Research Jeanine Geelhoed

Abstract

A prominent societal challenge is to ensure that electronic technology becomes more sustainable, and hence, material scientists are looking for radical alternatives to the electronic materials currently in use. Recent discoveries show that bacteria can produce "conductive silk", i.e., protein nanofibers with a high conductivity rivaling that of the most performant semi-conductor materials. This brings a long-time dream of material scientists within reach: to combine the unique traits of proteins fibers (flexible, lightweight, biocompatible, biodegradable, self-assembling) with high electronic functionality. The principal technological challenge is to produce these protein fibers in a controlled and scalable way. The goal of this FWO-SBO project is to mimic the self-assembly of these protein nanofibers under controlled in vitro conditions, allowing scalable recombinant production of conductive protein fibers in "microbial factories". To this end, we will develop pathways for synthetic self-assemblage of microbial conductive proteins as well as procedures for tuning the electronic properties of these synthetic protein fibers. As a proof of concept, we will integrate our custom-crafted synthetic conductive protein fibers into a simplified biodegradable electronic device. Our long-term technological vision is to achieve a radically new class of electronic materials that are bio-based. These so-called "proteonic fiber materials" will allow far more sustainable production and recycling pathways, thus creating major breakthroughs towards a circular and carbon-neutral economy (e.g. by reducing e-waste). Proteonic fiber materials have the potential to revolutionize applications in health care (electronic skin patches, metal-free implants), textile (smart clothing), packaging industry (biodegradable RFID tags), and environmental protection (dissolving bio-sensors).

Researcher(s)

• Promoter: Meysman Filip
• Co-promoter: Geelhoed Jeanine

Research team(s)

• Geobiology

Project type(s)

• Research Project

Abstract

Long filamentous cable bacteria are capable of generating and mediating electricity over centimeter-scale distances, thus extending the known length scale of biological electron transport by three orders of magnitude. Up until present, research efforts have concentrated on the cable bacteria themselves, yet recent data provide indications of a tight coupling between cable bacteria and associated microorganisms. Possible interactions include a mutualistic exchange of metabolic substrates (classical syntrophy) or, more intriguingly, indirect and direct mechanisms such as direct interspecies electron transfer or electron shuttles. In this project we will investigate the presence and nature of such interactions. Our hypothesis is that long-distance electron transport in aquatic sediments is not exclusively mediated by cable bacteria, but could involve a consortium of cable bacteria and associated partner microbes. Field sampling in marine and brackish environments will be combined with targeted incubation experiments in the laboratory. Next generation sequencing methods and microscopy will be applied, and correlation analysis will unravel associations between cable bacteria and other microbes. Metatranscriptomes will shed light on potential electric or metabolic interactions. The project will improve our understanding of electrogenic sediments, with potentially important implications for sediment biogeochemistry and microbial ecology.

Researcher(s)

• Promoter: Meysman Filip
• Co-promoter: Geelhoed Jeanine
• Co-promoter: Vasquez Cardenas Diana
• Fellow: Ley Philip

Research team(s)

• Geobiology

Project type(s)

• Research Project

Abstract

Recently, an entirely new type of bacteria has been discovered that can conduct high electrical currents over centimeters long distances via long, thin fibers embedded in the cell sheath. Recent studies show that these fibers have electrical abilities in power, including electrical conductivity data that exceeds that of all biological materials by orders of magnitude. The ambition of this project is to investigate investigate whether and how the fiber structures of cable bacteria can be used as components in a new generation of biocompatible and biodegradable electronic devices.

Researcher(s)

• Promoter: Meysman Filip
• Co-promoter: De Wael Karolien
• Co-promoter: Geelhoed Jeanine

Research team(s)

• Geobiology

Project type(s)

• Research Project