Nucleic acid derivatives detailed experiments

Unidimensional TLC of nucleic acid derivatives has been done on cellulose. Thus, Bij and Lederer (1983) used TLC on plastic sheets coated with cellulose to separate nucleic acid bases and nucleosides water or aqueous solutions of (NH4)2S04 were used as mobile phases and the chromatography was done at room temperature using small glass jars covered with watch glasses. Detailed Experiment 1 of this chapter describes a unidimensional separation of nucleotides on PEI-cellulose. 

Unidimensional TLC of nucleic acid derivatives has also been done on silica gel. Issaq et al. (1977) separated mixtures of alkylated guanines, adenines, uracils, and cytosines on silica gel 6OF2S4, in various chloroform-alcohol solvent systems. The addition of 1 ml of ammonium hydroxide to the mobile phase prevented streaking and resulted in nondistorted developed spots. Figueira and Ri-beiro (1983) separated adenine, adenosine, inosine, hypoxanthine, 2-AMP, 5-AMP, ADP, ATP, cAMP, and dibutyryl cAMP also on silica gel 6OF254, and Sleckman et al. (1985) used conventional and high-performance silica gel to separate four representative nucleotides and their corresponding nucleosides. Detailed Experiment 2 of this chapter describes a unidimensional separation of nucleotides and nucleosides on silica gel. 

The patterns of autocatalysis with respect to parabolic and exponential reaction courses, which strongly affect the conclusions of Eigen s evolution experiments concerning the decision criteria for mutant selection and coexistence [5 b, 40 h, k], can now be derived from the thermodynamic data of the matrix patterns and their reactivities, and offer quite new views, with autocatalytic cooperation between competitive species [40 k]. Separate from enzyme-catalyzed evolution experiments with RNA and DNA systems, basic questions of prebiotic behavior can for the first time become the subject of detailed experimental research [40 k, 43]. While continuing their studies on more complex autocatalysis patterns, von Kie-drowski et al. diagnosed modulation of molecular recognition as an operational deficit of earlier artificial self-replicational nucleic acid systems with regard to exponential reaction courses, and identified it as an ideal aim for future models [44]. On its way to the nucleoprotein system, evolution must have... 

RNA was not a precursor in the synthesis of virus DNA and was essentially inert in infected cells. Shortly afterwards, Putnam and Kozloff (258) reported that T6, like T2 and T4, derives about 70% of its P from the medium and the remainder from the host cell, but from experiments with differentially labeled cells, they reasoned that bacterial DNA rather than acid-soluble P was the major source of the host contribution to virus DNA. More detailed studies with differentially labeled cells have substantiated the conclusions for T6r+ (162,287), and investigation of the kinetics of P assimilation into virus nucleic acid has confirmed these... 

The synthesis of virus protein has not been worked out in any such detail as has that of nucleic acid. The only information comes from 3 sources (1) chemical balance studies already reviewed, (2) tracer studies of the origin of the N of T6 and T7 phages (160,163,262), and (3) a single investigation of the metabolism of lysine in cells infected with T6 (287). From the origin experiments it was found that a very small fraction of the protein N of T6 was derived from the host cell. This indicates that most of the virus protein is formed from extracellular ammonia by a... 

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