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Title: Population dynamics model and analysis for bacteria transformation and conjugation
Abstract

We present a two-species population model in a well-mixed environment where the dynamics involves, in addition to birth and death, changes due to environmental factors and inter-species interactions. The novel dynamical components are motivated by two common mechanisms for developing antibiotic resistance in bacteria: plasmidtransformation, where external genetic material in the form of a plasmid is transferred inside a host cell; andconjugationby which one cell transfers genetic material to another by direct cell-to-cell contact. Through analytical and numerical methods, we identify the effects of transformation and conjugation individually. With transformation only, the two-species system will evolve towards one species’ extinction, or a stable co-existence in the long-time limit. With conjugation only, we discover interesting oscillations for the system. Further, we quantify the combined effects of transformation and conjugation, and chart the regimes of stable co-existence, a result with ecological implications.

Authors:
; ;
Award ID(s):
1702321
Publication Date:
NSF-PAR ID:
10193532
Journal Name:
Journal of Physics Communications
Volume:
4
Issue:
9
Page Range or eLocation-ID:
Article No. 095021
ISSN:
2399-6528
Publisher:
IOP Publishing
Sponsoring Org:
National Science Foundation
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