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Buchko, Garry W

Publications and source records attributed to Buchko, Garry W.

Enzyme Design From the Bottom Up: An Active Nickel Electrocatalyst with a Structured Peptide Outer Coordination Sphere

Functional, peptide-containing metal complexes with a well-defined peptide structure have the potential to enhance molecular catalysts via an enzyme-like outer coordination sphere. Here, we report the synthesis and characterization of an active, peptide-based metal complex built upon the well characterized hydrogen production catalyst, Ni(PPh2NPh)2. The incorporated peptide maintains its B-hairpin structure when appended to the metal core, and the electrocatalytic activity of the peptide-based metal complex (~100,000 s-1) is fully retained. The combination of an active molecular catalyst with a structured peptide outer coordination sphere provides a scaffold that permits the incorporation of features of an enzyme-like outer-coordination sphere necessary to create molecular electrocatalysts with en-hanced functionality.

bioinspired↗

Behind Every Good Metabolite there is a Great Enzyme (and perhaps a structure)

Today, due to great technological advancements, it is possible to study everything at the same time. This ability has given birth to “totality” studies in the fields of genomics, transcriptomics, proteomics, and metabolomics. In turn, the combined study of all these global analyses gave birth to the field of systems biology. Another “totality” field brought to life with new emerging technologies is structural genomics, an effort to determine the three-dimensional structure of every protein encoded in a genome. The Seattle Structural Genomics Center for Infectious Disease (SSGCID) is a specialized structural genomics effort composed of academic (University of Washington), government (Pacific Northwest National Laboratory), not-for-profit (Seattle BioMed), and commercial (Emerald BioStructures) institutions that is funded by the National Institute of Allergy and Infectious Diseases (Federal Contract: HHSN272200700057C and HHSN27220120025C) to apply genome-scale approaches in solving protein structures from biodefense organisms, as well as those causing emerging and re-emerging disease. In five years over 540 structures have been deposited into the Protein Data Bank (PDB) by SSGICD. About one third of all SSGCID structures contain bound ligands, many of which are metabolites or metabolite analogues present in the cell. These proteins structures are the blueprints for the structure-based design of the next generation of drugs against bacterial pathogens and other infectious diseases. Many of the selected SSGCID targets are annotated enzymes from known metabolomic pathways essential to cellular vitality since selectively “knocking-out” one of the enzymes in an important pathway with a drug may be fatal to the organism. One reason metabolomic pathways are important is because of the small molecules, or metabolites, produced at various steps in these pathways and identified by metabolomic studies. Unlike genomics, transcriptomics, and proteomics that may be influenced by epigenetic, post-transcriptional, and post-translational modifications, respectively, the metabolites present in the cell at any one time represent downstream biochemical endproducts, and therefore, metabolite profiles may be most closely associated with a phenotype and provide valuable information for infectious disease research. Metabolomic data would be even more useful if it could be linked to the vast amount of structural genomics data. Towards this goal SSGCID has created an automated website (http://apps.sbri.org/SSGCIDTargetStatus/Pathway) that assigns selected SSGCID target proteins to MetaCyc pathways (http://metacyc.org/). Details of this website will be provided here. The SSGCID-Pathway website represents a first big step towards linking metabolites and metabolic pathways to structural genomic data with the goal of accelerating the discovery of new agents to battle infectious diseases.

Environmental Molecular Sciences Laboratory↗

Active Hydrogenation Catalyst with a Structured, Peptide-Based Outer-Coordination Sphere

The synthesis, catalytic activity, and structural features of a rhodium-based hydrogenation catalyst containing a phosphine ligand coupled to a 14-residue peptide are reported. Both CD and NMR spectroscopy show that the peptide adopts a helical structure in 1:1:1 TFE/MeCN/H2O that is maintained when the peptide is attached to the ligand and when the ligand is attached to the metal complex. The metal complex hydrogenates aqueous solutions of 3-butenol to 1-butanol at 360 ± 50 turnovers/Rh/h at 294 K. This peptide- based catalyst represents a starting point for developing and characterizing a peptide-based outer-coordination sphere that can be used to introduce enzyme-like features into molecular catalysts. This work was funded by the US DOE Basic Energy Sciences, Chemical Sciences, Geoscience and Biosciences Division (AJ, JCL and WJS), the Office of Science Early Career Research Program through the Office of Basic Energy Sciences (GWB, MLR and WJS). Part of the research was conducted at the W.R. Wiley Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by U.S. Department of Energy’s Office of Biolog-ical and Environmental Research (BER) program located at Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle for the U.S. Department of Energy.

amino acid catalysts↗