Detection and Identification of Mycobacterium Using SecA

This invention relates to a method of detecting a wide variety of Mycobacterium and Nocardia species in a sample. The method involves hybridizing an amplified Mycobacterium/Nocardia genus-specific secA nucleic acid to a Mycobacterium/Nocardia species-specific secA probe oligonucleotide, wherein the amplification utilizes at least two Mycobacterium/Nocardia genus-specific primers, and detecting hybridization of the Mycobacterium/Nocardia–specific secA nucleic acid. The Mycobacterium/Nocardia genus-specific primers bind within a conserved region of the nucleic acid sequence encoding a Mycobacterium/Nocardia bi-genus-specific secA protein, wherein the conserved region is in the 5’ half of the Mycobacterium/Nocardia secA gene and includes a substrate specificity domain.

The approach for detection of Mycobacterium/Nocardia species in clinical materials could potentially be used as a universal system for detection of any member of the genus Mycobacterium and the genus Nocardia and identification at the species or complex level. The system currently identifies all mycobacteria tested to date. With a few modifications, we believe it will also detect all Nocardia species of clinical significance. Contrary to commercial methods based on 16S rRNA and ITS, the SecA method will detect both Mycobacterium and Nocardia species. The region targeted has sufficient sequence variation for discrimination at the species or complex level.

Based on the information available to date, the SecA approach could be potentially used to replace acid-fast smears (AFB) and modified acid-fast smears, could provide definitive detection and identification of a large variety of Mycobacterium and Nocardia species present in clinical materials, and could be used as a single confirmation and species identification system for suspected positive Mycobacterium or Nocardia cultures. The invention also contemplates devices, including arrays, and kits for detecting Mycobacterium or Nocardia species in a sample.

This technology is related to Dr. Fischer’s other technology, E-278-1999/0, "Multiplex Hybridization System for the Identification of Pathogenic Mycobacterium and Method of Use" (published in the Federal Register on September 7, 2002, 65 FR 54288). The distinguishing feature in the current invention that makes it a vast improvement over E-278-1999/0 is the ability to detect all 29 Mycobacterium species tested to date and potentially all Nocardia species in a clinical sample.


Steven Fischer (CC)  ➽ more inventions...

Adrian Zelazny ()  ➽ more inventions...

Intellectual Property:
US Application No. PCT/US2005/06609

Licensing Contact:
Admin. Licensing Specialist (ALS),

OTT Reference No: E-238-2003/0
Updated: Jun 1, 2005