The peptidases involved in the infection and replication of CoVs.

Table 1: The peptidases involved in the infection and replication of CoVs.

Peptidase	Catalytic type	Function	Origin	CoV	Reference
Chymotrypsin-like peptidase 3CL^pro(M^pro)	Cysteine	Polyprotein processing	viral	All	Reviewed in [37]
PLP PL1^pro	Cysteine	Polyprotein processing, immune system evasion	viral	α-CoV (NL63, 229E), β -CoV (HKU1, OC43)	Reviewed in [49]
PLP PL2^pro	Cysteine	Polyprotein processing, immune system evasion	viral	All	Reviewed in [49]
ACE2	Metallo (Zinc)	Receptor	Host	SARS, NL63	Reviewed in [14,60]
Aminopeptidase N	Metallo (Zinc)	Receptor	Host	229E	[65]
DPP4	Serine	Receptor	Host	MERS	[12]
TMPRSS2	Serine	Spike protein proteolytic activation	Host	SARS, MERS, 229E, OC43, HKU1, SARS-CoV-2	[59,73,75,77,78,79,80]
Cathepsins L and B	Cysteine	Spike protein proteolytic activation	Host	SARS, MERS	[81,85]

ACE2: Angiotensin-Converting Enzyme 2; α-CoV: Alphacoronavirus; β-CoV: Betacoronavirus; CoV: Coronavirus; DPP4: Dipeptidyl Peptidase 4; PLP: Papain-Like Peptidase; MERS: Middle East Respiratory Syndrome; M^pro: Main Peptidase; SARS: Severe Acute Respiratory Syndrome; SARS-CoV-2: Severe Acute Respiratory Syndrome Coronavirus 2; TMPRSS2: Transmembrane Peptidase/Serine Subfamily Member 2. Source: [31].