Selenium and tellurium in biocatalytic redox reactions
Selenium and tellurium sit at a promising intersection of trace-element biochemistry and industrial biocatalysis. Their redox versatility enables selective oxidation and reduction, potentially replacing harsher reagents and shortening routes to valuable chemicals.
Researchers gathered at the 16th International Symposium on Applied Bioinorganic Chemistry in Ioannina, Greece, in June 2023. Organised by the University of Ioannina, the meeting connected laboratory investigation with industrial applications in pharmaceuticals, agriculture and chemical manufacturing.
Young scientist travel awards, poster prizes and scholarships created practical entry points for participants, including researchers from Australia, where travel distances can shape collaboration. The programme welcomed people working across enzyme engineering, synthetic biology and chemical manufacturing.
Zita Congress & Event Management served as the official secretariat for registration, accommodation and abstract-related enquiries. This support helped the interdisciplinary gathering welcome established researchers, postgraduate candidates and scientists entering the field for the first time.
Why selenium and tellurium attract biocatalysts
Both elements access multiple oxidation states, but their biological roles and coordination behaviour differ. Selenium is essential in selenoproteins, including glutathione peroxidases and thioredoxin reductases, where redox control protects cells from oxidative stress. By contrast, tellurium has no widely established role in natural enzymes, leaving more room for discovery.
Synthetic enzymes can use these elements to tune electronics, substrate recognition and electron, hydrogen or radical transfer. Potential applications include alcohol oxidation, thiol-disulfide exchange and selective reduction of unsaturated bonds under mild aqueous conditions. Redox-active mediators can extend the range of reactions available to whole cells.
These systems suit whole-cell biocatalysis, where conventional oxidants or metal catalysts can be costly, persistent and difficult to separate. Researchers must balance catalytic activity against toxicity, product purity and catalyst recovery, especially when moving from a laboratory flask to a fermenter.
Mechanistic routes for redox biocatalysis
Enzyme design depends on the mechanism: electron density, radical intermediates and the environment around the catalytic centre. Selenium-containing active sites often support thiol or selenol chemistry. Tellurium can facilitate bond formation through hypervalent intermediates and reversible redox cycling.
Protein engineering, directed evolution and mechanistic spectroscopy can improve turnover and selectivity together. Researchers should connect microscopic observations, such as shifts in redox potential, with conversion, enantioselectivity, catalyst lifetime and space-time yield.
Process constraints shape translation as much as molecular performance. Cofactor recycling, oxygen supply, substrate solubility and downstream separation can determine whether a promising reaction supports fine-chemical production at industrially relevant concentrations, particularly within a biologically demanding fermentation.
From Ioannina ideas to collaborative programmes
The 16th symposium brought inorganic chemists, enzymologists and bioprocess developers into the same conversation. Its Ioannina setting highlighted how trace-element chemistry, oxidative-stress biology and enzyme engineering can converge around practical catalytic pathways.
The symposium programme sets out the session framework, from fundamental catalyst design to bioprocess questions. For attendees, the value lay in connecting complementary expertise: chemists could contribute active-site motifs, while microbiologists and biochemical engineers addressed how catalytic systems perform beyond purified enzymes.
Awards, participation and shared resources
Participation included young scientist travel awards, poster prizes and scholarships. These routes support researchers facing the practical obstacles of international attendance, particularly the cost and coordination of travel, temporary accommodation and the time required to present unfamiliar work across disciplines.
Background on applied bioinorganic chemistry is available through the linked resources, helping readers place Ioannina within the field’s development. Applicants should check the official eligibility and documentation requirements for travel awards and scholarships before submitting their material.
Biocatalysis within Australia’s research landscape
Australian laboratories can contribute through enzyme discovery, protein engineering and process modelling. Melbourne and Sydney host university and industry clusters where biocatalysis teams can connect with pharmaceutical, synthetic-biology and advanced-materials companies, while researchers elsewhere build links through interstate collaboration.
Travel geography also affects participation. Delegates from Brisbane, Adelaide or Perth may connect through Melbourne or Sydney. Australian researchers should plan around the June calendar and travel-award timelines, leaving margin for visa processing, laboratory cover and transfers.
Customs and biosecurity deserve attention before samples, cultures or chemicals travel. Australia’s clean-clothing and footwear rules apply at airport entry, and biological materials, food products or soil may require permits and declarations, with rules differing between states. Chemical consignments need accurate identity and hazard descriptions.
Australia’s wheat and livestock industries make trace mineral nutrition commercially relevant, while the national market for selenium supplements and fortified products raises quality and consistency questions. Australian Research Council schemes and university fellowships offer familiar funding routes, and partnerships with manufacturers and agricultural scientists can test whether a proposed enzyme application meets genuine market and processing needs.
Research priorities and practical comparisons
A useful research agenda balances molecular insight with industrial relevance. The following priorities help teams identify reactions where element-enabled enzymes could deliver measurable value.
- Prioritise reactions with clear selectivity gains, lower reagent loading and compatible substrate concentrations.
- Compare enzyme and chemical routes using solvent use, energy demand, catalyst loading and waste treatment.
- Track stability, product carry-over and the fate of organoselenium or organotellurium by-products.
Industry collaboration often reveals bottlenecks missed by academic screening. A second checklist helps researchers present their work and funding needs clearly.
- Frame posters around one mechanistic insight and one application-relevant outcome.
- Match each application to the appropriate award, scholarship or poster opportunity.
- Prepare concise notes on analytical methods, reproducibility and scale-up constraints.
The two elements present different scientific starting points:
| Dimension | Selenium-enabled catalysis | Tellurium-enabled catalysis |
|---|---|---|
| Biological foundation | Well established through selenoproteins in humans and other organisms | Little established precedent, with most work focused on synthetic systems |
| Distinctive chemistry | Thiol and selenol oxidation, reductive protection and electron transfer | Hypervalent intermediates and access to multiple oxidation states |
| Development priority | Improve activity, selectivity and stability within engineered enzyme scaffolds | Establish useful activity and selectivity with rigorous toxicity controls |
| Scale-up questions | Enzyme loading, cofactor balance, by-product fate and product recovery | Catalyst availability, mediator use, by-product recovery and toxicity assessment |
Act on the collaboration
The 16th International Symposium on Applied Bioinorganic Chemistry showed how elemental chemistry can become a platform for biocatalytic innovation. Its exchange of methods and priorities offers a foundation for projects that connect molecular control with credible process outcomes.
Researchers can use the symposium materials to identify collaborators, match award and scholarship routes to their circumstances and frame a focused abstract on redox enzyme design. Prospective delegates should review the official participation requirements and contact Zita Congress & Event Management for registration, accommodation and abstract-related enquiries.