title: Proteome profiling of the dimorphic fungus Penicillium marneffei extracellular proteins and identification of glyceraldehyde-3-phosphate dehydrogenase as an important adhesion factor for conidial attachment.
abstract: Despite being the most important thermal dimorphic fungus causing systemic mycosis in Southeast Asia, the pathogenic mechanisms of Penicillium marneffei remain largely unknown. By comparing the extracellular proteomes of P. marneffei in mycelial and yeast phases, we identified 12 differentially expressed proteins among which glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and heat shock protein 60 (HSP60) were found to be upregulated in mycelial and yeast phases respectively. Based on previous findings in other pathogens, we hypothesized that these two extracellular proteins may be involved in adherence during P. marneffei-host interaction. Using inhibition assays with recombinant GAPDH (rGAPDH) proteins and anti-rGAPDH sera, we demonstrated that adhesion of P. marneffei conidia to fibronectin and laminin was inhibited by rGAPDH or rabbit anti-rGAPDH serum in a dose-dependent manner. Similarly, a dose-dependent inhibition of conidial adherence to A549 pneumocytes by rGAPDH or rabbit anti-rGAPDH serum was observed, suggesting that P. marneffei GAPDH can mediate binding of conidia to human extracellular matrix proteins and pneumocytes. However, HSP60 did not exhibit similar inhibition on conidia adherence, and neither GAPDH norHSP60 exhibited inhibition on adherence to J774 or THP-1 macrophage cell lines. This report demonstrates GAPDH as an adherence factor in P. marneffei by mediating conidia adherence to host bronchoalveolar epithelium during the early establishment phase of infection.
authors.affiliation: State Key Laboratory of Emerging Infectious Diseases, Research Centre of Infection and Immunology and Carol Yu Centre for Infection, University of Hong Kong, China; Department of Microbiology, University of Hong Kong, China.
authors.forename: Susanna K P
authors.initials: SK
authors.lastname: Lau
authors.forename: Herman
authors.initials: H
authors.lastname: Tse
authors.forename: Joanna S Y
authors.initials: JS
authors.lastname: Chan
authors.forename: Anna C
authors.initials: AC
authors.lastname: Zhou
authors.forename: Shirly O T
authors.initials: SO
authors.lastname: Curreem
authors.forename: Candy C Y
authors.initials: CC
authors.lastname: Lau
authors.forename: Kwok-Yung
authors.initials: KY
authors.lastname: Yuen
authors.forename: Patrick C Y
authors.initials: PC
authors.lastname: Woo
mesh_terms: D056809:Alveolar Epithelial Cells / Q000166:cytology / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D002448:Cell Adhesion / Q000502:physiology*; D002478:Cells, Cultured; D018834:Chaperonin 60 / Q000235:genetics / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D005656:Fungal Proteins / Q000378:metabolism*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007797:Laminin / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D025282:Mycelium / Q000166:cytology / Q000378:metabolism; D009181:Mycoses / Q000378:metabolism / Q000382:microbiology; D010407:Penicillium / Q000254:growth & development / Q000378:metabolism*; D020543:Proteome / Q000032:analysis*; D012333:RNA, Messenger / Q000235:genetics; D011817:Rabbits; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013172:Spores, Fungal / Q000378:metabolism*; D015003:Yeasts / Q000254:growth & development / Q000378:metabolism
chemical_list: D018834:Chaperonin 60; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D005656:Fungal Proteins; D007797:Laminin; D020543:Proteome; D012333:RNA, Messenger; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases
keywords: Penicillium marneffei; Proteome; adhesion factor; extracellular; glyceraldehyde-3-phosphate dehydrogenase