Table 1.
FRET-peptide substrates utilized for SARS-CoV 3CLpro activity assays
| Donor, fluorophore, or colorimetric label | Quencher | Wavelength (Ex/Em) | P7 | P6 | P5 | P4 | P3 | P2 | P1 | P1′ | P2′ | P3′ | P4′ | P5′ | P6′ | P7′ | References |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
EDANS
|
Dabcyl
|
330–360 nm/490–538 nm | K† | E* T V* |
S S N S† |
A A S A |
T V L† T V |
L L A L L |
Q Q Q Q Q |
S S A S S |
G G V G G |
L F R L F |
A R S R R |
K† K S K† K* |
S M S M |
E* R* |
This work (Chen, Lin et al., 2005; Chen, Wang et al., 2005; Kuo et al., 2004; Shi and Song, 2006; Wu et al., 2004; Wu et al., 2006) (Bacha et al., 2004) (Chen, Chen et al., 2005a; Chen, Chen et al., 2005b; Chen, Gui et al., 2005) (Kao et al., 2004) |
Alexa Fluor 488
|
QSY 7
|
490 nm/535 nm | C* | E | S | A | T | L | Q | S | G | L | A | K† | This work | ||
Alexa Fluor 594
|
QSY 21 
|
595 nm/620 nm | C* | E | S | A | T | L | Q | S | G | L | A | K† | This work | ||
Abz
|
nitrotyrosine
|
320–340 nm/400–440 nm | S* | V | T | L | Q | S | G | Y† | R | This work; (Blanchard et al., 2004; Kaeppler et al., 2005; Lee et al., 2005) | |||||
Abz
|
Dnp
|
320–362 nm/420–425 nm | T* S* |
S* S G |
A A V |
V V T |
L L F |
Q Q Q |
S S G |
G G K |
F F F |
R R K |
K† K† K† |
(Liu et al., 2005a) (Chou et al., 2004; Hsu et al., 2005; Kuang et al., 2005) (Kuang et al., 2005) |
|||
MCA
|
Dnp
|
320 nm/405 nm | A* | V | L | Q | S | G | F | K† | K | (Yang et al., 2005) | |||||
Rhodamine (fluorophore)
|
492 nm/523 nm | A | R | L | Q* | (Graziano et al., 2006) | |||||||||||
pNA (colorimetric label)
|
390 nm | T | S | A | V | L | Q* | (Chen, Wei et al., 2006; Huang et al., 2004; Liu et al., 2005b; Wei et al., 2006) |
*
attachment site of donor, fluorophore, or colorimetric label
†
attachment site of quencher label