To create and maintain such elaborated structures, a great deal of communication, regulations, mutual understanding, and cooperation takes place in bacterial
morphogenesis. Differentiation in such a bacterial body (as a body, not a population of cells) may proceed via genetically differing subclones fulfilling different roles, and appearing reproducibly at characteristic periods of cultivation [7–10]. Sophisticated networks of chemical signals [11–13], the scaffolding of extracellular matrix  and even cell-to-cell contacts [15, 16] may enable attaining and maintaining the integrity of the body. Research in this direction has been greatly accelerated in last two decades by the discovery of the phenomenon of quorum sensing (see [17–19]; for Serratia see ). Bacterial populations react to such Bucladesine order signals – and build multispecies bodies accordingly – in a context-dependent manner . see more A plethora of quorum-modulating signals, such as indole or furanole derivatives, was also described [12, 21, 22]. The study of model monoclonal populations may contribute to understanding colony morphogenesis, providing the possibility to examine how, and even why, bacteria exert themselves towards “”species-specific”" appearances. We have previously demonstrated that colonies of Serratia marcescens can be viewed as multicellular bodies with genuine
embryonic development . Colonies displayed finite growth and clone-specific formative processes; even a disorganized cell slurry (up to 107 cells) could establish a regular pattern and embark on a typical developmental pathway. Under standardized culture conditions on
rich semi-solid media, the final shape and patterning of bacterial bodies depended essentially on four initial settings: (1) amount, density, and distribution pattern of founder cells (2) the configuration Adenosine triphosphate of surrounding free medium (3) the presence and character of other bacterial bodies sharing the same niche (4) self-perception, resulting in delimitation towards other bodies Here we further investigate the development of bacterial bodies and their interaction with close or distant neighbors of identical, or different, clonal origin. We also CBL0137 research buy propose a formal model that can account for some of our experimental results. Results Colony patterning in clonal variants of Serratia rubidaea We have chosen a wild type strain of Serratia rubidaea, a Gram-negative, facultatively anaerobic, rod-shaped bacterium of the Enterobacteriaceae family (; see Methods), producing usually red glossy colonies without any distinguished structural pattern except of a slightly darker touch in the middle, as our starting material. This strain will be further referred to as the R (Red) strain.