eng URI http://hdl.handle.net/10795/2623 βιολογία Conventional bacterial growth studies rely on large bacterial populations without considering the individual cells. Individual cells, however, can exhibit marked behavioral heterogeneity. Here, we present experimental observations on the colonial growth of 220 individual cells of Salmonella enterica serotype Typhimurium using time-lapse microscopy videos. We found a highly heterogeneous behavior. Some cells did not grow, showing filamentation or lysis before division. Cells that were able to grow and form microcolonies showed highly diverse growth dynamics. The quality of the videos allowed for counting the cells over time and estimating the kinetic parameters lag time ( ) and maximum specific growth rate ( max) for each microcolony originating from a single cell. To interpret the observations, the variability of the kinetic parameters was characterized using appropriate probability distributions and introduced to a stochastic model that allows for taking into account heterogeneity using Monte Carlo simulation. The model provides stochastic growth curves demonstrating that growth of single cells or small microbial populations is a pool of events each one of which has its own probability to occur. Simulations of the model illustrated how the apparent variability in population growth gradually decreases with increasing initial population size (N0). For bacterial populations with N 0 of >100 cells, the variability is almost eliminated and the system seems to behave deterministically, even though the underlying law is stochastic. We also used the model to demonstrate the effect of the presence and extent of a nongrowing population fraction on the stochastic growth of bacterial populations. 9 pp. LOMv1.0 creator LOMv1.0 publisher LOMv1.0 Project Final Beneficiary LOMv1.0 Project Executing Organisation 2012-11-23 Digital Library of the Operational Programme "Education and Lifelong Learning" abstract types Text Bacterial cells Individual cells Salmonella enterica Variability 1670284 application/pdf http://repository.edulll.gr/edulll/bitstream/10795/2623/2/2623_Deliverable%20%28%ce%a025%20-%20%ce%9451%29%20THALIS%20Biofilm%20MIS-380229%20AEM%2079%2c%202294.pdf Περιοδικό: Applied and Environmental Microbiology (AEM) URI http://hdl.handle.net/10795/2623 LOMv1.0creator 2016-04-13T12:33:40Z LOMv1.0validator 2016-04-13T12:33:40Z LOMv1.0 gre no no Copyright EYD-EPEDBM (Operational Programme "Education and Lifelong Learning")