title: MHJ_0461 is a multifunctional leucine aminopeptidase on the surface of Mycoplasma hyopneumoniae.
abstract: Aminopeptidases are part of the arsenal of virulence factors produced by bacterial pathogens that inactivate host immune peptides. Mycoplasma hyopneumoniae is a genome-reduced pathogen of swine that lacks the genetic repertoire to synthesize amino acids and relies on the host for availability of amino acids for growth. M. hyopneumoniae recruits plasmin(ogen) onto its cell surface via the P97 and P102 adhesins and the glutamyl aminopeptidase MHJ_0125. Plasmin plays an important role in regulating the inflammatory response in the lungs of pigs infected with M. hyopneumoniae. We show that recombinant MHJ_0461 (rMHJ_0461) functions as a leucine aminopeptidase (LAP) with broad substrate specificity for leucine, alanine, phenylalanine, methionine and arginine and that MHJ_0461 resides on the surface of M. hyopneumoniae. rMHJ_0461 also binds heparin, plasminogen and foreign DNA. Plasminogen bound to rMHJ_0461 was readily converted to plasmin in the presence of tPA. Computational modelling identified putative DNA and heparin-binding motifs on solvent-exposed sites around a large pore on the LAP hexamer. We conclude that MHJ_0461 is a LAP that moonlights as a multifunctional adhesin on the cell surface of M. hyopneumoniae.
authors.affiliation: The ithree institute, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia.
authors.forename: Veronica M
authors.initials: VM
authors.lastname: Jarocki
authors.affiliation: The ithree institute, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia Proteomics Core Facility, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia.
authors.forename: Jerran
authors.initials: J
authors.lastname: Santos
authors.affiliation: The ithree institute, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia.
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Tacchi
authors.affiliation: The ithree institute, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia.
authors.forename: Benjamin B A
authors.initials: BB
authors.lastname: Raymond
authors.affiliation: NSW Department of Primary Industries, Private Bag 4008, Narellan, New South Wales 2567, Australia.
authors.forename: Ania T
authors.initials: AT
authors.lastname: Deutscher
authors.affiliation: NSW Department of Primary Industries, Private Bag 4008, Narellan, New South Wales 2567, Australia.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Jenkins
authors.affiliation: The ithree institute, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia Proteomics Core Facility, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Padula
authors.affiliation: The ithree institute, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia Proteomics Core Facility, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia steven.djordjevic@uts.edu.au.
authors.forename: Steven P
authors.initials: SP
authors.lastname: Djordjevic
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D006493:Heparin / Q000378:metabolism; D007931:Leucyl Aminopeptidase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D045705:Mycoplasma hyopneumoniae / Q000201:enzymology*; D010958:Plasminogen / Q000378:metabolism; D011485:Protein Binding; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D008565:Membrane Proteins; D010958:Plasminogen; D006493:Heparin; D007931:Leucyl Aminopeptidase
keywords: DNA-binding protein; adhesin; heparin-binding protein; leucine aminopeptidase; moonlighting protein; plasminogen-binding protein