Nucleoside, -Nucleotide, and -Nucleic Acid Interactions

Metal-Nucleoside, -Nucleotide, and-Nucleic Acid Interactions.—The crystal structure of a cadmium derivative of cytidine 5 -monophosphate [Cd(5 -CMP)(H20)]H20 has been reported, in which cadmium is bonded to the N(3) position oh the base, to a phosphate oxygen from each of three other 5 -CMP groups and to a water molecule. In the crystal of bis-(8-azahypoxanthinato)tetra-aquocadmium(ii), the metal is six co-ordinate, two purines being co-ordinated to cadmium through N(7).  

Manganese and cadmium are both carcinogens and at concentrations of 10 moll induce changes in synthetic polyribonucleotides indicative of base mis-pairing, while Mg and show no effects. 5-Mercuriuridine triphosphate has been used as a probe of in vitro transcription studies, thiol affinity chromatography being used to separate the in vitro synthesized RNA from the cellular RNA. Zn, Cd, and Hg have been found to stimulate RNA and DNA synthesis in chick embryo cultures deprived of serum the stimulation appeared to represent a non-specific event.  

Nicotinamide-(S-methylmercury-thioinosine) dinucleotide was found to exhibit coenzyme properties with lactate dehydrogenase and liver alcohol dehydrogenase, but inactivate yeast alcohol dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase an essential thiol group was therefore modified in the last two cases. 

The penetrability of various thiol reagents through the inner mitochondrial membrane has been tested p-chloromercuribenzoate is a penetrant and inhibited d(—)-j8-hydroxybutyrate dehydrogenase in intact mitochondria on the inside of the mitochondrial membrane. 2-Chloromercuri-4-nitrophenol inhibited the ATPase of intact bovine heart mitochondria, and p-chloromercuribenzoate and mersalyl inhibited the liver microsomal calcium pump. While mersalyl had no effect on the Mg -dependent ATPase, adenylate cyclose from rat liver plasma was inhibited  

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