title: Transcriptome analysis reveals pathogenicity and evolutionary history of the pathogenic oomycete Pythium insidiosum.
abstract: Oomycetes form a unique group of microorganisms that share hyphal morphology with fungi. Most of pathogenic oomycetes infect plants, while some species are capable of infecting animals. Pythium insidiosum is the only oomycete that can infect both humans and animals, and causes a life-threatening infectious disease, called 'pythiosis'. Controlling an infection caused by P. insidiosum is problematic because effective antimicrobial drugs are not available. Information on the biology and pathogenesis of P. insidiosum is limited. We generated a P. insidiosum transcriptome of 26 735 unigenes, using the 454 sequencing platform. As adaptations to increased temperature inside human hosts are required for a successful pathogen, we generated P. insidiosum transcriptomes at 28 °C and 37 °C and identified 625 up-regulated and 449 down-regulated genes at 37 °C. Comparing the proteomes of oomycetes, fungi, and parasites provided clues on the evolutionary history of P. insidiosum. Potential virulence factors of P. insidiosum, including putative effectors, were identified. Pythium insidiosum harbored an extensive repertoire of ∼ 300 elicitin domain-containing proteins. The transcriptome, presented herein, provides an invaluable resource for exploring P. insidiosum's biology, pathogenesis, and evolution.
authors.affiliation: Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok. Electronic address: mr_en@hotmail.com.
authors.forename: Theerapong
authors.initials: T
authors.lastname: Krajaejun
authors.affiliation: Molecular Medicine Program, Multidisciplinary Unit, Faculty of Science, Mahidol University, Bangkok.
authors.forename: Tassanee
authors.initials: T
authors.lastname: Lerksuthirat
authors.affiliation: Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, New South Wales, Australia.
authors.forename: Gagan
authors.initials: G
authors.lastname: Garg
authors.affiliation: Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok.
authors.forename: Tassanee
authors.initials: T
authors.lastname: Lowhnoo
authors.affiliation: Research Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok.
authors.forename: Wanta
authors.initials: W
authors.lastname: Yingyong
authors.affiliation: Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok.
authors.forename: Rommanee
authors.initials: R
authors.lastname: Khositnithikul
authors.affiliation: National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani, Thailand.
authors.forename: Sithichoke
authors.initials: S
authors.lastname: Tangphatsornruang
authors.affiliation: Bioinformatics and Data Management for Research, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok.
authors.forename: Prapat
authors.initials: P
authors.lastname: Suriyaphol
authors.affiliation: Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, New South Wales, Australia; Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
authors.forename: Shoba
authors.initials: S
authors.lastname: Ranganathan
authors.affiliation: Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA.
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Sullivan
mesh_terms: D005075:Biological Evolution; D020869:Gene Expression Profiling; D008969:Molecular Sequence Data; D020543:Proteome / Q000032:analysis; D011775:Pythium / Q000235:genetics* / Q000276:immunology*; D017422:Sequence Analysis, DNA; D013696:Temperature; D037521:Virulence Factors / Q000032:analysis
chemical_list: D020543:Proteome; D037521:Virulence Factors
keywords: Effector; Expressed sequence tag; Human pathogen; Pythiosis; Virulence factor