Lipscomb. William

LIPSCOMB. WILLIAM N. l 1919—). An American chemist who won the Nobel prize fur chemistry in 1976 for his studies on ihe structure and bonding mechanisms of borancs. Much ol Hie research concerned structure and function of enzymes and natural products in organic and theoretical chemistry. He studied at (he Universities of Kentucky. California, and Minnesota. 

Figure 2.11 Beta sheets are usuaiiy represented simply by arrows in topology diagrams that show both the direction of each (3 strand and the way the strands are connected to each other along the polypeptide chain. Such topology diagrams are here compared with more elaborate schematic diagrams for different types of (3 sheets, (a) Four strands. Antiparallel (3 sheet in one domain of the enzyme aspartate transcarbamoylase. The structure of this enzyme has been determined to 2.8 A resolution in the laboratory of William Lipscomb, Harvard University, (b) Five strands. Parallel (3 sheet in the redox protein flavodoxin, the structure of which has been determined to 1.8 A resolution in the laboratory of Martha Ludwig, University of Michigan, (c) Eight strands. Antiparallel barrel in the electron carrier plastocyanln. This Is a closed barrel where the sheet is folded such that (3 strands 2 and 8 are adjacent. The structure has been determined to 1.6 A resolution in the laboratory of Hans Freeman in Sydney, Australia. (Adapted from J. Richardson.)...

Carboxypeptidases are zinc-containing enzymes that catalyze the hydrolysis of polypeptides at the C-terminal peptide bond. The bovine enzyme form A is a monomeric protein comprising 307 amino acid residues. The structure was determined in the laboratory of William Lipscomb, Harvard University, in 1970 and later refined to 1.5 A resolution. Biochemical and x-ray studies have shown that the zinc atom is essential for catalysis by binding to the carbonyl oxygen of the substrate. This binding weakens the C =0 bond by... 

The Synchronous-Transit Method for determining Reaction Pathways and Locating Molecular Transition States Thomas A. Halgren and William N. Lipscomb Chemical Physics Letters 49 (1977) 225-232... 

E O Fischer and H. P. Fritz Recent Studies of the Boron Hydrides William A, Lipscomb Lattice Energies and Their Significance in Inorganic Chemistry T C. Waddington... 

William Lipscomb United States structure of borane and bonding... 

William N. Lipscomb Harvard, MA, USA) Ilya Prigogine Brussels, Belgium)... 

Recent Studies of the Boron Hydrides William N. Lipscomb... 

Figure 7-20 (A) Subunit assembly of two C3 catalytic trimers (green) and three R2 regulatory dimers around the periphery in aspartate carbamoyltransferase. After Krause et a/.109 Courtesy of William N. Lipscomb. The aspartate-and carbamoylphosphate-binding domains of the catalytic subunits are labeled Asp and CP, respectivley, while the zinc and allosteric domains of the regulatory subunits are labeled Alio and Zn, respectively. (B) Ribbon drawing of a single pair of regulatory (left) and catalytic (right) subunits with the structural domains labeled. MolScript drawing from Thomas et al.no...

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