title: Characterization of a high-affinity sialic acid-specific CBM40 from Clostridium perfringens and engineering of a divalent form.
abstract: CBMs (carbohydrate-binding modules) are a class of polypeptides usually associated with carbohydrate-active enzymatic sites. We have characterized a new member of the CBM40 family, coded from a section of the gene NanI from Clostridium perfringens Glycan arrays revealed its preference towards α(2,3)-linked sialosides, which was confirmed and quantified by calorimetric studies. The CBM40 binds to α(2,3)-sialyl-lactose with a Kd of ∼30 μM, the highest affinity value for this class of proteins. Inspired by lectins' structure and their arrangement as multimeric proteins, we have engineered a dimeric form of the CBM, and using SPR (surface plasmon resonance) we have observed 6-11-fold binding increases due to the avidity affect. The structures of the CBM, resolved by X-ray crystallography, in complex with α(2,3)- or α(2,6)-sialyl-lactose explain its binding specificity and unusually strong binding.
authors.affiliation: Biomedical Chemistry Institute, New York University Department of Chemistry, 100 Washington Square East, Room 1001, New York, NY 10003, U.S.A. CERMAV, UPR5301, CNRS and Université Grenoble Alpes, 601 rue de la Chimie, BP 53, 38041, Grenoble, France.
authors.forename: João P
authors.initials: JP
authors.lastname: Ribeiro
authors.affiliation: Biomedical Chemistry Institute, New York University Department of Chemistry, 100 Washington Square East, Room 1001, New York, NY 10003, U.S.A.
authors.forename: William
authors.initials: W
authors.lastname: Pau
authors.affiliation: Université Grenoble Alpes, DCM, BP 53, 38041 Grenoble cedex 9, France.
authors.forename: Carlo
authors.initials: C
authors.lastname: Pifferi
authors.affiliation: Université Grenoble Alpes, DCM, BP 53, 38041 Grenoble cedex 9, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Renaudet
authors.affiliation: CERMAV, UPR5301, CNRS and Université Grenoble Alpes, 601 rue de la Chimie, BP 53, 38041, Grenoble, France.
authors.forename: Annabelle
authors.initials: A
authors.lastname: Varrot
authors.affiliation: Biomedical Chemistry Institute, New York University Department of Chemistry, 100 Washington Square East, Room 1001, New York, NY 10003, U.S.A. lkmahal@nyu.edu imberty@cermav.cnrs.fr.
authors.forename: Lara K
authors.initials: LK
authors.lastname: Mahal
authors.affiliation: CERMAV, UPR5301, CNRS and Université Grenoble Alpes, 601 rue de la Chimie, BP 53, 38041, Grenoble, France lkmahal@nyu.edu imberty@cermav.cnrs.fr.
authors.forename: Anne
authors.initials: A
authors.lastname: Imberty
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001665:Binding Sites; D020134:Catalytic Domain; D003016:Clostridium perfringens / Q000378:metabolism*; D018360:Crystallography, X-Ray; D007700:Kinetics; D007785:Lactose / Q000031:analogs & derivatives / Q000378:metabolism; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism*; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000378:metabolism*; D012794:Sialic Acids / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D010455:Peptides; D011134:Polysaccharides; D011956:Receptors, Cell Surface; D012794:Sialic Acids; C055213:saccharide-binding proteins; C000020:N-acetylneuraminoyllactose; D019158:N-Acetylneuraminic Acid; D007785:Lactose
keywords: Clostridium perfringens; X-ray structure; carbohydrate-binding domain; protein–glycan interactions; sialic acid