title: Identification of inhibitors of the transmembrane protease FlaK of Methanococcus maripaludis.
abstract: GxGD-type intramembrane cleaving proteases (I-CLiPs) form a family of proteolytic enzymes that feature an aspartate-based catalytic mechanism. Yet, they structurally and functionally largely differ from the classical pepsin-like aspartic proteases. Among them are the archaeal enzyme FlaK, processing its substrate FlaB2 during the formation of flagella and γ-secretase, which is centrally involved in the etiology of the neurodegenerative Alzheimer's disease. We developed an optimized activity assay for FlaK and based on screening of a small in-house library and chemical synthesis, we identified compound 9 as the first inhibitor of this enzyme. Our results show that this intramembrane protease differs from classical pepsin-like aspartic proteases and give insights into the substrate recognition of this enzyme. By providing the needed tools to further study the enzymatic cycle of FlaK, our results also enable further studies towards a functional understanding of other GxGD-type I-CLiPs.
authors.affiliation: Leibniz Institute on Aging (FLI), Protein Crystallography Group, Beutenbergstr. 11, Jena, 07745, Germany.
authors.forename: Ina
authors.initials: I
authors.lastname: Coburger
authors.affiliation: Leibniz Institute on Aging (FLI), Protein Crystallography Group, Beutenbergstr. 11, Jena, 07745, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Schaub
authors.affiliation: Leibniz Institute on Aging (FLI), Protein Crystallography Group, Beutenbergstr. 11, Jena, 07745, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Roeser
authors.affiliation: Department of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, Marburg, 35032, Germany.
authors.forename: Kornelia
authors.initials: K
authors.lastname: Hardes
authors.affiliation: Department of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, Marburg, 35032, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Maeder
authors.affiliation: Department of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, Marburg, 35032, Germany.
authors.forename: Nina
authors.initials: N
authors.lastname: Klee
authors.affiliation: Department of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, Marburg, 35032, Germany.
authors.forename: Torsten
authors.initials: T
authors.lastname: Steinmetzer
authors.affiliation: Institute of Pharmacy, Pharmaceutical Chemistry I, University of Bonn, Brühler Str. 7, Bonn, 53119, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: Imhof
authors.affiliation: Department of Pharmaceutical Chemistry, Philipps University Marburg, Marbacher Weg 6, Marburg, 35032, Germany.
authors.forename: Wibke E
authors.initials: WE
authors.lastname: Diederich
authors.affiliation: Leibniz Institute on Aging (FLI), Protein Crystallography Group, Beutenbergstr. 11, Jena, 07745, Germany.
authors.forename: Manuel E
authors.initials: ME
authors.lastname: Than
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism*; D005407:Flagella / Q000378:metabolism; D005408:Flagellin / Q000378:metabolism; D008565:Membrane Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D017017:Methanococcus / Q000201:enzymology*; D011480:Protease Inhibitors / Q000378:metabolism*
chemical_list: D019843:Archaeal Proteins; C489684:FlaB2 protein, archaeal; D008565:Membrane Proteins; D011480:Protease Inhibitors; D005408:Flagellin; D010450:Endopeptidases
keywords: Gel-shift protease assay; I-CLiP; TFPP.; inhibitors; membrane proteins