TABLE 4.

Effects of analogs on the growth of H. volcanii and H. halobium in liquid medium

Analog added to medium	Concn (mM)	Growth (%)a
		H. volcanii	H. halobium
2-Fluoroadenine	1	<5	<5
2,6-Diaminopurine	1	67	71
6-Mercaptopurine	1	<5	33
6-Thioguanine	1	<5	<5
6-Methylpurine	1	<5	<5
8-Azaadenine	1	36	48
8-Azaguanine	1	<5	<5
8-Azaxanthine	1	100	100
8-Azahypoxanthine	1	<5	<5
2-Fluoroadenosine	0.5	16	34
6-Mercaptopurine riboside	0.5	15	83
6-Mercaptoguanosine	0.5	<5	67
8-Mercaptoguanosine	0.5	<5	83
Purine riboside	0.5	67	90
Psicofuranine	0.5	80	83
Trimethoprim	0.03	<2	100
Sulfathiazole	0.03	<10	100
Mycophenolic acid	0.3	100	100

^aExponentially growing cells were diluted to an OD₄₃₆ of 0.02 to 0.03 and were supplemented with the indicated analogs. Growth was monitored in control cultures grown in the absence of analogs until an OD₄₃₆ of 1.2 was reached (defined as 100% growth). The growth yields (OD₄₃₆) of the analog-supplemented cultures were determined and expressed as percentages of the control cultures.