Characteristics of sars-coV-2 and covid-19

687
671
H S M S S L
-
-
-
- R S
V
N
Q R S
683
671
Q T Q T N S
-
-
-
- R S
V
S
S Q A
683
635
-
- - - N S P
-
A A R -
V
G
T N S
645
662
H T V S S L
-
-
-
- R S
T
S
Q K S
674
1
100
200
300
400
500
600
700
800
900
1,000
1,100
1,200 1,273
SARS-CoV-2
BJ01
RaTG13
GX pangolin
GD pangolin
RmYN02
Bat WIV1
S1 subunit
S2 subunit
NTD
SP
FP
RBM
HR2
CP
TM
HR1
NTD
SP
FP
RBM
HR2
CP
TM
HR1
1 13
1 13
292 306
527
770 788
894
966
1,145 1,195 1,219
424
494
667 668
1,255
305 319
541
685
788 806
912
984
1,163 1,213 1,237
437
508
686
1,273
RBD
Host
445
L
Y(442)
L
L
L
S(429)
S(443)
486
F
L(472)
L
L
F
–
F(473)
493
Q
N(479)
Y
E
Q
S(453)
N(480)
494
S
D(480)
R
R
S
T(454)
D(481)
501
N
T(487)
N
T
N
V(461)
N(488)
Human 
Human 
Rhinolophus affinis
Pangolin
Pangolin
Rhinolophus malayanus
Rhinolophus sinicus
SARS-CoV-2
SARS-CoV
RaTG13
GX pangolin
GD pangolin
RmYN02
Bat WIV1
Important residues in RBD contact with ACE2
N501 T487
D480 S494
Q493
N479 L445
Y442
L472
F486
c
d
Human ACE2
SARS-CoV-2 RBD
SARS-CoV RBD
Fig. 3 | 
Key differences in the spike protein of SARS-CoV-2 and related 
coronaviruses. a | Schematic diagram of the spike (S) protein of severe acute 
respiratory syndrome coronavirus (SARS- CoV) and SARS- CoV-2. The residue 
numbers of each region correspond to their positions in the S proteins of 
SARS- CoV and SARS- CoV-2. The dark blue blocks represent insertions in the 
S protein. The insertions at amino acids 675–691 of the SARS- CoV-2 S protein 
are shown in an enlargement at the bottom right and aligned with those of 
other coronaviruses in the same region. 
b | Alignment of the receptor- binding 
domain (RBD) in SARS- CoV-2, SARS- CoV BJ01, RaTG13, pangolin coronavirus 
reported from Guangdong, China (GD pangolin), pangolin coronavirus 
reported from Guangxi, China (GX pangolin) and bat SARS- related 
coronavirus (SARSr- CoV) WIV1. The receptor- binding motif (RBM) is shown 
in purple, and the five key residues that contact angiotensin- converting 
enzyme 2 (ACE2) directly are highlighted in green. 
c | Five critical residues in 
the RBD of SARS- CoV-2 and other viruses. 
d | Comparison of the structure
of SARS- CoV-2 and SARS- CoV RBD complexed with human ACE2 (hACE2); 
SARS- CoV-2 RBM in purple, SARS- CoV RBM in yellow and hACE2 in green). 
Five critical residues that are involved in the RBM–ACE2 binding are shown. 
The Protein Data Bank codes are 2AJF for SARS- CoV RBD–hACE2 and 6VW1 
for SARS- CoV-2 RBD–hACE2. The GenBank entries are AY278488 for 
SARS- CoV BJ01, MN996532 for the bat SARSr- CoV RaTG13, MT121216 and 
MT072864 for the GD pangolin and GX pangolin coronaviruses, respectively, 
and KF367457 for the bat SARSr- CoV WIV1. CP, cytoplasmic domain;
FP, fusion peptide; HR1, heptad repeat 1; HR2, heptad repeat 2; NTD, 
N- terminal domain; SP, signal peptide; TM, transmembrane domain. Parts