High-throughput 96-well bioelectrochemical platform for screening of electroactive microbial consortia

Abstract

The development of bioelectrochemical systems reinforces the necessity for the identification and engineering of electroactive bacteria with improved performance and novel biochemical properties. In this study, using a newly designed 96-well-plate array of microbial fuel cells (MFCs), we compared the electroactive capabilities of microbial communities derived from four mine drainages. The maximum power density of individual wells after two weeks of inoculation was 102 mW/m 3 , whereas the maximum current density was 1.6 A/m 3 . Transferring communities from individual wells into larger MFCs comprising low (20 mg/L) and high (200 mg/L) concentrations of Cu yielded maximum power densities of 445 and 58 mW/m 3 , respectively, with up to a 3.7 fold decrease in Cu 2+ ions within 24 h. Electrochemical data analysis revealed that microbial consortia can be distinguished based on their electrochemical profiles. Our results showed that a 96-well MFC array is a suitable platform for high-throughput screening, selection, and subsequent source of enriched electroactive consortia. The quantitative and comparative analysis followed by principal component analysis indicated that the initial environmental conditions, as well as physical and chemical parameters of the lakes were crucial to develop an efficient electroactive community. Further applications of the proposed platform include genetic engineering, phenotype screening, and mutagenesis studies of both microbial communities and single cultures. This is the first time that a high-throughput MFC platform is used to evaluate the performance of multiple electroactive consortia towards Cu removal.

Multivariate landscapes constructed by Bayesian estimation over five hundred microbial electrochemical time profiles

“… 10 , 11 , 12 , 13 However, although significant development has been achieved in high-throughput BESs, there are no reports on a system that can achieve enough reproducibility while simultaneously controlling the following three parameters for each reactor: potential, electrolyte, and microorganism, which are critical for BES performance. 14 , 15 , 16 , 17 , 18 , 19 Furthermore, appropriate data processing algorithms for dealing with a large volume of current-time profile data have not been established yet. 18 Therefore, even in the most recent studies, the use of data science for the number of datasets used for training the model are very limited, at nine.…”

Novel species identification and deep functional annotation of electrogenic biofilms, selectively enriched in a microbial fuel cell array

“…Such problems could be avoided by using PCBs with the so-called hard gold finish (electrochemically plated gold) or by covering the PCB anode with other conductive materials, such as stainless steel sheets, thus protecting the underlying Cu from being oxidized. Indeed, the electrochemical plating of the PCB successfully prevented Cu leakage in our modified well plate (Szydlowski et al, 2022). Owing to this unexpected leakage of Cu ions, we successfully enriched the Cu-resistant communities using our 96-well platform.…”

“…Each well was built as an individual MFC with a membraneless design ( Figure 1 ), as described previously ( Szydlowski et al, 2022 ), with the following modifications: the base anode plate was built from a standard PCB comprising a thin copper sheet (17 μ m ) with electroless nickel plating and covered with a thin layer of immersion gold (ENIG—RoHS by JLCPCB, China). The seal was manufactured from polydimethylsiloxane (Sylgard 184; Sigma Aldrich) using a custom-made mold.…”

Prevention and removal of membrane and separator biofouling in bioelectrochemical systems: a comprehensive review

“…In slightly modified reactors, bioelectrochemical synthesis of valuable compounds takes place, known as microbial electrosynthesis or electrofermentation (Rabaey and Rozendal, 2010;Sonawane et al, 2021;Roy et al, 2022). BESs have also been used for water desalination, electrolysis for the production of hydrogen or methane, and the recovery of metals (Cao et al, 2009;Sleutels et al, 2012;Kokko et al, 2017;Szydlowski et al, 2022).…”