Microfluidics as tools to study soil bacteria

S. MONTAGNA; PIRES MONTEIRO M.; M. L. CORDERO; A.R. LODEIRO; V.I. MARCONI

Cordoba

Congreso; II Brazil-Argentine Microfluidics Congress; 2019

Some bacteria play a fundamental role both in our bodies and other organisms as well as in diverse ecosystems. They are extremely useful, for example for water and soil remediation and legume crops biofertilization (soybeans, peanuts, chickpeas) which supply the nitrogen needs. To understand the motility of bacteria in the soil can help to design better biotechnological solutions for this type of problem.Bradyrhizobium diazoefficiens is a soil bacteria used as soybean biofertilizer. They should move close to the roots for infection. Therefore, it is crucial to understand their motility properties in soil. It is challenging due to difficulty visualization in situ. With micro-devices, transparent and biocompatible it is pos- sible to observe the motility of bacteria in the laboratory in artificial porous media. In our project microfluidics play a key role as a new tool to study soil bacteria.We present a phenomenological model [Montagna, et. al., Anales AFA 2018] and numerical predictions of free and confined soil bacteria behavior. We use Langevin dynamics to solve the equations of motion and the key ingredient in our method is look for the best realistic motility parameters from experimental data analysis [Montagna, et. al., preprint 2019]. Simulations help to successfully design new experiments with lower costs and allow us to go further exploring geometries and times not reachable experimentally.Bacteria dynamics was studied in bulk and different networks of micro-channels achieving a numerical-experimental good agreement [Pires, Montagna, et. al., preprint 2019]. Our results help to understand the transport properties of B. dia- zoefficiens as a function of porosity. These contributions hopefully will be usefulfor further developments in sustainable agriculture.