XI International Meeting on Paracoccidioidomycosis

XI International Meeting on Paracoccidioidomycosis

Resume:14-1

Poster (Painel)

14-1	Partial biological characterization of a recombinant protein from Paracoccidioides brasiliensis.
Authors:	Ana Claudia Paiva Alegre (FMRP-USP - Faculdade de Medicina de Ribeirão Preto) ; Fausto Bruno dos Reis Almeida (FMRP-USP - Faculdade de Medicina de Ribeirão Preto) ; Ebert Seixas Hanna (INVENT BIOTECNOLOGIA - Invent Biotecnologia Ltda ME) ; Maria Cristina Roque Barreira (FMRP-USP - Faculdade de Medicina de Ribeirão Preto)

Abstract

The most prevalent deep mycosis in South America is caused by Paracoccidioides brasiliensis . When fractionated through affinity to immobilized N -acetilglucosamina (GlcNAc), the soluble extract from Paracoccidioides brasiliensis is enriched to few components, which is denominate as paracoccin preparation (PCN – prep). This preparation has some constituent (s) that promotes fungal adherence to extracellular matrix (ECM) and induces macrophages to produce high concentrations of TNF - alpha and nitric oxide (NO). Both activities were shown to be inhibited in the presence of soluble N -acetilglucosamina (GlcNAc). In addition, paracoccin preparation (PCN - prep) was shown to be endowed of chitinase activity. This preparation was submitted to proteomic analysis and we could identify a gene encoding for a multidomain protein, containing both chitin-binding and chitinase domains, denoted by a Paracoccidioides brasiliensis genebank as PADG _03347. This gene cloned into vectors for expression in Escherichia coli BL21 (DE3). The recombinant protein was purified by affinity to N -acetylglucosamine (GlcNAc) and characterized for its N -acetyl-β-D-glucosaminidase activity. In addition, the recombinant protein was able to bind laminin and to induce the production of TNF - alpha and nitric oxide (NO) by murine macrophages; both properties were inhibited in the presence of soluble N -acetilglucosamina (GlcNAc). Thus, paracoccin preparation (PCN - prep) biological properties were reproduced by the protein encoded by the PADG _03347 gene. The relevance of these biological properties for the fungal biology, and for its relationship with host cells, has motivated the investment of further efforts to fully characterize this protein. ਀ This work was supported by Fapesp and Faepa.਀

Keyword: chitinase, chitin-binding, PADG_03347, Paracoccidioides brasiliensis

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