Manipulating Bacterial Biofilms Using Materiobiology and Synthetic Biology Approaches

Abstract

Bacteria form biofilms on material surfaces within hours. Biofilms are often considered problematic substances in the fields such as biomedical devices and the food industry; however, they are beneficial in other fields such as fermentation, water remediation, and civil engineering. Biofilm properties depend on their genome and the extracellular environment, including pH, shear stress, and matrices topography, stiffness, wettability, and charges during biofilm formation. These surface properties have feedback effects on biofilm formation at different stages. Due to emerging technology such as synthetic biology and genome editing, many studies have focused on functionalizing biofilm for specific applications. Nevertheless, few studies combine these two approaches to produce or modify biofilms. This review summarizes up-to-date materials science and synthetic biology approaches to controlling biofilms. The review proposed a potential research direction in the future that can gain better control of bacteria and biofilms.

Keywords: bacteria; biofilm; extracellular matrix; gene editing; materiobiology.

FIGURE 1

Schematic illustration of the review. Bacteria can form biofilms once attached to a substrate that can be beneficial or problematic depending on specific situations. A thorough understanding of biofilm formation factors and their properties is necessary for better application. Both genomic modifications of the bacteria and substratum’s properties can affect biofilm’s properties. Currently, little research has focused on combining these two methods to control biofilm formation. In this article, we propose that by taking advantage of both synthetic biology and materiobiology, it is possible to gain better control over biofilm formation.

FIGURE 2

Studies focused on different substrate moduli ranges in bacteria adhesion.

FIGURE 3

(A) Nanopillared topography inhibited bacteria upstream motility indicated by single-cell trajectories. Single-cell trajectories of Pseudomonas naeruginosa on the flat surfaces originated from 0 and extended to the –80 μm in x-direction indicating upstream motility, while much less motility distance was observed on a nanopillar topography (P500). The black ring is 10 μm radium as a reference (Rosenzweig et al., 2019). Adapted with permission from Rosenzweig et al. (2019). Copyright 2019 American Chemical Society. (B) Hemisphere topography affected bacterial migration. Fluorescence images showing P. aeruginosa movement traces. It showed bacteria appear to explore a smaller fraction of the flat surface compared with hemisphere topography surfaces with 2–8 μm features (Yow-Ren Chang and Ducker, 2018). Adapted with permission from Yow-Ren Chang and Ducker (2018). Copyright 2018 American Chemical Society. (C) Conjugation frequency and biofilm formation of Escherichia coli were influenced by surface topography. The square-shaped pattern showed higher conjugation frequency than smooth and hexagon-shaped surfaces (Gu et al., 2017). Adapted with permission from Gu et al. (2017). Copyright 2017 American Chemical Society. (D) Representative images of Vibrio cholerae biofilm grown on different substrates at different time points. Blue dotted circles mark the boundaries of regions with radical patterns, and red dotted circles mark the boundaries of regions with zigzag patterns. It showed biofilm morphology differed on different substrate’ stiffness (Fei et al., 2020). Adapted with permission from Fei et al. (2020). Copyright 2020 National Academy of Science.

FIGURE 4

(A) Topography affecting multispecies biofilm morphology and species content where green and red colors indicate Escherichia coli and Pseudomonas aeruginosa, respectively. The fraction of E. coli in the co-cultured film increased with the pillar height (Bhattacharjee et al., 2017). Adapted with permission from Bhattacharjee et al. (2017). Copyright 2017 American Chemical Society. (B) The effect of magnetically driven dynamic pillar pattern on biofilm formation. (i) Schematic image of pillar bending in response to an external magnetic field. (ii) Fluorescent images of the pillar before and after exposure to a magnetic field. (iii) Representative fluorescence images of biofilms on flat controls, static controls, and active surface topographies (Gu et al., 2020). Adapted with permission from Gu et al. (2020). Copyright 2020 Spring Nature. (C) The effect of shape recovery substrate on biofilm formation. (i) Schematic illustration of dynamic substrates. (ii) Biofilm staining on different dynamic substrates. (iii) Detached bacteria were more susceptible to antibiotics on dynamic substrates (Lee et al., 2021).