Redesigned and chemically-modified hammerhead ribozymes with improved activity and serum stability

BMC Chemical Biology

Table 2 Cleavage Rate constants for cleavage of S-30 by Chemically Modified Mrz-12/12.

Miniribozyme (Mrz-12/12)	C₃	U₄	U₇	C_15.2	3' end	Cleavage rate constant (min^-1)	Relative Stability
A	-	-	-	-	-	4.2 ± 0.3	1
B	F	NH₂	NH₂	F	-	0.30 ± 0.05	-
C	-	NH₂	NH₂	-	-	0.18 ± 0.01	-
D	-	NH₂	-	-	-	0.30 ± 0.03	-
E	-	-	NH₂	-	-	7.7 ± 0.8	-
F	-	dT	-	-	-	0.014 ± 0.005	-
G	-	dU	-	-	-	0.024 ± 0.007	-
H	-	OMe	-	-	-	0.01 ± 0.007	-
I	-	ps	-	-	-	3.9 ± 0.06	-
J	OMe	ps	OMe	OMe	psps	7.3 ± 0.7	1400
K	OMe	NH₂	OMe	OMe	-	0.6 ± 0.1	8600
Rz-12/12-L	-	NH₂	-	-	-	0.05 ± 0.009	-

Cleavage conditions; 37°C, pH 7.6, 10 mM MgCl_2. [Rz] = 1 μM, [S30] = 5 nM. (- = unmodified, ie 2'OH). F = 2'-fluoro, NH₂ = 2'-amino, dT = 2'-deoxythymidine, dU = 2'-deoxyuridine, OMe = 2'-O-methyl, ps = 3' phosphorothioate linkage. Stability is defined as the time required in 10% human serum to degrade 75% of full-length ribozyme, relative to unmodified miniribozyme A.