Computational Analysis of Amiloride Analogue Inhibitors ofCoxsackievirusB3 RNA Polymerase.
Coxsackievirus B3(CVB3) is a picornavirus that is responsible for a significant proportion of human myocarditis. However, no antiviral treatment is currently available to treat this disease or indeed any picornaviral infections. Previously it was shown that amiloride and its derivative 5-(N-ethyl-N-isopropyl)amiloride inhibit thein vitroenzymatic activity of CVB3 RNA polymerase (3Dpol). Here we measure and compare the inhibitory activity of ten amiloride analogues against CVB3 3Dpol. We show that replacement of the 3,5-diaminopyrazinyl moiety of amiloride causes loss of the inhibitory activity, whereas modifications at the 5-amino and guanidino groups increase or decrease potency. Importantly, a combination of substitutions at both the 5-amino and guanidino groups produced a compound that was more potent than its singly modified precursors. The compounds were computationally-docked into available crystal structures of CVB3 3Dpolin order to obtain a structural explanation for the activities of the analogues. To create a robust model which explained the biological activity, optimization of one of the CVB3 3Dpolcrystal structures to take into account active site flexibility was necessary, together with the use of consensus docking from two different docking algorithms. This robust predictive 3D atomic model provides insights into the interactions required for inhibitor binding and provides a promising basis for the development of more potent inhibitors against this important therapeutic target.
Structural Biology Laboratory and ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria 3065, Australia.
Jessica K
JK
Holien
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.
Elena V
EV
Gazina
School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia.
Robert W
RW
Elliott
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.
Bevyn
B
Jarrott
Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA.
Craig E
CE
Cameron
School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia.
Spencer J
SJ
Williams
Structural Biology Laboratory and ACRF Rational Drug Discovery Centre, St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, Victoria 3065, Australia.|Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia.
Michael W
MW
Parker
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.|Department of Electrical and Electronic Engineering, The University of Melbourne.|Centre for Neural Engineering, The University of Melbourne, Victoria 3010, Australia.
Steven
S
Petrou
Amiloride; Coxsackievirus B3; Drug design; Molecular docking