Use of DNA Probes to Detect Mycobacterium intracellulare and "X" Mycobacteria among Clinical Isolates of Mycobacterium avium Complex

The Mycobacterium avium complex includes two closely related species, Mycobacterium avium and Mycobacterium intracellulare. They are opportunistic pathogens in humans and responsible for severe disease in a wide variety of animals. Yet, little is known about factors involved in their pathogenicity. Here, we identified, purified and characterized adhesins belonging to the heparin-binding hemagglutinin (HBHA) and laminin-binding protein (LBP) family from M. intracellulare ATCC13950 and examined clinical isolates from patients with different pathologies associated with M. intracellulare infection for the presence and conservation of HBHA and LBP. Using a recombinant derivative strain of M. intracellulare ATCC13950 producing green fluorescent protein and luciferase, we found that the addition of heparin inhibited mycobacterial adherence to A549 cells, whereas the addition of laminin enhanced adherence. Both HBHA and LBP were purified by heparin-Sepharose chromatography and their methylation profiles were determined by mass spectrometry. Patients with M. intracellulare infection mounted strong antibody responses to both proteins. By using PCR and immunoblot analyses, we found that both proteins were highly conserved among all 17 examined clinical M. intracellulare isolates from patients with diverse disease manifestations, suggesting a conserved role of these adhesins in M. intracellulare virulence in humans and their potential use as a diagnostic tool.

Download Full-text

Minimum Inhibitory Concentration Distributions for Mycobacterium Avium Complex Clinical Isolates in the Pacific Northwest

10.1164/ajrccm-conference.2020.201.1_meetingabstracts.a6103 ◽

2020 ◽

Author(s):

P. Chen ◽

F.E. Roy ◽

L.C. Strnad ◽

S.A.R. Siegel ◽

K.L. Winthrop

Keyword(s):

Minimum Inhibitory Concentration ◽

Pacific Northwest ◽

Mycobacterium Avium ◽

Mycobacterium Avium Complex ◽

Inhibitory Concentration ◽

Clinical Isolates ◽

The Pacific

Download Full-text

Hospital water filters as a source of Mycobacterium avium complex

Journal of Medical Microbiology ◽

10.1099/jmm.0.022376-0 ◽

2010 ◽

Vol 59 (10) ◽

pp. 1198-1202 ◽

Cited By ~ 21

Author(s):

Joseph O. Falkinham

Keyword(s):

Water Supply ◽

Mycobacterium Avium ◽

Water Samples ◽

Repetitive Sequence ◽

Mycobacterium Avium Complex ◽

Mycobacterium Intracellulare ◽

Fingerprint Pattern ◽

Water Filters ◽

Mycobacterium Malmoense

Bronchoscopes and the filters used for washing them were found to yield high numbers of Mycobacterium avium isolates sharing the same repetitive sequence-based PCR (rep-PCR) fingerprint pattern as M. avium isolates recovered from patient samples collected by bronchoscopy. Water and biofilm samples collected from the bronchoscopy preparation laboratory yielded M. avium, Mycobacterium intracellulare, Mycobacterium malmoense and Mycobacterium gordonae. Several M. avium and M. intracellulare isolates from water samples in the bronchoscopy laboratory had rep-PCR patterns matching those of patient bronchoscopy isolates. Five of the 22 (23 %) M. avium patient bronchoscopy isolates and 42 of the 56 (75 %) M. intracellulare patient bronchoscopy isolates could have been due to contamination from the water supply.

Download Full-text