A Stochastic Emergence Model: Accounting for Genetic Noise in the “Scout Cell Model” of Dormancy Emergence

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According to previous studies, microbial diversity in the environment is dictated by the presence of a large seed bank that continuously shifts metabolic activity depending on the environmental conditions. Previous models for the bacteria biodiversity equilibrium fail to realistically simulate the emergence of species from a dormant metabolic state. A posit as to why these models fail is that microbes break from dormancy in a stochastic pattern caused by genomic noise within a species, creating the phenomenon of scout cells. If the environment is favorable for these scout cells, then they will have the opportunity to release exogenous proteins that will trigger the activation of other cells. By examining sequenced cultured ultra micro-bacteria (∼20nm diameter) present in soils from the sample plot over two years, we created a model utilizing a total species list to suggest the statistical likelihood of stochastic emergence. The assumptions include the presence of some dormant cells in all populations; the presence of cells in a population always being available to switch metabolic states between active and inactive; and the necessity of a scout cell to survive in order to increase the likelihood of other members of its species to emerge. using this scout cell emergence model, we adjusted the best previously utilized models used to account for species non-dormant biodiversity.Key Words: Bacteria, Diversity, Genomic Noise, Emergence Model, Dormancy, Microbial Seed Bank