报告题目：Dynamic and Functional Nanoarchitectures from DNA Amphiphiles and Supercharged Polypeptides
报 告 人：Andreas Herrmann教授
DNA is a superb material for the fabrication of nanostructures. Defined objects can be achieved by folding DNA in the desired shape, by attaching it to inorganic particles or by generating DNA amphiphiles that self-assemble into nanostructures driven by microphase separation. Single-stranded, soft matter DNA nanoparticles from the latter class of materials can be efficiently functionalized by hybridization. When equipped with targeting units by Watson-Crick base pairing and incorporation of a hydrophobic drug into the interior, they kill cancer cells in vitro. Similarly, they were loaded with antibiotics by hybridizing them with drug-binding aptamers. These DNA based carriers adhere strongly to the ocular surface and were successfully employed for ophthalmic drug delivery in vivo. Beside micelle systems, our group incorporated DNA amphiphiles into the phospholipid bilayer of vesicles. DNA specific aggregation and payload release from these nanocontainers were demonstrated. In addition to potential therapeutic use, DNA amphiphiles were utilized as probes in Si-nanowire field effect transistors and when oligonucleotides are complexed with cationic surfactants they form the first thermotropic biomacromolecular liquid crystals.
While nucleic acids are intrinsically negatively charged, introduction of several charges in proteins requires genetic engineering. Our group developed supercharged polypeptides (SUPs) that are based on the elastin motif (VPGXG)n with X being glutamic acid or lysine resulting in unfolded proteinpoyelectrolytes with high charge density. Like DNA, they form thermotropic liquid crystals when complexed with surfactants. When SUPs are combined with RNA they form coacervates, which adopt self-dividing fibrils once they are introduced into the dissipative environment of tubulin-like structures. When positive SUPs interact with saliva conditioning films they stabilize mucin architectures to potentially improve biolubrication in patients with Sjögren’s syndrome. Moreover, they were fused with fluorescent proteins allowing to fabricate sensor arrays. With such fluorescent scaffolds it was possible to classify a large number of whiskeys according to age, blending status and origin.
Andreas Herrmann studied chemistry at the University of Mainz in Germany. From 1997 to 2000 he pursued his graduate studies at the Max Planck Institute for Polymer Research in the group of Professor K. Müllen. Then he worked as a consultant for Roland Berger Management Consultants in Munich (2001). In the years 2002 and 2003 he returned to academia working on protein engineering at the Swiss Federal Institute of Technology in Zurich with Professor D. Hilvert. In 2004 he was appointed as a head of a junior research group at the Max Planck Institute for Polymer Research dealing with biological-organic and biological-polymeric hybrid materials. From 2007 to 2017, he was a professor and Head of the Board at the Zernike Institute for Advanced Materials at the University of Groningen in the Netherlands, and Program director at the University Medical Center Groningen (UMCG). Since 2017 Prof. Herrmann is Head of Chemistry at RWTH Aachen University and Scientific Board Member of the DWI Leibniz Institute for Interactive Materials at Aachen and Chair Professor of Macromolecular Materials and Systems. He has published more than 140 papers in high ranked journals, including Nature Chem. (1), Nature Nanotech. (1), Nature Commun. (3), PNAS (1), Angew. Chem. (17), JACS (13), Adv. Mat. (10), Phys. Rev. Lett. (2). Prof Herrmann has been authorized more than 10 patents, and has started up a high-tech company, Agilebiotics, which devotes to antibiotic development. Moreover, Prof. Herrman has been awarded many big grants, including ERC Advanced/Starting Grants, NOW-VICI grant. He is the Coordinator for MSCA Cofund Grant, Winner of the Eyenovative Prize from Novartis, Dr. Hermann-Schnell-Prize, and Reimund-Stadler-Prize from the German Chemical Society (GDCh).