The success of community information systems depends on a careful design of the digital media, and on the related tools for communication and collaboration. Particularly for the cultural sciences the community engine should be capable of supporting the discursive processes of hypermedia knowledge management and sharing. Information systems therefore need to reflect the underlying community processes through well adapted media sets of drawings, animations, pictures, digital video, text etc. The information system architecture ATLAS (Architecture for Transcription, Localization, and Addressing Systems) is based on a formalization of an operational media-theory and knowledge management theory for information systems. My work introduces the Lightweight Application Server (LAS), which is an infrastructure to support this formalization. LAS offers dedicated multimedia services for media centric work in communities on the basis of the multimedia content description interface MPEG-7. Besides its advanced multimedia support LAS offers extending and reloading of services at runtime, as well a role-based security concept. The introduced theory and the LAS have been evaluated in different information systems for cultural science communities in research and education.