title: Streptococcus pneumoniae Cell-Wall-Localized Phosphoenolpyruvate Protein Phosphotransferase Can Function as an Adhesin: Identification of Its Host Target Molecules and Evaluation of Its Potential as a Vaccine.
abstract: In Streptococcus pneumonia, phosphoenolpyruvate protein phosphotransferase (PtsA) is an intracellular protein of the monosaccharide phosphotransferase systems. Biochemical and immunostaining methods were applied to show that PtsA also localizes to the bacterial cell-wall. Thus, it was suspected that PtsA has functions other than its main cytoplasmic enzymatic role. Indeed, recombinant PtsA and anti-rPtsA antiserum were shown to inhibit adhesion of S. pneumoniae to cultured human lung adenocarcinoma A549 cells. Screening of a combinatorial peptide library expressed in a filamentous phage with rPtsA identified epitopes that were capable of inhibiting S. pneumoniae adhesion to A549 cells. The insert peptides in the phages were sequenced, and homologous sequences were found in human BMPER, multimerin1, protocadherin19, integrinβ4, epsin1 and collagen type VIIα1 proteins, all of which can be found in A549 cells except the latter. Six peptides, synthesized according to the homologous sequences in the human proteins, specifically bound rPtsA in the micromolar range and significantly inhibited pneumococcal adhesion in vitro to lung- and tracheal-derived cell lines. In addition, the tested peptides inhibited lung colonization after intranasal inoculation of mice with S. pneumoniae. Immunization with rPtsA protected the mice against a sublethal intranasal and a lethal intravenous pneumococcal challenge. In addition, mouse anti rPtsA antiserum reduced bacterial virulence in the intravenous inoculation mouse model. These findings showed that the surface-localized PtsA functions as an adhesin, PtsA binding peptides derived from its putative target molecules can be considered for future development of therapeutics, and rPtsA should be regarded as a candidate for vaccine development.
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Yaffa
authors.initials: Y
authors.lastname: Mizrachi Nebenzahl
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Karin
authors.initials: K
authors.lastname: Blau
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Tatyana
authors.initials: T
authors.lastname: Kushnir
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Marilou
authors.initials: M
authors.lastname: Shagan
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Maxim
authors.initials: M
authors.lastname: Portnoi
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Aviad
authors.initials: A
authors.lastname: Cohen
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Shalhevet
authors.initials: S
authors.lastname: Azriel
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Itai
authors.initials: I
authors.lastname: Malka
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Asad
authors.initials: A
authors.lastname: Adawi
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kafka
authors.affiliation: NasVax Ltd, Ness Ziona, Israel.
authors.forename: Shahar
authors.initials: S
authors.lastname: Dotan
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Gali
authors.initials: G
authors.lastname: Guterman
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Shany
authors.initials: S
authors.lastname: Troib
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Tali
authors.initials: T
authors.lastname: Fishilevich
authors.affiliation: Department of Cell Research and Immunology, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Gershoni
authors.affiliation: The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Alex
authors.initials: A
authors.lastname: Braiman
authors.affiliation: Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Mitchell
authors.affiliation: Department of Cell Research and Immunology, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Mitchell
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel.|The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.|The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Nurith
authors.initials: N
authors.lastname: Porat
authors.affiliation: National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel.|Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Inna
authors.initials: I
authors.lastname: Goliand
authors.affiliation: National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel.
authors.forename: Vered
authors.initials: V
authors.lastname: Chalifa Caspi
authors.affiliation: Division of Infectious Diseases, University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Edwin
authors.initials: E
authors.lastname: Swiatlo
authors.affiliation: NasVax Ltd, Ness Ziona, Israel.
authors.forename: Michael
authors.initials: M
authors.lastname: Tal
authors.affiliation: NasVax Ltd, Ness Ziona, Israel.
authors.forename: Ronald
authors.initials: R
authors.lastname: Ellis
authors.affiliation: National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer Sheva, Israel.|Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Natalie
authors.initials: N
authors.lastname: Elia
authors.affiliation: The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Ron
authors.initials: R
authors.lastname: Dagan
mesh_terms: D018829:Adhesins, Bacterial / Q000502:physiology; D045744:Cell Line, Tumor; D002473:Cell Wall / Q000201:enzymology*; D002675:Child, Preschool; D005434:Flow Cytometry; D006801:Humans; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000378:metabolism*; D017852:Phosphotransferases (Nitrogenous Group Acceptor) / Q000378:metabolism*; D022242:Pneumococcal Vaccines / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000201:enzymology* / Q000276:immunology
chemical_list: D018829:Adhesins, Bacterial; D022242:Pneumococcal Vaccines; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; D017852:Phosphotransferases (Nitrogenous Group Acceptor); C022360:phosphoenolpyruvate-protein phosphotransferase