title: Ethidium cooperativity in the formation of complexes with CpG.
abstract: The formation of complexes between the self-complementary ribo-dinucleoside monophosphate CpG and ethidium ion is observed by use of an ethidium ion selective electrode. The ratio of total CpG to total ethidium was varied from 50:1 to .4:1, with CpG concentrations ranging from 0.2 to 1.1 mM. Scatchard plots show that the system is strongly cooperative with respect to ethidium ion; cooperativity with respect to dinucleoside has been previously reported (Krugh, T.R., Wittlin, F.N., and Cramer, S.P. (1975) Biopolymers 14,197-210). Cooperative behavior with respect to ethidium ion implies the existence of complexes containing at least two molecules of ethidium ion in combination with one or more CpG molecules.
mesh_terms: D003568:Cytidine Monophosphate / Q000031:analogs & derivatives / Q000378:metabolism*; D003597:Cytosine Nucleotides / Q000378:metabolism*; D015226:Dinucleoside Phosphates; D004566:Electrodes; D004996:Ethidium / Q000378:metabolism*; D006151:Guanosine / Q000031:analogs & derivatives* / Q000378:metabolism; D007700:Kinetics; D011108:Polymers / Q000378:metabolism
chemical_list: D003568:Cytidine Monophosphate; D003597:Cytosine Nucleotides; D015226:Dinucleoside Phosphates; D004996:Ethidium; D006151:Guanosine; D011108:Polymers; C015772:CpG dinucleotide