Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Sucrase-isomaltase, intestinal

Gene

SI

Organism
Oryctolagus cuniculus (Rabbit)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Plays an important role in the final stage of carbohydrate digestion. Isomaltase activity is specific for both alpha-1,4- and alpha-1,6-oligosaccharides.

Catalytic activityi

Hydrolysis of sucrose and maltose by an alpha-D-glucosidase-type action.
Hydrolysis of (1->6)-alpha-D-glucosidic linkages in some oligosaccharides produced from starch and glycogen by alpha-amylase, and in isomaltose.

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Binding sitei264SubstrateBy similarity1
Binding sitei388SubstrateBy similarity1
Active sitei505Nucleophile; for isomaltase activity1
Binding sitei588SubstrateBy similarity1
Active sitei604For isomaltase activityBy similarity1
Binding sitei662SubstrateBy similarity1
Active sitei1394Nucleophile; for sucrase activity1
Active sitei1397For sucrase activity1
Active sitei1500Proton donor; for sucrase activityBy similarity1

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Glycosidase, Hydrolase

Enzyme and pathway databases

BRENDAi3.2.1.10. 1749.

Protein family/group databases

CAZyiGH31. Glycoside Hydrolase Family 31.

Names & Taxonomyi

Protein namesi
Recommended name:
Sucrase-isomaltase, intestinal
Cleaved into the following 2 chains:
Gene namesi
Name:SI
OrganismiOryctolagus cuniculus (Rabbit)
Taxonomic identifieri9986 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresLagomorphaLeporidaeOryctolagus
Proteomesi
  • UP000001811 Componenti: Unplaced

Subcellular locationi

Topology

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Topological domaini2 – 12CytoplasmicSequence analysisAdd BLAST11
Transmembranei13 – 32Helical; Signal-anchor for type II membrane proteinSequence analysisAdd BLAST20
Topological domaini33 – 1827LumenalSequence analysisAdd BLAST1795

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Membrane

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Initiator methionineiRemoved
ChainiPRO_00000185562 – 1827Sucrase-isomaltase, intestinalAdd BLAST1826
ChainiPRO_00000185572 – 1007IsomaltaseAdd BLAST1006
ChainiPRO_00000185581008 – 1827SucraseAdd BLAST820

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei7Phosphoserine; by PKABy similarity1
Glycosylationi42N-linked (GlcNAc...)Sequence analysis1
Disulfide bondi63 ↔ 94PROSITE-ProRule annotation
Disulfide bondi77 ↔ 93PROSITE-ProRule annotation
Disulfide bondi88 ↔ 106PROSITE-ProRule annotation
Glycosylationi99N-linked (GlcNAc...)Sequence analysis1
Modified residuei391SulfotyrosineSequence analysis1
Modified residuei400SulfotyrosineSequence analysis1
Glycosylationi455N-linked (GlcNAc...)Sequence analysis1
Disulfide bondi520 ↔ 545PROSITE-ProRule annotation
Disulfide bondi635 ↔ 646PROSITE-ProRule annotation
Glycosylationi859N-linked (GlcNAc...)Sequence analysis1
Glycosylationi896N-linked (GlcNAc...)Sequence analysis1
Glycosylationi904N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1002N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1235N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1303N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1325N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1340N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1354N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1368N-linked (GlcNAc...)Sequence analysis1
Modified residuei1382SulfotyrosineSequence analysis1
Modified residuei1385SulfotyrosineSequence analysis1
Glycosylationi1403N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1535N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1572N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1748N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1763N-linked (GlcNAc...)Sequence analysis1
Glycosylationi1799N-linked (GlcNAc...)Sequence analysis1

Post-translational modificationi

The precursor is proteolytically cleaved when exposed to pancreatic proteases in the intestinal lumen.
N- and O-glycosylated.
Sulfated.By similarity

Keywords - PTMi

Disulfide bond, Glycoprotein, Phosphoprotein, Sulfation

Proteomic databases

PRIDEiP07768.

Interactioni

Subunit structurei

The resulting sucrase and isomaltase subunits stay associated with one another in a complex by non-covalent linkages.

Protein-protein interaction databases

STRINGi9986.ENSOCUP00000003372.

Structurei

3D structure databases

ProteinModelPortaliP07768.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini61 – 110P-type 1PROSITE-ProRule annotationAdd BLAST50
Domaini932 – 978P-type 2PROSITE-ProRule annotationAdd BLAST47

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni110 – 1007IsomaltaseAdd BLAST898
Regioni1008 – 1827SucraseAdd BLAST820

Compositional bias

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Compositional biasi43 – 60Ser/Thr-richAdd BLAST18

Sequence similaritiesi

Belongs to the glycosyl hydrolase 31 family.Curated
Contains 2 P-type (trefoil) domains.PROSITE-ProRule annotation

Keywords - Domaini

Repeat, Signal-anchor, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiKOG1065. Eukaryota.
COG1501. LUCA.
HOGENOMiHOG000067936.
HOVERGENiHBG080721.
InParanoidiP07768.
KOiK01203.

Family and domain databases

CDDicd00111. Trefoil. 2 hits.
Gene3Di4.10.110.10. 2 hits.
InterProiIPR031727. Gal_mutarotase_N.
IPR011013. Gal_mutarotase_SF_dom.
IPR000322. Glyco_hydro_31.
IPR030458. Glyco_hydro_31_AS.
IPR030459. Glyco_hydro_31_CS.
IPR017853. Glycoside_hydrolase_SF.
IPR017957. P_trefoil_CS.
IPR000519. P_trefoil_dom.
[Graphical view]
PfamiPF01055. Glyco_hydro_31. 2 hits.
PF16863. NtCtMGAM_N. 2 hits.
PF00088. Trefoil. 2 hits.
[Graphical view]
SMARTiSM00018. PD. 2 hits.
[Graphical view]
SUPFAMiSSF51445. SSF51445. 4 hits.
SSF57492. SSF57492. 1 hit.
SSF74650. SSF74650. 2 hits.
PROSITEiPS00129. GLYCOSYL_HYDROL_F31_1. 2 hits.
PS00707. GLYCOSYL_HYDROL_F31_2. 2 hits.
PS00025. P_TREFOIL_1. 1 hit.
PS51448. P_TREFOIL_2. 2 hits.
[Graphical view]

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

P07768-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MAKRKFSGLE ITLIVLFVIV FIIAIALIAV LATKTPAVEE VNPSSSTPTT
60 70 80 90 100
TSTTTSTSGS VSCPSELNEV VNERINCIPE QSPTQAICAQ RNCCWRPWNN
110 120 130 140 150
SDIPWCFFVD NHGYNVEGMT TTSTGLEARL NRKSTPTLFG NDINNVLLTT
160 170 180 190 200
ESQTANRLRF KLTDPNNKRY EVPHQFVTEF AGPAATETLY DVQVTENPFS
210 220 230 240 250
IKVIRKSNNR ILFDSSIGPL VYSDQYLQIS TRLPSEYMYG FGEHVHKRFR
260 270 280 290 300
HDLYWKTWPI FTRDQHTDDN NNNLYGHQTF FMCIEDTTGK SFGVFLMNSN
310 320 330 340 350
AMEIFIQPTP IVTYRVIGGI LDFYIFLGDT PEQVVQQYQE LIGRPAMPAY
360 370 380 390 400
WSLGFQLSRW NYNSLDVVKE VVRRNREALI PFDTQVSDID YMEDKKDFTY
410 420 430 440 450
DRVAYNGLPD FVQDLHDHGQ KYVIILDPAI SINRRASGEA YESYDRGNAQ
460 470 480 490 500
NVWVNESDGT TPIVGEVWPG DTVYPDFTSP NCIEWWANEC NIFHQEVNYD
510 520 530 540 550
GLWIDMNEVS SFVQGSNKGC NDNTLNYPPY IPDIVDKLMY SKTLCMDSVQ
560 570 580 590 600
YWGKQYDVHS LYGYSMAIAT ERAVERVFPN KRSFILTRST FAGSGRHAAH
610 620 630 640 650
WLGDNTATWE QMEWSITGML EFGLFGMPLV GADICGFLAE TTEELCRRWM
660 670 680 690 700
QLGAFYPFSR NHNADGFEHQ DPAFFGQDSL LVKSSRHYLN IRYTLLPFLY
710 720 730 740 750
TLFYKAHAFG ETVARPVLHE FYEDTNSWVE DREFLWGPAL LITPVLTQGA
760 770 780 790 800
ETVSAYIPDA VWYDYETGAK RPWRKQRVEM SLPADKIGLH LRGGYIIPIQ
810 820 830 840 850
QPAVTTTASR MNPLGLIIAL NDDNTAVGDF FWDDGETKDT VQNDNYILYT
860 870 880 890 900
FAVSNNNLNI TCTHELYSEG TTLAFQTIKI LGVTETVTQV TVAENNQSMS
910 920 930 940 950
THSNFTYDPS NQVLLIENLN FNLGRNFRVQ WDQTFLESEK ITCYPDADIA
960 970 980 990 1000
TQEKCTQRGC IWDTNTVNPR APECYFPKTD NPYSVSSTQY SPTGITADLQ
1010 1020 1030 1040 1050
LNPTRTRITL PSEPITNLRV EVKYHKNDMV QFKIFDPQNK RYEVPVPLDI
1060 1070 1080 1090 1100
PATPTSTQEN RLYDVEIKEN PFGIQIRRRS TGKVIWDSCL PGFAFNDQFI
1110 1120 1130 1140 1150
QISTRLPSEY IYGFGEAEHT AFKRDLNWHT WGMFTRDQPP GYKLNSYGFH
1160 1170 1180 1190 1200
PYYMALEDEG NAHGVLLLNS NAMDVTFMPT PALTYRVIGG ILDFYMFLGP
1210 1220 1230 1240 1250
TPEVATQQYH EVIGHPVMPP YWSLGFQLCR YGYRNTSEII ELYEGMVAAD
1260 1270 1280 1290 1300
IPYDVQYTDI DYMERQLDFT IDENFRELPQ FVDRIRGEGM RYIIILDPAI
1310 1320 1330 1340 1350
SGNETRPYPA FDRGEAKDVF VKWPNTSDIC WAKVWPDLPN ITIDESLTED
1360 1370 1380 1390 1400
EAVNASRAHA AFPDFFRNST AEWWTREILD FYNNYMKFDG LWIDMNEPSS
1410 1420 1430 1440 1450
FVNGTTTNVC RNTELNYPPY FPELTKRTDG LHFRTMCMET EHILSDGSSV
1460 1470 1480 1490 1500
LHYDVHNLYG WSQAKPTYDA LQKTTGKRGI VISRSTYPTA GRWAGHWLGD
1510 1520 1530 1540 1550
NYARWDNMDK SIIGMMEFSL FGISYTGADI CGFFNDSEYH LCTRWTQLGA
1560 1570 1580 1590 1600
FYPFARNHNI QFTRRQDPVS WNQTFVEMTR NVLNIRYTLL PYFYTQLHEI
1610 1620 1630 1640 1650
HAHGGTVIRP LMHEFFDDRT TWDIFLQFLW GPAFMVTPVL EPYTTVVRGY
1660 1670 1680 1690 1700
VPNARWFDYH TGEDIGIRGQ VQDLTLLMNA INLHVRGGHI LPCQEPARTT
1710 1720 1730 1740 1750
FLSRQKYMKL IVAADDNHMA QGSLFWDDGD TIDTYERDLY LSVQFNLNKT
1760 1770 1780 1790 1800
TLTSTLLKTG YINKTEIRLG YVHVWGIGNT LINEVNLMYN EINYPLIFNQ
1810 1820
TQAQEILNID LTAHEVTLDD PIEISWS
Length:1,827
Mass (Da):210,140
Last modified:January 23, 2007 - v3
Checksum:i2CEFFE3109AC8917
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M14046 mRNA. Translation: AAA31459.1.
PIRiA23945.
RefSeqiNP_001075735.1. NM_001082266.1.
UniGeneiOcu.1958.

Genome annotation databases

GeneIDi100009093.
KEGGiocu:100009093.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M14046 mRNA. Translation: AAA31459.1.
PIRiA23945.
RefSeqiNP_001075735.1. NM_001082266.1.
UniGeneiOcu.1958.

3D structure databases

ProteinModelPortaliP07768.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

STRINGi9986.ENSOCUP00000003372.

Protein family/group databases

CAZyiGH31. Glycoside Hydrolase Family 31.

Proteomic databases

PRIDEiP07768.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

GeneIDi100009093.
KEGGiocu:100009093.

Organism-specific databases

CTDi6476.

Phylogenomic databases

eggNOGiKOG1065. Eukaryota.
COG1501. LUCA.
HOGENOMiHOG000067936.
HOVERGENiHBG080721.
InParanoidiP07768.
KOiK01203.

Enzyme and pathway databases

BRENDAi3.2.1.10. 1749.

Family and domain databases

CDDicd00111. Trefoil. 2 hits.
Gene3Di4.10.110.10. 2 hits.
InterProiIPR031727. Gal_mutarotase_N.
IPR011013. Gal_mutarotase_SF_dom.
IPR000322. Glyco_hydro_31.
IPR030458. Glyco_hydro_31_AS.
IPR030459. Glyco_hydro_31_CS.
IPR017853. Glycoside_hydrolase_SF.
IPR017957. P_trefoil_CS.
IPR000519. P_trefoil_dom.
[Graphical view]
PfamiPF01055. Glyco_hydro_31. 2 hits.
PF16863. NtCtMGAM_N. 2 hits.
PF00088. Trefoil. 2 hits.
[Graphical view]
SMARTiSM00018. PD. 2 hits.
[Graphical view]
SUPFAMiSSF51445. SSF51445. 4 hits.
SSF57492. SSF57492. 1 hit.
SSF74650. SSF74650. 2 hits.
PROSITEiPS00129. GLYCOSYL_HYDROL_F31_1. 2 hits.
PS00707. GLYCOSYL_HYDROL_F31_2. 2 hits.
PS00025. P_TREFOIL_1. 1 hit.
PS51448. P_TREFOIL_2. 2 hits.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiSUIS_RABIT
AccessioniPrimary (citable) accession number: P07768
Entry historyi
Integrated into UniProtKB/Swiss-Prot: August 1, 1988
Last sequence update: January 23, 2007
Last modified: October 5, 2016
This is version 124 of the entry and version 3 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Miscellaneous

There is a high degree of homology between the isomaltase and sucrase portions (41% of amino acid identity) indicating that this protein is evolved by partial gene duplication.

Keywords - Technical termi

Complete proteome, Direct protein sequencing, Multifunctional enzyme, Reference proteome

Documents

  1. Glycosyl hydrolases
    Classification of glycosyl hydrolase families and list of entries
  2. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.