Sensing biological effectors through the response of bridged nucleic acids and polynucleotides fixed in liquid-crystalline dispersions.
The formation of three-dimensional structures of double-stranded nucleic acid and polynucleotide molecules, fixed in the structure of liquid-crystalline dispersions and bridged by polymeric chelate complexes is described. The bridging elements consist of alternating daunomycin molecules and copper ions. It is shown that these bridges between nucleic acid molecules stabilize cholesteric structures of the DNA liquid-crystalline dispersion. The formation of polymeric chelate bridges is accompanied by a remarkable increase of the intense circular dichroism (CD) band characteristic of the DNA-daunomycin cholesterics. These bridges are destabilized by a number of biologically relevant compounds and macromolecules, such as ascorbic acid, homocarnosine, bovine serum albumin and lysozyme. The dramatic change in the optical activity of the liquid-crystalline dispersions upon addition of these compounds makes them easily detectable. The sensitivity of the method, in the range of analytic concentration 10(-4)-10(-8) M, depends on the nature of the compound being tested. The response of bridged DNA structures to biological effectors observed here foresees their further development as biosensor devices for detecting the presence of biologically and pharmacologically relevant compounds.
Yevdokimov YuM
Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.
Salyanov
V I
VI
Lortkipanigze
G B
GB
Gedig
E
E
Spener
F
F
Palumbo
M
M
D001205:Ascorbic Acid / Q000737:chemistry; D015374:Biosensing Techniques; D002614:Chelating Agents; D002942:Circular Dichroism; D003300:Copper; D003460:Crystallization; D046911:Macromolecular Substances; D009696:Nucleic Acids / Q000737:chemistry*; D009994:Osmolar Concentration; D011119:Polynucleotides / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry
D002614:Chelating Agents; D046911:Macromolecular Substances; D009696:Nucleic Acids; D011119:Polynucleotides; D012710:Serum Albumin, Bovine; D003300:Copper; D001205:Ascorbic Acid