Biodegradation and Removal of PAHs by Bacillus velezensis Isolated from Fermented Food

( Omme Fatema Sultana ),( Saebim Lee ),( Hoonhee Seo ),( Hafij Al Mahmud ),( Sukyung Kim ),( Ho-Yeon Song ),( Mijung Kim ),( Ho-yeon Song ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.7

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment. They are highly toxigenic and carcinogenic. Probiotic bacteria isolated from fermented foods were tested to check their ability to degrade and/or detoxify PAHs. Five probiotic bacteria with distinct morphologies were isolated from a mixture of 26 fermented foods co-cultured with benzo(a)pyrene (BaP) containing Bushnell Haas minimal broth. Among them, B. velezensis (PMC10) significantly reduced the abundance of BaP in the broth. PMC10 completely degraded BaP presented at a lower concentration in broth culture. B. velezensis also showed a clear zone of degradation on a BaP-coated Bushnell Haas agar plate. Gene expression profiling showed significant increases of PAH ring-hydroxylating dioxygenases and 4-hydroxybenzoate 3-monooxygenase genes in B. velezensis in response to BaP treatment. In addtion, both live and heat-killed B. velezensis removed BaP and naphthalene (Nap) from phosphate buffer solution. Live B. velezensis did not show any cytotoxicity to macrophage or human dermal fibroblast cells. Live-cell and cell-free supernatant of B. velezensis showed potential anti-inflammatory effects. Cell-free supernatant and extract of B. velezensis also showed free radical scavenging effects. These results highlight the prospective ability of B. velezensis to biodegrade and remove toxic PAHs from the human body and suggest that the biodegradation of BaP might be regulated by ring-hydroxylating dioxygenase-initiated metabolic pathway.

Changes in the Microbiome of Vaginal Fluid after Menopause in Korean Women

( Sukyung Kim ),( Hoonhee Seo ),( Md Abdur Rahim ),( Saebim Lee ),( Yun-sook Kim ),( Ho-yeon Song ) 한국미생물 · 생명공학회 2021 Journal of microbiology and biotechnology Vol.31 No.11

Various microorganisms reside in the human vagina; the vaginal microbiome is closely linked to both vaginal and general health, and for this reason, microbiome studies of the vagina are an area of research. In this study, we analyzed the vaginal microbiome of women before and after menopause to further increase our understanding of the vaginal microbiome and its contribution to general health. We did a 16s rRNA gene-based metagenomic analysis on the vaginal fluids of 11 premenopausal and 19 postmenopausal women in Korea. We confirmed that the taxonomic composition was significantly different between the two groups. In postmenopausal women, species richness was significantly decreased, but species diversity was significantly increased. In particular, among the taxonomic components corresponding to all taxon ranks of the vaginal microbiome, a reduction in Lactobacillus taxa after menopause contributed the most to the difference between the two groups. In addition, we confirmed through metabolic analysis that the lactic-acid concentration was also decreased in the vaginal fluid of women after menopause. Our findings on the correlation between menopause and the microbiome could help diagnose menopause and enhance the prevention and treatment diseases related to menopause.

Anti-Tuberculosis Activity of Pediococcus acidilactici Isolated from Young Radish Kimchi against Mycobacterium tuberculosis

( Youjin Yoon ),( Hoonhee Seo ),( Sukyung Kim ),( Youngkyoung Lee ),( Md Abdur Rahim ),( Saebim Lee ),( Ho-yeon Song ) 한국미생물 · 생명공학회 2021 Journal of microbiology and biotechnology Vol.31 No.12

Tuberculosis is a highly contagious disease caused by Mycobacterium tuberculosis. It affects about 10 million people each year and is still one of the leading causes of death worldwide. About 2 to 3 billion people (equivalent to 1 in 3 people in the world) are infected with latent tuberculosis. Moreover, as the number of multidrug-resistant, extensively drug-resistant, and totally drug-resistant strains of M. tuberculosis continues to increase, there is an urgent need to develop new anti-tuberculosis drugs that are different from existing drugs to combat antibiotic-resistant M. tuberculosis. Against this background, we aimed to develop new anti-tuberculosis drugs using probiotics. Here, we report the anti-tuberculosis effect of Pediococcus acidilactici PMC202 isolated from young radish kimchi, a traditional Korean fermented food. Under coculture conditions, PMC202 inhibited the growth of M. tuberculosis. In addition, PMC202 inhibited the growth of drug-sensitive and -resistant M. tuberculosis- infected macrophages at a concentration that did not show cytotoxicity and showed a synergistic effect with isoniazid. In a 2-week, repeated oral administration toxicity study using mice, PMC202 did not cause weight change or specific clinical symptoms. Furthermore, the results of 16S rRNA-based metagenomics analysis confirmed that dysbiosis was not induced in bronchoalveolar lavage fluid after oral administration of PMC202. The anti-tuberculosis effect of PMC202 was found to be related to the reduction of nitric oxide. Our findings indicate that PMC202 could be used as an anti-tuberculosis drug candidate with the potential to replace current chemical-based drugs. However, more extensive toxicity, mechanism of action, and animal efficacy studies with clinical trials are needed.

Efficacy of Lactobacillus fermentum Isolated from the Vagina of a Healthy Woman against Carbapenem-Resistant Klebsiella Infections In Vivo

( Hanieh Tajdozian ),( Hoonhee Seo ),( Sukyung Kim ),( Md Abdur Rahim ),( Saebim Lee ),( Ho-yeon Song ) 한국미생물 · 생명공학회 2021 Journal of microbiology and biotechnology Vol.31 No.10

Carbapenem-resistant Enterobacteriaceae (CRE) that produce Klebsiella pneumoniae carbapenemase are increasingly reported worldwide and have become more and more resistant to nearly all antibiotics during the past decade. The emergence of K. pneumoniae strains with decreased susceptibility to carbapenems, which are used as a last resort treatment option, is a significant threat to hospitalized patients worldwide as K. pneumoniae infection is responsible for a high mortality rate in the elderly and immunodeficient individuals. This study used Lactobacillus fermentum as a candidate probiotic for treating CRE-related infections and investigated its effectiveness. We treated mice with L. fermentum originating from the vaginal fluid of a healthy Korean woman and evaluated the Lactobacilli’s efficacy in preventive, treatment, nonestablishment, and colonization mouse model experiments. Compared to the control, pre-treatment with L. fermentum significantly reduced body weight loss in the mouse models, and all mice survived until the end of the study. The oral administration of L. fermentum after carbapenemresistant Klebsiella (CRK) infection decreased mortality and illness severity during a 2-week observation period and showed that it affects other strains of CRK bacteria. Also, the number of Klebsiella bacteria was decreased to below 5.5 log10 CFU/ml following oral administration of L. fermentum in the colonization model. These findings demonstrate L. fermentum’s antibacterial activity and its potential to treat CRE infection in the future.

In Vitro and In Vivo Anti-Clostridioides difficile Effect of a Probiotic Bacillus amyloliquefaciens Strain

( Md Imtiazul Islam ),( Hoonhee Seo ),( Asma Redwan ),( Sukyung Kim ),( Saebim Lee ),( Mashuk Siddiquee ),( Ho-yeon Song ) 한국미생물 · 생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.1

Clostridioides difficile infection (CDI) is a significant cause of hospital-acquired and antibiotic-mediated intestinal diseases and is a growing global public health concern. Overuse of antibiotics and their effect on normal intestinal flora has increased the incidence and severity of infections. Thus, the development of new, effective, and safe treatment options is a high priority. Here, we report a new probiotic strain, Bacillus amyloliquefaciens (BA PMC-80), and its in vitro/in vivo anti-C. difficile effect as a prospective novel candidate for replacing conventional antibiotics. BA PMC-80 showed a significant anti-C. difficile effect in coculture assay, and its cell-free supernatant (CFS) also exhibited a considerable anti-C. difficile effect with an 89.06 μg/ml 50% minimal inhibitory concentration (MIC) in broth microdilution assay. The CFS was stable and equally functional under different pHs, heat, and proteinase treatments. It also exhibited a high sensitivity against current antibiotics and no toxicity in subchronic toxicity testing in hamsters. Finally, BA PMC-80 showed a moderate effect in a hamster CDI model with reduced infection severity and delayed death. However, further studies are required to optimize the treatment condition of the hamster CDI model for better efficacy and identify the antimicrobial compound produced by BA PMC-80.

Activity of Lactobacillus crispatus isolated from vaginal microbiota against Mycobacterium tuberculosis

이영경,Seo Hoonhee,Kim Sukyung,Rahim MD Abdur,Yoon Youjin,Jung Jehee,Lee Saebim,Ryu Chang Beom,Song Ho-Yeon 한국미생물학회 2021 The journal of microbiology Vol.59 No.11

Tuberculosis, an infectious disease, is caused by Mycobacterium tuberculosis. It remains a significant public health issue around the globe, causing about 1.8 million deaths every year. Drug-resistant M. tuberculosis, including multi-drug-resistant (MDR), extremely-drug-resistant (XDR), and totally drugresistant (TDR) M. tuberculosis, continues to be a threat to public health. In the case of antibiotic-resistant tuberculosis, the treatment effect of conventional antibiotics is low. Side effects caused by high doses over a long period are causing severe problems. To overcome these problems, there is an urgent need to develop a new anti-tuberculosis drug that is different from the existing compound-based antibiotics. Probiotics are defined as live microorganisms conferring health benefits. They can be potential therapeutic agents in this context as the effectiveness of probiotics against different infectious diseases has been well established. Here, we report that Lactobacillus crispatus PMC201 shows a promising effect on tuberculosis isolated from vaginal fluids of healthy Korean women. Lactobacillus crispatus PMC201 reduced M. tuberculosis H37Rv under co-culture conditions in broth and reduced M. tuberculosis H37Rv and XDR M. tuberculosis in macrophages. Lactobacillus crispatus PMC201 was not toxic to a guinea pig model and did not induce dysbiosis in a human intestinal microbial ecosystem simulator. Taken together, these results indicate that L. crispatus PMC201 can be a promising alternative drug candidate in the current tuberculosis drug regime. Further study is warranted to assess the in vivo efficacy and confirm the mode of action of L. crispatus PMC201.