title: Crystallographic characterization of the ribosomal binding site and molecular mechanism of action of Hygromycin A.
abstract: Hygromycin A (HygA) binds to the large ribosomal subunit and inhibits its peptidyl transferase (PT) activity. The presented structural and biochemical data indicate that HygA does not interfere with the initial binding of aminoacyl-tRNA to the A site, but prevents its subsequent adjustment such that it fails to act as a substrate in the PT reaction. Structurally we demonstrate that HygA binds within the peptidyl transferase center (PTC) and induces a unique conformation. Specifically in its ribosomal binding site HygA would overlap and clash with aminoacyl-A76 ribose moiety and, therefore, its primary mode of action involves sterically restricting access of the incoming aminoacyl-tRNA to the PTC.
authors.affiliation: Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain.
authors.forename: Tatsuya
authors.identifier: http://orcid.org/0000-0001-5056-1074
authors.initials: T
authors.lastname: Kaminishi
authors.affiliation: Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schedlbauer
authors.affiliation: Laboratory of Genetics, Department of Biosciences and Veterinary Medicine, University of Camerino, 62032 Camerino, Italy.
authors.forename: Attilio
authors.initials: A
authors.lastname: Fabbretti
authors.affiliation: Laboratory of Genetics, Department of Biosciences and Veterinary Medicine, University of Camerino, 62032 Camerino, Italy.
authors.forename: Letizia
authors.initials: L
authors.lastname: Brandi
authors.affiliation: Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain.
authors.forename: Borja
authors.initials: B
authors.lastname: Ochoa-Lizarralde
authors.affiliation: Laboratory of Genetics, Department of Biosciences and Veterinary Medicine, University of Camerino, 62032 Camerino, Italy.
authors.forename: Cheng-Guang
authors.initials: CG
authors.lastname: He
authors.affiliation: School of Medicine, Faculty of Health Sciences, Universidad Peruana de Ciencias Aplicadas - UPC, Lima, L-33, Perú
authors.forename: Pohl
authors.initials: P
authors.lastname: Milón
authors.affiliation: Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain sean.connell@gmail.com.
authors.forename: Sean R
authors.identifier: http://orcid.org/0000-0001-7807-7049
authors.initials: SR
authors.lastname: Connell
authors.affiliation: Laboratory of Genetics, Department of Biosciences and Veterinary Medicine, University of Camerino, 62032 Camerino, Italy claudio.gualerzi@unicam.it.
authors.forename: Claudio O
authors.initials: CO
authors.lastname: Gualerzi
authors.affiliation: Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain pfucini@gmail.com.
authors.forename: Paola
authors.identifier: http://orcid.org/0000-0003-1724-8507
authors.initials: P
authors.lastname: Fucini
mesh_terms: D001665:Binding Sites; D002934:Cinnamates / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D006921:Hygromycin B / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D008958:Models, Molecular; D010458:Peptidyl Transferases / Q000737:chemistry / Q000187:drug effects; D011500:Protein Synthesis Inhibitors / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism; D054681:Ribosome Subunits, Large, Bacterial / Q000737:chemistry* / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism
chemical_list: D002934:Cinnamates; D011500:Protein Synthesis Inhibitors; D012346:RNA, Transfer, Amino Acyl; D006921:Hygromycin B; C026273:hygromycin A; D010458:Peptidyl Transferases