Search results for "adenine"
showing 10 items of 138 documents
CCDC 724530: Experimental Crystal Structure Determination
2010
Related Article: S.Ikonen, A.Valkonen, E.Kolehmainen|2009|J.Mol.Struct.|930|147|doi:10.1016/j.molstruc.2009.05.006
Influence of agents that act on DNA and RNA synthesis on the activity of poly(ADP-Rib) polymerase
1975
The activity of poly(ADP-Rib) polymerase is enhanced in the presence of spermine and spermidine. Among the adenosine-like antibiotics tested, only formycin B and showdomycin cause an inhibition of the enzyme, which is competitive to NAD. The activity of poly(ADP-Rib) polymerase is not reduced by rifamycin, alpha-amanitin and 2-phenylethanol.
Low density lipoproteins and human serum albumin as the carriers of squalenoylated drugs: insights from molecular simulations
2018
We have studied the interaction of three clinically promising squalenoylated drugs (gemcitabine-squalene, adenine-squalene, and doxorubicin-squalene) with low-density lipoproteins (LDL) by means of atomistic molecular dynamics simulations. It is shown that all studied squalenoylated drugs accumulate inside the LDL particles. This effect is promoted by the squalene moiety, which acts as an anchor and drives the hydrophilic drugs into the hydrophobic core of the LDL lipid droplet. Our data suggest that LDL particles could be a universal carriers of squalenoylated drugs in the bloodstream. Interaction of gemcitabine-squalene with human serum albumin (HSA) was also studied by ensemble of dockin…
Do dynamic effects play a significant role in enzymatic catalysis? A theoretical analysis of formate dehydrogenase.
2010
A theoretical study of the protein dynamic effects on the hydride transfer between the formate anion and nicotinamide adenine dinucleotide (NAD + ), catalyzed by formate dehydrogenase (FDH), is presented in this paper. The analysis of free downhill molecular dynamic trajectories, performed in the enzyme and compared with the reaction in aqueous solution, has allowed the study of the dynamic coupling between the reacting fragments and the protein or the solvent water molecules, as well as an estimation of the dynamic effect contribution to the catalytic effect from calculation of the transmission coefficient in the enzyme and in solution. The obtained transmission coefficients for the enzyme…
Differential mode of inhibition of terminal deoxynucleotidyl transferase by 3′-dATP, ATP, βaraATP and αaraATP
1978
Long-term stability study of clofarabine injection concentrate and diluted clofarabine infusion solutions
2011
Purpose: The aim of this study was to investigate the physicochemical stability of clofarabine (CAFdA) injection concentrate and ready-to-use CAFdA infusion solutions over a prolonged period of 28 days. Methods: To determine the stability of CAFdA infusion solutions, the injection concentrate (Evoltra®, 1 mg/mL, Genzyme) was diluted either with 0.9% sodium chloride or 5% glucose infusion solution. The resulting concentrations of 0.2 mg/mL or 0.6 mg/mL, respectively, were chosen to represent the lower and upper limit of the ordinary concentration range. Test solutions were stored under refrigeration (2–8°C) or at room temperature either light protected or exposed to light. CAFdA concentrati…
Alkaloids Isolated from Somatic Hybrid Cell Cultures of the Species CombinationRauwolfia serpentinaxrhazya stricta
1995
Abstract The phytochemical analyses of a somatic hybrid cell suspension culture of the genus and species combination Rauwolfia serpentina x Rhazya stricta revealed a number of monoterpenoid indole alkaloids. The alkaloids were identified as tubotaiwine, an isomeric mixture of vallesiachotamine, stemmadenine and vomilenine and were all produced in small amounts < 2mg/litre cell suspension. The hybrid cells showed a greater diversity of alkaloid biosynthesis when compared with the parental cultures.
On the Deactivation Mechanisms of Adenine–Thymine Base Pair
2012
In this contribution, the multiconfigurational second-order perturbation theory method based on a complete active space reference wave function (CASSCF/CASPT2) is applied to study all possible single and double proton/hydrogen transfers between the nucleobases in the adenine-thymine (AT) base pair, analyzing the role of excited states with different nature [localized (LE) and charge transfer (CT)], and considering concerted as well as step-wise mechanisms. According to the findings, once the lowest excited states, localized in adenine, are populated during UV irradiation of the Watson-Crick base pair, the proton transfer in the N-O bridge does not require high energy in order to populate a …
UV-induced cross-linking of proteins to plasmid pBR322 containing 8-azidoadenine 2′-deoxyribonucleotides
1988
Abstract An efficient method of cross-linking DNA to protein is described. The method is based on the incorporation of photoactive 8-azidoadenine 2′-deoxyribonucleotides into DNA. We have found that 8-N 3 dATP is a substrate for E. coli DNA polymerase I and that 8-N 3 dATP can be incorporated into plasmid pBR322 by nick-translation. Subsequently we were able to cross-link a set of different proteins to 8-azido-2′-deoxyadenosine-containing pBR322 by UV irradiation (366 nm). No DNA-protein photocross-linking was observed under the same conditions when the non-photoactive plasmid pBR322 was used.
Complete-active-space second-order perturbation theory (CASPT2//CASSCF) study of the dissociative electron attachment in canonical DNA nucleobases ca…
2015
Low-energy (0-3 eV) ballistic electrons originated during the irradiation of biological material can interact with DNA/RNA nucleobases yielding transient-anion species which undergo decompositions. Since the discovery that these reactions can eventually lead to strand breaking of the DNA chains, great efforts have been dedicated to their study. The main fragmentation at the 0-3 eV energy range is the ejection of a hydrogen atom from the specific nitrogen positions. In the present study, the methodological approach introduced in a previous work on uracil [I. González-Ramírez et al., J. Chem. Theory Comput. 8, 2769-2776 (2012)] is employed to study the DNA canonical nucleobases fragmentations…