title: Crystal Structure of the Zorbamycin-Binding Protein ZbmA, the Primary Self-Resistance Element in Streptomyces flavoviridis ATCC21892.
abstract: The bleomycins (BLMs), tallysomycins (TLMs), phleomycin, and zorbamycin (ZBM) are members of the BLM family of glycopeptide-derived antitumor antibiotics. The BLM-producing Streptomyces verticillus ATCC15003 and the TLM-producing Streptoalloteichus hindustanus E465-94 ATCC31158 both possess at least two self-resistance elements, an N-acetyltransferase and a binding protein. The N-acetyltransferase provides resistance by disrupting the metal-binding domain of the antibiotic that is required for activity, while the binding protein confers resistance by sequestering the metal-bound antibiotic and preventing drug activation via molecular oxygen. We recently established that the ZBM producer, Streptomyces flavoviridis ATCC21892, lacks the N-acetyltransferase resistance gene and that the ZBM-binding protein, ZbmA, is sufficient to confer resistance in the producing strain. To investigate the resistance mechanism attributed to ZbmA, we determined the crystal structures of apo and Cu(II)-ZBM-bound ZbmA at high resolutions of 1.90 and 1.65 Å, respectively. A comparison and contrast with other structurally characterized members of the BLM-binding protein family revealed key differences in the protein-ligand binding environment that fine-tunes the ability of ZbmA to sequester metal-bound ZBM and supports drug sequestration as the primary resistance mechanism in the producing organisms of the BLM family of antitumor antibiotics.
authors.affiliation: Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Rudolf
authors.affiliation: Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Lance
authors.initials: L
authors.lastname: Bigelow
authors.affiliation: Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Changsoo
authors.initials: C
authors.lastname: Chang
authors.affiliation: Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Marianne E
authors.initials: ME
authors.lastname: Cuff
authors.affiliation: Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States.
authors.forename: Jeremy R
authors.initials: JR
authors.lastname: Lohman
authors.affiliation: Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States.
authors.forename: Chin-Yuan
authors.initials: CY
authors.lastname: Chang
authors.affiliation: Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States.
authors.forename: Ming
authors.initials: M
authors.lastname: Ma
authors.affiliation: Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States.
authors.forename: Dong
authors.initials: D
authors.lastname: Yang
authors.affiliation: Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Shonda
authors.initials: S
authors.lastname: Clancy
authors.affiliation: Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Gyorgy
authors.initials: G
authors.lastname: Babnigg
authors.affiliation: Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Joachimiak
authors.affiliation: BioSciences at Rice and Department of Chemistry, Rice University , Houston, Texas 77251, United States.
authors.forename: George N
authors.initials: GN
authors.lastname: Phillips
authors.affiliation: Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States.|Department of Molecular Therapeutics, The Scripps Research Institute , Jupiter, Florida 33458, United States.|Natural Products Library Initiative, The Scripps Research Institute , Jupiter, Florida 33458, United States.
authors.forename: Ben
authors.initials: B
authors.lastname: Shen
mesh_terms: D000595:Amino Acid Sequence; D000903:Antibiotics, Antineoplastic / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D002236:Carbohydrate Conformation; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D017124:Conserved Sequence; D003460:Crystallization; D018360:Crystallography, X-Ray; D004352:Drug Resistance, Microbial / Q000235:genetics / Q000502:physiology*; D005798:Genes, Bacterial; D006020:Glycopeptides / Q000378:metabolism / Q000494:pharmacology; D008024:Ligands; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011487:Protein Conformation; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013302:Streptomyces / Q000737:chemistry* / Q000235:genetics; D013329:Structure-Activity Relationship
chemical_list: D000903:Antibiotics, Antineoplastic; D001426:Bacterial Proteins; D002352:Carrier Proteins; D006020:Glycopeptides; D008024:Ligands; C003787:zorbamycin