Skip to main content

Table 2 Inability of RT-qPCR to detect invA mRNA in RNA extracts not treated with DNase I

From: Comparison of commercial RNA extraction kits for preparation of DNA-free total RNA from Salmonella cells

RNA extraction kit

Manufacturer

invA mRNA copies/rxn

RT-qPCR [Cq]a

invA DNA copies/rxn

qPCR [Cq]b

invA mRNA presence

(Cq qPCR - Cq RT-qPCR)c

RiboPure-Bacteria

Ambion

(1.9 ± 1.6) × 106 [25.5 ± 1.8]

(1.8 ± 1.8) × 106 [24.8 ± 1.4]

-0. 7 (Negative)

PureLink RNA Mini

Invitrogen

(1.2 ± 0.5) × 108 [18.8 ± 0.6]

(1.5 ± 0.8) × 108 [18.5 ± 0.7]

-0.3 (Negative)

RNeasy Mini

QIAGEN

(7.9 ± 2.2) × 107 [19.3 ± 0.4]

(1.1 ± 0.3) × 108 [18.9 ± 0.4]

-0.4 (Negative)

MasterPure RNA Purification

EPICENTRE Biotechnologies

(5.8 ± 0.8) × 108 [16.4 ± 0.2]

(8.8 ± 0.9) × 108 [15.9 ± 0.2]

-0.3 (Negative)

UltraClean Microbial RNA Isolation

MoBio

(2.2 ± 0.6) × 108 [17.8 ± 0.4]

(3.4 ± 0.8) × 108 [17.3 ± 0.3]

-0.5 (Negative)

  1. rxn, reaction.
  2. ainvA mRNA copies per reaction are mean values of 6 determinations ± standard deviations.
  3. binvA DNA copies per reaction are mean values of 6 determinations ± standard deviations.
  4. c- If <4 is negative or inconclusive for invA mRNA presence due to DNA contamination.
  5. Detection limit of the invA qRT-PCR and invA qPCR are 40 and 10 copies per reaction, respectively [7]