TABLE 1.

Comparison of fluorescence intensities (mean value of triplicates) and hybridization efficiencies (mean value of triplicates) for one-step FISH and two-step FISH at different temperatures and hybridization times^a

FISH conditions	Fluorescence intensity	SD	FISH efficiency (%)	SD
Std	225.7	1.3	100.0	0.7
50°C, 30 min	205.6	0.8	82.1	1.6
55°C, 30 min	215.1	1.5	91.3	2.7
60°C, 20 min	213.4	0.7	64.7	0.1
60°C, 30 min	215.7	0.8	83.2	1.9
65°C, 20 min	196.2	0.2	86.1	4.1
65°C, 30 min	161.8	0.6	100.1	1.7
70°C, 15 min	199.5	3.5	83.9	4.0
70°C, 20 min	195.4	8.1	94.9	1.9
70°C, 30 min	192.0	11.7	98.3	6.5
75°C, 10 min	201.7	0.6	85.5	0.1
75°C, 20 min	209.9	0.2	91.3	2.7
75°C, 30 min	219.8	2.9	97.1	3.8
20°C, 20 minb	207.2	2.2	73.2	2.8
50°C, 15 minb	212.8	3.2	100.5	0.9
50°C, 20 minb	211.8	2.2	99.5	2.6
50°C, 25 minb	211.0	1.8	80.0	2.2
55°C, 20 minb	198.5	1.4	100.8	3.9

^aData are illustrated in Fig. 3 and 5. The fluorescence intensities of hybridized E. coli cells were normalized to 0.75-μm beads, while the hybridization efficiencies were normalized to the cell counts for the standard conditions (Std) (46°C; 3 h).

^bIndicates pretreatment of sample at 90°C for 5 min.