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Review Article
- Gut Microbes Libraries: A Key Resource for Current Gut Microbiome Research
- Ayyaz Khan, Sura Kim, Seong-Tshool Hong
- Complex microbial communities shape the dynamics of the human gut, influencing digestion, immunity, and overall health. Advances in DNA sequencing, multi-omics technologies, …
- Complex microbial communities shape the dynamics of the human gut, influencing digestion, immunity, and overall health. Advances in DNA sequencing, multi-omics technologies, and data analysis have significantly improved microbiome studies by enhancing taxonomic resolution and controlling false discovery rates. However, a major limitation remains—the lack of a cultured, representative library of human gut microbes. Existing isolate and genome collections are still limited, especially in strain-level diversity, for most microbes in the human gut. Notably, over 70% of species in the Unified Human Gastrointestinal Genome (UHGG) collection lack cultured representatives. This unknown microbial ‘dark matter’ significantly limits our understanding of the functions of the gut microbiome and its host interactions. To advance our knowledge of the gut microbiome through proof-of-concept research that satisfies Koch’s postulates and supports mechanistic investigations, establishing a comprehensive gut microbe library is essential. However, the scarcity of pure gut microbe cultures worldwide makes constructing a comprehensive gut microbe library challenging. Here we discuss the importance of constructing a comprehensive gut microbial library. It outlines key challenges in establishing a gut microbe library, including sample collection, culture media, and long-term storage. Additionally, it explores the potential applications of a comprehensive gut microbe library in microbiome research. - COLLAPSE
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Review Article
- Overview of the Autophagy Pathways Associated with Infection
- Eun-Jin Park, Eun-Kyeong Jo, Seungwha Paik
- Autophagy is a crucial lysosomal process in the eukaryotic cell that enhances antimicrobial defense during infections. This process encompasses several forms, including …
- Autophagy is a crucial lysosomal process in the eukaryotic cell that enhances antimicrobial defense during infections. This process encompasses several forms, including canonical and noncanonical pathways, which contribute to cellular homeostasis and host immunity. In this review, we first provide an overview of the different types of canonical autophagy before delving into the key mechanisms and molecules involved in macroautophagy, the most extensively studied autophagy pathway. A primary focus of this review is the role of autophagy in host defense against infections, with a detailed examination of its involvement at various stages of pathogen invasion and clearance. Two important types of selective autophagy, xenophagy and mitophagy, specifically target intracellular pathogens and damaged mitochondria, respectively. Recent advancements in understanding the molecular regulation of these selective autophagy pathways have demonstrated their effectiveness in degrading diverse bacterial and viral pathogens. The noncanonical autophagy pathway, LC3-associated phagocytosis, also involves distinct molecular responses to combat different pathogens. Additionally, autophagy exhibits intricate crosstalk with immunometabolism, influencing the metabolic landscape of immune cells to enhance host defense. A comprehensive understanding of autophagy pathways emphasized their potential as a therapeutic targets for combating drug-resistant pathogens. Ongoing research in this field holds promise for developing novel strategies to leverage autophagy for improved infectious disease outcomes. - COLLAPSE
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Review Article
- Exploring the Bioactive Properties and Potential Probionts in the Fish Mucosa
- Francis Harry Shone Villaruel Leonora, Christopher Marlowe Arandela Caipang
- Aquaculture systems face significant economic losses and mass mortality events due to disease outbreaks arising from environmental stressors and pathogenic infections. The …
- Aquaculture systems face significant economic losses and mass mortality events due to disease outbreaks arising from environmental stressors and pathogenic infections. The fish mucosal immune system plays a crucial role in maintaining host homeostasis and serves as the primary defense barrier against exogenous pathogens. The mucosal interface, characterized by its dynamic interplay with the external environment, harbors a diverse repertoire of bioactive molecules and commensal microbiota that contribute immensely to host immunity. Early studies on mucosal extracts demonstrated broad-spectrum antimicrobial activity against various bacterial and fungal pathogens, including those relevant to both fish and human health. Subsequent studies have explored additional bioactivities, including antibiofilm, antiparasitic, and anticancer properties. Furthermore, novel biomolecules responsible for these bioactivities have been identified within the mucosa, presenting potential applications in the development of new antimicrobials with innovative modes of action against drug-resistant pathogens. Additionally, emerging studies on mucosal probionts have identified promising candidates for aquaculture applications, following in vitro and in vivo characterization. Given the dynamic and crucial relationship between the mucosa and fish health, further research into this critical interface is essential. - COLLAPSE
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Original Article
- Epidemiological Trends and Environmental Influences on Scrub Typhus in South Korea from 2001 to 2023
- Chaewon Kim, Nam-Hyuk Cho
- Scrub typhus, a mite-borne disease caused by Orientia tsutsugamushi, has shown an increasing incidence in South Korea, with 143,035 cases reported …
- Scrub typhus, a mite-borne disease caused by Orientia tsutsugamushi, has shown an increasing incidence in South Korea, with 143,035 cases reported between 2001 and 2023. This study analyzes trends and environmental factors influencing the dynamics of the disease. The results reveal a significant annual rise in cases, along with a shift toward earlier seasonal onset and a higher incidence in the southern provinces. Incidence was notably higher among elderly women, identifying them as a primary risk group. A positive correlation between climatic factors, including rising temperature and relative humidity, and increased cases suggests that these environmental changes may be contributing to shifts in seasonality and regional distribution. These findings highlights the need for targeted public health measures and continued research to mitigate scrub typhus risks. - COLLAPSE
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Original Article
- Exploring Non-QRDR Mutations in gyrA and gyrB and Their Impact on Quinolone Resistance in Helicobacter pylori
- Dong-Hae Lee, Oanh Dao Thi, Jong-Hun Ha, Jeong-Gyu Choi, Kyu-Min Kim, Minh Phuong Trinh, Won Jun Anh, Kyung-Min Kang, Jin-Sik Park, Jung-Hyun Byun, Woo-Kon Lee, Myung Hwan Jung, Wongwarut Boonyanugomol, Seung-Chul Baik, Hyung-Lyun Kang, Min-Kyoung Shin
- This study investigates the role of mutations in the quinolone resistance-determining regions (QRDR) and beyond in the gyrA and gyrB genes of …
- This study investigates the role of mutations in the quinolone resistance-determining regions (QRDR) and beyond in the gyrA and gyrB genes of Helicobacter pylori, specifically their contributions to quinolone resistance. While QRDR mutations are well-established as key contributors to resistance, the impact mutations outside the QRDR remains less understood. Using clinical isolates from Korean pediatric patients, the study analyzed both QRDR and non-QRDR mutations through natural transformation and molecular docking to assess their effects on resistance and the ciprofloxacin (CIP) binding structure. Mutations were identified in both gyrA and gyrB, with non-QRDR mutations at positions 134, 190, 705, and 709 in gyrA, and 249 and 624 in gyrB. These non-QRDR mutations were not directly linked to quinolone resistance. However, molecular docking analysis of the 91st position in gyrA revealed significant alterations in the CIP binding structure, which were strongly associated with increased resistance. Moreover, the A134V mutation, although outside the QRDR, was found to accelerate the emergence of spontaneous QRDR mutations, suggesting an indirect role in resistance development. These findings underscore the critical importance of QRDR mutations in H. pylori quinolone resistance, with particular emphasis on the mutation at position 91 of gyrA, which significantly alters the CIP binding structure and correlates with increased resistance. The study provides valuable insights into the mechanisms of antibiotic resistance, enhancing the understanding of H. pylori resistance pathways and informing future research toward developing more effective treatment strategies. - COLLAPSE
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Original Article
- A Novel Inhibitor of Acetohydroxyacid Synthase with Pan-antimycobacterial Activity
- Ji-Ae Choi, Jake Whang, Hwa-Jung Kim, Chang-Hwa Song
- Acetohydroxyacid synthase (AHAS), an enzyme found in microorganisms and plants but absent in animals, has emerged as a promising target for the …
- Acetohydroxyacid synthase (AHAS), an enzyme found in microorganisms and plants but absent in animals, has emerged as a promising target for the development of antibacterial drugs. AHAS is the first enzyme in the branched-chain amino acid biosynthesis pathway. Inhibiting AHAS is a compelling strategy, particularly against mycobacteria. Mycobacteria replicate within phagocytes, where amino acid availability is severely restricted, making AHAS inhibitors particularly attractive candidates for combating mycobacterial infections. While Mycobacterium tuberculosis (Mtb) and non-tuberculous mycobacteria (NTM) strains share significant genetic homology, current anti-Mtb drugs are ineffective against NTM disease. Consequently, the development of novel antibiotics capable of effectively inhibiting NTM growth is crucial in the face of increasing global NTM infection. In this present study, we evaluated the antimycobacterial effects of an AHAS-targeted synthetic compound, K13787, which is targeted against AHAS, on M. abscessus. We found that K13787 exhibited an inhibitory effect on the growth of M. abscessus in vitro and in vivo, and it also improved the survival of M. abscessus-infected mice. These findings suggest that the recently identified compound K13787, which targets AHAS, has the potential to serve as a lead compound in the development of novel antimycobacterial agents for the treatment of M. abscessus infection. In summary, the results of this study indicate that various compounds that inhibit AHAS, including K13787, are promising candidates for treatment of NTM infection. - COLLAPSE
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Original Article
- Mast Cells Promote Macrophage Polarization to M1-like Phenotype through a Tryptase-dependent Process
- Kyung-Ah Cho, Jiyun Kwon, Hyeon Ju Kim, So-Youn Woo
- Mast cells (MCs) activate and support macrophage proliferation in inflammatory microenvironments. However, the role of MCs in regulating macrophage polarization under normal …
- Mast cells (MCs) activate and support macrophage proliferation in inflammatory microenvironments. However, the role of MCs in regulating macrophage polarization under normal physiological conditions remains poorly understood. In this study, we used conditioned medium from the human MC line HMC-1 (HMC-1 CM) to examine its effect on macrophage polarization. HMC-1 CM was introduced at various stages: during the initiation of polarization into M1 and M2 phenotypes, after polarization, and to undifferentiated M0 macrophages. Additionally, we investigated the role of MC-derived tryptase in macrophage polarization using a tryptase inhibitor. Our findings show that HMC-1 CM significantly stimulated M1 marker expression in M0 macrophages when applied at the onset of culture. Moreover, HMC-1 CM increased the expression of Tgfb and Il10 in both M0 and M1-like macrophages, an effect that was diminished by the tryptase inhibitor. These results suggest that tryptase derived from MCs plays a crucial role in mediating macrophage polarization. - COLLAPSE
Journal Informaiton
JOURNAL OF BACTERIOLOGY AND VIROLOGY
JOURNAL OF BACTERIOLOGY AND VIROLOGY
The Korean Society for Microbiology and The Korean Society of Virology
대한미생물학회‧대한바이러스학회
Hall 1, Rm. 1103, Korea Science and Technology Center, 22 Teheran-ro 7-gil, Gangnam-gu, Seoul, S.Korea
Tel: +82-02-887-3062 / Fax: +82-02-887-3063 / E-mail: ksm@ksmkorea.org Copyright© The Korean Society for Microbiology and The Korean Society of Virology. Powered by APUB
Tel: +82-02-887-3062 / Fax: +82-02-887-3063 / E-mail: ksm@ksmkorea.org Copyright© The Korean Society for Microbiology and The Korean Society of Virology. Powered by APUB