Modelling the spatiotemporal complexity of interactions between pathogenic bacteria and a phage with a temperature-dependent life cycle switch

Abstract

We apply mathematical modelling to explore bacteria-phage interaction mediated by condition-dependent lysogeny, where the type of the phage infection cycle (lytic or lysogenic) is determined by the ambient temperature. In a natural environment, daily and seasonal variations of the temperature cause a frequent switch between the two infection scenarios, making the bacteria-phage interaction with condition-dependent lysogeny highly complex. As a case study, we explore the natural control of the pathogenic bacteria Burkholderia pseudomallei by its dominant phage. B. pseudomallei is the causative agent of melioidosis, which is among the most fatal diseases in Southeast Asia and across the world. We assess the spatial aspect of B. pseudomallei-phage interactions in soil, which has been so far overlooked in the literature, using the reaction-diffusion PDE-based framework with external forcing through daily and seasonal parameter variation. Through extensive computer simulations for realistic biological parameters, we obtain results suggesting that phages may regulate B. pseudomallei numbers across seasons in endemic areas, and that the abundance of highly pathogenic phage-free bacteria shows a clear annual cycle. The model predicts particularly dangerous soil layers characterised by high pathogen densities. Our findings can potentially help refine melioidosis prevention and monitoring practices.

Mathematical model of COVID-19 with comorbidity and controlling using non-pharmaceutical interventions and vaccination

“…This process helps to slow but not to stop the spread. The literature can be found to study the optimal control strategies [22][23][24][25][26][27]. Different mathematical models of epidemiology have been investigated with their corresponding transmission dynamics [28,29].…”

Generation of Distinct Differentially Culturable Forms of Burkholderia following Starvation at Low Temperature

“…In conclusion, we identified temperature as a factor that triggers the transition of Burkholderia into a differentially culturable state resulting in the generation of coccoid cells. A well-known seasonal charter of melioidosis has been linked to temperature ( 50 ) and our results reveal an additional temperature-dependent mechanism that may contribute to B. pseudomallei survival in the environment and influence infections in humans. The generation of DCB in B. pseudomallei can also explain the endemic nature of melioidosis, which is prevalent in tropical countries and rarely diagnosed in countries with a cold climate.…”

Characterization of Mu-Like Yersinia Phages Exhibiting Temperature Dependent Infection

“…When taken together with previous studies, our findings suggest that the phenomenon of temperature dependency in phages is not uncommon. Previous studies reported that in warm conditions the phages infect the pathogen and follow a lytic cycle (immediately killing the host cells), whereas at colder temperatures they lysogenize their bacterial hosts ( 28 ). It was speculated the phages entered the lytic state and lyse Y. pestis following the transition into a warm-blooded host, i.e., M. himalayana .…”