title: N-terminal residues of SipB are required for its surface localization on Salmonella enterica serovar Typhimurium.
abstract: SipB, one of the invasion proteins encoded in Salmonella pathogenicity island 1 (SPI-1), is known to be secreted outside the cell, where it functions as a translocon by assembling into a host-cell plasma membrane-integral structure. Here, we confirmed that wild-type SipB could be localized to the bacterial outer membrane, and further showed that its localization was dependent on extracellular secretion, and was independent of the presence of the SipD protein. Proteinase K susceptibility and immunofluorescence assays indicated that SipB was not incorporated into the outer membrane, but rather was displayed on the bacterial surface. Finally, mutation studies revealed that the N-terminal 100-140 aa (especially amino acids 135-138) of SipB were required for its localization on the bacterial outer membrane.
authors.affiliation: Laboratory of Microbial Genetics, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Hyeon Guk
authors.initials: HG
authors.lastname: Kim
authors.affiliation: Institute of Biotechnology, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.|Laboratory of Microbial Genetics, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Bae Hoon
authors.initials: BH
authors.lastname: Kim
authors.affiliation: Laboratory of Microbial Genetics, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Jin Seok
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Laboratory of Microbial Genetics, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Jeong Seon
authors.initials: JS
authors.lastname: Eom
authors.affiliation: Department of Microbiology and Immunology, Chosun University School of Dentistry, Gwang ju 501-759, Republic of Korea.
authors.forename: Iel-Soo
authors.initials: IS
authors.lastname: Bang
authors.affiliation: Department of Biological Science, Hanseo University, Seosan 356-706, Republic of Korea.
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Bang
authors.affiliation: Department of Microbiology, Hannam University, DaeJeon 300-791, Republic of Korea.
authors.forename: In Soo
authors.initials: IS
authors.lastname: Lee
authors.affiliation: Laboratory of Microbial Genetics, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Yong Keun
authors.initials: YK
authors.lastname: Park
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism; D019286:Endopeptidase K / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D012486:Salmonella typhimurium / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; C094579:invasion protein B, Salmonella typhimurium; D019286:Endopeptidase K