As Grid technologies get practical, a number of Grid Portals have been constructed and used in various fields to offer user friendly interfaces for Grid resources. Along with that, several toolkits to generate Grid portals have been developed in order to reduce the burden of portal developers. However, even with the aid of those toolkits, portal developers still have to install target applications on each node. In addition to that, it is necessary to keep application data up to date for some applications, especially applications in bioinformatics field. In order to automate these tasks, we are implementing a toolkit, PCT4G, which automatic application installation and data management. Also, users can construct Grid Portals of their own applications on the fly through Web interfaces of PCT4G.