title: Detection of anthrax toxin genetic sequences by the solid phase oligo-probes.
abstract: OBJECTIVE
  There is an urgent need to detect a rapid field-based test to detect anthrax. We have developed a rapid, highly sensitive DNA-based method to detect the anthrax toxin lethal factor gene located in pXO1, which is necessary for the pathogenicity of Bacillus anthracis.
  
  
  METHODS
  We have adopted the enzyme-linked immunosorbent assay (ELISA) so that instead of capturing antibodies we capture the DNA of the target sequence by a rapid oligo-based hybridization and then detect the captured DNA with another oligoprobe that binds to a different motif of the captured DNA sequences at a dissimilar location. We chose anthrax lethal factor endopeptidase sequences located in pXO1 and used complementary oligoprobe, conjugated with biotin, to detect the captured anthrax specific sequence by the streptavidin-peroxidase-based colorimetric assay.
  
  
  RESULTS
  Our system can detect picomoles (pMoles) of anthrax (approximately 33 spores of anthrax) and is >1000 times more sensitive than the current ELISA, which has a detection range of 0.1 to 1.0 ng/mL. False positive results can be minimized when various parameters and the colour development steps are optimized.
  
  
  CONCLUSIONS
  Our results suggest that this assay can be adapted for the rapid detection of minuscule amounts of the anthrax spores that are aerosolized in the case of a bioterrorism attack. This detection system does not require polymerase chain reaction (PCR) step and can be more specific than the antibody method. This method can also detect genetically engineered anthrax. Since, the antibody method is so specific to the protein epitope that bioengineered versions of anthrax may not be detected.
authors: South Carolina Center for Biotechnology, Claflin University, Orangeburg, SC 29115, USA.
authors: K C
authors: KC
authors: Addanki
authors: M
authors: M
authors: Sheraz
authors: K
authors: K
authors: Knight
authors: K
authors: K
authors: Williams
authors: D G
authors: DG
authors: Pace
authors: O
authors: O
authors: Bagasra
mesh_terms: D000881:Anthrax / Q000175:diagnosis*; D000942:Antigens, Bacterial / Q000235:genetics*; D001427:Bacterial Toxins / Q000235:genetics*; D003124:Colorimetry / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D015345:Oligonucleotide Probes / Q000235:genetics*; D012680:Sensitivity and Specificity
chemical_list: D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D015345:Oligonucleotide Probes; C030325:anthrax toxin