TABLE 1.

Concentrations of total bacterial cells and CTC-positive bacterial cells and mean CTC fluorescence (emission at >630 nm) for samples stored at 4°C or in liquid nitrogen

Day	Refrigerator storage (4°C)			Liquid N2 storage
	Cell concn (107 cells ml−1)		Mean CTC fluores-cence (RFU)	Cell concn (107 cells ml−1)		Mean CTC fluores-cence (RFU)
	Total bacteriaa	CTC-positive bacteria		Total bacteriaa	CTC-positive bacteria
0	2.65 (0.16)b	2.23 (0.11)	8.26 (0.62)	2.45 (0.07)	2.08 (0.21)	8.13 (0.36)
1	2.73 (0.15)	2.36 (0.08)	9.76 (0.12)	2.80 (0.17)	2.08 (0.17)	9.73 (0.10)
4	2.83 (0.06)	2.37 (0.14)	9.80 (0.04)	2.98 (0.10)	2.41 (0.11)	9.49 (0.07)
7	2.39 (0.38)	2.40 (0.14)	9.26 (0.07)	2.10 (0.36)	2.45 (0.30)	9.19 (0.07)
14	2.30 (0.18)	2.34 (0.12)	9.14 (0.07)	2.63 (0.11)	2.43 (0.15)	9.44 (0.04)
28	2.63 (0.10)	2.23 (0.28)	10.07 (0.10)	2.50 (0.15)	2.37 (0.15)	9.77 (0.10)

^aThe initial concentration before CTC was added was 3.62 × 10⁷ ± 0.13 × 10⁷ cells ml⁻¹ (n = 3). 

^bMean (standard deviation) based on three samples.