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23 Congress of the International Union for Biochemistry and Molecular Biology
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44 Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology
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Foz do Iguaçu, PR, Brazil, August 24 to 28 , 2015
CELL WALL COMPOSITION OF FUSARIUM SOLANI AND
NEOCOSMOSPORA VASINFECTA UNDER THE INFLUENCE OF DIFERENTS
CARBON SOURCES
Galvão, D.F.A.1,2; Elsztein, C. 3; Pessoni, R.A. B. 4; Simões, K. 5; Gaspar, M. 5;
Morais, M.A.M. Jr. 3; Morais, M.M.C. 6; Braga, M. R. 5
1
Unidade Acadêmica de Garanhuns, Universidade Federal Rural de Pernambuco,
Garanhuns, PE, Brazil;2Programa de Pós-Graduação em Biologia Celular e
Estrutural, Universidade Estadual de Campinas, Campinas, SP, Brazil, 3
Departamento de Genética, Universidade Federal de Pernambuco, Recife, PE,
Brazil, 4Universidade Metodista de São Paulo, Faculdade da Saúde, São Bernardo
do Campo, SP, Brazil, 5Núcleo de Pesquisa em Fisiologia e Bioquímica, Instituto
de Botânica, São Paulo, SP, Brazil, 6 Instituto de Ciências Biológicas,
Universidade de Pernambuco, Recife, PE, Brazil.
The cell wall of fungi is an interactive structure whose composition varies with
environmental changes. We analysed the influence of different carbon sources on
cell wall composition of Neocosmospora vasinfecta and Fusarium solani, two fungi
isolated from the rhizosphere of Chrysolaena obovata and capable of metabolizing
fructans. Fungi were grown in five carbon sources (inulin, sucrose, glucose,
fructose, glucose plus fructose) and the content of total sugars and chitin were
measured in the cell walls. Sugar composition was analysed by HPAEC/PAD.
Expression of the genes involved in cell wall synthesis was evaluated by RTqPCR. Cell wall composition was influenced by carbon source and culture age.
High proportion of neutral sugars was observed in F. solani, mainly represented by
glucose, mannose and galactose for all carbon sources. Contents of glucose
decreased and arabinose increased with culture age. Moreover, chitin content
doubled during the cultivation in all media. In agreement with these data, genes
coding for beta-1,3 glucan synthase, chitin synthase 2 and chitin synthase 7 were
induced upon cultivation in sucrose or inulin. In N. vasinfecta, glucose, mannose
and galactose were predominant in the cell walls independently of the carbon
source. The content of arabinose decreased mainly in the inulin- and fructosecontaining media, while an increase in glucose content was observed. No changes
in the content of chitin were observed during cultivation. Cultivation in inulin
resulted in the highest induction of beta-1,3 glucan synthase, CHS2, CHS5 e
CHS4 genes. In conclusion, inulin stimulates growth of both fungi however distinct
carbon sources differently changed their cell wall composition. Considering that
cell wall is the main target for antifungal substances, the fungal sensibility to
fungicides may vary depending on the carbon sources in which fungi are cultivated
(FAPESP 2012/16332-0, CNPq, CAPES).
Key Words: fungi, carbon source, cell wall
Brazilian Society for Biochemistry and
Molecular Biology (SBBq)