Search

Your search keyword '"Bauer, Cary B."' showing total 47 results
Start Over Author "Bauer, Cary B."
47 results on '"Bauer, Cary B."'

3. Three-dimensional structure of the L-threonine-O-3-phosphate decarboxylase (CobD) enzyme from Salmonella enterica

Author

Cheong, Cheom-Gil, Bauer, Cary B., Brushaber, Kevin R., Escalante-Semerena, Jorge C., and Rayment, Ivan

Subjects
Proteins -- Structure, Structure-activity relationships (Biochemistry) -- Analysis, Decarboxylases -- Research, Aminotransferases -- Research, Biological sciences, Chemistry
Abstract

The three-dimensional structure of L-threonine-O-3-phosphate decarboxylate complexed with the pyridoxal 5'-phosphate reveals that the structure is very similar to that of aspartate- and histidinol aminotransferases, suggesting an evolutionary trend within the conserved class of aminotransferases.

Published
2002

4. Three-dimensional structure of ATP:corrinoid adenosyltransferase from Salmonella typhimurium in its free state, complexed with MgATP, or complexed with hydroxycobalamin and MgATP

Author

Bauer, Cary B., Fonseca, Maris V., Holden, Hazel M., Thoden, James B., Thompson, Thomas B., Escalante-Semerena, Jorge C., and Rayment, Ivan

Subjects
Biochemistry -- Research, Adenosine triphosphate -- Research, Salmonella typhimurium -- Physiological aspects, Magnesium (Nutrient) -- Physiological aspects, Cobalt -- Physiological aspects, Carbon -- Physiological aspects, Biological sciences, Chemistry
Abstract

Research has been conducted on the ATP:corrinoid adenosyltransferase from Salmonella typhimurium. The X-ray structure of this adenosyltransferase in its substrate-free state complexed with MgATP and in the ternary complex with CobA and MgATP has been investigated.

Published
2001

6. X-ray structures of the MgADP, MgATPgammaS, and MgAMPPNP complexes of the Dictyostelium discoideum myosin motor domain

Author

Gulick, Andrew M., Bauer, Cary B., Thoden, James B., and Rayment, Ivan

Subjects
Myosin -- Research, Dictyostelium -- Research, Biological sciences, Chemistry
Abstract

The three-dimensional structures of the truncated myosin head from Dictyostelium discoideum myosin II (S 1 dC) complexed with MgAMPPNP, MgATPgammaS and MgADP were investigated. The overall structures of all three complexes were very close to that of the beryllium fluoride complex. This indicates that the differences in the physiological effects of ATPgammaS and AMPPNP are caused by alterations in the equilibrium between the actin-bound and actin-free states of myosin due to the lower affinity of AMPPNP for myosin.

Published
1997

7. Study of the rearrangements of oxonium ylides generated from ketals

Author

Brogan, John B., Zercher, Charles K., Bauer, Cary B., and Rogers, Robin D.

Subjects
Cyclic compounds -- Research, Oxo compounds -- Research, Rearrangements (Chemistry) -- Research, Biological sciences, Chemistry
Abstract

A competition between six-membered ring bicyclic ylide formation and C-H insertion during the formation of oxonium ylides from ketones was analyzed to characterize the kinetics of the reaction. A generation of the oxonium ylide via the intramolecular exposure of cyclic crystals to metal carbenoids was characterized by bicyclic ylide rearrangement. Furthermore, the rearrangement of oxonium ylides was affected by the ring-size of the intermediate bicyclic ylide and the nature of the substituents on the ketal.

Published
1997

9. Transition metal complexes of p-sulfonatocalix(5)arene

Author

Johnson, Carl P., Atwood, Jerry L., Steed, Jonathan W., Bauer, Cary B., and Rogers, Robin D.

Subjects
Transition metal compounds -- Research, Inorganic compounds -- Research, Chemistry
Abstract

Previous research has established a binding mode for transition metal ion complexes in lanthanide species. A similar binding mode is established for transition metal ion complexes in p-sulfonatocalix(5)arene. It is shown that the calixarene formation is highly mobile and varies according to the steric and electronic needs of the guest. Aromatic hydrogen bonding by included water is not shown, presumably as a result of the calix(5)arene cavity's large size.

Published
1996

10. Effects of polyethylene glycol on the coordination sphere of strontium in SrCl2 and Sr(NO3)2 complexes

Author

Rogers, Robin D., Jezl, Mary L., and Bauer, Cary B.

Subjects
Coordination compounds -- Research, Strontium -- Research, Glycols -- Research, Chemistry
Abstract

Syntheses of nine different directly coordinated complexes involve the stoichiometric reactions of Sr(NO3)2 or SrCl2.6H2O with various polyethylene glycols, in a medium of CH3CN. X-ray crystallographic studies reveal that glycols exhibit similar conformations in all the nine complexes. Glycols favor the formation of pseudocyclized in-cavity crown ether-like complexes. X-ray analysis enables the evaluation of Sr-O (alcoholic) and Sr-O (etheric) separations.

Published
1994

11. Structural investigation into the steric control of polyether complexation in the lanthanide series: macrocyclic 18-crown-6 versus acylic pentaethylene glycol

Author

Rogers, Robin D., Rollins, Andrew N., Etzenhouser, Russell D., Voss, Eric J., and Bauer, Cary B.

Subjects
Rare earth metals -- Research, Hydrogen bonding -- Analysis, Crown ethers -- Observations, Chemistry
Abstract

The polyethylene glycols (PEG's) complexes of MCl3.nH2O exhibit total steric control of the primary coordination sphere, and its structure is compared to that of macrocyclic 18-crown-6. The similar features observed between the crystal structures of the species of the pentaethylene glycol (EO5) lenthamid complexes and 18-crown-6 complexation induces the flexible cavity in 18-crown-6. The differences in the structural features arise due to the cyclic and less flexible natures of 18-crown-6 compared to EOS. PEG complexes of MCl3. nH2O are easily isolated due to their flexible nature.

Published
1993

15. Molecular structure of the rat vitamin D receptor ligand binding domain complexed with 2-carbon-substituted vitamin D3 hormone analogues and a LXXLL-containing coactivator peptide

Author

Vanhooke, Janeen L., Benning, Matthew M., Bauer, Cary B., Pike, J. Wesley, and DeLuca, Hector F.

Subjects
Rats as laboratory animals -- Testing, Calcifediol -- Analysis, Alfacalcidol -- Analysis, Vitamin D -- Analysis, Ligand binding (Biochemistry) -- Research, Ligand binding (Biochemistry) -- Structure, Biological sciences, Chemistry
Abstract

The crystal structures of the ligand binding domain (LBD) of the rat vitamin D receptor (VDR) in ternary complexes with a synthetic LXXLL-containing peptide and four ligands are determined. The differences in the biological activity of the 2-carbon-modified analogues are not reflected in the three-dimensional structure of the LBD of the VDR.

Published
2004

16. Conformational analysis of poly(spirotetrahydrofuranyl)cyclohexyl systems. The preference of multiple C-O bonds for equatorial occupancy

Author

Paquette, Leo A., Stepanian, Marshall, Branan, Bruce M., Edmondson, Scott D., Bauer, Cary B., and Rogers, Robin D.

Subjects
Cyclic compounds -- Research, Conformational analysis -- Observations, Chemical bonds -- Analysis, Chemistry
Abstract

C-O bonds in poly(spirotetrahydrofuranyl)cyclohexyl systems prefer to occupy equatorial positions, and the resulting conformer with two axial and four equatorial C-O bonds has the maximum stability. With C-O bonds present in the equatorial positions, the 1,3-diaxial interactions are reduced. The cyclohexane ring system containing flattened cyclohexane chairs exhibits buttressing. The spirocyclic pendant rings have restricted rotational degrees of freedom.

Published
1996

18. Nickel(ii), copper(ii) and zinc(ii) binding properties and cytotoxicity of tripodal, hexadentate tris(ethylenediamine) ? analogue chelators

Author

Ye, Neng, primary, Park, Gyungse, additional, Przyborowska, Ann M., additional, Sloan, Paula E., additional, Clifford, Thomas, additional, Bauer, Cary B., additional, Broker, Grant A., additional, Rogers, Robin D., additional, Ma, Rong, additional, Torti, Suzy V., additional, Brechbiel, Martin W., additional, and Planalp, Roy P., additional

Published
2004
Full Text
View/download PDF

19. Steric effects caused by N-alkylation of the tripodal chelator N,N′,N″-tris(2-pyridylmethyl)-cis,cis-1,3,5-triaminocyclohexane (tachpyr): structural and electronic properties of the Mn(ii), Co(ii), Ni(ii), Cu(ii) and Zn(ii) complexes

Author

Park, Gyungse, primary, Przyborowska, Ann M., additional, Ye, Neng, additional, Tsoupas, Nicole M., additional, Bauer, Cary B., additional, Broker, Grant A., additional, Rogers, Robin D., additional, Brechbiel, Martin W., additional, and Planalp, Roy P., additional

Published
2002
Full Text
View/download PDF

42. Three-Dimensional Structure of the L-Threonine-0-3-phosphate Decarboxylase (CobD) Enzyme from Salmonella entercia.

Author

Cheom-Gil Cheong, Bauer, Cary B., Brushaber, Kevin R., Escalante-Semerena, Jorge C., and Rayment, Ivan

Subjects
*ENZYMES, *SALMONELLA, *DECARBOXYLASES
Abstract

Examines the three-dimensional structure of the L-threonine-0-3-phosphate decarboxylase enzyme from Salmonella enterica. Role of the enzyme in synthesizing (R)-1-propanol phosphate; Linkage between the nucleotide loop and the corrin ring in cobalamin; Arrangement of ligands surrounding the cofactor.

Published
2002
Full Text
View/download PDF

43. Three-Dimensional Structure of ATP: Corrinoid Adenosyltransferase from Salmonella typhimurium in...

Author

Bauer, Cary B., Fonseca, Maris V., Holden, Hazel M., Thoden, James B., Thompson, Thomas B., Escalante-Semerena, Jorge C., and Rayment, Ivan

Subjects
*TRANSFERASES, *CHEMICAL bonds, *SALMONELLA typhimurium, *ADENOSINE triphosphate, *CHEMICAL structure
Abstract

Reports on the structure of adenosine triphosphate (ATP):corrinoid adenosyltransferase from Salmonella typhimurium in its substrate-free state, complexed with MgATP or with hydroxocobalamin and MgATP. Formation of the cobalt-carbon bond; MgATP and hydroxocobalamin binding sites; Interactions between the protein and polar side chains of corrin ring.

Published
2001
Full Text
View/download PDF

45. Nickel(ii), copper(ii) and zinc(ii) binding properties and cytotoxicity of tripodal, hexadentate tris(ethylenediamine) – analogue chelators

Author

Ye, Neng, Park, Gyungse, Przyborowska, Ann M., Sloan, Paula E., Clifford, Thomas, Bauer, Cary B., Broker, Grant A., Rogers, Robin D., Ma, Rong, Torti, Suzy V., Brechbiel, Martin W., and Planalp, Roy P.

Abstract

Three tripodal hexamine chelators based on cis,cis-1,3,5-triaminocyclohexane (tach) have been synthesized and their aqueous coordination chemistry with Ni(ii), Cu(ii) and Zn(ii) is reported. The chelators have a 2-aminoethyl pendant arm attached to each nitrogen of tach, specifically ‘tachen’ (N,N',N"-tris(2-aminoethyl)cyclohexane-cis,cis-1,3,5-triamine), and two with S,S,S-chiral pendant arms, ‘tachpn’ (N,N',N"-tris(2-aminopropyl)cyclohexane-cis,cis-1,3,5-triamine) and ‘tachbn’ (N,N',N"-tris(2-amino-3-phenylpropyl)cyclohexane-cis,cis-1,3,5-triamine. These chelators complex Ni(ii), Cu(ii) and Zn(ii) in aqueous or aqueous/methanolic medium. The crystalline products [MIIL](X)2 are isolated, where M = Ni(ii), Cu(ii) or Zn(ii), L = tachen, tachpn or tachbn, and X = ClO4−. Crystallographic study of selected tachpn and tachbn complexes shows the chelate arms are constrained in a Λ(δδδ) configuration about M(ii), which is attributed to their chirality. Solution UV-vis spectroscopy of the Ni(ii) and Cu(ii) complexes indicates six-coordination and little effect of the pendant arm substitution on ligand-field strength. The single exception is [Cu(tachbn)]2+, whose spectrum is consistent with five-coordination in solution. The cytotoxicities of tachen, tachpn and tachbn toward cultured cancer cells is in the order tachen < tachpn < tachbn < tachpyr, where tachpyr is the aminopyridyl chelator N,N',N"-tris(2-pyridylmethyl)cyclohexane-cis,cis-1,3,5-triamine. The cytotoxicity difference is attributed to an order of increasing lipophilicity, tachen < tachpn < tachbn.

Published
2004

46. Steric effects caused by N-alkylation of the tripodal chelator N,N',N"-tris(2-pyridylmethyl)-cis,cis-1,3,5-triaminocyclohexane (tachpyr): structural and electronic properties of the Mn(ii), Co(ii), Ni(ii), Cu(ii) and Zn(ii) complexes

Author

Park, Gyungse, Przyborowska, Ann M., Ye, Neng, Tsoupas, Nicole M., Bauer, Cary B., Broker, Grant A., Rogers, Robin D., Brechbiel, Martin W., and Planalp, Roy P.

Abstract

The effects of steric hindrance on the complexation of Mn(ii), Co(ii), Ni(ii), Cu(ii) and Zn(ii) by chelators based on cis,cis-1,3,5-triaminocyclohexane (tach) have been studied. The chelators studied are the 2-methylpyridyl pendant-arm derivatives of tach, ‘tachpyr’ (N,N',N"-tris(2-pyridylmethyl)-cis,cis-1,3,5-triaminocyclohexane), and the N-alkylated analogs ‘(N–Me)3tachpyr’ (N,N',N"-trimethyl-N,N',N"-tris(2-pyridylmethyl)-cis,cis-1,3,5-triaminocyclohexane) and ‘(N–Et)3tachpyr’ (N,N',N"-triethyl-N,N',N"-tris(2-pyridylmethyl)-cis,cis-1,3,5-triaminocyclohexane). Hexacoordinate complexes, [MiiL]X2 resulted from reaction of the appropriate metal ion salts with L in alcoholic medium (M = Mn, Co, Ni, Cu, Zn; L = tachpyr, (N–Me)3tachpyr, (N–Et)3tachpyr; X = ClO4−, NO3−, Cl−). The Mn(ii) and Co(ii) complexes have high-spin electron configurations, based on solution magnetic susceptibility, electronic spectral and/or X-ray crystallographic studies. However, solution visible-near IR electronic spectra and single-crystal X-ray crystallography demonstrate weakened bonding in the complexes of (N–R)3tachpyr relative to tachpyr, due to steric effects of methyl or ethyl groups on coordinated tach amines. Structures of [Zn(tachpyr)]2+ and [Ni(tachpyr)]2+ indicate a clear preference of tachpyr and derivatives for octahedral geometry, while [Cu((N–Me)3tachpyr)]2+ exhibits a classic Jahn–Teller tetragonal distortion. The complex [Mn(tachpyr)](ClO4)2 demonstrates a striking influence of the metal ion on the coordination geometry, with a trigonal-prismatic coordination of Mn(ii) and considerable distortion of the tach-amino donor groups. The coordination geometry and distortions are attributed to the large size of high-spin d5 Mn(ii) and the absence of ligand-field stabilization energy, coupled with the observed preference of tachpyr derivatives for octahedral geometry. The [Mii(tachpyr)]2+ complexes (M = Co, Ni, Cu and Zn) are inert in aqueous pH 5.5 media. However, all metal complexes of N-alkylated tachpyr, as well as [Mn(tachpyr)](ClO4)2, dissociate metal ion in aqueous pH 5.5 medium, consistent with their steric hindrance and distortions respectively.

Published
2003

Catalog

Books, media, physical & digital resources
See catalog results