TY  - JOUR
AU  - Akola, J.
AU  - Jones, R. O.
TI  - Density functional calculations of ATP systems I: Crystalline ATP hydrates and related molecules
JO  - The journal of physical chemistry  / B
VL  - 110
SN  - 1520-6106
CY  - Washington, DC
PB  - Soc.
M1  - PreJuSER-51047
SP  - 8110 - 8120
PY  - 2006
N1  - Record converted from VDB: 12.11.2012
AB  - Adenosine 5'-triphosphate (ATP) is an essential energy carrier in mammalian and other cells, and its hydrolysis to the diphosphate (ADP) in the presence of metal cations (e.g., Mg(2+) or Ca(2+)) is one of the most prevalent biochemical reactions. We describe here density functional (DF) calculations on closely related systems and compare the results with other calculations and available experimental data: Na(H2O)n +, Mg(H2O)n 2+, and Ca(H2O)n 2+ clusters (n = 1, 4-7), the crystalline pyrophosphates Mg(2)P(2)O(7).6H2O and alpha-CaNa(2)P(2)O(7).4H2O, and crystalline Na(2)ATP.3H2O. The last of these comprises asymmetric units of ATP dimers (monomers A and B) in a double-protonated state H(2)(ATP)(2-). The calculated structures agree well with available measurements and provide additional information, including the location of the H atoms. Analysis of the dipole moments of individual ATP monomers and their dimers shows that the crystal comprises blocks of opposing dipoles. Replacing one Na+ ion with Mg2+ or Ca2+ results in a significant elongation of the terminal bridging P-O bond. The calculations provide benchmarks for the use of DF methods in ATP systems and are used in the companion paper to study the hydrolysis of ATP at the active site of the protein actin.
KW  - Adenosine: chemistry
KW  - Adenosine Triphosphate: chemistry
KW  - Cations: chemistry
KW  - Crystallization
KW  - Models, Molecular
KW  - Molecular Conformation
KW  - X-Ray Diffraction
KW  - Cations (NLM Chemicals)
KW  - Adenosine Triphosphate (NLM Chemicals)
KW  - Adenosine (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:16610914
UR  - <Go to ISI:>//WOS:000236992100068
DO  - DOI:10.1021/jp054920l
UR  - https://juser.fz-juelich.de/record/51047
ER  -