ID   GSPG_VIBCH              Reviewed;         146 AA.
AC   P45773; Q9JPZ6;
DT   01-NOV-1995, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1995, sequence version 1.
DT   02-SEP-2026, entry version 135.
DE   RecName: Full=Type II secretion system core protein G;
DE            Short=T2SS core protein G;
DE   AltName: Full=Cholera toxin secretion protein EpsG;
DE   AltName: Full=General secretion pathway protein G;
DE   Flags: Precursor;
GN   Name=epsG; OrderedLocusNames=VC_2730;
OS   Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961).
OC   Bacteria; Pseudomonadati; Pseudomonadota; Gammaproteobacteria; Vibrionales;
OC   Vibrionaceae; Vibrio.
OX   NCBI_TaxID=243277;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC   STRAIN=El Tor TRH7000;
RA   Overbye L.J.;
RT   "Organization of the general secretion pathway genes in Vibrio cholerae.";
RL   Thesis (1994), Michigan State University, United States.
RN   [2]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 39315 / El Tor Inaba N16961;
RX   PubMed=10952301; DOI=10.1038/35020000;
RA   Heidelberg J.F., Eisen J.A., Nelson W.C., Clayton R.A., Gwinn M.L.,
RA   Dodson R.J., Haft D.H., Hickey E.K., Peterson J.D., Umayam L.A., Gill S.R.,
RA   Nelson K.E., Read T.D., Tettelin H., Richardson D.L., Ermolaeva M.D.,
RA   Vamathevan J.J., Bass S., Qin H., Dragoi I., Sellers P., McDonald L.A.,
RA   Utterback T.R., Fleischmann R.D., Nierman W.C., White O., Salzberg S.L.,
RA   Smith H.O., Colwell R.R., Mekalanos J.J., Venter J.C., Fraser C.M.;
RT   "DNA sequence of both chromosomes of the cholera pathogen Vibrio
RT   cholerae.";
RL   Nature 406:477-483(2000).
RN   [3]
RP   FUNCTION, INTERACTION WITH ESPL, AND MUTAGENESIS OF ASP-100 AND THR-121.
RX   PubMed=21255118; DOI=10.1111/j.1365-2958.2010.07487.x;
RA   Gray M.D., Bagdasarian M., Hol W.G., Sandkvist M.;
RT   "In vivo cross-linking of EpsG to EpsL suggests a role for EpsL as an
RT   ATPase-pseudopilin coupling protein in the Type II secretion system of
RT   Vibrio cholerae.";
RL   Mol. Microbiol. 79:786-798(2011).
RN   [4]
RP   INDUCTION BY CYCLIC DI-GMP AND VPSR.
RX   PubMed=28674069; DOI=10.1128/jb.00106-17;
RA   Sloup R.E., Konal A.E., Severin G.B., Korir M.L., Bagdasarian M.M.,
RA   Bagdasarian M., Waters C.M.;
RT   "Cyclic Di-GMP and VpsR Induce the Expression of Type II Secretion in
RT   Vibrio cholerae.";
RL   J. Bacteriol. 199:0-0(2017).
CC   -!- FUNCTION: Core component of the type II secretion system required for
CC       the energy-dependent secretion of extracellular factors such as
CC       proteases and toxins from the periplasm (PubMed:21255118). Pseudopilin
CC       (pilin-like) protein that polymerizes to form the pseudopilus. Further
CC       polymerization triggers pseudopilus growth (By similarity).
CC       {ECO:0000250|UniProtKB:Q00514, ECO:0000269|PubMed:21255118}.
CC   -!- SUBUNIT: Type II secretion system is composed of four main components:
CC       the outer membrane complex, the inner membrane complex, the cytoplasmic
CC       secretion ATPase and the periplasm-spanning pseudopilus. Forms
CC       homomultimers (By similarity). Interacts with EspL (PubMed:21255118).
CC       {ECO:0000250|UniProtKB:Q00514, ECO:0000269|PubMed:21255118}.
CC   -!- SUBCELLULAR LOCATION: Cell inner membrane
CC       {ECO:0000250|UniProtKB:Q00514}; Single-pass membrane protein
CC       {ECO:0000255}.
CC   -!- INDUCTION: By cyclic di-GMP and VpsR. {ECO:0000269|PubMed:28674069}.
CC   -!- PTM: Cleaved by the prepilin peptidase. {ECO:0000250|UniProtKB:Q00514}.
CC   -!- PTM: Methylated by prepilin peptidase at the amino group of the N-
CC       terminal phenylalanine once the leader sequence is cleaved.
CC       {ECO:0000250|UniProtKB:Q00514}.
CC   -!- SIMILARITY: Belongs to the GSP G family. {ECO:0000305}.
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DR   EMBL; L33796; AAA58788.1; -; Genomic_DNA.
DR   EMBL; AE003852; AAF95870.1; -; Genomic_DNA.
DR   PIR; D82041; D82041.
DR   RefSeq; WP_000738789.1; NC_002505.1.
DR   PDB; 3FU1; X-ray; 1.90 A; A/B=35-146.
DR   PDB; 4LW9; X-ray; 1.90 A; A/B/C/D/E/F/I/J/K/L/Q/R=35-146.
DR   AlphaFoldDB; P45773; -.
DR   SMR; P45773; -.
DR   STRING; 243277.VC_2730; -.
DR   DNASU; 2614893; -.
DR   EnsemblBacteria; AAF95870; AAF95870; VC_2730.
DR   GeneID; 88785285; -.
DR   KEGG; vch:VC_2730; -.
DR   PATRIC; fig|243277.26.peg.2605; -.
DR   eggNOG; COG2165; Bacteria.
DR   HOGENOM; CLU_091705_2_1_6; -.
DR   EvolutionaryTrace; P45773; -.
DR   Proteomes; UP000000584; Chromosome I.
DR   GO; GO:0005886; C:plasma membrane; ISS:UniProtKB.
DR   GO; GO:0015627; C:type II protein secretion system complex; IBA:GO_Central.
DR   GO; GO:0015628; P:protein secretion by the type II secretion system; IBA:GO_Central.
DR   FunFam; 3.30.700.10:FF:000001; General secretion pathway protein G; 1.
DR   Gene3D; 3.30.700.10; Glycoprotein, Type 4 Pilin; 1.
DR   InterPro; IPR000983; GSPG_pilin.
DR   InterPro; IPR012902; N_methyl_site.
DR   InterPro; IPR045584; Pilin-like.
DR   InterPro; IPR013545; T2SS_protein-GspG_C.
DR   InterPro; IPR010054; Type2_sec_GspG.
DR   NCBIfam; TIGR02532; IV_pilin_GFxxxE; 1.
DR   NCBIfam; TIGR01710; typeII_sec_gspG; 1.
DR   PANTHER; PTHR30093; GENERAL SECRETION PATHWAY PROTEIN G; 1.
DR   PANTHER; PTHR30093:SF44; TYPE II SECRETION SYSTEM CORE PROTEIN G; 1.
DR   Pfam; PF07963; N_methyl; 1.
DR   Pfam; PF08334; T2SSG; 1.
DR   PRINTS; PR00813; BCTERIALGSPG.
DR   SUPFAM; SSF54523; Pili subunits; 1.
DR   PROSITE; PS00409; PROKAR_NTER_METHYL; 1.
DR   PDBsum; 3FU1; -.
DR   PDBsum; 4LW9; -.
PE   1: Evidence at protein level;
KW   3D-structure; Cell inner membrane; Cell membrane; Membrane; Methylation;
KW   Protein transport; Reference proteome; Transmembrane; Transmembrane helix;
KW   Transport.
FT   PROPEP          1..9
FT                   /note="Leader sequence"
FT                   /evidence="ECO:0000250|UniProtKB:Q00514"
FT                   /id="PRO_0000449509"
FT   CHAIN           10..146
FT                   /note="Type II secretion system core protein G"
FT                   /id="PRO_0000024211"
FT   TRANSMEM        10..30
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   MOD_RES         10
FT                   /note="N-methylphenylalanine"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01070"
FT   MUTAGEN         100
FT                   /note="D->E: Complete loss of secretion."
FT                   /evidence="ECO:0000269|PubMed:21255118"
FT   MUTAGEN         121
FT                   /note="T->L: Complete loss of secretion."
FT                   /evidence="ECO:0000269|PubMed:21255118"
FT   HELIX           36..63
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   HELIX           66..68
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   TURN            69..71
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   HELIX           73..76
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   STRAND          93..96
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   STRAND          107..111
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   STRAND          113..121
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   TURN            123..126
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   STRAND          127..129
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   HELIX           132..134
FT                   /evidence="ECO:0007829|PDB:3FU1"
FT   HELIX           139..145
FT                   /evidence="ECO:0007829|PDB:3FU1"
SQ   SEQUENCE   146 AA;  16080 MW;  2B211AA994761E2A CRC64;
     MKKMRKQTGF TLLEVMVVVV ILGILASFVV PNLLGNKEKA DQQKAVTDIV ALENALDMYK
     LDNSVYPTTD QGLEALVTKP TNPEPRNYRE GGYIKRLPKD PWGNDYQYLS PGDKGTIDVF
     TLGADGQEGG EGTGADIGNW NIQDFQ
//