<Tr> <Th_colspan="3"> Novel basepairs with special properties </Th> </Tr> <Tr> <Td> </Td> <Td> </Td> <Td> </Td> </Tr> <Tr> <Td> A F-Z base: methylbenzimidazole does not form intermolecular hydrogen bonds with toluene F / F </Td> <Td> An S - Pa base: purine thienyl / amine forms three intermolecular hydrogen bonds with pyrrole - / carbaldehyde </Td> <Td> An xA - T base: same bonding as A-T </Td> </Tr> <P> In metal base - pairing, the Watson - Crick hydrogen bonds are replaced by the interaction between a metal ion with nucleosides acting as ligands . The possible geometries of the metal that would allow for duplex formation with two bidentate nucleosides around a central metal atom are: tetrahedral, dodecahedral, and square planar . Metal - complexing with DNA can occur by the formation of non-canonical base pairs from natural nucleobases with participation by metal ions and also by the exchanging the hydrogen atoms that are part of the Watson - Crick base pairing by metal ions . Introduction of metal ions into a DNA duplex has shown to have potential magnetic, conducting properties, as well as increased stability . </P>

Nucleotide or nucleoside are antimicrobial agents that mimic the chemical structure