ID SIAP_HAEIN Reviewed; 329 AA.
AC P44542;
DT 01-NOV-1995, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1995, sequence version 1.
DT 27-MAR-2024, entry version 136.
DE RecName: Full=Sialic acid-binding periplasmic protein SiaP;
DE AltName: Full=Extracytoplasmic solute receptor protein SiaP;
DE AltName: Full=N-acetylneuraminic-binding protein;
DE AltName: Full=Neu5Ac-binding protein;
DE Flags: Precursor;
GN Name=siaP; OrderedLocusNames=HI_0146;
OS Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd).
OC Bacteria; Pseudomonadota; Gammaproteobacteria; Pasteurellales;
OC Pasteurellaceae; Haemophilus.
OX NCBI_TaxID=71421;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=ATCC 51907 / DSM 11121 / KW20 / Rd;
RX PubMed=7542800; DOI=10.1126/science.7542800;
RA Fleischmann R.D., Adams M.D., White O., Clayton R.A., Kirkness E.F.,
RA Kerlavage A.R., Bult C.J., Tomb J.-F., Dougherty B.A., Merrick J.M.,
RA McKenney K., Sutton G.G., FitzHugh W., Fields C.A., Gocayne J.D.,
RA Scott J.D., Shirley R., Liu L.-I., Glodek A., Kelley J.M., Weidman J.F.,
RA Phillips C.A., Spriggs T., Hedblom E., Cotton M.D., Utterback T.R.,
RA Hanna M.C., Nguyen D.T., Saudek D.M., Brandon R.C., Fine L.D.,
RA Fritchman J.L., Fuhrmann J.L., Geoghagen N.S.M., Gnehm C.L., McDonald L.A.,
RA Small K.V., Fraser C.M., Smith H.O., Venter J.C.;
RT "Whole-genome random sequencing and assembly of Haemophilus influenzae
RT Rd.";
RL Science 269:496-512(1995).
RN [2]
RP IDENTIFICATION BY MASS SPECTROMETRY.
RC STRAIN=ATCC 51907 / DSM 11121 / KW20 / Rd;
RX PubMed=10675023;
RX DOI=10.1002/(sici)1522-2683(20000101)21:2<411::aid-elps411>3.0.co;2-4;
RA Langen H., Takacs B., Evers S., Berndt P., Lahm H.W., Wipf B., Gray C.,
RA Fountoulakis M.;
RT "Two-dimensional map of the proteome of Haemophilus influenzae.";
RL Electrophoresis 21:411-429(2000).
RN [3]
RP FUNCTION, CHARACTERIZATION, SUBUNIT, AND MASS SPECTROMETRY.
RC STRAIN=ATCC 51907 / DSM 11121 / KW20 / Rd;
RX PubMed=16262798; DOI=10.1111/j.1365-2958.2005.04901.x;
RA Severi E., Randle G., Kivlin P., Whitfield K., Young R., Moxon R.,
RA Kelly D., Hood D., Thomas G.H.;
RT "Sialic acid transport in Haemophilus influenzae is essential for
RT lipopolysaccharide sialylation and serum resistance and is dependent on a
RT novel tripartite ATP-independent periplasmic transporter.";
RL Mol. Microbiol. 58:1173-1185(2005).
RN [4] {ECO:0007744|PDB:2CEX, ECO:0007744|PDB:2CEY}
RP X-RAY CRYSTALLOGRAPHY (1.7 ANGSTROMS) OF 24-329 IN COMPLEX WITH SIALIC ACID
RP ANALOG.
RX PubMed=16702222; DOI=10.1074/jbc.m603463200;
RA Mueller A., Severi E., Mulligan C., Watts A.G., Kelly D.J., Wilson K.S.,
RA Wilkinson A.J., Thomas G.H.;
RT "Conservation of structure and mechanism in primary and secondary
RT transporters exemplified by SiaP, a sialic acid binding virulence factor
RT from Haemophilus influenzae.";
RL J. Biol. Chem. 281:22212-22222(2006).
RN [5] {ECO:0007744|PDB:3B50}
RP X-RAY CRYSTALLOGRAPHY (1.40 ANGSTROMS) OF 24-329 IN COMPLEX WITH
RP N-ACETYL-BETA-NEURAMINATE, FUNCTION, AND MUTAGENESIS OF ASP-72; THR-87;
RP ARG-150 AND ARG-170.
RC STRAIN=NTHi 2019;
RX PubMed=17947229; DOI=10.1074/jbc.m706603200;
RA Johnston J.W., Coussens N.P., Allen S., Houtman J.C., Turner K.H.,
RA Zaleski A., Ramaswamy S., Gibson B.W., Apicella M.A.;
RT "Characterization of the N-acetyl-5-neuraminic acid-binding site of the
RT extracytoplasmic solute receptor (SiaP) of nontypeable Haemophilus
RT influenzae strain 2019.";
RL J. Biol. Chem. 283:855-865(2008).
RN [6] {ECO:0007744|PDB:2XWI, ECO:0007744|PDB:2XWK, ECO:0007744|PDB:2XWO, ECO:0007744|PDB:2XWV}
RP X-RAY CRYSTALLOGRAPHY (1.05 ANGSTROMS) OF 24-329 OF WILD-TYPE AND MUTANTS
RP ALA-170; GLU-170 AND LYS-170 IN COMPLEX WITH N-ACETYL-BETA-NEURAMINATE,
RP FUNCTION, AND MUTAGENESIS OF ARG-170.
RC STRAIN=ATCC 51907 / DSM 11121 / KW20 / Rd;
RX PubMed=26342690; DOI=10.1074/jbc.m115.656603;
RA Fischer M., Hopkins A.P., Severi E., Hawkhead J., Bawdon D., Watts A.G.,
RA Hubbard R.E., Thomas G.H.;
RT "Tripartite ATP-independent Periplasmic (TRAP) Transporters Use an
RT Arginine-mediated Selectivity Filter for High Affinity Substrate Binding.";
RL J. Biol. Chem. 290:27113-27123(2015).
CC -!- FUNCTION: Part of the tripartite ATP-independent periplasmic (TRAP)
CC transport system SiaPT involved in the uptake of sialic acid (N-acetyl-
CC beta-neuraminate). This protein specifically binds sialic acid with
CC high affinity. N-Acetylneuraminate (sialic acid) can then be
CC incorporated into the lipooligosaccharides (LOS) as a terminal non-
CC reducing sugar, protecting the bacterium from complement-mediated
CC killing by normal human serum. {ECO:0000269|PubMed:16262798,
CC ECO:0000269|PubMed:17947229, ECO:0000269|PubMed:26342690}.
CC -!- SUBUNIT: The complex comprises the extracytoplasmic solute receptor
CC protein SiaP, and the fused transmembrane protein SiaT.
CC {ECO:0000269|PubMed:16262798, ECO:0000269|PubMed:16702222}.
CC -!- SUBCELLULAR LOCATION: Periplasm {ECO:0000305}.
CC -!- MASS SPECTROMETRY: Mass=34165; Mass_error=2; Method=Electrospray;
CC Evidence={ECO:0000269|PubMed:16262798};
CC -!- MISCELLANEOUS: Is essential for lipopolysaccharide (LPS) sialylation
CC and serum resistance.
CC -!- SIMILARITY: Belongs to the bacterial solute-binding protein 7 family.
CC {ECO:0000305}.
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DR EMBL; L42023; AAC21818.1; -; Genomic_DNA.
DR PIR; H64143; H64143.
DR RefSeq; NP_438315.1; NC_000907.1.
DR PDB; 2CEX; X-ray; 2.20 A; A/B/C/D=24-329.
DR PDB; 2CEY; X-ray; 1.70 A; A=24-329.
DR PDB; 2V4C; X-ray; 1.70 A; A=24-329.
DR PDB; 2WX9; X-ray; 1.37 A; A=24-329.
DR PDB; 2WYK; X-ray; 1.50 A; A=24-329.
DR PDB; 2WYP; X-ray; 1.50 A; A=24-329.
DR PDB; 2XA5; X-ray; 1.09 A; A=24-329.
DR PDB; 2XWI; X-ray; 2.20 A; A=24-329.
DR PDB; 2XWK; X-ray; 1.49 A; A=24-329.
DR PDB; 2XWO; X-ray; 1.54 A; A=24-329.
DR PDB; 2XWV; X-ray; 1.05 A; A=24-329.
DR PDB; 2XXK; X-ray; 1.48 A; A=24-329.
DR PDB; 3B50; X-ray; 1.40 A; A=24-329.
DR PDB; 6H75; X-ray; 1.45 A; A=24-329.
DR PDB; 6H76; X-ray; 1.50 A; A=24-329.
DR PDBsum; 2CEX; -.
DR PDBsum; 2CEY; -.
DR PDBsum; 2V4C; -.
DR PDBsum; 2WX9; -.
DR PDBsum; 2WYK; -.
DR PDBsum; 2WYP; -.
DR PDBsum; 2XA5; -.
DR PDBsum; 2XWI; -.
DR PDBsum; 2XWK; -.
DR PDBsum; 2XWO; -.
DR PDBsum; 2XWV; -.
DR PDBsum; 2XXK; -.
DR PDBsum; 3B50; -.
DR PDBsum; 6H75; -.
DR PDBsum; 6H76; -.
DR AlphaFoldDB; P44542; -.
DR SMR; P44542; -.
DR STRING; 71421.HI_0146; -.
DR TCDB; 2.A.56.1.3; the tripartite atp-independent periplasmic transporter (trap-t) family.
DR EnsemblBacteria; AAC21818; AAC21818; HI_0146.
DR KEGG; hin:HI_0146; -.
DR PATRIC; fig|71421.8.peg.148; -.
DR eggNOG; COG1638; Bacteria.
DR HOGENOM; CLU_036176_1_1_6; -.
DR OrthoDB; 8690069at2; -.
DR PhylomeDB; P44542; -.
DR BioCyc; HINF71421:G1GJ1-158-MONOMER; -.
DR EvolutionaryTrace; P44542; -.
DR Proteomes; UP000000579; Chromosome.
DR GO; GO:0030288; C:outer membrane-bounded periplasmic space; IEA:InterPro.
DR GO; GO:0008643; P:carbohydrate transport; IEA:UniProtKB-KW.
DR GO; GO:0055085; P:transmembrane transport; IEA:InterPro.
DR CDD; cd13672; PBP2_TRAP_Siap; 1.
DR Gene3D; 3.40.190.170; Bacterial extracellular solute-binding protein, family 7; 1.
DR InterPro; IPR018389; DctP_fam.
DR InterPro; IPR004682; TRAP_DctP.
DR InterPro; IPR038404; TRAP_DctP_sf.
DR NCBIfam; TIGR00787; dctP; 1.
DR NCBIfam; NF037995; TRAP_S1; 1.
DR PANTHER; PTHR33376; -; 1.
DR PANTHER; PTHR33376:SF4; SIALIC ACID-BINDING PERIPLASMIC PROTEIN SIAP; 1.
DR Pfam; PF03480; DctP; 1.
DR PIRSF; PIRSF006470; DctB; 1.
DR SUPFAM; SSF53850; Periplasmic binding protein-like II; 1.
PE 1: Evidence at protein level;
KW 3D-structure; Periplasm; Reference proteome; Signal; Sugar transport;
KW Transport.
FT SIGNAL 1..23
FT /evidence="ECO:0000305"
FT CHAIN 24..329
FT /note="Sialic acid-binding periplasmic protein SiaP"
FT /id="PRO_0000031816"
FT BINDING 33
FT /ligand="N-acetyl-beta-neuraminate"
FT /ligand_id="ChEBI:CHEBI:58705"
FT /evidence="ECO:0000269|PubMed:17947229,
FT ECO:0000269|PubMed:26342690, ECO:0007744|PDB:2XWV,
FT ECO:0007744|PDB:3B50"
FT BINDING 72
FT /ligand="N-acetyl-beta-neuraminate"
FT /ligand_id="ChEBI:CHEBI:58705"
FT /evidence="ECO:0000269|PubMed:17947229,
FT ECO:0000269|PubMed:26342690, ECO:0007744|PDB:2XWV,
FT ECO:0007744|PDB:3B50"
FT BINDING 90
FT /ligand="N-acetyl-beta-neuraminate"
FT /ligand_id="ChEBI:CHEBI:58705"
FT /evidence="ECO:0000269|PubMed:17947229,
FT ECO:0000269|PubMed:26342690, ECO:0007744|PDB:2XWV,
FT ECO:0007744|PDB:3B50"
FT BINDING 150
FT /ligand="N-acetyl-beta-neuraminate"
FT /ligand_id="ChEBI:CHEBI:58705"
FT /evidence="ECO:0000269|PubMed:17947229,
FT ECO:0000269|PubMed:26342690, ECO:0007744|PDB:2XWV,
FT ECO:0007744|PDB:3B50"
FT BINDING 170
FT /ligand="N-acetyl-beta-neuraminate"
FT /ligand_id="ChEBI:CHEBI:58705"
FT /evidence="ECO:0000269|PubMed:17947229,
FT ECO:0000269|PubMed:26342690, ECO:0007744|PDB:2XWV,
FT ECO:0007744|PDB:3B50"
FT BINDING 210
FT /ligand="N-acetyl-beta-neuraminate"
FT /ligand_id="ChEBI:CHEBI:58705"
FT /evidence="ECO:0000269|PubMed:17947229,
FT ECO:0000269|PubMed:26342690, ECO:0007744|PDB:2XWV,
FT ECO:0007744|PDB:3B50"
FT MUTAGEN 72
FT /note="D->A: Complete loss of incorporation of N-acetyl-
FT beta-neuraminate into the LOS."
FT /evidence="ECO:0000269|PubMed:17947229"
FT MUTAGEN 87
FT /note="T->R: Complete loss of incorporation of N-acetyl-
FT beta-neuraminate into the LOS."
FT /evidence="ECO:0000269|PubMed:17947229"
FT MUTAGEN 150
FT /note="R->A: Complete loss of incorporation of N-acetyl-
FT beta-neuraminate into the LOS."
FT /evidence="ECO:0000269|PubMed:17947229"
FT MUTAGEN 150
FT /note="R->K: Reduced incorporation of N-acetyl-beta-
FT neuraminate into the LOS."
FT /evidence="ECO:0000269|PubMed:17947229"
FT MUTAGEN 170
FT /note="R->A,K: Complete loss of incorporation of N-acetyl-
FT beta-neuraminate into the LOS. Large defect in N-acetyl-
FT beta-neuraminate uptake and binding."
FT /evidence="ECO:0000269|PubMed:17947229,
FT ECO:0000269|PubMed:26342690"
FT STRAND 26..31
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 39..54
FT /evidence="ECO:0007829|PDB:2XWV"
FT TURN 55..57
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 58..64
FT /evidence="ECO:0007829|PDB:2XWV"
FT TURN 66..69
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 72..80
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 86..89
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 91..96
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 99..105
FT /evidence="ECO:0007829|PDB:2XWV"
FT TURN 107..109
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 113..121
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 124..137
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 139..156
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 161..164
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 168..171
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 175..184
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 187..190
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 193..195
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 196..201
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 204..211
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 212..217
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 220..222
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 225..228
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 234..242
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 243..246
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 251..285
FT /evidence="ECO:0007829|PDB:2XWV"
FT STRAND 289..291
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 296..301
FT /evidence="ECO:0007829|PDB:2XWV"
FT HELIX 303..325
FT /evidence="ECO:0007829|PDB:2XWV"
SQ SEQUENCE 329 AA; 36513 MW; 4E369E0D51DA5F93 CRC64;
MMKLTKLFLA TAISLGVSSA VLAADYDLKF GMNAGTSSNE YKAAEMFAKE VKEKSQGKIE
ISLYPSSQLG DDRAMLKQLK DGSLDFTFAE SARFQLFYPE AAVFALPYVI SNYNVAQKAL
FDTEFGKDLI KKMDKDLGVT LLSQAYNGTR QTTSNRAINS IADMKGLKLR VPNAATNLAY
AKYVGASPTP MAFSEVYLAL QTNAVDGQEN PLAAVQAQKF YEVQKFLAMT NHILNDQLYL
VSNETYKELP EDLQKVVKDA AENAAKYHTK LFVDGEKDLV TFFEKQGVKI THPDLVPFKE
SMKPYYAEFV KQTGQKGESA LKQIEAINP
//
