TABLE 1.

Specific infectivities and plaque sizes of 4-base deletion constructs

Construct	Bases deleteda	Infectivity (PFU/μg RNA)	Mean diam of plaques (mm) ± SD
M1	167-170
M2	159-162
M3b	140-143	1.2 × 101
M4	129-132
M5	123-126
M6	120-123	2.7 × 105	3.0 ± 0.7
M7	118-121	2.0 × 105	2.8 ± 0.5
M8	116-119	3.6 × 105	3.1 ± 0.6
M9	106-109	9.0 × 105	4.1 ± 0.5
M10	92-95	2.1 × 105	2.9 ± 0.8
M11	79-82	1.8 × 106	3.8 ± 0.6
M12	57-60	1.3 × 105	4.4 ± 0.5
M13	48-51	1.5 × 105	4.9 ± 0.6
M14	33-36	1.9 × 105	4.3 ± 0.4
M15	26-29	4.3 × 105	4.6 ± 0.9
CP7-388		1.2 × 106	4.9 ± 0.8

^aNumbers correspond to those in Fig. 1.

^bEmergence of pseudorevertants.