16S and 23S rRNA Gene Mutation Independent Multidrug Resistance of Non-Tuberculous Mycobacteria Isolated from South Korean Soil

Abstract

Non-tuberculous mycobacteria (NTM) are ubiquitous microorganisms that have the potential to cause disease in both humans and animals. Recently, NTM infections have rapidly increased in South Korea, especially in urbanized areas. However, the distribution of species and the antibiotic resistance profile of NTM in environmental sources have not yet been investigated. Therefore, we analyzed the distribution of species and the antibiotic resistance profile of NTM in soil within urban areas of South Korea. A total of 132 isolates of NTM were isolated from soil samples from 1 municipal animal shelter and 4 urban area parks. Among the 132 isolates, 105 isolates were identified as slowly growing mycobacteria (SGM) and 27 isolates as rapidly growing mycobacteria (RGM) based on the sequences of the rpoB and hsp65 genes. The antibiotic resistance patterns of NTM isolates differed from species to species. Additionally, a mutation in the rrs gene found in this study was not associated with aminoglycoside resistance. In conclusion, our results showed that NTM isolates from South Korean soil exhibit multidrug resistance to streptomycin, amikacin, azithromycin, ethambutol, isoniazid, and imipenem. These results suggest that NTM may pose a public threat.

Genetic Diversity of Non-Tuberculous Mycobacteria among Symptomatic TB negative Patients in Kenya

“…Other countries with similar findings include China [39]- [41], Russia [42], America [43], [44], various countries in Europe [45] and Africa [11], [20], [46]- [48]. The high infectivity rate of MAC species could be attributed to their seemingly abundant nature and distribution in different environmental sources such as water and soil, consequently increasing its ease of spread and infection to humans [20], [49]. MAC has been highly associated with NTM-PD [50]; however, it remains unclear how its infectivity relates to NTM-PD [51].…”

Comparison of Macrophage Immune Responses and Metabolic Reprogramming in Smooth and Rough Variant Infections of Mycobacterium mucogenicum

“…In a similar manner, electron microscopy confirmed that the surface of Mmuc -R was more wrinkled and rough, while the surfaces of the strains Mmuc -ATCC and Mmuc -S were less wrinkled. Previous studies on the colony morphotypes of NTMs, including M. abscessus , have shown that rough morphotypes lacking GPLs induce a greater inflammatory response and more virulence than smooth morphotypes [ 5 , 13 ].…”

“…In addition, most NTMs that cause infections are challenging to treat and worsen the patient’s prognosis because they are resistant to the first-line drug for tuberculosis [ 4 ]. According to their growth rate, NTMs that grow on the media within or after 7 days are defined as rapidly growing mycobacteria (RGM) and slowly growing mycobacteria (SGM), respectively [ 5 ]. Of these, Mycobacterium mucogenicum ( Mmuc ) belongs to the RGM group [ 6 ].…”

Mycobacterium intracellulare induces a Th17 immune response via M1-like macrophage polarization in canine peripheral blood mononuclear cells

“…In addition, NTM infection mostly occurs by exposure to environmental sources because of the ubiquitous nature. Our previous study showed that MAC accounted for most of NTM isolated from soil that collected in animal shelter and parks 5 . Therefore, it is important to understand the pathogenicity of MAC in dogs not only for treatment and diagnosis but also to prevent potential zoonotic transmission between humans and dogs.…”