NeoCoV, a koronavirusa strain related to MERS-CoV found in bats (NeoCoV is not a new variant of SARS-CoV-2, the human koronavirusa strain responsible for COVID-19 pandemic) has been reported to be the first case of a MERS-CoV variant using ACE2. NeoCoV has potential of human emergence with both high fatality and transmission rate.
NeoCoV je srodan soj MERS-CoV koji koristi šišmiš ACE 2 receptore za njegov ulazak i infekciju u stanice šišmiša. Međutim, sojevi od Mers-titio koristi DPP4 receptore za ulazak u stanicu. Važno je napomenuti da NeoCoV nije nova varijanta SARS-COV 2 koji je izazvao svjetsku pandemiju od njenog nastanka u studenom 2019.
This article shows that NeoCoV and its close relative PDF-2180-CoV is able to efficiently bind to ACE 2 receptors in bat, but bind less favourably to human ACE 2 receptors. Studies using cryo-electron microscopy revealed a distinct virus-ACE 2 binding surface in case of binding of NeoCoV and PDF-2180-CoV to ACE 2 receptors. A molecular determinant implicates Asp 338 residue, that prevents NeoCoV from binding to human ACE 2 receptor. In addition, a T510F mutation in the receptor binding motif of NeoCoV causes it to efficiently bind human ACE 2 receptor.
Given the high fatality rate of 35% associated with MERS-CoV related virusi derived from Beta CoV lineage, the NeoCoV could pose a potential threat to emergence of a high transmissible strain of NeoCoV and PDF-2180-CoV (upon gaining the T510F mutation due to antigenic drift) that can cause infection and mortality in humans, far worse than the current pandemic. Antigenic drift refers to random genetic mutacije što je izazvalo promjene u protein strukturu, čime se mijenja sposobnost proteina da se veže na određeni receptor. Osim toga, infekcija uzrokovana mutacijom T510F NeoCoV nije mogla biti unakrsno neutralizirana antitijelima usmjerenim na SARS-CoV-2 ili MERS-CoV.
The entire global community hopes that the mutation in NeoCoV and PDF-2180-CoV that causes it to efficiently bind to human ACE 2 receptor, remains a laboratory study to understand the virulence of these virusi, and it doesn’t become a case of zoonotic transmission from bats to humans, creating another worldwide chaos.
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Izvor:
Yan H., dr. 2022. Bliski rođaci MERS-CoV kod šišmiša koriste ACE2 kao svoje funkcionalne receptore. Prettisak bioRxiv. Objavljeno 25. siječnja 2022. DOI: https://doi.org/10.1101/2022.01.24.477490
