Gal_mutarotase_sf_dom. DR InterPro; IPR000322; Glyco_hydro_31. DR InterPro; IPR013780; Glyco_hydro_b. DR InterPro; IPR017853; Glycoside_hydrolase_SF. DR InterPro; IPR044112; YihQ-like. DR PANTHER; PTHR46959; SULFOQUINOVOSIDASE; 1. DR PANTHER; PTHR46959:SF2; SULFOQUINOVOSIDASE; 1. DR Pfam; PF01055; Glyco_hydro_31; 1. DR SUPFAM; SSF51445; (Trans)glycosidases; 1. DR SUPFAM; SSF74650; Galactose mutarotase-like; 1. DR SUPFAM; SSF51011; Glycosyl hydrolase domain; 1. PE 1: Evidence at protein level; KW 3D-structure; Glycosidase; Hydrolase; Reference proteome. FT CHAIN 1..678 FT /note="Sulfoquinovosidase" FT /id="PRO_0000185372" FT ACT_SITE 405 FT /note="Nucleophile" FT /evidence="ECO:0000269|PubMed:26878550" FT ACT_SITE 408 FT /evidence="ECO:0000250|UniProtKB:P31434" FT ACT_SITE 472 FT /note="Proton donor" FT /evidence="ECO:0000305|PubMed:26878550" FT BINDING 288 FT /ligand="substrate" FT /evidence="ECO:0000305|PubMed:26878550" FT BINDING 301..304 FT /ligand="substrate" FT /evidence="ECO:0000305|PubMed:26878550" FT BINDING 537 FT /ligand="substrate" FT /evidence="ECO:0000305|PubMed:26878550" FT MUTAGEN 288 FT /note="Q->E: Loss of catalytic activity against para- FT nitrophenyl alpha-sulfoquinovoside, but in contrast to FT wild-type, possesses a very weak alpha-glucosidase activity FT against para-nitrophenyl alpha-D-glucopyranoside." FT /evidence="ECO:0000269|PubMed:26878550" FT MUTAGEN 301 FT /note="R->A,E: Loss of catalytic activity." FT /evidence="ECO:0000269|PubMed:26878550" FT MUTAGEN 301 FT /note="R->K: Almost complete loss of catalytic activity." FT /evidence="ECO:0000269|PubMed:26878550" FT MUTAGEN 301 FT /note="R->Q: 13-fold decrease in substrate affinity and FT 4600-fold decrease in catalytic activity." FT /evidence="ECO:0000269|PubMed:26878550" FT MUTAGEN 304 FT /note="W->F: Loss of catalytic activity." FT /evidence="ECO:0000269|PubMed:26878550" FT MUTAGEN 405 FT /note="D->A,N: Loss of catalytic activity." FT /evidence="ECO:0000269|PubMed:26878550" FT MUTAGEN 472 FT /note="D->A,N: Loss of catalytic activity." FT /evidence="ECO:0000269|PubMed:26878550" FT CONFLICT 358 FT /note="A -> R (in Ref. 1; AAB03011)" FT /evidence="ECO:0000305" FT CONFLICT 517 FT /note="S -> T (in Ref. 1; AAB03011)" FT /evidence="ECO:0000305" FT STRAND 9..12 FT /evidence="ECO:0007829|PDB:5AEG" FT STRAND 13..16 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 19..24 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 27..32 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 34..36 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 38..51 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 54..66 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 69..75 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 78..86 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 89..97 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 103..111 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 116..122 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 129..133 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 144..148 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 162..171 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 183..189 FT /evidence="ECO:0007829|PDB:5AEE" FT TURN 190..192 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 193..197 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 203..209 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 212..228 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 232..243 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 251..255 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 256..260 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 265..277 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 282..286 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 288..291 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 293..295 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 300..302 FT /evidence="ECO:0007829|PDB:5AEE" FT TURN 310..312 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 316..325 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 329..334 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 336..339 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 343..351 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 360..362 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 364..367 FT /evidence="ECO:0007829|PDB:5AEG" FT STRAND 368..375 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 380..393 FT /evidence="ECO:0007829|PDB:5AEE" FT TURN 394..398 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 400..404 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 422..443 FT /evidence="ECO:0007829|PDB:5AEE" FT TURN 447..449 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 451..455 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 461..464 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 474..476 FT /evidence="ECO:0007829|PDB:5AEE" FT TURN 479..481 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 483..485 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 486..495 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 518..528 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 534..536 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 542..544 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 552..567 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 569..582 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 586..588 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 590..592 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 598..602 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 607..609 FT /evidence="ECO:0007829|PDB:5AEE" FT TURN 610..612 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 613..615 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 624..630 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 635..637 FT /evidence="ECO:0007829|PDB:5AEE" FT TURN 638..640 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 646..652 FT /evidence="ECO:0007829|PDB:5AEE" FT STRAND 659..663 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 669..673 FT /evidence="ECO:0007829|PDB:5AEE" FT HELIX 674..677 FT /evidence="ECO:0007829|PDB:5AEE" SQ SEQUENCE 678 AA; 77275 MW; 85869F52BB72FEE7 CRC64; MDTPRPQLLD FQFHQNNDSF TLHFQQRLIL THSKDNPCLW IGSGIADIDM FRGNFSIKDK LQEKIALTDA IVSQSPDGWL IHFSRGSDIS ATLNISADDQ GRLLLELQND NLNHNRIWLR LAAQPEDHIY GCGEQFSYFD LRGKPFPLWT SEQGVGRNKQ TYVTWQADCK ENAGGDYYWT FFPQPTFVST QKYYCHVDNS CYMNFDFSAP EYHELALWED KATLRFECAD TYISLLEKLT ALLGRQPELP DWIYDGVTLG IQGGTEVCQK KLDTMRNAGV KVNGIWAQDW SGIRMTSFGK RVMWNWKWNS ENYPQLDSRI KQWNQEGVQF LAYINPYVAS DKDLCEEAAQ HGYLAKDASG GDYLVEFGEF YGGVVDLTNP EAYAWFKEVI KKNMIELGCG GWMADFGEYL PTDTYLHNGV SAEIMHNAWP ALWAKCNYEA LEETGKLGEI LFFMRAGSTG SQKYSTMMWA GDQNVDWSLD DGLASVVPAA LSLAMTGHGL HHSDIGGYTT LFEMKRSKEL LLRWCDFSAF TPMMRTHEGN RPGDNWQFDG DAETIAHFAR MTTVFTTLKP YLKEAVALNA KSGLPVMRPL FLHYEDDAHT YTLKYQYLLG RDILVAPVHE EGRSDWTLYL PEDNWVHAWT GEAFRGGEVT VNAPIGKPPV FYRADSEWAA LFASLKSI //