FluxMap: A VANTED add-on for the visual exploration of flux distributions in biological networks

We present FluxMap, a tool for the advanced visualization and exploration of flux data in the context of metabolic networks. The template-based flux data import assigns flux values and optional quality parameters (e. g. the confidence interval) to biochemical reactions. It supports the discrimination between mass and substance fluxes, such as C- or N-fluxes. After import, flux data mapping and network-based visualization allow the interactive exploration of the dataset. Various visualization options enable the user to adapt layout and network representation according to individual purposes.The Vanted add-on FluxMap comprises a comprehensive set of functionalities for visualization and advanced visual exploration of flux distributions in biological networks. It is available as a Java open source tool from http://www.vanted.org/fluxmap.Metabolic flux analysis is becoming increasingly important for the understanding of the dynamics of metabolic networks [1]. Flux values can be derived from wetlab experiments, e. g. using stable isotopic tracers (such as 13？C-Metabolic Flux Analysis), or from drylab computational approaches, such as Flux Balance Analysis (see, for example, [2].) Based on comparative flux analysis conclusions can be drawn about the influence of internal or external parameters on the metabolic behavior of a biological system. The visualization of fluxes in the context of metabolic networks supports such analysis. Firstly, images are a convenient way of communicating information to the scientist and, secondly, visual analysis of network-associated fluxes is intuitive for the user. Thirdly, especially for flux distributions in large networks, flux visualization enables data interpretation on a global level and facilitates the gain of knowledge. As an extension to network-based flux visualization, interactive exploration techniques provide the basis for an easy and fast comparison of different flux distributions, which would be very elaborate when working wi