Science - USA (2021-12-10)

1356 10 DECEMBER 2021¥VOL 374 ISSUE 6573 science.orgSCIENCE

Delta (B.1.617.2)

one RBD-up conformation 2

S2

FPPR

NTD

RBD

CTD1

630 loop CTD2

C

Kappa (B.1.617.1)

closed conformation

S2

FPPR

NTD

RBD

CTD1

630 loop CTD2

D Kappa (B.1.617.1)

one RBD-up conformation 1

S2

FPPR

NTD

RBD

CTD1

630 loop CTD2

E

Delta (B.1.617.2)

closed conformation

S2

FPPR

NTD RBD

CTD1

630 loop

A

F157del

R158del

L452R

E156G

D950N

T19R

G142D

D614G

T478K L452R

T478K

P681R

Delta (B.1.617.2)

one RBD-up conformation 1

S2

FPPR

NTD

RBD

CTD1

CTD2

CTD2

630 loop

B

Kappa (B.1.617.1)

one RBD-up conformation 2

F

Delta (B.1.617.2)

closed conformation

I

630 loop FPPR

RBD down

RBD down

RBD down

a

bc

a

c

a

c

b b

617

644

823

862

617

644 823

862

617

823 644

862

Gamma (B.1.1.28)

one RBD-up conformation 1

G

S2

FPPR

NTD RBD

CTD1

630 loop

N501Y E484K

K417T

D138Y

P26S D614G

T20N

L18F

CTD2

S2

FPPR

NTD

RBD

CTD1

CTD2

630 loop

Gamma (B.1.1.28)

one RBD-up conformation 2

H

S2

FPPR

NTD

RBD

CTD1

630 loop CTD2

E154K

Q218H

L452R

E484Q

D614G

H1101D

V1264L

P681R

L452R

E484Q

R190S

H655Y

V1176F

T1027I

Fig. 3. Cryo-EM structures of full-length SARS-CoV-2 S proteins from the
Delta, Kappa, and Gamma variants.(AtoC) The structures of the closed
prefusion conformation and two one-RBD-up conformations of the Delta S trimer
are shown in the ribbon diagrams, with one protomer colored as follows: NTD in
blue, RBD in cyan, CTD1 in green, CTD2 in light green, S2 in light blue, the
630 loop in red, and the FPPR in magenta. (DtoF) The structures of the closed
prefusion conformation and two one-RBD-up conformation of the Kappa S
trimer are shown in the ribbon diagrams, with the same color scheme as in (A).

(G) and (H) The structures of the two one-RBD-up conformations of the Gamma

S trimer are shown in the ribbon diagrams with the same color scheme as in

(A). All mutations in the three variants, as compared to the original virus (D614),

are highlighted in the sphere model. (I) Structures in the Delta closed trimer

of segments (residues 617 to 644) containing the 630 loop (red) and segments

(residues 823 to 862) containing the FPPR (magenta) from each of the

three protomers (A), (B), and (C). The position of each RBD is indicated.

Dashed lines indicate gaps in the chain trace (disordered loops).

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