caa a22 4500 378849603 CHVBK 20180305123320.0 cr unu---uuuuu 161128e20030127xx s 000 0 eng 10.1515/BC.2003.013 doi (NATIONALLICENCE)gruyter-10.1515/BC.2003.013 The PPIase Active Site of Legionellapneumophila Mip Protein Is Involved in theInfection of Eukaryotic Host Cells [Elektronische Daten] [J.H. Helbig, B. König, H. Knospe, B. Bubert, C. Yu, C.P. Lück, A. Riboldi-Tunnicliffe, R. Hilgenfeld, E. Jacobs, J. Hacker, G. Fischer] We analysed eight monoclonal antibodies (mAbs) directed against the Mip (macrophage infectivity potentiator) protein, a virulence factor of the intracellular pathogen Legionella pneumophila. Mip belongs to the FK506-binding proteins (FKBPs) and exhibits peptidyl prolyl cis/trans isomerase (PPIase) activity. Five of the mAbs recognised epitopes in the Cterminal, FKBP-homologous domain of Mip, which is highly conserved among all Legionella species. Upon immunological binding to Mip, all but one of these mAbs caused inhibition of the PPIase activity in vitro. mAb binding to the N-terminal domain of Mip did not influence its enzymatic activity. All but one of the PPIase inhibiting mAbs were able to significantly inhibit the early establishment and initiation of an intracellular infection of the bacteria in Acanthamoeba castellanii, the natural host, and in the human phagocytic cell line U937. These data demonstrate for the first time that for the virulence-enhancing property of the L. pneumophila Mip protein, an intact active site of the enzyme is an essential requirement. Copyright © 2003 by Walter de Gruyter GmbH & Co. KG Biochemistry nationallicence Molecular biology nationallicence Cellular biology nationallicence Helbig J.H. aut König B. aut Knospe H. aut Bubert B. aut Yu C. aut Lück C.P. aut Riboldi-Tunnicliffe A. aut Hilgenfeld R. aut Jacobs E. aut Hacker J. aut Fischer G. aut Biological Chemistry Walter de Gruyter 384/1(2003-01-27), 125-137 1431-6730 384:1<125 2003 384 bchm https://doi.org/10.1515/BC.2003.013 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1515/BC.2003.013 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Helbig J.H. aut NATIONALLICENCE 700 1- König B. aut NATIONALLICENCE 700 1- Knospe H. aut NATIONALLICENCE 700 1- Bubert B. aut NATIONALLICENCE 700 1- Yu C. aut NATIONALLICENCE 700 1- Lück C.P. aut NATIONALLICENCE 700 1- Riboldi-Tunnicliffe A. aut NATIONALLICENCE 700 1- Hilgenfeld R. aut NATIONALLICENCE 700 1- Jacobs E. aut NATIONALLICENCE 700 1- Hacker J. aut NATIONALLICENCE 700 1- Fischer G. aut NATIONALLICENCE 773 0- Biological Chemistry Walter de Gruyter 384/1(2003-01-27), 125-137 1431-6730 384:1<125 2003 384 bchm CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter