MHJ_0461 is a multifunctional leucine aminopeptidase on the surface of Mycoplasma hyopneumoniae

Veronica M Jarocki; Jerran Santos; Jessica L Tacchi; Benjamin B A Raymond; Ania T Deutscher; Cheryl Jenkins; Matthew P Padula; Steven P Djordjevic

doi:10.1098/rsob.140175

MHJ_0461 is a multifunctional leucine aminopeptidase on the surface of Mycoplasma hyopneumoniae

Open Biol. 2015 Jan;5(1):140175. doi: 10.1098/rsob.140175.

Authors

Veronica M Jarocki¹, Jerran Santos², Jessica L Tacchi¹, Benjamin B A Raymond¹, Ania T Deutscher³, Cheryl Jenkins³, Matthew P Padula², Steven P Djordjevic⁴

Affiliations

¹ The ithree institute, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007, Australia.
² 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.
³ NSW Department of Primary Industries, Private Bag 4008, Narellan, New South Wales 2567, Australia.
⁴ 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.

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.

Keywords: DNA-binding protein; adhesin; heparin-binding protein; leucine aminopeptidase; moonlighting protein; plasminogen-binding protein.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acid Sequence
Amino Acids / metabolism
Bacterial Proteins / chemistry
Bacterial Proteins / genetics
Bacterial Proteins / metabolism*
Binding Sites
Heparin / metabolism
Leucyl Aminopeptidase / chemistry
Leucyl Aminopeptidase / genetics
Leucyl Aminopeptidase / metabolism*
Membrane Proteins / chemistry
Membrane Proteins / genetics
Membrane Proteins / metabolism*
Molecular Sequence Data
Mycoplasma hyopneumoniae / enzymology*
Plasminogen / metabolism
Protein Binding
Substrate Specificity

Substances

Amino Acids
Bacterial Proteins
Membrane Proteins
Plasminogen
Heparin
Leucyl Aminopeptidase