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 07-SEP-2016, entry version 123. DE RecName: Full=Sulfoquinovosidase {ECO:0000303|PubMed:26878550}; DE Short=SQase {ECO:0000303|PubMed:26878550}; DE EC=3.2.1.- {ECO:0000269|PubMed:26878550}; GN Name=yihQ {ECO:0000303|PubMed:26878550, ECO:0000312|EMBL:AAC76875.1}; GN Synonyms=squQ {ECO:0000312|EcoGene:EG11843}; GN OrderedLocusNames=b3878, JW3849; OS Escherichia coli (strain K12). OC Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacteriales; 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 RT region 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 RP TO 358 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., RA Mau B., 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 RT MG1655 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 RP IN COMPLEXES WITH THE SUBSTRATE ANALOG RP 4-NITROPHENYL-ALPHA-D-SULFOQUINOVOSIDE AND THE INHIBITOR 5FIDOF, RP FUNCTION, CATALYTIC ACTIVITY, BIOPHYSICOCHEMICAL PROPERTIES, ENZYME RP REGULATION, ACTIVE SITE, REACTION MECHANISM, AND MUTAGENESIS OF RP 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 RT diacylglyceride sulfolipids."; RL Nat. Chem. Biol. 12:215-217(2016). CC -!- FUNCTION: Catalyzes the hydrolysis of sulfoquinovosyl CC diacylglycerides (SQDG) to sulfoquinovose (SQ), which is then CC degraded by E.coli through the SQ Embden-Meyerhof-Parnas (SQ-EMP) CC sulfoglycolysis pathway as a source of carbon and sulfur. CC Therefore, is likely involved in the utilization of the CC sulfoquinovose headgroup found in ubiquitous plant sulfolipids. Is CC also able to hydrolyze simple sulfoquinovosides such as 1- CC sulfoquinovosylglycerol (SQGro). Is a retaining glycoside CC hydrolase, since it forms the alpha anomer of SQ CC (PubMed:26878550). Also exhibits some alpha-glucosidase activity CC against alpha-glucosyl fluoride in vitro, although natural CC substrates, such as alpha-glucobioses are scarcely hydrolyzed CC (PubMed:15294295). {ECO:0000269|PubMed:15294295, CC ECO:0000269|PubMed:26878550}. CC -!- CATALYTIC ACTIVITY: An alpha-sulfoquinovosyl diacylglycerol + CC H(2)O = sulfoquinovose + a 1,2-diacylglycerol. CC {ECO:0000269|PubMed:26878550}. CC -!- ENZYME REGULATION: Is inactivated in vitro by the mechanism-based CC inactivator 5-fluoro-beta-L-idopyranosyl fluoride (5FIdoF) that CC yields a covalent glycosyl-enzyme complex with the active site CC nucleophile 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. CC {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 PDBsum; 5AED; -. DR PDBsum; 5AEE; -. DR PDBsum; 5AEG; -. DR ProteinModelPortal; P32138; -. DR SMR; P32138; 309-635. DR BioGrid; 4260866; 11. DR DIP; DIP-12498N; -. DR IntAct; P32138; 1. DR MINT; MINT-1249337; -. 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; 32123259; VBIEscCol129921_3990. DR EchoBASE; EB1789; -. DR EcoGene; EG11843; yihQ. DR eggNOG; ENOG4105CJQ; Bacteria. DR eggNOG; COG1501; LUCA. DR HOGENOM; HOG000064244; -. DR InParanoid; P32138; -. DR KO; K15922; -. DR OMA; HYEDDAR; -. DR PhylomeDB; P32138; -. DR BioCyc; EcoCyc:EG11843-MONOMER; -. DR BioCyc; ECOL316407:JW3849-MONOMER; -. 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:0005975; P:carbohydrate metabolic process; IEA:InterPro. DR InterPro; IPR011013; Gal_mutarotase_SF_dom. DR InterPro; IPR000322; Glyco_hydro_31. DR InterPro; IPR017853; Glycoside_hydrolase_SF. DR Pfam; PF01055; Glyco_hydro_31; 1. DR SUPFAM; SSF51445; SSF51445; 1. DR SUPFAM; SSF74650; SSF74650; 1. PE 1: Evidence at protein level; KW 3D-structure; Complete proteome; Glycosidase; Hydrolase; KW Reference proteome. FT CHAIN 1 678 Sulfoquinovosidase. FT /FTId=PRO_0000185372. FT REGION 301 304 Substrate binding. FT {ECO:0000305|PubMed:26878550}. FT ACT_SITE 405 405 Nucleophile. FT {ECO:0000269|PubMed:26878550}. FT ACT_SITE 408 408 {ECO:0000250|UniProtKB:P31434}. FT ACT_SITE 472 472 Proton donor. FT {ECO:0000305|PubMed:26878550}. FT BINDING 288 288 Substrate. {ECO:0000305|PubMed:26878550}. FT BINDING 537 537 Substrate. {ECO:0000305|PubMed:26878550}. FT MUTAGEN 288 288 Q->E: Loss of catalytic activity against FT para-nitrophenyl alpha-sulfoquinovoside, FT but in contrast to wild-type, possesses a FT very weak alpha-glucosidase activity FT against para-nitrophenyl alpha-D- FT glucopyranoside. FT {ECO:0000269|PubMed:26878550}. FT MUTAGEN 301 301 R->A,E: Loss of catalytic activity. FT {ECO:0000269|PubMed:26878550}. FT MUTAGEN 301 301 R->K: Almost complete loss of catalytic FT activity. {ECO:0000269|PubMed:26878550}. FT MUTAGEN 301 301 R->Q: 13-fold decrease in substrate FT affinity and 4600-fold decrease in FT catalytic activity. FT {ECO:0000269|PubMed:26878550}. FT MUTAGEN 304 304 W->F: Loss of catalytic activity. FT {ECO:0000269|PubMed:26878550}. FT MUTAGEN 405 405 D->A,N: Loss of catalytic activity. FT {ECO:0000269|PubMed:26878550}. FT MUTAGEN 472 472 D->A,N: Loss of catalytic activity. FT {ECO:0000269|PubMed:26878550}. FT CONFLICT 358 358 A -> R (in Ref. 1; AAB03011). FT {ECO:0000305}. FT CONFLICT 517 517 S -> T (in Ref. 1; AAB03011). FT {ECO:0000305}. FT STRAND 9 12 {ECO:0000244|PDB:5AEG}. FT STRAND 13 16 {ECO:0000244|PDB:5AEE}. FT STRAND 19 24 {ECO:0000244|PDB:5AEE}. FT STRAND 27 32 {ECO:0000244|PDB:5AEE}. FT STRAND 34 36 {ECO:0000244|PDB:5AEE}. FT STRAND 38 51 {ECO:0000244|PDB:5AEE}. FT STRAND 54 66 {ECO:0000244|PDB:5AEE}. FT STRAND 69 75 {ECO:0000244|PDB:5AEE}. FT STRAND 78 86 {ECO:0000244|PDB:5AEE}. FT STRAND 89 97 {ECO:0000244|PDB:5AEE}. FT STRAND 103 111 {ECO:0000244|PDB:5AEE}. FT STRAND 116 122 {ECO:0000244|PDB:5AEE}. FT STRAND 129 133 {ECO:0000244|PDB:5AEE}. FT STRAND 144 148 {ECO:0000244|PDB:5AEE}. FT HELIX 162 171 {ECO:0000244|PDB:5AEE}. FT STRAND 183 189 {ECO:0000244|PDB:5AEE}. FT TURN 190 192 {ECO:0000244|PDB:5AEE}. FT STRAND 193 197 {ECO:0000244|PDB:5AEE}. FT STRAND 203 209 {ECO:0000244|PDB:5AEE}. FT STRAND 212 228 {ECO:0000244|PDB:5AEE}. FT HELIX 232 243 {ECO:0000244|PDB:5AEE}. FT HELIX 251 255 {ECO:0000244|PDB:5AEE}. FT STRAND 256 260 {ECO:0000244|PDB:5AEE}. FT HELIX 265 277 {ECO:0000244|PDB:5AEE}. FT STRAND 282 286 {ECO:0000244|PDB:5AEE}. FT HELIX 288 291 {ECO:0000244|PDB:5AEE}. FT STRAND 293 295 {ECO:0000244|PDB:5AEE}. FT STRAND 300 302 {ECO:0000244|PDB:5AEE}. FT TURN 310 312 {ECO:0000244|PDB:5AEE}. FT HELIX 316 325 {ECO:0000244|PDB:5AEE}. FT STRAND 329 334 {ECO:0000244|PDB:5AEE}. FT STRAND 336 339 {ECO:0000244|PDB:5AEE}. FT HELIX 343 351 {ECO:0000244|PDB:5AEE}. FT STRAND 360 362 {ECO:0000244|PDB:5AEE}. FT STRAND 364 367 {ECO:0000244|PDB:5AEG}. FT STRAND 368 375 {ECO:0000244|PDB:5AEE}. FT HELIX 380 393 {ECO:0000244|PDB:5AEE}. FT TURN 394 398 {ECO:0000244|PDB:5AEE}. FT STRAND 400 404 {ECO:0000244|PDB:5AEE}. FT HELIX 422 443 {ECO:0000244|PDB:5AEE}. FT TURN 447 449 {ECO:0000244|PDB:5AEE}. FT STRAND 451 455 {ECO:0000244|PDB:5AEE}. FT HELIX 461 464 {ECO:0000244|PDB:5AEE}. FT STRAND 474 476 {ECO:0000244|PDB:5AEE}. FT TURN 479 481 {ECO:0000244|PDB:5AEE}. FT HELIX 483 485 {ECO:0000244|PDB:5AEE}. FT HELIX 486 495 {ECO:0000244|PDB:5AEE}. FT HELIX 518 528 {ECO:0000244|PDB:5AEE}. FT STRAND 534 536 {ECO:0000244|PDB:5AEE}. FT HELIX 542 544 {ECO:0000244|PDB:5AEE}. FT HELIX 552 567 {ECO:0000244|PDB:5AEE}. FT HELIX 569 582 {ECO:0000244|PDB:5AEE}. FT STRAND 586 588 {ECO:0000244|PDB:5AEE}. FT HELIX 590 592 {ECO:0000244|PDB:5AEE}. FT HELIX 598 602 {ECO:0000244|PDB:5AEE}. FT STRAND 607 609 {ECO:0000244|PDB:5AEE}. FT TURN 610 612 {ECO:0000244|PDB:5AEE}. FT STRAND 613 615 {ECO:0000244|PDB:5AEE}. FT STRAND 624 630 {ECO:0000244|PDB:5AEE}. FT STRAND 635 637 {ECO:0000244|PDB:5AEE}. FT TURN 638 640 {ECO:0000244|PDB:5AEE}. FT STRAND 646 652 {ECO:0000244|PDB:5AEE}. FT STRAND 659 663 {ECO:0000244|PDB:5AEE}. FT HELIX 669 673 {ECO:0000244|PDB:5AEE}. FT HELIX 674 677 {ECO:0000244|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 //