Protein
Serine/threonine-protein kinase CtkA
Organism
Helicobacter pylori (strain J99 / ATCC 700824)
Function
Virulence factor acting as a proinflammatory protein that induces the secretion of the proinflammatory cytokines TNF-alpha (tumor necrosis factor-alpha) and IL-8 (interleukin-8) from human macrophages, as well as enhanced translocation of the transcription factor NF-kappa-B complex in macrophages. Is a kinase capable of autophosphorylating itself at a threonine residue near the N-terminus. Also leads to enhanced phosphorylation of the NF-kappa-B p65 subunit (RELA) at 'Ser-276' in human epithelial cancer cells; its kinase activity is required for this enhanced phosphorylation that up-regulates NF-kappa-B activity, but it does not directly phosphorylate this protein. Thus, the kinase activity of CtkA may play an important role in the induction of host inflammatory responses during H.pylori infection.
Sequence
MPTIDFTFCEINPKKGFGGANGNKISLFYNNELYMVKFPPKPSTHKEMSYTNGCFSEYVACHIVNSLGLKVQETLLGTYKNKIVVACKDFTTHQYELVDFLSLKNTMIELEKSGKDTNLNDVLYAIDNQHFIEPKVLKCFFWDMFVADTLLGNFDRHNGNWGFLRASNSKEYQIAPIFDCGSCLYPQADDVVCQKVLSNIDELNARIYNFPQSILKDDNDKKINYYDFLTQTNNKDCLDALLRIYPRIDMNKIHSIIDNTPFMSEIHKEFLHTMLDERKSKIIDVAHTRAIELSLQHKQAHSNPYDNADDLDNSNEYTPTPKRRR