title: Affinity Crystallography: A New Approach to Extracting High-Affinity Enzyme Inhibitors from Natural Extracts.
abstract: Natural products are an important source of novel drug scaffolds. The highly variable and unpredictable timelines associated with isolating novel compounds and elucidating their structures have led to the demise of exploring natural product extract libraries in drug discovery programs. Here we introduce affinity crystallography as a new methodology that significantly shortens the time of the hit to active structure cycle in bioactive natural product discovery research. This affinity crystallography approach is illustrated by using semipure fractions of an actinomycetes culture extract to isolate and identify a cathepsin K inhibitor and to compare the outcome with the traditional assay-guided purification/structural analysis approach. The traditional approach resulted in the identification of the known inhibitor antipain (1) and its new but lower potency dehydration product 2, while the affinity crystallography approach led to the identification of a new high-affinity inhibitor named lichostatinal (3). The structure and potency of lichostatinal (3) was verified by total synthesis and kinetic characterization. To the best of our knowledge, this is the first example of isolating and characterizing a potent enzyme inhibitor from a partially purified crude natural product extract using a protein crystallographic approach.
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Adeleke H
authors: AH
authors: Aguda
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Vincent
authors: V
authors: Lavallee
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Ping
authors: P
authors: Cheng
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Tina M
authors: TM
authors: Bott
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Labros G
authors: LG
authors: Meimetis
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Simon
authors: S
authors: Law
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Nham T
authors: NT
authors: Nguyen
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: David E
authors: DE
authors: Williams
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Jadwiga
authors: J
authors: Kaleta
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Ivan
authors: I
authors: Villanueva
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Julian
authors: J
authors: Davies
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Raymond J
authors: RJ
authors: Andersen
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Gary D
authors: GD
authors: Brayer
authors: Department of Oral Biological and Medical Sciences, Faculty of Dentistry, ‡Department of Biochemistry and Molecular Biology, Faculty of Medicine, §Department of Chemistry and Earth, Ocean & Atmospheric Sciences, Faculty of Science, ⊥Department of Microbiology, Faculty of Science, and ∥Centre for Blood Research, University of British Columbia , Vancouver, BC Canada , V6T 1Z3.
authors: Dieter
authors: D
authors: Brömme
mesh_terms: D000976:Antipain / Q000737:chemistry / Q000494:pharmacology; D001688:Biological Products / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001955:British Columbia; D056657:Cathepsin K / Q000037:antagonists & inhibitors*; D018360:Crystallography, X-Ray; D008011:Lichens / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D001688:Biological Products; D010455:Peptides; C000617680:lichostatinal; D000976:Antipain; D056657:Cathepsin K