title: Characterization of recombinant Streptococcus mitis-derived human platelet aggregation factor.
abstract: We previously purified Streptococcus mitis-derived human platelet aggregation factor (Sm-hPAF) from the culture supernatant of S. mitis strain Nm-65, isolated from the tooth surface of a patient with Kawasaki disease. Here we produced recombinant Sm-hPAF protein (rSm-hPAF) in Escherichia coli, to determine whether rSm-hPAF conserves its platelet aggregation activity. rSm-hPAF precursor (665 amino acids) shows up to 36-56% identity with the family of cholesterol-dependent cytolysins (CDCs), and rSm-hPAF displayed potent hemolytic activity toward mammalian erythrocytes, including human erythrocytes with platelet aggregation activity. The 162-amino acid amino-terminal domain of rSm-hPAF was found in no other CDCs except lectinolysin; this domain is homologous to a portion of pneumococcal fucolectin-related protein. Interestingly, suilysin (SLY) and pneumolysin (PLY) of CDCs also exhibit substantial human platelet aggregation activity, similar to rSm-hPAF, and the platelet aggregation by rSm-hPAF, SLY, and PLY was morphologically confirmed using light and electron microscopy.
authors.affiliation: Health Science Research Institute East Japan Co. Ltd, Kounosu, Saitama, Japan. h-okuni@nms.ac.jp
authors.forename: Hisashi
authors.initials: H
authors.lastname: Ohkuni
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nagamune
authors.forename: Nana
authors.initials: N
authors.lastname: Ozaki
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tabata
authors.forename: Yuko
authors.initials: Y
authors.lastname: Todome
authors.forename: Yukino
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Hidemi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Kazuto
authors.initials: K
authors.lastname: Ohkura
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kourai
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ohtsuka
authors.forename: Vincent A
authors.initials: VA
authors.lastname: Fischetti
authors.forename: John B
authors.initials: JB
authors.lastname: Zabriskie
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001426:Bacterial Proteins / Q000633:toxicity; D001427:Bacterial Toxins / Q000737:chemistry* / Q000235:genetics / Q000633:toxicity*; D001483:Base Sequence; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D015815:Cell Adhesion Molecules / Q000737:chemistry* / Q000235:genetics / Q000633:toxicity*; D002784:Cholesterol / Q000737:chemistry; D003603:Cytotoxins / Q000737:chemistry* / Q000235:genetics / Q000633:toxicity*; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D005798:Genes, Bacterial; D006460:Hemolysin Proteins / Q000633:toxicity; D006801:Humans; D066298:In Vitro Techniques; D007770:L-Lactate Dehydrogenase / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D009080:Mucocutaneous Lymph Node Syndrome / Q000097:blood / Q000209:etiology / Q000382:microbiology; D010802:Phylogeny; D010974:Platelet Aggregation / Q000187:drug effects*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000633:toxicity; D017386:Sequence Homology, Amino Acid; D034361:Streptococcus mitis / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D013301:Streptolysins / Q000633:toxicity
chemical_list: D000911:Antibodies, Monoclonal; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D015815:Cell Adhesion Molecules; D003603:Cytotoxins; D004269:DNA, Bacterial; D006460:Hemolysin Proteins; D011994:Recombinant Proteins; D013301:Streptolysins; C013065:cell aggregation factors; C032290:plY protein, Streptococcus pneumoniae; C104760:suilysin; D002784:Cholesterol; D007770:L-Lactate Dehydrogenase