Protein: Outer membrane autotransporter IcsA (Outer membrane autotransporter VirG) [Cleaved into: IcsA alpha domain (IcsA passenger domain) (VirG alpha domain); Outer membrane protein IcsA translocator domain (Outer membrane protein IcsA beta domain)] (Q7BCK4)
Organism: Shigella flexneri
Function: An immunogenic protein essential for bacterial spreading, it elicits polar deposition of filamentous actin (actin-based motility). Inside the host (human) cell mediates nucleation and polymerization of actin molecules on the bacterial surface, which provides the propulsive force for intracellular movement and intercellular dissemination of the bacterium. During invasion of mammalian cells, triggers autophagy by binding to host ATG5. Interaction with IcsB leads to escape from the host autophagy defense system. Binds ATP and displays weak ATPase activity. Mediates polar adhesion to host cells and their invasion. The bile salt deoxycholate activates adhesion and invasion of host cells, possibly by altering IcsA's conformation. The adhesion and intercellular dissemination phenotypes can be separated.
Subcellular location: [Outer membrane autotransporter IcsA]: Periplasm. Cell outer membrane {ECO:0000269|PubMed:10231492, ECO:0000269|PubMed:2542950}. Cell surface {ECO:0000269|PubMed:8702989}. Note=This protein can be detected in infected (human) MK2 cells. {ECO:0000269|PubMed:7896693}.; SUBCELLULAR LOCATION: [IcsA alpha domain]: Secreted {ECO:0000269|PubMed:14507362, ECO:0000269|PubMed:7896693, ECO:0000269|PubMed:8468279}. Cell surface {ECO:0000269|PubMed:14507362, ECO:0000269|PubMed:16788193, ECO:0000269|PubMed:2644195, ECO:0000269|PubMed:8702989}. Note=The alpha domain is localized as a cap over the old pole of the bacterial surface (PubMed:10231492, PubMed:11481451, PubMed:14507362, PubMed:16788193, PubMed:8468279). Cleavage of this fragment requires genes controlled by virB. This protein fragment can be detected in infected (human) MK2 cells (PubMed:7896693). Colocalizes with SepA at the old cell pole (PubMed:16788193). {ECO:0000269|PubMed:10231492, ECO:0000269|PubMed:11481451, ECO:0000269|PubMed:14507362, ECO:0000269|PubMed:16788193, ECO:0000269|PubMed:7896693, ECO:0000269|PubMed:8468279}.; SUBCELLULAR LOCATION: [Outer membrane protein IcsA translocator domain]: Cell outer membrane {ECO:0000269|PubMed:7896693, ECO:0000269|PubMed:8537341}; Multi-pass membrane protein {ECO:0000305|PubMed:8537341}. Note=The cleaved C-terminal fragment (autotransporter domain) is localized in the outer membrane. This protein fragment can be detected in infected (human) MK2 cells. {ECO:0000269|PubMed:7896693}.
Interaction partners:
Sequence:
MNQIHKFFCNMTQCSQGGAGELPTVKEKTCKLSFSPFVVGASLLLGGPIAFATPLSGTQELHFSEDNYEKLLTPVDGLSPLGAGEDGMDAWYITSSNPSHASRTKLRINSDIMISAGHGGAGDNNDGNSCGGNGGDSITGSDLSIINQGMILGGSGGSGADHNGDGGEAVTGDNLFIINGEIISGGHGGDSYSDSDGGNGGDAVTGVNLPIINKGTISGGNGGNNYGEGDGGNGGDAITGSSLSVINKGTFAGGNGGAAYGYGYDGYGGNAITGDNLSVINNGAILGGNGGHWGDAINGSNMTIANSGYIISGKEDDGTQNVAGNAIHITGGNNSLILHEGSVITGDVQVNNSSILKIINNDYTGTTPTIEGDLCAGDCTTVSLSGNKFTVSGDVSFGENSSLNLAGISSLEASGNMSFGNNVKVEAIINNWAQKDYKLLSADKGITGFSVSNISIINPLLTTGAIDYTKSYISDQNKLIYGLSWNDTDGDSHGEFNLKENAELTVSTILADNLSHHNINSWDGKSLTKSGEGTLILAEKNTYSGFTNINAGILKMGTVEAMTRTAGVIVNKGATLNFSGMNQTVNTLLNSGTVLINNINAPFLPDPVIVTGNMTLEKNGHVILNNSSSNVGQTYVQKGNWHGKGGILSLGAVLGNDNSKTDRLEIAGHASGITYVAVTNEGGSGDKTLEGVQIISTDSSDKNAFIQKGRIVAGSYDYRLKQGTVSGLNTNKWYLTSQMDNQESKQMSNQESTQMSSRRASSQLVSSLNLGEGSIHTWRPEAGSYIANLIAMNTMFSPSLYDRHGSTIVDPTTGQLSETTMWIRTVGGHNEHNLADRQLKTTANRMVYQIGGDILKTNFTDHDGLHVGIMGAYGYQDSKTHNKYTSYSSRGTVSGYTAGLYSSWFQDEKERTGLYMDAWLQYSWFNNTVKGDGLTGEKYSSKGITGALEAGYIYPTIRWTAHNNIDNALYLNPQVQITRHGVKANDYIEHNGTMVTSSGGNNIQAKLGLRTSLISQSCIDKETLRKFEPFLEVNWKWSSKQYGVIMNGMSNHQIGNRNVIELKTGVGGRLADNLSIWGNVSQQLGNNSYRDTQGILGVKYTF