Departamento de Microbiología, Instituto de Investigaciones Biológicas Clemente Estable, Avda. Italia 3318, C.P.11600 Montevideo, Uruguay.
Vet Microbiol. 2010 Mar 24;141(3-4):385-9. doi: 10.1016/j.vetmic.2009.09.006. Epub 2009 Sep 11.
American Foulbrood is a severe disease affecting larvae of honeybee Apis mellifera, causing significant decrease in the honeybee population, beekeeping industries and agricultural production. In spite of its importance, little is known about the virulence factors secreted by Paenibacillus larvae during larval infection. The aim of the present work was to perform a first approach to the identification and characterization of P. larvae secretome. P. larvae secreted proteins were analyzed by SDS-PAGE and identified by MALDI-TOF. Protein toxicity was evaluated using an experimental model based on feeding of A. mellifera larvae and immunogenicity was evaluated by Western blot, using an antiserum raised against cells and spores of P. larvae. Ten different proteins were identified among P. larvae secreted proteins, including proteins involved in transcription, metabolism, translation, cell envelope, transport, protein folding, degradation of polysaccharides and motility. Although most of these proteins are cytosolic, many of them have been previously detected in the extracellular medium of different Bacillus spp. cultures and have been related to virulence. The secreted proteins resulted highly toxic and immunogenic when larvae were exposed using an experimental model. This is the first description of proteins secreted by the honeybee pathogen P. larvae. This information may be relevant for the elucidation of bacterial pathogenesis mechanisms.
美洲幼虫腐臭病是一种严重影响蜜蜂幼虫的疾病，导致蜜蜂种群、养蜂业和农业生产的显著减少。尽管它很重要，但人们对幼虫感染期间蜡状芽孢杆菌分泌的毒力因子知之甚少。本工作旨在对蜡状芽孢杆菌分泌组进行初步鉴定和特性分析。通过 SDS-PAGE 分析蜡状芽孢杆菌分泌的蛋白质，并通过 MALDI-TOF 进行鉴定。使用基于喂养蜜蜂幼虫的实验模型评估蛋白质毒性，并用针对蜡状芽孢杆菌细胞和孢子的抗血清通过 Western blot 评估免疫原性。在蜡状芽孢杆菌分泌的蛋白质中鉴定出十种不同的蛋白质，包括参与转录、代谢、翻译、细胞包膜、运输、蛋白质折叠、多糖降解和运动的蛋白质。尽管这些蛋白质大多数存在于细胞质中，但其中许多已在不同芽孢杆菌属培养物的细胞外介质中检测到，并与毒力有关。当幼虫在实验模型中暴露于这些分泌蛋白时，它们表现出高度的毒性和免疫原性。这是对蜜蜂病原体蜡状芽孢杆菌分泌蛋白的首次描述。这些信息可能与阐明细菌发病机制有关。
