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17. HOME: Wood-Mycelium Composites for CO2-Neutral, Circular Interior Construction and Fittings

Author

Rossi, Andrea, Javadian, A, Acosta, I, Özdemir, E, Nolte, N, Saeidi, N, Dwan, A, Ren, S, Vries, L, Hebel, D, Wurm, Jan, Eversmann, P, Rossi, Andrea, Javadian, Acosta, Ozdemir, Nolte, Saeidi, Dwan, Ren, Vries, and Hebel

Subjects
General Medicine, General Chemistry
Abstract

Office and retail interior fittings have a relatively short service life of 5-7 years. In this context, composite materials are often used, hindering possibilities of reuse or recycling. This research explores novel bio-composite materials and subsequently a construction method for CO2-neutral, circular interior fittings for office spaces. Based on the potential of fungal mycelium as a rapidly renewable, regenerative, affordable, low-carbon building material, bio-composite construction methods are explored in conjunction with timber-based additive manufacturing using continuous fibres. As mycelium has potentially excellent sound-absorbing properties but low load-bearing capacity, composite construction of timber veneer and mycelium allows to increase the structural capabilities of resulting components, while relying entirely on bio-based value chains. We describe the production process as well as the material development, including robotically aided processes for additive manufacturing of veneer reinforcement grids and compatibility studies of different mycelial species and substrates, and their bonding capabilities with veneer. We further present initial results on the mechanical characterization of the composite material, and its comparison to conventional mycelium composites. Minimal structural, acoustic, and functional requirements for different interior fitting elements are studied and compared to the characteristics of the proposed composite, highlighting the range of applications of the presented wood-mycelium composites.

Published
2022

24. Crystal structure of the translation recovery factor Trf from Sulfolobus solfataricus

Author

Kaiser, Marco, Wurm, Jan Philip, Märtens, Birgit, Bläsi, Udo, Pogoryelov, Denys, and Wöhnert, Jens

Subjects
ddc:570
Abstract

During translation initiation, the heterotrimeric archaeal translation initiation factor 2 (aIF2) recruits the initiator tRNAi to the small ribosomal subunit. In the stationary growth phase and/or during nutrient stress, Sulfolobus solfataricus aIF2 has a second function: It protects leaderless mRNAs against degradation by binding to their 5′‐ends. The S. solfataricus protein Sso2509 is a translation recovery factor (Trf) that interacts with aIF2 and is responsible for the release of aIF2 from bound mRNAs, thereby enabling translation re‐initiation. It is a member of the domain of unknown function 35 (DUF35) protein family and is conserved in Sulfolobales as well as in other archaea. Here, we present the X‐ray structure of S. solfataricus Trf solved to a resolution of 1.65 Å. Trf is composed of an N‐terminal rubredoxin‐like domain containing a bound zinc ion and a C‐terminal oligosaccharide/oligonucleotide binding fold domain. The Trf structure reveals putative mRNA binding sites in both domains. Surprisingly, the Trf protein is structurally but not sequentially very similar to proteins linked to acyl‐CoA utilization—for example, the Sso2064 protein from S. solfataricus—as well as to scaffold proteins found in the acetoacetyl‐CoA thiolase/high‐mobility group‐CoA synthase complex of the archaeon Methanothermococcus thermolithotrophicus and in a steroid side‐chain‐cleaving aldolase complex from the bacterium Thermomonospora curvata. This suggests that members of the DUF35 protein family are able to act as scaffolding and binding proteins in a wide variety of biological processes.

Published
2019

33. The structure of the SAM/SAH-binding riboswitch

Author

Weickhmann, A Katharina, primary, Keller, Heiko, additional, Wurm, Jan P, additional, Strebitzer, Elisabeth, additional, Juen, Michael A, additional, Kremser, Johannes, additional, Weinberg, Zasha, additional, Kreutz, Christoph, additional, Duchardt-Ferner, Elke, additional, and Wöhnert, Jens, additional

Published
2018
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36. Conformational Modulation of a Mobile Loop Controls Catalysis in the (βα)8-Barrel Enzyme of Histidine Biosynthesis HisF

Author

Hupfeld, Enrico, Schlee, Sandra, Wurm, Jan Philip, Rajendran, Chitra, Yehorova, Dariia, Vos, Eva, Ravindra Raju, Dinesh, Kamerlin, Shina Caroline Lynn, Sprangers, Remco, and Sterner, Reinhard

Abstract

The overall significance of loop motions for enzymatic activity is generally accepted. However, it has largely remained unclear whether and how such motions can control different steps of catalysis. We have studied this problem on the example of the mobile active site β1α1-loop (loop1) of the (βα)8-barrel enzyme HisF, which is the cyclase subunit of imidazole glycerol phosphate synthase. Loop1 variants containing single mutations of conserved amino acids showed drastically reduced rates for the turnover of the substrates N′-[(5′-phosphoribulosyl) formimino]-5-aminoimidazole-4-carboxamide ribonucleotide (PrFAR) and ammonia to the products imidazole glycerol phosphate (ImGP) and 5-aminoimidazole-4-carboxamide-ribotide (AICAR). A comprehensive mechanistic analysis including stopped-flow kinetics, X-ray crystallography, NMR spectroscopy, and molecular dynamics simulations detected three conformations of loop1 (open, detached, closed) whose populations differed between wild-type HisF and functionally affected loop1 variants. Transient stopped-flow kinetic experiments demonstrated that wt-HisF binds PrFAR by an induced-fit mechanism whereas catalytically impaired loop1 variants bind PrFAR by a simple two-state mechanism. Our findings suggest that PrFAR-induced formation of the closed conformation of loop1 brings active site residues in a productive orientation for chemical turnover, which we show to be the rate-limiting step of HisF catalysis. After the cyclase reaction, the closed loop conformation is destabilized, which favors the formation of detached and open conformations and hence facilitates the release of the products ImGP and AICAR. Our data demonstrate how different conformations of active site loops contribute to different catalytic steps, a finding that is presumably of broad relevance for the reaction mechanisms of (βα)8-barrel enzymes and beyond.

Published
2024
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37. Crystal structure of the translation recovery factor Trf from Sulfolobus solfataricus.

Author

Kaiser, Marco, Wurm, Jan Philip, Märtens, Birgit, Bläsi, Udo, Pogoryelov, Denys, and Wöhnert, Jens

Subjects
SCAFFOLD proteins, CRYSTAL structure, CARRIER proteins, OLIGONUCLEOTIDES, ZINC ions, TRANSLATIONS, ZINC porphyrins, ACYLTRANSFERASES
Abstract

During translation initiation, the heterotrimeric archaeal translation initiation factor 2 (aIF2) recruits the initiator tRNAi to the small ribosomal subunit. In the stationary growth phase and/or during nutrient stress, Sulfolobus solfataricus aIF2 has a second function: It protects leaderless mRNAs against degradation by binding to their 5′‐ends. The S. solfataricus protein Sso2509 is a translation recovery factor (Trf) that interacts with aIF2 and is responsible for the release of aIF2 from bound mRNAs, thereby enabling translation re‐initiation. It is a member of the domain of unknown function 35 (DUF35) protein family and is conserved in Sulfolobales as well as in other archaea. Here, we present the X‐ray structure of S. solfataricus Trf solved to a resolution of 1.65 Å. Trf is composed of an N‐terminal rubredoxin‐like domain containing a bound zinc ion and a C‐terminal oligosaccharide/oligonucleotide binding fold domain. The Trf structure reveals putative mRNA binding sites in both domains. Surprisingly, the Trf protein is structurally but not sequentially very similar to proteins linked to acyl‐CoA utilization—for example, the Sso2064 protein from S. solfataricus—as well as to scaffold proteins found in the acetoacetyl‐CoA thiolase/high‐mobility group‐CoA synthase complex of the archaeon Methanothermococcus thermolithotrophicus and in a steroid side‐chain‐cleaving aldolase complex from the bacterium Thermomonospora curvata. This suggests that members of the DUF35 protein family are able to act as scaffolding and binding proteins in a wide variety of biological processes. [ABSTRACT FROM AUTHOR]

Published
2020
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38. 'No Naked Nudes' series

Author

Wurm, Jan

Subjects
Women artists -- Aims and objectives, Women artists -- Beliefs, opinions and attitudes, Nude in art -- Appreciation, Nude in art -- Personal narratives, Nude in art -- Censorship, Art -- Exhibitions, Art -- Personal narratives, Art -- Social aspects, Women's issues/gender studies
Abstract

A woman artist asserts that her exhibition of drawings is an effort to visually seek form and expression in the nude. She also claims that she has been influenced by contrasting trends regarding art and the public. These trends are the public denial of the propriety of nude in art and the heightened interest of the public on life drawings.

Published
2009

48. Structure and Biophysical Characterization of the S-Adenosylmethionine-dependent O-Methyltransferase PaMTH1, a Putative Enzyme Accumulating during Senescence of Podospora anserina

Author

Chatterjee, Deep, primary, Kudlinzki, Denis, additional, Linhard, Verena, additional, Saxena, Krishna, additional, Schieborr, Ulrich, additional, Gande, Santosh L., additional, Wurm, Jan Philip, additional, Wöhnert, Jens, additional, Abele, Rupert, additional, Rogov, Vladimir V., additional, Dötsch, Volker, additional, Osiewacz, Heinz D., additional, Sreeramulu, Sridhar, additional, and Schwalbe, Harald, additional

Published
2015
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