Cezar Bendic

Department of Physical Chemistry, Faculty of Chemistry, University of Bucharest,

 Blvd. Elisabeta 4-12, Bucharest RO-70346, Romania


          This program was especially conceived in order to identify and analyze intermolecular interactions in biopolimers.

         SHB_interactions is a program based on Extended Hückel calculation that uses the Mulliken overlap populations as a quantitative quantum chemical criterion, able to measure the strength of hydrogen bonds and other atom-atom intermolecular interactions. 

          Differing from the previous  HBplus  and  HBexplore  programs, based on arbitrary geometrical criteria, which outlines only the potential hydrogen bonds, this program allows an estimate of the contribution of every atom-atom intermolecular   interaction to the stabilization of both DNA and RNA as well as the drug-nucleic acid complex. 

        In this program, the Mulliken overlap populations calculated in the frame of the Extended Hückel method are used for the evaluation of the interaction strength. Due to its molecular size, it is impossible to  use a  quantum chemical method to compute the electronic structure of a nucleic acid. Therefore  the calculation is  performed on the  base-base  or base-drug pairs after their cutoff  from the biopolimer structure and the addition of the atoms needed to complete nucleotide structures.  

         Our theoretical results underline that, besides classical hydrogen bonds, the other  types of  atom-atom intermolecular interactions have a significant contribution to the specific interaction of the drug with nucleic acids


            A description of the program and examples for its application will be available soon.

        To receive a copy of SHB_interactions please fill out the license agreement and send me your name and affiliation. The source code written in C will be distributed via e-mail.