Autor(es): Hirai, M; Kiuchi, M; Wang, J; Ishii, A; Matsuoka, H

Resumo: Kynurenine 3-hydroxylase (K3H) is a NADPH-dependent flavin monooxygenase involved in the tryptophan pathway. Xanthurenic acid (XA) is a metabolite of this pathway and has recently been identified as a gamete activating factor (GAF) of the malarial parasite. We cloned K3H cDNA from Anopheles stephensi (AsK3H), because anopheline mosquitoes are a vector of the human malaria parasite, Plasmodium falciparum and the catalytic function of AsK3H in XA production. Recombinant AsK3H protein was expressed in Sf-9 cells using the baculovirus system and its enzymatic properties were characterized. The specific activities of crude cell lysate and affinity purified protein were 94.9 +/- 6.2 and 865.6 +/- 10.5 nmol/min/mg protein, respectively. The optimum pH of AsK3H was 7.0. Analysis of AsK3H gene expression using RT-PCR revealed that AsK3H was constitutively expressed in egg, larva, pupa and adult.

Palavras-Chave: Kynurenine 3-hydroxylase; Anopheles stephensi; Xanthurenic acid; cDNA cloning

Imprenta: Insect Molecular Biology, v. 11, n. 5, p. 497-504, 2002

Identificador do objeto digital: 10.1046/j.1365-2583.2002.00358.x

Descritores: Aedes aegypti - RT-PCR

Data de publicação: 2002

INDICADORES

ACESSO