title: Characterization of a unique ADP-ribosyltransferase of Mycoplasma penetrans.
abstract: Mycoplasma penetrans is a urogenital tract pathogen implicated in the deterioration of the immune system in human immunodeficiency virus-infected AIDS patients. Here, we describe a 78-kDa protein from M. penetrans, designated MYPE9110, that exhibits sequence similarity to known ADP-ribosyltransferases (ADPRTs) such as Bordetella pertussis pertussis toxin and Mycoplasma pneumoniae community-acquired respiratory distress syndrome toxin. MYPE9110 possesses key amino acid residues found in all ADPRTs that are essential for ADPRT activity. Several mammalian cell proteins are ADP-ribosylated by MYPE9110, and the full-length recombinant protein exhibits a strong auto-ADP-ribosylating activity. In the absence of target proteins, MYPE9110 demonstrates a NAD-glycohydrolase activity by hydrolyzing NAD. Furthermore, this toxin elicits cytopathology in HeLa cells by inducing cytoplasmic vacuolization in the presence of ammonium chloride. The deletion of the C-terminal region of MYPE9110 significantly diminishes its binding to host cells while still exhibiting an ADPRT activity, suggesting that MYPE9110 is a member of the family of A-B ADPRT toxins.
authors: Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, MC 7758, San Antonio, TX 78229-3900, USA.
authors: Coreen
authors: C
authors: Johnson
authors: T R
authors: TR
authors: Kannan
authors: Joel B
authors: JB
authors: Baseman
mesh_terms: D036002:ADP Ribose Transferases / Q000235:genetics* / Q000378:metabolism*; D001427:Bacterial Toxins / Q000235:genetics* / Q000378:metabolism*; D001886:Bordetella pertussis / Q000235:genetics; D023061:Gene Order; D005798:Genes, Bacterial; D006367:HeLa Cells; D006801:Humans; D018661:Mycoplasma penetrans / Q000201:enzymology*; D009177:Mycoplasma pneumoniae / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D001427:Bacterial Toxins; D036002:ADP Ribose Transferases