Bacteriophages kinetics

Temperature jump studies on the binding dynamics of 5 with ct-DNA and T2 Bacteriophage DNA showed two lifetimes in the relaxation kinetics.117 The observed... 

The non-linear dependence of the relaxation process on the DNA concentration was also observed in stopped-flow experiments and the same mechanism, i.e. fast pre-equilibrium followed by a slow intercalation step, was proposed." This latter study did not report values for the individual rate constants. The mechanism proposed in Scheme 4 was employed in subsequent studies despite the criticism on the accuracy for the data related to the fast kinetic component (see below). The original temperature jump study also showed that the relaxation kinetics depend on the structure of the DNA.117 The slower intercalation rate for 5 with T2 Bacteriophage DNA when compared to ct-DNA was ascribed to the glucosylation of the former DNA (Table 3). 

Prokaryotic DNA polymerases are so accurate that special kinetic assays have had to be introduced to detect errors in vitro. These depend on replicating under controlled conditions the circular DNA of a small bacteriophage that contains a... 

Furge, L.L. and Guengerich, F.P. (1998) Pre-steady-state kinetics of nucleotide insertion following 8-oxo-7,8-dihydro-guanine base pair mismatches by bacteriophage T7 DNA polymerase exo. Biochemistry, 37, 3567-3574. 

Zang, H., Harris, T.M., and Guengerich, F.P. (2005) Kinetics of nucleotide incorporation opposite DNA bulky guanine N2 adducts by processive bacteriophage T7 DNA polymerase (exonuclease-) and HIV-1 reverse... 

Pre-steady-state (or transient-state) kinetic approaches, allowing the dissection of individual steps and intermediates in an enzymatic reaction, are superior to classical steady-state approaches. Pre-steady-state kinetic methods were first applied to DNA polymerases in late 1980s to early 1990s in classical studies of E. coli Pol I (Klenow fragment, and bacteriophage T7 DNA polymerase. These studies have served as a... 

Comparable kinetic parameters were observed in independent mutagenesis studies of calcineurin [39] and bacteriophage X protein phosphatase [24] ... 

Stuait, J., Salaices, M., Valvano M. and de Lasa H., 2003 Photocatalytic inactivation of MS2 bacteriophage andE.coli. Kinetics modeling and quantum efficiency. Proc. 18 North American Catalysis Symp. pp247... 

DNA polymerases perform essential roles in the replication and repair of genetic material. The DNA polymerases of several mesophiles have been extensively characterized, and the structural, biochemical, and kinetic properties of Escherichia coli, yeast, mammalian, and bacteriophage DNA polymerases have been the subject of numerous reviews. " Certain enzymes complement DNA polymerase activity with 3 - -5 -exonuclease (proofreading) activity and/or 5 - 3 -exonuclease activity, which typically reside in separate structural domains on the same polypeptide. To orchestrate DNA replication and repair, both eubacteria and eukaryotes possess multiple DNA polymerases, each with distinct properties, subunit compositions, and physiological roles. In vivo, DNA polymerases require the assistance of numerous accessory proteins to replicate and repair the genome (reviewed ). Based on amino acid sequence homology to E. coli enzymes, DNA polymerases have been classified into at least three distinct families Family A (Pol I-like), Family B (Pol Il-like), and Family C (Pol Ill-like). ... 

Encouraged by these results, we next asked whether isolated, purified mitochondria were capable of producing the same modification product. The data shown in Fig. 8C show that they do. It should also be noted that both in vivo and in vitro, the mtDNA cosediments precisely with the DNA of bacteriophage T7 (5 = 32.05 S Mr = 25 x 10 ) and assumes a distribution centered on molecules half that size after its exposure to, and association with, EtdBr. We also compared both the kinetics and the stoichiometry of the reaction, which may be formulated as... 

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