BEGIN:VCALENDAR VERSION:2.0 PRODID:-//wp-events-plugin.com//7.2.2.1//EN TZID:Asia/Jerusalem X-WR-TIMEZONE:Asia/Jerusalem BEGIN:VEVENT UID:1178@biology.technion.ac.il DTSTART;TZID=Asia/Jerusalem:20230605T130000 DTEND;TZID=Asia/Jerusalem:20230605T140000 DTSTAMP:20230524T093309Z URL:https://biology.technion.ac.il/en/seminars/faculty-seminar-associate-p rof-meytal-landau-virulent-and-antimicrobial-amyloids-in-infections-and-ne urodegeneration/ SUMMARY:Faculty Seminar- Associate Prof. Meytal Landau-Virulent and Antimic robial Amyloids in Infections and Neurodegeneration [No Categories] DESCRIPTION:Location: Faculty Of Biology Auditorium Associate Prof. Meytal Landau\n Affiliation: \n Host:Dr. Levy Sagi\n Virulent and Antimicrobial Amyloids in Infections and Neurodegeneration\n\n \;\n\nMeytal Landau\n \n \;\n\nAmyloids are protein fibers with robust structures\, which ar e known mainly in the context of neurodegenerative diseases yet are secret ed by species across kingdoms of life to carry out physiological function and help survival and activity. For example\, several microbial amyloids s erve as key “weapons” making infections more aggressive. Thereby\, the y exposed new routes for the development of novel antivirulence drugs\, wh ich may elicit less resistance as the evolutionary pressure on the microbe is less profound compared to bactericidal drugs. Our laboratory published the first structures of bacterial amyloid fibrils involved in virulent ac tivities. Our findings thus far exposed an extreme structural diversity\, extending beyond canonical amyloid cross-β structures\, and encoding diff erent activities. In particular\, the discovery of a novel class of cross- α amyloid fibrils of toxic peptides presented a unique protein architectu re\, offered drug targets and leads\, and opened a fresh perspective to st udy amyloid-related toxicity. Moreover\, we revealed that amyloids secrete d by bacteria highly abundant in the microbiome and food sources show simi larities in molecular structures to human amyloids involved in neurodegene rative diseases such as Alzheimer’s and Parkinson’s. This might raise concerns about the involvement of microbes in facilitating these diseases\ , similar to prion proteins transmitted by contaminated meat that elicit t he Creutzfeldt-Jakob disease.  In addition\, we identified peptides produ ced across species that provide antimicrobial protection that form amyloid fibrils and determined their first high resolution structures. This amylo id-antimicrobial link signifies a physiological role in neuroimmunity for human amyloids. Such antimicrobial fibrils can facilitate the design of fu nctional and stable nanostructures to serve as a stable coating for medica l devices or implants\, industrial equipment\, food packing and more.\n\nA tomic structures of amyloid fibrils determined by X-ray crystallography an d cryogenic electron microscopy (cryo-EM) of microbial and antimicrobial a myloids. A scanning electron micrograph shows cells damaged by a cytotoxic bacterial amyloid peptide\, and transmission electron micrographs display fibrils of antimicrobial peptides covering bacterial cells\, and of massi ve fibrils formed by biofilm-associated amyloids.\n\n \n\nReferences\n\n Tayeb-Fligelman\, O. Tabachnikov\, A. Moshe\, O. Goldshmidt-Tran\, M.R. S awaya\, N. Coquelle\, J-P. Colletier\, and M. Landau. Science 355(6327): 8 31-833\; 2017\n Salinas\, A. Moshe\, J-P. Colletier\, and M. Landau. Nat. Commun. 9(1):3512\; 2018.\n Perov\, O. Lidor\, N. Salinas\, N. Golan\, E . Tayeb-Fligelman\, M. Deshmukh\, D. Willbold\, and M. Landau. PLoS Pathog 15(8): e1007978\; 2019\n Tayeb-Fligelman\, N. Salinas\, O. Tabachnikov\, and M. Landau. Structure S0969-2126(19)30445-9\; 2020\n Engelberg and M. Landau. Nat. Commun. 11\, 3894\; 2020\n Salinas\, E. Tayeb-Fligelman\, M . Sammito\, D. Bloch\, R. Jelinek\, D. Noy\, I. Uson\, and M. Landau. PNAS 118 (3) e2014442118\; 2021\n Engelberg\, P. Ragonis-Bachar and M. Landau .    Biomacromolecules2022\n Bücker\, C. Seuring\, C. Cazey\, K. Vei th\, M. García-Alai\, K. Grünewald\, and M. Landau. The Cryo-EM Structu res of two Amphibian Antimicrobial Cross-β Amyloid Fibrils.  Nat. Commu n 13: 4356\; 2022\n Ragonis-Bachar*\, B. Rayan*\, E. Barnea\, Y.Engelberg \, A. Upcher\, M. Landau. Natural Antimicrobial Peptides Self-assemble as alpha/beta Chameleon Amyloids. ACS Biomacromolecules 12\;23(9):3713-3727 2 022\n LOCATION:Faculty Of Biology Auditorium END:VEVENT BEGIN:VTIMEZONE TZID:Asia/Jerusalem X-LIC-LOCATION:Asia/Jerusalem BEGIN:DAYLIGHT DTSTART:20230324T030000 TZOFFSETFROM:+0200 TZOFFSETTO:+0300 TZNAME:IDT END:DAYLIGHT END:VTIMEZONE END:VCALENDAR