Table 2.

Maintenance of plasmids in P. furiosus^a

Passage	No. of cells
	pJFW018		pJFW027		pJFW019
	+ura	−ura	+ura	−ura	+ura	−ura
1	187	256	190	194	73	112
2	132	217	97	203	54	268
3	112	232	132	143	11	138
4	146	117	154	165	6	83
5	87	276	100	113	0	77
6	138	197	151	201	0	104
7	144	263	111	122	0	91
8	118	242	87	131	0	94
9	93	213	114	218	0	97
10	107	183	112	169	0	87

^aTransformants containing each plasmid were serially passaged in liquid medium with uracil (+ura) or without uracil (−ura). Following each passage, a diluted culture was plated onto selective medium to determine the number of prototrophic cells remaining.