Busca avançada
Ano de início
Entree
(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.)

Cloning, purification and comparative characterization of two digestive lysozymes from Musca domestica larvae

Texto completo
Autor(es):
Cancado, F. C. [1] ; Effio, P. Chimoy [1] ; Terra, W. R. [1] ; Marana, S. R. [1]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Inst Quim, Dept Bioquim, BR-05513970 Sao Paulo - Brazil
Número total de Afiliações: 1
Tipo de documento: Artigo Científico
Fonte: Brazilian Journal of Medical and Biological Research; v. 41, n. 11, p. 969-977, NOV 2008.
Citações Web of Science: 17
Resumo

cDNA coding for two digestive lysozymes (MdL1 and MdL2) of the Musca domestica housefly was cloned and sequenced. MdL2 is a novel minor lysozyme, whereas MdL1 is the major lysozyme thus far purified from M. domestica midgut. MdL1 and MdL2 were expressed as recombinant proteins in Pichia pastoris, purified and characterized. The lytic activities of MdL1 and MdL2 upon Micrococcus lysodeikticus have an acidic pH optimum (4.8) at low ionic strength (mu = 0.02), which shifts towards an even more acidic value, pH 3.8, at a high ionic strength (mu = 0.2). However, the pH optimum of their activities upon 4-methylumbelliferyl N-acetylchitotrioside (4.9) is not affected by ionic strength. These results suggest that the acidic pH optimum is an intrinsic property of MdL1 and MdL2, whereas pH optimum shifts are an effect of the ionic strength on the negatively charged bacterial wall. MdL2 affinity for bacterial cell wall is lower than that of MdL1. Differences in isoelectric point (pl) indicate that MdL2 (pl = 6.7) is less positively charged than MdL1 (pl = 7.7) at their pH optima, which suggests that electrostatic interactions might be involved in substrate binding. In agreement with that finding, MdL1 and MdL2 affinities for bacterial cell wall decrease as ionic strength increases. (AU)

Processo FAPESP: 06/56521-5 - Bases moleculares das propriedades catalíticas das enzimas
Beneficiário:Sandro Roberto Marana
Linha de fomento: Auxílio à Pesquisa - Regular
Processo FAPESP: 01/07531-4 - Structural biology of proteins that may the be targets of insect control strategies
Beneficiário:Walter Ribeiro Terra
Linha de fomento: Auxílio à Pesquisa - Regular
Processo FAPESP: 04/02225-0 - Bases moleculares do efeito do pH na atividade catalítica de uma lisozima digestiva de Musca domestica L. (Diptera)
Beneficiário:Fabiane Chaves Cançado
Linha de fomento: Bolsas no Brasil - Doutorado Direto