Evans, Philip

Evans, Philip, and Thomas S. Wurster. Getting Real about Virtual Commerce. Harvard Business Review (November-December 1999) 84—94. 

Figure 16-23 Three-dimensional structure of methylmalonyl-CoA mutase from Propionobacterium. shermanii. The B12 coenzyme is deeply buried, as is the active site. A molecule of bound desulfo-coenzyme A, a substrate analog, blocks the active site entrance on the left side. From Mancia et al.i05 Courtesy of Philip R. Evans.

Philip Evans and his coworkers have determined the crystal structures of phosphofructokinase from two species of bacteria, E. coli and Bacillus stearothermophilus. By crystallizing the enzyme in the presence and absence of the substrate and several allosteric effectors, they obtained detailed views of both the T and R conformations. This work has led to an explanation of why phosphofructokinase appears to be constrained largely to all-or-nothing transitions between these two states, rather than adopting a series of intermediate conformations. 

S. WOODY BASS, CAREY N. BARRY, PHILIP L. ROBINSON, and SLAYTON A. EVANS, JR. 

This enzyme s role in humans is to assist the detoxification of propionate derived from the degradation of the amino acids methionine, threonine, valine, and isoleucine. Propionyl-CoA is carboxylated to (5 )-methylmalonyl-CoA, which is epimerized to the (i )-isomer. Coenzyme Bi2-dependent methylmalonyl-CoA mutase isomerizes the latter to succinyl-CoA (Fig. 2), which enters the Krebs cycle. Methylmalonyl-CoA mutase was the first coenzyme B -dependent enzyme to be characterized crystallographically (by Philip Evans and Peter Leadlay). A mechanism for the catalytic reaction based on ab initio molecular orbital calculations invoked a partial protonation of the oxygen atom of the substrate thioester carbonyl group that facilitated formation of an oxycyclopropyl intermediate, which connects the substrate-derived and product-related radicals (14). The partial protonation was supposed to be provided by the hydrogen bonding of this carbonyl to His 244, which was inferred from the crystal structure of the protein. The ability of the substrate and product radicals to interconvert even in the absence of the enzyme was demonstrated by model studies (15). 

Helen M. I. Osborn, Philip G. Evans, Karel Bezouska ... 

Philip H. Evans, Norbert H. Haunerland, and William S. Bowers Department of Entomology, University of Arizona, Tucson, AZ 85721... 

Submitted by James R. Gage and David A. Evans.1 Checked by Philip G. Meister and Leo A. Paquette... 

Philip, A.T. euid B. Gerson. (1994) Lead poisoning — Part I. Qin. Lab. Med. 14 423-44 Pocock, S.J., M. Smith and P. Baghurst. (1994) Environmental lead and children s intelligence A systematic review of the epidemiological evidence. Br. Med. J. 309 1189-1197 Press, M.F. (1977) Lead encephalopathy in neonatal long-evans rats Morphologic studies. J. Neuropathol. Exp. Neurol. 36 169-193... 

The Value of Business Analytics Identifying the Path to Profitability by Evan Stubbs Visual Six Sigma Making Data Analysis Lean by Ian Cox, Marie A. Gaudard, Philip J. Ramsey, Mia L. Stephens, and Leo Wright... 

LaGrega, Michael D., Philip L. Buckingham, and Jeffrey G. Evans. 2d ed. Hazardous Waste Management. Long Grove, 111. Waveland Press, 2010. Text written for students interested in resolving hazardous-waste problems based on case studies and treatment solutions. 

Ev2 Evans jr., H.T. Technical Report No. 54, Research Lab., Philips Laboratories, Irvington-on-Hudson, N.Y., 1952, 1-33. 

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