Science Letter
January 9, 2007
LIFE SCIENCES;
Reports outline life sciences study findings from Yerevan State
University, Department of Molecular
Scientists discuss in "Thermodynamics of interactions of TAlPyP4 and
AgTAlPyP4 porphyrins with poly(rA)poly(rU) and poly(rI)poly(rC)
duplexes" new findings in life sciences. "We employed UV light
absorption and circular dichroism (CD) spectroscopic measurements to
study the binding of novel water-soluble porphyrins
meso-tetra-(4N-allylpyridyl)porphyrin [TAlPyP4], and its Ag
containing derivative to the poly(rA)poly(rU) and poly(rI)poly(rC)
RNA duplexes. Our results suggest that TAlPyP4 associate with the
duplexes via intercalation, whereas the conservative CD spectra
indicates that AgTAlPyP4 preferably binds via outside self-stacking
mode," scientists writing in the Journal of Biomolecular Structure
and Dynamics report.
"We used our determined binding isotherms for each ligand-RNA binding
event to calculate the binding constant, Kb, and binding free energy,
DeltaGb=-RTlnKb. By performing these experiments as a function of
temperature, we evaluated the van’t Hoff binding enthalpies, DeltaH.
The binding entropies, DeltaSb, were calculated as DeltaSb=(DeltaHb
-DeltaGb)/T. We interpret our data in terms of specific interactions
that stabilize/destabilize each ligand-RNA complex studied in this
work," wrote A.A. Ghazaryan and colleagues, Yerevan State University,
Department of Molecular.
The researchers concluded: "Taken together, our data provide
important new information about the thermodynamics of interactions of
porphyrins with nucleic acids."
Ghazaryan and colleagues published their study in the Journal of
Biomolecular Structure and Dynamics (Thermodynamics of interactions
of TAlPyP4 and AgTAlPyP4 porphyrins with poly(rA)poly(rU) and
poly(rI)poly(rC) duplexes. Journal of Biomolecular Structure and
Dynamics, 2006;24(1):67-74).
Additional information can be obtained by contacting A.A. Ghazaryan,
Faculty of Physics, Dept. of Molecular Physics, Yerevan State
University, 1 Alex Manoogian Street, Yerevan 375025, Armenia.
The publisher of the Journal of Biomolecular Structure and Dynamics
can be contacted at: Adenine Press, 2066 Central Avenue, Schenectady,
NY 12304, USA.
From: Emil Lazarian | Ararat NewsPress