New putative animal reservoirs of SARS-CoV-2 in Italian fauna: A bioinformatic approach

Abstract

SARS-CoV-2 is a virus belonging to the betacoronavirus family, causing fatal respiratory disease in humans, which became pandemic in 2020. Italy is one of the most affected countries by COVID-19, particularly in the northern regions. Several studies consider COVID-19 a zoonotic disease and, since Italy is the repository of a high biodiversity, SARS-CoV-2 infection in animals can be considered as a reservoir of the virus or favor the spreading between animals and humans. In this work, we analyzed the amino acid sequences of ACE2 protein of the most common domestic and wild animals present in Italy. Among the latter, we focused on ACE2 of the Chiroptera species present in Italy to identify the primary reservoir in this region. First, we reproduced in silico the Chiroptera ACE2/viral spike (S) protein interactions on the human ACE2/SARS-CoV-2 S complex model and identified the critical residues for the binding. In silico molecular docking of ACE2 belonging to Chiroptera vs SARS-CoV-2 S protein pointed to Rhinolophus ferrumequinum as a bat living in Italy, that may be a potential primary reservoir of the virus. On the other hand, a sequence similarity search on ACE2 of domestic and wild animals living in Italy pointed to domestic (horses, cats, cattle and sheep) and wild (European rabbits and grizzly bears) animal species as potential SARS-CoV-2 secondary reservoirs. Molecular docking of ACE2 belonging to these species vs S protein of Bat coronavirus (Bt-CoV/Rp3/2004) suggests that the primary reservoir Rhinolophus ferrumequinum may infect the secondary reservoirs, domestic and worldwide animals living in Italy, determining a specific risk of SARS-CoV-2 infection.

No Detection of SARS-CoV-2 in Animals Exposed to Infected Keepers: Results of a COVID-19 Surveillance Program

“…A comprehensive phylogenetic analysis coupled with critical site comparison of the ACE2 receptor showed that several species, including civet, swine, pangolin, cat, cow, buffalo, goat, sheep and pigeon, may be susceptible to SARS-CoV-2 and serve as intermediate hosts [ 16 ]. Similar findings have been reported by other authors who have analyzed the amino acid sequences of the ACE2 receptor of a number of wild and domestic animals and concluded that horses, cats, cattle, sheep, European rabbits and grizzly bears may serve as potential SARS-CoV-2 secondary reservoirs [ 17 ]. Experimental studies have confirmed that inoculation of SARS-CoV-2 can cause infection of rabbits [ 18 ].…”

Investigation of the Role of Healthy and Sick Equids in the COVID-19 Pandemic through Serological and Molecular Testing

“…The role of equids in the COVID-19 pandemic has remained poorly investigated. Horses are potentially susceptible to SARS-CoV-2 based on the binding affinity and stability between ACE-2 and the receptor-binding domain of the S protein [ 8 , 9 ]. Considering the large number of equids globally and the direct or indirect contact these animals have with humans, information pertaining to their susceptibility to SARS-CoV-2 and their role in virus transmission is needed.…”

Assessment of GO-Based Protein Interaction Affinities in the Large-Scale Human–Coronavirus Family Interactome

“…A search for ACE2 sequence similarities in domestic and wild animals in Italy revealed domestic (horses, cats, cattle, and sheep) and wild (European rabbits and grizzly bears) animal species as potential SARS-CoV-2 secondary reservoirs. Molecular docking of these species’ ACE2 against the S protein of the Bat coronavirus (Bt-CoV/Rp3/2004) suggests that the primary reservoir Rhinolophus ferrumequinum may infect secondary reservoirs, domestic and animals living in Italy [ 81 ].…”