Cargando…

New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine

The homodimeric β-lactoglobulin belongs to the lipocalin family of proteins that transport a wide range of hydrophobic molecules and can be modified by mutagenesis to develop specificity for novel groups of ligands. In this work, new lactoglobulin variants, FAF (I56F/L39A/M107F) and FAW (I56F/L39A/M...

Descripción completa

Detalles Bibliográficos
Autores principales: Loch, Joanna I., Barciszewski, Jakub, Śliwiak, Joanna, Bonarek, Piotr, Wróbel, Paulina, Pokrywka, Kinga, Shabalin, Ivan G., Minor, Wladek, Jaskolski, Mariusz, Lewiński, Krzysztof
Formato: Online Artículo Texto
Lenguaje:English
Publicado: International Union of Crystallography 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9067113/
https://www.ncbi.nlm.nih.gov/pubmed/35546795
http://dx.doi.org/10.1107/S2052252522004183
_version_ 1784699935939100672
author Loch, Joanna I.
Barciszewski, Jakub
Śliwiak, Joanna
Bonarek, Piotr
Wróbel, Paulina
Pokrywka, Kinga
Shabalin, Ivan G.
Minor, Wladek
Jaskolski, Mariusz
Lewiński, Krzysztof
author_facet Loch, Joanna I.
Barciszewski, Jakub
Śliwiak, Joanna
Bonarek, Piotr
Wróbel, Paulina
Pokrywka, Kinga
Shabalin, Ivan G.
Minor, Wladek
Jaskolski, Mariusz
Lewiński, Krzysztof
author_sort Loch, Joanna I.
collection PubMed
description The homodimeric β-lactoglobulin belongs to the lipocalin family of proteins that transport a wide range of hydrophobic molecules and can be modified by mutagenesis to develop specificity for novel groups of ligands. In this work, new lactoglobulin variants, FAF (I56F/L39A/M107F) and FAW (I56F/L39A/M107W), were produced and their interactions with the tricyclic drug desipramine (DSM) were studied using X-ray crystallography, calorimetry (ITC) and circular dichroism (CD). The ITC and CD data showed micromolar affinity of the mutants for DSM and interactions according to the classical one-site binding model. However, the crystal structures unambiguously showed that the FAF and FAW dimers are capable of binding DSM not only inside the β-barrel as expected, but also at the dimer interface and at the entrance to the binding pocket. The presented high-resolution crystal structures therefore provide important evidence of the existence of alternative ligand-binding sites in the β-lactoglobulin molecule. Analysis of the crystal structures highlighted the importance of shape complementarity for ligand recognition and selectivity. The binding sites identified in the crystal structures of the FAF–DSM and FAW–DSM complexes together with data from the existing literature are used to establish a systematic classification of the ligand-binding sites in the β-lactoglobulin molecule.
format Online
Article
Text
id pubmed-9067113
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher International Union of Crystallography
record_format MEDLINE/PubMed
spelling pubmed-90671132022-05-10 New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine Loch, Joanna I. Barciszewski, Jakub Śliwiak, Joanna Bonarek, Piotr Wróbel, Paulina Pokrywka, Kinga Shabalin, Ivan G. Minor, Wladek Jaskolski, Mariusz Lewiński, Krzysztof IUCrJ Research Papers The homodimeric β-lactoglobulin belongs to the lipocalin family of proteins that transport a wide range of hydrophobic molecules and can be modified by mutagenesis to develop specificity for novel groups of ligands. In this work, new lactoglobulin variants, FAF (I56F/L39A/M107F) and FAW (I56F/L39A/M107W), were produced and their interactions with the tricyclic drug desipramine (DSM) were studied using X-ray crystallography, calorimetry (ITC) and circular dichroism (CD). The ITC and CD data showed micromolar affinity of the mutants for DSM and interactions according to the classical one-site binding model. However, the crystal structures unambiguously showed that the FAF and FAW dimers are capable of binding DSM not only inside the β-barrel as expected, but also at the dimer interface and at the entrance to the binding pocket. The presented high-resolution crystal structures therefore provide important evidence of the existence of alternative ligand-binding sites in the β-lactoglobulin molecule. Analysis of the crystal structures highlighted the importance of shape complementarity for ligand recognition and selectivity. The binding sites identified in the crystal structures of the FAF–DSM and FAW–DSM complexes together with data from the existing literature are used to establish a systematic classification of the ligand-binding sites in the β-lactoglobulin molecule. International Union of Crystallography 2022-04-29 /pmc/articles/PMC9067113/ /pubmed/35546795 http://dx.doi.org/10.1107/S2052252522004183 Text en © Joanna I. Loch et al. 2022 https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
spellingShingle Research Papers
Loch, Joanna I.
Barciszewski, Jakub
Śliwiak, Joanna
Bonarek, Piotr
Wróbel, Paulina
Pokrywka, Kinga
Shabalin, Ivan G.
Minor, Wladek
Jaskolski, Mariusz
Lewiński, Krzysztof
New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine
title New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine
title_full New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine
title_fullStr New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine
title_full_unstemmed New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine
title_short New ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine
title_sort new ligand-binding sites identified in the crystal structures of β-lactoglobulin complexes with desipramine
topic Research Papers
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9067113/
https://www.ncbi.nlm.nih.gov/pubmed/35546795
http://dx.doi.org/10.1107/S2052252522004183
work_keys_str_mv AT lochjoannai newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT barciszewskijakub newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT sliwiakjoanna newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT bonarekpiotr newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT wrobelpaulina newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT pokrywkakinga newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT shabalinivang newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT minorwladek newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT jaskolskimariusz newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine
AT lewinskikrzysztof newligandbindingsitesidentifiedinthecrystalstructuresofblactoglobulincomplexeswithdesipramine