Investigating the presence of key amino acid residues for human ace-2 receptor binding domain (rbd) of sars-cov-2-like coronaviruses isolated from bats in east coast malaysia

An abstract of the research paper submitted to the Faculty of Veterinary Medicine, Universiti Malaysia Kelantan, in partial fulfilment of the course DVT55204 – Research Project.

Covid-19 is a recently emerging form of severe acute respiratory syndrome (SARS) caused by SARS-Coronavirus-2 (SARS-CoV-2) which was first reported in Wuhan, China in December 2019. Bats are natural reservoirs for coronaviruses, and bat coronaviruses have been highlighted as some strains of SARS-like coronavirus (SARSL-CoV-2) carried by bats are almost identical to human SARS-CoV-2 at the genome level, especially the spike protein. Some strains of these bat coronaviruses are highly similar to human SARS-CoV-2 and are able to use the same receptor as SARS-CoV-2 to mediate cell entry. Early last year, five SARS-CoV-2-like viruses were isolated from bats in East Coast Malaysia (four from Sekayu, Terengganu and one from Gunung Reng, Kelantan). Angiotensin-converting enzyme 2 (ACE-2) has been identified as the important receptor of SARS-CoV and SARS-CoV-2 to enter human cells. The interaction between the S1 protein of the virus, particularly amino acid fragment 318-510, with the human ACE-2 receptor is the critical determinant of coronavirus host range and cross-species transmission. This study aimed to investigate the presence of key amino acid residues for human ACE-2 on the RBD of the spike protein of these bat coronaviruses. Reverse transcription polymerase chain reaction (RT-PCR), and sequencing of the PCR products were used to investigate the presence of the ACE-2 RBD. From the results obtained in this experiment, it was determined that coronaviruses isolated from bats in East Coast Malaysia can utilise human ACE-2 receptors to infect human cells and thus may become a public health concern in the future.

Keywords: SARS-CoV-2-like coronaviruses, ACE-2 receptors, Receptor Binding Domain (RBD), bat coronaviruses, human transmission