Affiliation:
1. School of Life Science BK21 FOUR KNU Creative BioResearch Group Kyungpook National University Daegu Republic of Korea
2. Systems Biology Department Centro Nacional de Biotecnología (CNB‐CSIC) Cantoblanco‐Madrid Spain
3. Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid (UPM)‐Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC) Madrid Spain
Abstract
AbstractColony formation is key to many ecological and biotechnological processes. In its early stages, colony formation involves the concourse of a number of physical and biological parameters for generation of a distinct 3D structure—the specific influence of which remains unclear. We focused on a thus far neglected aspect of the process, specifically the consequences of the differential pressure experienced by cells in the middle of a colony versus that endured by bacteria located in the growing periphery. This feature was characterized experimentally in the soil bacterium Pseudomonas putida. Using an agent‐based model we recreated the growth of microcolonies in a scenario in which pressure was the only parameter affecting proliferation of cells. Simulations exposed that, due to constant collisions with other growing bacteria, cells have virtually no free space to move sideways, thereby delaying growth and boosting chances of overlapping on top of each other. This scenario was tested experimentally on agar surfaces. Comparison between experiments and simulations suggested that the inside/outside differential pressure determines growth, both timewise and in terms of spatial directions, eventually moulding colony shape. We thus argue that—at least in the case studied—mere physical pressure of growing cells suffices to explain key dynamics of colony formation.
Funder
Comunidad de Madrid
Ministerio de Ciencia e Innovación
Subject
Agricultural and Biological Sciences (miscellaneous),Ecology, Evolution, Behavior and Systematics