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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Molecular masses and sedimentation coefficients of extracellular hemoglobin of Glossoscolex paulistus: Alkaline oligomeric dissociation

Texto completo
Autor(es):
Carvalho, Francisco Adriano O. [1] ; Santiago, Patricia S. [1] ; Borges, Julio C. [1] ; Tabak, Marcel [1]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Inst Quim Sao Carlos, Sao Paulo - Brazil
Número total de Afiliações: 1
Tipo de documento: Artigo Científico
Fonte: International Journal of Biological Macromolecules; v. 48, n. 1, p. 183-193, JAN 1 2011.
Citações Web of Science: 18
Resumo

The giant extracellular hemoglobin of Glossoscolex paulistus (HbGp) has a molecular mass (M) of 3600 +/- 100 kDa and a standard sedimentation coefficient (s(20.w)(0)) of 58 S. estimated by analytical ultracentrifugation (AUC). In the present work, further AUC studies were developed for HbGp, at pH 10.0, which favors oligomeric dissociation into lower M species. The HbGp oligomer is formed by globin chains a, b, c and d plus the linker chains. The pure monomeric fraction, subunit d, and HbGp at pH 10.0, in the presence of beta-mercaptoethanol, were also studied. Our results indicate that for samples of pure subunit d, besides the monomeric species with s(20.w)(0) of 2.0 S, formation of dimer of subunit d is observed with s(20.w)(0) of around 2.9 S. For the whole HbGp at pH 10.0 contributions from monomers, trimers and linkers are observed. No contribution from 58 S species was observed for the sample of oxy-HbGp at pH 10.0, showing its complete dissociation. For cyanomet-HbGp form a contribution of 17% is observed for the un-dissociated oligomer, consistent with data from other techniques that show the cyanomet-form is more stable as compared to oxy-HbGp. Masses of HbGp subunits, especially trimer abc and monomeric chains a, b, c and d, were also estimated from sedimentation equilibrium data, and are in agreement with the results from MALDI-TOF-MS. (C) 2010 Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 07/05001-4 - Estudos dos sistemas chaperones moleculares HSP70 e HSP90 de parasitas
Beneficiário:Julio Cesar Borges
Linha de fomento: Auxílio à Pesquisa - Apoio a Jovens Pesquisadores