The mutation induced by space conditions in Escherichia coli

Table 3 The occurrence of Lac⁺ phenotype among Arg⁺ revertants

Sample	Group	Total No. of Arg+ reversion	No. of Lac+	Lac+/Arg+ (%)
Boarding sample	Group I	60	25	41.7
	Group II	139	52	37.4
	Group III	384	376	97.9
Ground control	A(1)	36	14	38.9
	B(2)	39	27	69.2

A⁽¹⁾ and B⁽²⁾ are the same with that in Table 2.