Characterization of Lipids and Proteins Associated to the Cell Wall of the Acapsular Mutant Cryptococcus neoformans Cap 67

Autor(es)

Longo, Larissa V. G. ^[1] ; Nakayasu, Ernesto S. ^[2] ; Pires, Jhon H. S. ^[1] ; Gazos-Lopes, Felipe ^[2] ; Vallejo, Milene C. ^[1] ; Sobreira, Tiago J. P. ^[3] ; Almeida, Igor C. ^[2] ; Puccia, Rosana ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, EPM UNIFESP, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 Sao Paulo, SP - Brazil

^[2] Univ Texas El Paso, Dept Biol Sci, Border Biomed Res Ctr, El Paso, TX 79968 - USA

^[3] Ctr Nacl Pesquisa Energia & Mat, Lab Nacl Biociencias LNBio, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Eukaryotic Microbiology; v. 62, n. 5, p. 591-604, SEP-OCT 2015.
• Citações Web of Science: 2

Resumo

Cryptococcus neoformans is an opportunistic human pathogen that causes life-threatening meningitis. In this fungus, the cell wall is exceptionally not the outermost structure due to the presence of a surrounding polysaccharide capsule, which has been highly studied. Considering that there is little information about C. neoformans cell wall composition, we aimed at describing proteins and lipids extractable from this organelle, using as model the acapsular mutant C. neoformans cap 67. Purified cell wall preparations were extracted with either chloroform/methanol or hot sodium dodecyl sulfate. Total lipids fractionated in silica gel 60 were analyzed by electrospray ionization tandem mass spectrometry (ESI-MS/MS), while trypsin digested proteins were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). We detected 25 phospholipid species among phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and phosphatidic acid. Two glycolipid species were identified as monohexosyl ceramides. We identified 192 noncovalently linked proteins belonging to different metabolic processes. Most proteins were classified as secretory, mainly via nonclassical mechanisms, suggesting a role for extracellular vesicles (EV) in transwall transportation. In concert with that, orthologs from 86% of these proteins have previously been reported both in fungal cell wall and/or in EV. The possible role of the presently described structures in fungal-host relationship is discussed. (AU)

• Processo FAPESP: 13/25950-1 - Expressão e regulação de genes relacionados à parede celular de fungos dimórficos patogênicos sob condições de estresse
• Beneficiário: Rosana Puccia
• Modalidade de apoio: Auxílio à Pesquisa - Regular