构象性B细胞表位预测的免疫信息学方法及其网络资源

抗原表位预测是免疫信息学研究的重要方向之一,可以给实验提供重要的线索。B细胞表位或抗原决定簇是抗原中可被B细胞受体或抗体特异性识别并结合的部位。实际上,近90%的B细胞表位是构象性的。即使抗原蛋白质三级结构已知,B细胞表位预测仍然是一大挑战。该文结合实例阐述当今主要的构象性B细胞表位预测方法和算法:机器学习预测、非机器学习的计算预测、基于噬菌体展示数据的识别方法,以及一些也可用于构象性B细胞表位预测的通用蛋白质-蛋白质界面预测方法;介绍最新相关预测软件和Web服务资源,说明未来的研究趋势。     

The population biology of the acanthocephalan Pomphorhynchus laevis (Müller) in the River Avon

Regular samples of Gammarus pulex and dace Leuciscus leuciscus and occasional grayling Thymallus thymallus and chub L.cephalus were examined from the River Avon, Hampshire, for the presence of the acanthocephalan Pomphorhynchus leavis . The parasite only occurred in medium sized Gammarus due to lower probability of contact with small gammarids and stunted growth and selective mortality amongst older infected ones. No cycles in incidence or development of the parasite in G.pulex were observed. The parasite infected gammarids and grew in all months, and cystacanths were available throughout the year. Despite seasonal feeding activity and dietary preferences, fish fed on Gammarus and acquired infections in all months. Dispersion of P.laevis within the fish population was related to host feeding behaviour. No evidence of seasonal cycles in incidence or intensity of infection in fish was found, and observed monthly changes in the parasite population were related to changes in size structure of the host sample. In dace and grayling P.laevis grew little and matured only in summer, but in chub it grew and produced acanthors all year. The parasite population in fish appeared to be in a state of dynamic equilibrium and gain and loss of parasites took place throughout the year with the level of infection at any moment being determined primarily by the feeding behaviour of the host. This relationship between host diet, water temperature and parasite population size is discussed, and P.laevis in the R. Avon compared with other localities and other parasites.