In silico evaluation of anti-retroviral effects of lactoferrin from different species

Ali Javadmanesh ,1,* Marjan azghandi,2

1. Ferdowsi University of Mashhad
2. Ferdowsi University of Mashhad

Abstract

Introduction

Lactoferrin (lf) is an iron binding glycoprotein that is present in body fluids and mucosal secretions. antimicrobial properties of lf against bacteria, fungi and several viruses have been approved in a large number experiments. lf prevents entry of virus in the host cell, either by blocking cellular receptors, or by direct binding to the virus particles. rotavirus is a member of the reoviridae-family which is the most frequent cause of non-bacterial gastroenteritis in neonates and children, killing approximately one million people each year. it has been approved that lf or its derivatives not only prevents infection, but also maintains an antiviral effect after the virus has penetrated the cell. a comprehensive study comparing anti-retroviral properties of lfs derived from different species of farm animal and human has not yet assessed. in the current study, in silico evaluation of antiviral effects of lactoferrin from different species such as cattle, sheep, goat, double and single-humped camel, horse, buffalo and human against retrovirus was evaluated by a protein-protein docking approach.

Methods

The crystal structures of human, cattle, goat, horse, domestic water buffalo and single humped camel lactoferrin were retrieved from the uniprot (http://www.uniprot.org/), and the protein structure of sheep, zebo cattle and double-humped camel lactoferrin were predicted by the i tasser server. the results were validated using saves server. the crystal structures of rotavirus capsid proteins vp5 and vp8 were retrieved from the protein data bank (http://www.rcsb.org) (pdb id: 4v7q) then the pdb files prepared for docking calculation. autodock 4.2.6 was used for protein docking. a grid box of 126×126×126 points with 0.153 Å spacing was defined. running a docking using the lamarckian ga, there were a number of parameters to set, except the number of lamarckian genetic algorithm runs was set to 100; other parameters were considered as their default values. in all docking studies, ligand was allowed to be flexible.

Results

Showed that the human lf had the highest binding energy (-37.1 kcal/mol) among other studied farm animals. the second highest binding energy belonged to cattle lf (-25.6 kcal/mol) and the lowest energy belonged to horse lf.

Conclusion

This result indicated that in case of retroviral infections in infants, breast feeding might be a better option in controlling the infection rather that cow’s or other sources of milk. however, experimental evidence needed to validate this hypothesis.

Keywords

Lactoferrin, antivirus, in silico, human, cattle