International Scholarly Research Notices

Research Article

Identification of pBC218/pBC210 Genes of Bacillus cereus G9241 in Five Florida Soils Using qPCR

Table 3

The limit of detection of assay for ORF 0047 using genomic and plasmid DNA extracts from B. cereus G9241 (CBD 1056).


DNA concentration (ng/L)		CT^a value average (range)
Genomic	Plasmid	Genomic DNA	Plasmid DNA

647.1	17.5	24.68 (24.63–24.73)	14.15 (14.14–14.18)
64.71	1.75	24.12 (24.04–24.18)	15.23 (15.12–15.36)
6.471	0.175	27.00 (26.95–27.03)	17.24 (17.64–17.89)
0.6471	1.75 × 10⁻³	30.71 (30.57–31.02)	20.82 (20.69–21.95)
0.06471	1.75 × 10⁻⁴	36.35 (35.89–36.58)	24.96 (24.80–25.11)
6.471 × 10⁻³	1.75 × 10⁻⁵	38.97 (38.92–40.00)	28.41 (28.35–28.54)
6.471 × 10⁻⁴	1.75 × 10⁻⁶	Undetected^b	32.63 (31.58–33.77)
6.471 × 10⁻⁵	1.75 × 10⁻⁷	Undetected	34.87 (34.51–35.29)
6.471 × 10⁻⁶	1.75 × 10⁻⁸	Undetected	37.03 (36.48–39.57)
6.471 × 10⁻⁷	1.75 × 10⁻⁹	Undetected	Undetected

The genomic DNA was extracted using the boil preparation method, while plasmid DNA was extracted as previously described [17]. The starting DNA concentration of CBD 1057 was 687.3 ng/L and 16.5 ng/L for genomic and plasmid extractions, respectively. The CT averages and ranges for ORF 0067 and ORF 0072 were similar (±1.2 and ±1.4, respectively, for genomic DNA) to the values above for both CBD 1056 and 1057. Thus, these were not included in this table. CT values ≥40 are regarded as negatives. The limit of detection was then determined to be the prior dilution.
^a“CT” denotes cycle threshold value.
^b“Undetected” denotes that no CT value was given for the sample tested.