Innovative bioinspired strategies towards selective lanthanide complexation and separation: From bacterial chelators to applications.

Project Information

LANTHANOPHOR

Grant agreement ID: 945846

DOI

10.3030/945846

EC signature date 20 August 2020

Start date 1 November 2020

End date 31 October 2026

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 1 496 935,00

EU contribution

€ 1 496 935,00

Coordinated by

HEINRICH-HEINE-UNIVERSITAET DUESSELDORF
Germany

Periodic Reporting for period 3 - LANTHANOPHOR (Innovative bioinspired strategies towards selective lanthanide complexation and separation: From bacterial chelators to applications.)

Reporting period: 2023-10-01 to 2025-03-31

Summary of the context and overall objectives of the project

We all need Lanthanides (Ln) in our daily life: they are essential for clean technologies, high-tech, medicine, agriculture and many more sectors. But, they are critical raw materials and designated with a high supply risk by the European Commission. Their mining and purification have a considerable negative environmental impact and thus we urgently need sustainable and efficient recycling strategies for these elements. In the last decade it was discovered, that many bacteria use Ln for growth and utilize them in the active sites of enzymes. In addition, Ln-binding proteins with unprecedented affinities for Ln (Lanmodulin, LanM) have been isolated from bacteria. The Ln-uptake mechanisms of these bacteria remain vastly underexplored, however, the involvement of polydentate ligands (chelators) to bind lanthanides — lanthanophores (lanthanide carriers) — has recently been established. For the first time, practical applications of chelators that were specifically designed by nature to bind, recycle and separate the technologically-indispensable lanthanides are in reach. Thus, the objective of LANTHANOPHOR is the identification and isolation of lanthanophores from the spent media of lanthanide-utilizing bacteria and the synthesis of short peptides based on the Ln-binding moiety in LanM.
We believe the development of sustainable solutions and bioinspired applications are urgently needed in the quest for new, environmentally friendly and faster Ln separation and recycling technologies.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

We have already thoroughly investigated the differences in Ln binding of LanM and short peptides. We showed, that LanM has a preference for Neodymium (the technological important lanthanide used in the strongest magnets known to man) and americium (a radioactive actinide with similar ionic radius to Neodymium). The short peptides based on the metal binding sites in LanM have a lower affinity for lanthanides but still a high selectivity over calcium.
Currently, a comprehensive characterization of the lanthanophore including its lanthanide coordination chemistry, is underway. The lanthanophore and the peptides are evaluated for the use in Ln separation and recycling. We are also looking deeper into the mechanism in which bacteria discriminate lanthanides (or f-elements in general, also including actinides); if we understand how nature does this, we can develop similar approaches to help us with the recycling of these crucial elements

Specifically:

Helena Singer, Robin Steudtner, Ignacio Sottorff, Björn Drobot, Arjan Pol, Huub J.M Op den Camp and Lena J. Daumann
Learning from Nature: Recovery and Recycling of rare earth elements by the extremophilic bacterium Methylacidiphilum fumariolicum, accepted pioneering investigator issue, Cover feature, Chem. Comm. 2023, in production https://pubs.rsc.org/doi/D3CC01341C
This article describes and in-depth investigation of the capabilities to use bacteria to separate and recycle lanthanides. We have tested several mining wastewaters, Lanthanide containing End of life waste and minerals. Our bacterium was able to selectively catch the early lanthanides form these mixtures.

Helena Singer, Robin Steudtner, Andreas S. Klein, Carolin Rulofs, Cathleen Zeymer, Björn Drobot, Arjan Pol, N. Cecilia Martinez-Gomez, Huub J. M. Op den Camp, Lena J. Daumann, Minor Actinides Can Replace Essential Lanthanides in Bacterial Life First published: 19 April 2023 https://doi.org/10.1002/anie.202303669 VIP Article
This article describes how bacteria can make use of not only lanthanides, the 4-f elements, but also radioactive 5-f elements! This helps us understand what is important for selective uptake. Here, it seems to be driven by size of the elements and oxidation state. It is the first time, that it was shown that actinides can have a biological role. Find a press release to read more here: https://onlinelibrary.wiley.com/page/journal/15213773/homepage/press/202321press.html

Alexa M Zytnick, Nathan Michael Good, Colin C Barber, Manh Tri Phi, Sophie M. Gutenthaler, Wenjun Zhang, Lena J. Daumann, Norma Cecilia Martinez-Gomez Identification of a biosynthetic gene cluster encoding a novel lanthanide chelator in Methylorubrum extorquens AM1, bioRxiv 2022 https://doi.org/10.1101/2022.01.19.476857
Here a first biosynthetic cluster for a lanthanophore is described. We synthesized different chelators and tested whether these would be structurally similar.

Sophie M. Gutenthaler, Satoru Tsushima, Robin Steudtner, Manuel Gailer, Anja Hoffmann-Röder, Björn Drobot*, Lena J. Daumann*, LanM Peptides – Unravelling the Binding Properties of the EFHand Loop Sequences Stripped from the Structural Corset, Inorg. Chem. Front., 2022, 9, 4009-4021
LanM is a protein with high affinity for Lanthanides and actinides. Here, we looked closer at the EF-Hands, the metal binding sites of this protein detached form cooperative binding.

H. Singer, B. Drobot, C. Zeymer, R. Steudtner*, L. J. Daumann* Americium preferred: Lanmodulin, a natural lanthanide-binding protein favors an actinide over lanthanides, Chem. Sci., 2021,12, 15581-15587
LanM was shown to have not only exceptional binding capabilities for lanthanides, but also actinides. The affinity of lanthanides follows a remarkable trend, with Neodymium being one of the best binding lanthanides.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Here, we have recently shown, that bacteria can use other f-elements for life. This is an important consideration when it comes for example to the recycling of nuclear waste (which contains a mixture of lanthanides and actinides). By the end of the project we expect to have fully characterized the first lanthanophore and developed a synthesis for this new, previously unknown chelator.

Summary of ERC Project Lanthanophore