Article
Chemistry, Multidisciplinary
Carolin Dusold, Corinna Weiss, Frank Hampel, Andreas Hirsch
Summary: This study presents an unprecedented library of single and double bay-substituted perylene-pentaphenylbenzenes (PPBs), confirming extreme core-distortion and successful elimination of aggregation interactions of perylenes through X-ray analysis. Isomerically pure perylene-PPB hybrids exhibit remarkable differences in their photophysical properties with respect to their regiochemistry and peri-functionalization.
CHEMICAL COMMUNICATIONS
(2021)
Article
Biochemistry & Molecular Biology
Kazunori K. Fujii, Yuki Taga, Yusuke K. Takagi, Ryo Masuda, Shunji Hattori, Takaki Koide
Summary: Procollagen forms a triple helix structure in the endoplasmic reticulum with post-translational modifications enhancing its thermal stability. Collagen properties remain constant at lower temperatures, but at higher temperatures, an increase in post-translational modifications leads to higher thermal stability.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Tomas Fiala, Emilia P. Barros, Marc-Olivier Ebert, Enrico Ruijsenaars, Sereina Riniker, Helma Wennemers
Summary: This study reveals the significant impact of terminal residues on the stability of collagen model peptides (CMPs). By combining various experimental and simulation techniques, the researchers demonstrate how peptide termini preorganize into a polyproline-II helical structure and affect the stability of triple helices. These findings have important implications for designing peptide mimics of structural proteins and provide a straightforward method to tune the stability of CMPs for various applications.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Engineering, Biomedical
Jean -Daniel Malcor, Frederic Mallein-Gerin
Summary: This review article discusses the use of triple-helical peptides as efficient tools to improve cell-biomaterial interactions in tissue engineering. Triple-helical peptides are bioactive molecules that mimic the architectural and biological properties of collagen. They have been successfully used to specifically recognize cell-surface receptors and provide cells seeded on biomaterials with controlled biological cues. Functionalization with triple-helical peptides has enabled researchers to improve cell function for regenerative medicine applications, such as tissue repair. However, this approach still remains under-explored and most functionalization strategies reported in the literature are unable to address collagen-binding receptors.
ACTA BIOMATERIALIA
(2022)
Article
Chemistry, Multidisciplinary
Xiaojing Li, Qi Zhang, S. Michael Yu, Yang Li
Summary: Collagen provides support for human tissues and its damage can now be assessed through collagen hybridization. This research describes the development of collagen hybridization and the underlying rules of collagen triple-helix folding. It also discusses the biomedical evidence of collagen denaturation as an ECM signature for tissue remodeling and injuries, and proposes new questions and opportunities for diagnostic and therapeutic advancements.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemistry & Molecular Biology
Tsai-Ling Hsu, Jia-Cherng Horng
Summary: The incorporation of Thp into collagen shows position-dependent effects on the stability of the triple helix structure, with a larger destabilization effect observed when Thp is substituted at the Y position. Furthermore, the oxidized derivatives of Thp also affect collagen stability, with a greater destabilization effect observed for derivatives at the Y position. Computational analysis suggests that the ease of interconversion between puckers and the twist conformation of S,S-dioxide Thp contribute to the destabilization effect at the Y position. This study provides new insights into the use of Thp and its derivatives for designing collagen-related biomaterials.
Article
Chemistry, Analytical
Ke Li, Delai Kang, Yu Li, Weizhe Zhu, Lian Zhu, Juntao Zhang, Chengzhi Xu, Benmei Wei, Haibo Wang
Summary: In this study, a quantitative determination method for collagen triple helix integrity was developed using bovine skin collagen peptide-protected Au/Ag nanoclusters as a fluorescent probe.
ANALYTICA CHIMICA ACTA
(2023)
Article
Biochemistry & Molecular Biology
Caihong Fu, Wenhua Li, Xiuxia Sun, Jianxi Xiao
Summary: The role of concentration in the stability of collagen peptides was investigated through the study of folding and unfolding features of collagen mimetic peptides at different concentrations. It was found that concentration plays a critical role in maintaining the triple helix structure and stability of collagen peptides.
PROTEIN AND PEPTIDE LETTERS
(2023)
Article
Biochemical Research Methods
Shogo Matsubara, Yui Okamoto, Masaru Yoshikawa, Shinya Tsukiji, Masahiro Higuchi
Summary: In this study, a peptide nanocage composed of an oligoproline conjugate was successfully prepared, showing easy preparation and high biocompatibility.
BIOCONJUGATE CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Jasmine Egli, Carmen Esposito, Mike Mueri, Sereina Riniker, Helma Wennemers
Summary: The presence of pendant fatty acids has been found to increase the stability and folding rate of collagen triple helices by interacting with the grooves and creating a molten globule-like intermediate. This interaction accelerates the folding and unfolding process, leading to hyperstability in collagen triple helices.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Food Science & Technology
Xindong Xu, Yuxue Pan, Xiaoying Liu, Zhong Han, Shan Chen
Summary: In this study, selenium nanoparticles (SeNPs) were stabilized with curdlan (CUR) via alkali-neutralization (AN) pretreatment, resulting in enhanced free-radical-scavenging ability and prolonged stability. The stable SeNPs, with an average size of 53.6 +/- 17.7 nm, can be well-stabilized for at least 240 days at 4 degrees C. CUR proves to be an effective food additive for stabilizing SeNPs and improving their bioactivity through triple-helix conformational transition.
Article
Chemistry, Applied
Xindong Xu, Qing Wang, Siya Xue, Yuxue Pan, Shan Chen
Summary: The study found that alkali-neutralization treatment can effectively reduce the size of curdlan's triple-helical aggregates while increasing the relative amount of independent triple helices. The treatment does not alter the primary structure of curdlan chains, but affects the crystalline structure and hydrogen bonding of curdlan.
CARBOHYDRATE POLYMERS
(2021)
Article
Chemistry, Multidisciplinary
Julian L. Kessler, Grace Kang, Zhao Qin, Helen Kang, Frank G. Whitby, Thomas E. Cheatham, Christopher P. Hill, Yang Li, S. Michael Yu
Summary: This study reveals that N-substituted glycines have the potential to stabilize the triple-helix structure, making them valuable for synthesizing collagen-mimetic peptides with unprecedented side chain diversity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Biochemistry & Molecular Biology
Qi Zhang, Xiaojing Li, Kui Huang, Yongjie Huang, Suwen Zhao, Shanshan Liu, Yang Li
Summary: Collagen hybridizing peptides (CHPs) have the ability to target collagen damage in pathological tissues. However, their tendency to self-trimerize hinders their applications. This study provides a solvent-switch method to control the self-assembly of CHP monomers, enabling their utilization in various applications.
Article
Chemistry, Applied
Xue Song, Leilei Si, Xiao Sun, Xiao Zhu, Zhaoxuan Li, Yanyan Li, Yangfan Wang, Hu Hou
Summary: Sea cucumber collagen exhibits shear-thinning and pseudo-plastic properties during thermal processing, and its viscosity and viscoelastic crossover frequency decrease gradually with increasing temperature. The results suggest that the triple helix structure of sea cucumber collagen disappears with temperature rise, and shearing accelerates this change.
Article
Chemistry, Multidisciplinary
Leo D. M. Nicholls, Helma Wennemers
Summary: A peptide catalyst and a gold catalyst were combined for enantioselective addition reactions between branched aldehydes and allenamides, producing gamma,delta-enamide aldehydes with a fully substituted, benzylic stereogenic center. The reaction tolerated a variety of alkyl and alkoxy substituted aldehydes and the products could be elaborated into chiral building blocks. Mechanistic studies highlighted the importance of conformational features of the peptide and a balance of acid/base additives for achieving the desired product.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Greta Vastakaite, Claudio E. Grunenfelder, Helma Wennemers
Summary: This study presents a tripeptide catalyst for the efficient and stereoselective synthesis of chiral succinimides via conjugate addition reactions between aldehydes and C-substituted maleimides. The catalyst exhibits high chemoselectivity and allows direct derivatization of the succinimides to access other chiral compounds.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Applied
Jasper S. Moehler, Lena K. Beiersdoerfer, Brenno Masina, Philipp Wechsler, Helma Wennemers
Summary: N-heterocyclic moieties are commonly found in pharmaceuticals and agrochemicals, but pose a challenge for metalorganic and organocatalytic transformations. This study presents tripeptide catalysts for stereoselective conjugate addition reactions between N-heterocyclic substituted aldehydes and electrophiles, achieving high yields and selectivities.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Tomas Fiala, Emilia P. Barros, Marc-Olivier Ebert, Enrico Ruijsenaars, Sereina Riniker, Helma Wennemers
Summary: This study reveals the significant impact of terminal residues on the stability of collagen model peptides (CMPs). By combining various experimental and simulation techniques, the researchers demonstrate how peptide termini preorganize into a polyproline-II helical structure and affect the stability of triple helices. These findings have important implications for designing peptide mimics of structural proteins and provide a straightforward method to tune the stability of CMPs for various applications.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Tomas Fiala, Emilia P. Barros, Rahel Heeb, Sereina Riniker, Helma Wennemers
Summary: This study elucidates the impact of frame, terminal functional group, and charge on the stability of collagen triple helices, and proposes a method for predicting the melting temperatures of CMP trimers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Rebecca J. B. Schaefer, Kayla Wilson, Maurice Biedermann, Bradley S. Moore, Simon Sieber, Helma Wennemers
Summary: This study successfully detected and isolated microgram quantities of isonitrile compounds using the isonitrile-chlorooxime ligation system and a reactivity-based screening protocol.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Bartosz Lewandowski, Rebecca J. B. Schafer, Etienne Cotter, Dora Harangozo, Helma Wennemers
Summary: Templated synthesis is a fascinating strategy for controlling the length of oligomer synthesis. Traditionally, this requires stoichiometric amounts of the template. However, this article presents an innovative approach using catalytic macrocyclic templates that achieve remarkable length control. The authors also discuss their efforts in developing linear templates for catalytic length-controlled oligomer synthesis.
FARADAY DISCUSSIONS
(2023)
Article
Biochemistry & Molecular Biology
Tobias Schnitzer, Nils Trapp, Lisa-Marie Fischer, Helma Wennemers
Summary: Crystal structures of N-acetylated proline and its analogs with four- and six-membered rings were compared, showing distinct conformational differences that contribute to the zigzag lattice structure.
JOURNAL OF PEPTIDE SCIENCE
(2023)
Article
Chemistry, Organic
Rudiger Bormann, Dominik Zetschok, Helma Wennemers
Summary: Chlorinated malonic acid half thioesters were used as surrogates for chloroacetates in organocatalyzed decarboxylative aldol-type additions, leading to enantioenriched alpha-chloro-beta-hydroxy thioesters. The obtained compounds could be further derivatized, as demonstrated in the synthesis of (+)-prebalamide and (+)-norbalasubramide analogs.
Article
Chemistry, Multidisciplinary
Alena Budinska, Helma Wennemers
Summary: This article presents a mild and efficient organocatalytic method for the stereoselective synthesis of chiral triflones using alpha-aryl vinyl triflones, previously unexplored in asymmetric synthesis. The products can be easily derivatized into disubstituted delta-sultones, gamma-lactones, and pyrrolidine heterocycles, highlighting their synthetic versatility.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Biochemistry & Molecular Biology
Tomas Fiala, Rahel Heeb, Luca Vigliotti, Helma Wennemers
Summary: N-terminal acylation is commonly used to install functional moieties on collagen model peptides. The length of short acyl capping groups has different effects on the thermal stability of collagen triple helices in different frames. This study provides a basis for designing N-terminally functionalized CMPs with predictable effects on triple helix stability.
Article
Chemistry, Multidisciplinary
Giuseppe Antoniazzi, Rebecca J. B. Schafer, Maurice Biedermann, Eric Ruttimann, Helma Wennemers
Summary: This study introduces (4S)- and (4R)-isonitrileproline as building blocks for solid-phase peptide synthesis and investigates the stereoelectronic effect of isonitrile group. The results demonstrate the potential value of Inp in peptide derivatization.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Sonia Vela-Gallego, Bartosz Lewandowski, Jasper Moehler, Alonso Puente, David Gil-Cantero, Helma Wennemers, Andres de la Escosura
Summary: This study investigates the control and tuning of properties of biohybrid catalysts through self-assembly. By combining catalytic tripeptide, fatty acid, and nucleobase derivatives, the biohybrid catalysts form fibrillar structures and catalyze specific reactions in aqueous media. The interactions between nucleobases enhance the ordering of supramolecular structures and affect the catalytic activity and selectivity.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Athanasios Markos, Maurice Biedermann, Johannes Heimgartner, Adeline Schmitt, Kathrin Lang, Helma Wennemers
Summary: In this study, C,N-cyclic-N'-acyl azomethine imines (AMIs) were introduced to bioorthogonal reactions in an aqueous environment, showing stability under physiological conditions and selective reactivity with isonitriles. The AMI-isonitrile ligation demonstrated biocompatibility and orthogonality to commonly used bioorthogonal reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Tobias Schnitzer, Jonas W. Rackl, Helma Wennemers
Summary: This study investigated the properties of tripeptide catalysts in complex mixtures and achieved high reactivity and stereoselectivity by tailoring the conformation of tripeptides. The tripeptide catalysts exhibited remarkable chemoselectivity, even catalyzing reactions in cell lysates.