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Journal Articles
Whole-Genome Sequencing Reveals the Population Structure and Genetic Diversity of Salmonella Typhimurium ST34 and ST19 Lineages.
Zhen-Xu Zhuo, Yu-Lian Feng, Xi-Wei Zhang, Hao Liu, Fang-Yin Zeng, Xiao-Yan Li
J. Microbiol. 2024;62(10):859-870.   Published online November 4, 2024
DOI: https://doi.org/10.1007/s12275-024-00170-9
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AbstractAbstract
Salmonella Typhimurium is an invasive gastrointestinal pathogen for both humans and animals. To investigate the genetic framework and diversity of S. Typhimurium, a total of 194 S. Typhimurium isolates were collected from patients in a tertiary hospital between 2020 and 2021. Antimicrobial susceptibility testing was used to confirm the resistance phenotype. Whole-genome sequencing and bioinformatics analysis were performed to determine the sequence type, phylogenetic relationships, resistance gene profiles, Salmonella pathogenicity island (SPI) and the diversity of the core and pan genome. The result showed that 57.22% of S. Typhimurium isolates were multidrug resistant and resistance of total isolates to the first-line drug ciprofloxacin was identified in 60.82%. The population structure of S. Typhimurium was categorized into three lineages: ST19 (20.10%, 39/194), ST34-1 (47.42%, 92/194) and ST34-2 (40.65%, 63/194), with the population size exhibiting increasing trends. All lineages harbored variety of fimbrial operons, prophages, SPIs and effectors that contributed to the virulence and long-term infections of S. Typhimurium. Importantly, ST34-1 lineage might potentially be more invasive due to the possession of SPI1-effector gene sopE which was essential for the proliferation, internalization and intracellular presence of S. Typhimurium in hosts. Multiple antimicrobial resistance genes were characteristically distributed across three lineages, especially carbapenem genes only detected in ST34-1&2 lineages. The distinct functional categories of pan genome among three lineages were observed in metabolism, signaling and gene information processing. This study provides a theoretical foundation for the evolved adaptation and genetic diversity of S. Typhimurium ST19 and ST34, among which ST34 lineages with multidrug resistance and potential hypervirulence need to pay more attention to epidemiological surveillance.
Unexpected Requirement of Small Amino Acids at Position 183 for DNA Binding in the Escherichia coli cAMP Receptor Protein.
Marcus Carranza, Amanda Rea, Daisy Pacheco, Christian Montiel, Jin Park, Hwan Youn
J. Microbiol. 2024;62(10):871-882.   Published online September 6, 2024
DOI: https://doi.org/10.1007/s12275-024-00169-2
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AbstractAbstract
The Escherichia coli cAMP receptor protein (CRP) relies on the F-helix, the recognition helix of the helix-turn-helix motif, for DNA binding. The importance of the CRP F-helix in DNA binding is well-established, yet there is little information on the roles of its non-base-contacting residues. Here, we show that a CRP F-helix position occupied by a non-base-contacting residue Val183 bears an unexpected importance in DNA binding. Codon randomization and successive in vivo screening selected six amino acids (alanine, cysteine, glycine, serine, threonine, and valine) at CRP position 183 to be compatible with DNA binding. These amino acids are quite different in their amino acid properties (polar, non-polar, hydrophobicity), but one commonality is that they are all relatively small. Larger amino acid substitutions such as histidine, methionine, and tyrosine were made site-directedly and showed to have no detectable DNA binding, further supporting the requirement of small amino acids at CRP position 183. Bioinformatics analysis revealed that small amino acids (92.15% valine and 7.75% alanine) exclusively occupy the position analogous to CRP Val183 in 1,007 core CRP homologs, consistent with our mutant data. However, in extended CRP homologs comprising 3700 proteins, larger amino acids could also occupy the position analogous to CRP Val183 albeit with low occurrence. Another bioinformatics analysis suggested that large amino acids could be tolerated by compensatory small-sized amino acids at their neighboring positions. A full understanding of the unexpected requirement of small amino acids at CRP position 183 for DNA binding entails the verification of the hypothesized compensatory change(s) in CRP.
FgVAC1 is an Essential Gene Required for Golgi-to-Vacuole Transport and Fungal Development in Fusarium graminearum.
Sieun Kim, Jiyeun Park, You-Kyoung Han, Hokyoung Son
J. Microbiol. 2024;62(8):649-660.   Published online July 30, 2024
DOI: https://doi.org/10.1007/s12275-024-00160-x
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AbstractAbstract
Fusarium graminearum is an important plant pathogen that causes head blight in cereal crops such as wheat, barley, and rice worldwide. In this study, we identified and functionally characterized FgVAC1, an essential gene in F. graminearum that encodes a Rab5 effector involved in membrane tethering functions. The essentiality of FgVAC1 was confirmed through a conditional promoter replacement strategy using the zearalenone-inducible promoter (PZEAR). Cytological analyses revealed that FgVac1 colocalizes with FgRab51 on early endosomes and regulates the proper transport of the vacuolar hydrolase FgCpy1 to the vacuole. Suppression of FgVAC1 led to inhibited vegetative growth, reduced asexual and sexual reproduction, decreased deoxynivalenol (DON) biosynthesis, and diminished pathogenicity. Our findings highlight the significant role of FgVac1 in vacuolar protein sorting, fungal development, and plant infection in F. graminearum.
Deletion of IRC19 Causes Defects in DNA Double-Strand Break Repair Pathways in Saccharomyces cerevisiae.
Ju-Hee Choi, Oyungoo Bayarmagnai, Sung-Ho Bae
J. Microbiol. 2024;62(9):749-758.   Published online July 12, 2024
DOI: https://doi.org/10.1007/s12275-024-00152-x
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AbstractAbstract
DNA double-strand break (DSB) repair is a fundamental cellular process crucial for maintaining genome stability, with homologous recombination and non-homologous end joining as the primary mechanisms, and various alternative pathways such as single-strand annealing (SSA) and microhomology-mediated end joining also playing significant roles under specific conditions. IRC genes were previously identified as part of a group of genes associated with increased levels of Rad52 foci in Saccharomyces cerevisiae. In this study, we investigated the effects of IRC gene mutations on DSB repair, focusing on uncharacterized IRC10, 19, 21, 22, 23, and 24. Gene conversion (GC) assay revealed that irc10Δ, 22Δ, 23Δ, and 24Δ mutants displayed modest increases in GC frequencies, while irc19Δ and irc21Δ mutants exhibited significant reductions. Further investigation revealed that deletion mutations in URA3 were not generated in irc19Δ mutant cells following HO-induced DSBs. Additionally, irc19Δ significantly reduced frequency of SSA, and a synergistic interaction between irc19Δ and rad52Δ was observed in DSB repair via SSA. Assays to determine the choice of DSB repair pathways indicated that Irc19 is necessary for generating both GC and deletion products. Overall, these results suggest a potential role of Irc19 in DSB repair pathways, particularly in end resection process.
Meta-Analysis
Exploring COVID-19 Pandemic Disparities with Transcriptomic Meta-analysis from the Perspective of Personalized Medicine.
Medi Kori, Ceyda Kasavi, Kazim Yalcin Arga
J. Microbiol. 2024;62(9):785-798.   Published online July 9, 2024
DOI: https://doi.org/10.1007/s12275-024-00154-9
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AbstractAbstract
Infection with SARS-CoV2, which is responsible for COVID-19, can lead to differences in disease development, severity and mortality rates depending on gender, age or the presence of certain diseases. Considering that existing studies ignore these differences, this study aims to uncover potential differences attributable to gender, age and source of sampling as well as viral load using bioinformatics and multi-omics approaches. Differential gene expression analyses were used to analyse the phenotypic differences between SARS-CoV-2 patients and controls at the mRNA level. Pathway enrichment analyses were performed at the gene set level to identify the activated pathways corresponding to the differences in the samples. Drug repurposing analysis was performed at the protein level, focusing on host-mediated drug candidates to uncover potential therapeutic differences. Significant differences (i.e. the number of differentially expressed genes and their characteristics) were observed for COVID-19 at the mRNA level depending on the sample source, gender and age of the samples. The results of the pathway enrichment show that SARS-CoV-2 can be combated more effectively in the respiratory tract than in the blood samples. Taking into account the different sample sources and their characteristics, different drug candidates were identified. Evaluating disease prediction, prevention and/or treatment strategies from a personalised perspective is crucial. In this study, we not only evaluated the differences in COVID-19 from a personalised perspective, but also provided valuable data for further experimental and clinical efforts. Our findings could shed light on potential pandemics.
Journal Article
Enterococcus Phage vB_EfaS_HEf13 as an Anti-Biofilm Agent Against Enterococcus faecalis.
Dongwook Lee, Jintaek Im, A Reum Kim, Woohyung Jun, Cheol-Heui Yun, Seung Hyun Han
J. Microbiol. 2024;62(8):683-693.   Published online June 27, 2024
DOI: https://doi.org/10.1007/s12275-024-00150-z
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AbstractAbstract
Enterococcus faecalis is a Gram-positive bacterium that is frequently found in the periapical lesion of patients with apical periodontitis. Its biofilm formation in root canal is closely related to the development of refractory apical periodontitis by providing increased resistance to endodontic treatments. Phage therapy has recently been considered as an efficient therapeutic strategy in controlling various periodontal pathogens. We previously demonstrated the bactericidal capacities of Enterococcus phage vB_EfaS_HEf13 (phage HEf13) against clinically-isolated E. faecalis strains. Here, we investigated whether phage HEf13 affects biofilm formation and pre-formed biofilm of clinically-isolated E. faecalis, and its combinatory effect with endodontic treatments, including chlorhexidine (CHX) and penicillin. The phage HEf13 inhibited biofilm formation and disrupted pre-formed biofilms of E. faecalis in a dose- and time-dependent manner. Interestingly, phage HEf13 destroyed E. faecalis biofilm exopolysaccharide (EPS), which is known to be a major component of bacterial biofilm. Furthermore, combined treatment of phage HEf13 with CHX or penicillin more potently inhibited biofilm formation and disrupted pre-formed biofilm than either treatment alone. Confocal laser scanning microscopic examination demonstrated that these additive effects of the combination treatments on disruption of pre-formed biofilm are mediated by relatively enhanced reduction in thickness distribution and biomass of biofilm. Collectively, our results suggest that the effect of phage HEf13 on E. faecalis biofilm is mediated by its EPS-degrading property, and its combination with endodontic treatments more potently suppresses E. faecalis biofilm, implying that phage HEf13 has potential to be used as a combination therapy against E. faecalis infections.
Review
The Role of Extracellular Vesicles in Pandemic Viral Infections.
Woosung Shim, Anjae Lee, Jung-Hyun Lee
J. Microbiol. 2024;62(6):419-427.   Published online June 25, 2024
DOI: https://doi.org/10.1007/s12275-024-00144-x
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AbstractAbstract
Extracellular vesicles (EVs), of diverse origin and content, are membranous structures secreted by a broad range of cell types. Recent advances in molecular biology have highlighted the pivotal role of EVs in mediating intercellular communication, facilitated by their ability to transport a diverse range of biomolecules, including proteins, lipids, DNA, RNA and metabolites. A striking feature of EVs is their ability to exert dual effects during viral infections, involving both proviral and antiviral effects. This review explores the dual roles of EVs, particularly in the context of pandemic viruses such as HIV-1 and SARS-CoV-2. On the one hand, EVs can enhance viral replication and exacerbate pathogenesis by transferring viral components to susceptible cells. On the other hand, they have intrinsic antiviral properties, including activation of immune responses and direct inhibition of viral infection. By exploring these contrasting functions, our review emphasizes the complexity of EV-mediated interactions in viral pathogenesis and highlights their potential as targets for therapeutic intervention. The insights obtained from investigating EVs in the context of HIV-1 and SARS-CoV-2 provide a deeper understanding of viral mechanisms and pathologies, and offer a new perspective on managing and mitigating the impact of these global health challenges.
Journal Articles
Identification of avaC from Human Gut Microbial Isolates that Converts 5AVA to 2-Piperidone.
Qiudi Zhou, Lihui Feng
J. Microbiol. 2024;62(5):367-379.   Published online June 17, 2024
DOI: https://doi.org/10.1007/s12275-024-00141-0
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AbstractAbstract
2-piperidone is a crucial industrial raw material of high-value nylon-5 and nylon-6,5. Currently, a major bottleneck in the biosynthesis of 2-piperidone is the identification of highly efficient 2-piperidone synthases. In this study, we aimed to identify specific strains among 51 human gut bacterial strains capable of producing 2-piperidone and to elucidate its synthetic mechanism. Our findings revealed that four gut bacterial strains, namely Collinsella aerofaciens LFYP39, Collinsella intestinalis LFYP54, Clostridium bolteae LFYP116, and Clostridium hathewayi LFYP18, could produce 2-piperidone from 5-aminovaleric acid (5AVA). Additionally, we observed that 2-piperidone could be synthesized from proline through cross-feeding between Clostridium difficile LFYP43 and one of the four 2-piperidone producing strains, respectively. To identify the enzyme responsible for catalyzing the conversion of 5AVA to 2-piperidone, we utilized a gain-of-function library and identified avaC (5-aminovaleric acid cyclase) in C. intestinalis LFYP54. Moreover, homologous genes of avaC were validated in the other three bacterial strains. Notably, avaC were found to be widely distributed among environmental bacteria. Overall, our research delineated the gut bacterial strains and genes involved in 2-piperidone production, holding promise for enhancing the efficiency of industrial biosynthesis of this compound.
Tubulysin Production by the Dead Cells of Archangium gephyra KYC5002.
Seohui Park, Chaehyeon Park, Yujin Ka, Kyungyun Cho
J. Microbiol. 2024;62(6):463-471.   Published online June 13, 2024
DOI: https://doi.org/10.1007/s12275-024-00130-3
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AbstractAbstract
Archangium gephyra KYC5002 produces tubulysins during the death phase. In this study, we aimed to determine whether dead cells produce tubulysins. Cells were cultured for three days until the verge of the death phase, disrupted via ultrasonication, incubated for 2 h, and examined for tubulysin production. Non-disrupted cells produced 0.14 mg/L of tubulysin A and 0.11 mg/L of tubulysin B. Notably, tubulysin A production was increased by 4.4-fold to 0.62 mg/L and that of tubulysin B was increased by 6.7-fold to 0.74 mg/L in the disrupted cells. The same increase in tubulysin production was observed when the cells were killed by adding hydrogen peroxide. However, when the enzymes were inactivated via heat treatment of the cultures at 65 °C for 30 min, no significant increase in tubulysin production due to cell death was observed. Reverse transcription-quantitative polymerase chain reaction analysis of tubB mRNA revealed that the expression levels of tubulysin biosynthetic enzyme genes increased during the death phase compared to those during the vegetative growth phase. Our findings suggest that A. gephyra produces biosynthetic enzymes and subsequently uses them for tubulysin production in the cell death phase or during cell lysis by predators.
Licochalcone A Protects Vaginal Epithelial Cells Against Candida albicans Infection Via the TLR4/NF-κB Signaling Pathway.
Wei Li, Yujun Yin, Taoqiong Li, Yiqun Wang, Wenyin Shi
J. Microbiol. 2024;62(7):525-533.   Published online May 31, 2024
DOI: https://doi.org/10.1007/s12275-024-00134-z
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AbstractAbstract
Vulvovaginal candidiasis (VVC) is a prevalent condition affecting a significant portion of women worldwide. Licochalcone A (LA), a natural compound with diverse biological activities, holds promise as a protective agent against Candida albicans (C. albicans) infection. This study aims to investigate the potential of LA to safeguard vaginal epithelial cells (VECs) from C. albicans infection and elucidate the underlying molecular mechanisms. To simulate VVC in vitro, VK2-E6E7 cells were infected with C. albicans. Candida albicans biofilm formation, C. albicans adhesion to VK2-E6E7 cells, and C. albicans-induced cell damage and inflammatory responses were assessed by XTT reduction assay, fluorescence assay, LDH assay, and ELISA. CCK-8 assay was performed to evaluate the cytotoxic effects of LA on VK2-E6E7 cells. Western blotting assay was performed to detect protein expression. LA dose-dependently hindered C. albicans biofilm formation and adhesion to VK2-E6E7 cells. Furthermore, LA mitigated cell damage, inhibited the Bax/Bcl-2 ratio, and attenuated the secretion of pro-inflammatory cytokines in C. albicans-induced VK2-E6E7 cells. The investigation into LA's impact on the Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) pathway revealed that LA downregulated TLR4 expression and inhibited NF-κB activation in C. albicans-infected VK2-E6E7 cells. Furthermore, TLR4 overexpression partially abated LA-mediated protection, further highlighting the role of the TLR4/NF-κB pathway. LA holds the potential to safeguard VECs against C. albicans infection, potentially offering therapeutic avenues for VVC management.
Review
Reverse Zoonotic Transmission of SARS-CoV-2 and Monkeypox Virus: A Comprehensive Review.
Chiranjib Chakraborty, Manojit Bhattacharya, Md Aminul Islam, Hatem Zayed, Elijah Ige Ohimain, Sang-Soo Lee, Prosun Bhattacharya, Kuldeep Dhama
J. Microbiol. 2024;62(5):337-354.   Published online May 23, 2024
DOI: https://doi.org/10.1007/s12275-024-00138-9
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AbstractAbstract
Reverse zoonosis reveals the process of transmission of a pathogen through the human-animal interface and the spillback of the zoonotic pathogen. In this article, we methodically demonstrate various aspects of reverse zoonosis, with a comprehensive discussion of SARS-CoV-2 and MPXV reverse zoonosis. First, different components of reverse zoonosis, such as humans, different pathogens, and numerous animals (poultry, livestock, pets, wild animals, and zoo animals), have been demonstrated. Second, it explains the present status of reverse zoonosis with different pathogens during previous occurrences of various outbreaks, epidemics, and pandemics. Here, we present 25 examples from literature. Third, using several examples, we comprehensively illustrate the present status of the reverse zoonosis of SARS-CoV-2 and MPXV. Here, we have provided 17 examples of SARS-CoV-2 reverse zoonosis and two examples of MPXV reverse zoonosis. Fourth, we have described two significant aspects of reverse zoonosis: understanding the fundamental aspects of spillback and awareness. These two aspects are required to prevent reverse zoonosis from the current infection with two significant viruses. Finally, the One Health approach was discussed vividly, where we urge scientists from different areas to work collaboratively to solve the issue of reverse zoonosis.
Journal Articles
Genetically Engineered CLDN18.2 CAR-T Cells Expressing Synthetic PD1/CD28 Fusion Receptors Produced Using a Lentiviral Vector.
Heon Ju Lee, Seo Jin Hwang, Eun Hee Jeong, Mi Hee Chang
J. Microbiol. 2024;62(7):555-568.   Published online May 3, 2024
DOI: https://doi.org/10.1007/s12275-024-00133-0
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AbstractAbstract
This study aimed to develop synthetic Claudin18.2 (CLDN18.2) chimeric antigen receptor (CAR)-T (CAR-T) cells as a treatment for advanced gastric cancer using lentiviral vector genetic engineering technology that targets the CLDN18.2 antigen and simultaneously overcomes the immunosuppressive environment caused by programmed cell death protein 1 (PD-1). Synthetic CAR T cells are a promising approach in cancer immunotherapy but face many challenges in solid tumors. One of the major problems is immunosuppression caused by PD-1. CLDN18.2, a gastric-specific membrane protein, is considered a potential therapeutic target for gastric and other cancers. In our study, CLDN18.2 CAR was a second-generation CAR with inducible T-cell costimulatory (CD278), and CLDN18.2-PD1/CD28 CAR was a third-generation CAR, wherein the synthetic PD1/CD28 chimeric-switch receptor (CSR) was added to the second-generation CAR. In vitro, we detected the secretion levels of different cytokines and the killing ability of CAR-T cells. We found that the secretion of cytokines such as interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) secreted by three types of CAR-T cells was increased, and the killing ability against CLDN18.2-positive GC cells was enhanced. In vivo, we established a xenograft GC model and observed the antitumor effects and off-target toxicity of CAR-T cells. These results support that synthetic anti-CLDN18.2 CAR-T cells have antitumor effect and anti-CLDN18.2-PD1/CD28 CAR could provide a promising design strategy to improve the efficacy of CAR-T cells in advanced gastric cancer.
Effects of Light and Dark Conditions on the Transcriptome of Aging Cultures of Candidatus Puniceispirillum marinum IMCC1322.
Ji Hyen Lee, Hyun-Myung Oh
J. Microbiol. 2024;62(4):297-314.   Published online April 25, 2024
DOI: https://doi.org/10.1007/s12275-024-00125-0
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AbstractAbstract
To elucidate the function of proteorhodopsin in Candidatus Puniceispirillum marinum strain IMCC1322, a cultivated representative of SAR116, we produced RNA-seq data under laboratory conditions. We examined the transcriptomes of six different cultures, including sets of expression changes under constant dark (DD), constant light (LL), and diel-cycled (LD; 14 h light: 10 h dark) conditions at the exponential and stationary/death phases. Prepared mRNA extracted from the six samples was analyzed on the Solexa Genome Analyzer with 36 cycles. Differentially expressed genes on the IMCC1322 genome were distinguished as four clusters by K-mean clustering and each CDS (n = 2546) was annotated based on the KEGG BRITE hierarchy. Cluster 0 (n = 1573) covered most constitutive genes including proteorhodopsin, retinoids, and glycolysis/TCA cycle. Cluster 1 genes (n = 754) were upregulated in stationary/death phase under constant dark conditions and included genes associated with bacterial defense, membrane transporters, nitrogen metabolism, and senescence signaling. Cluster 2 genes (n = 197) demonstrated upregulation in exponential phase cultures and included genes involved in genes for oxidative phosphorylation, translation factors, and transcription machinery. Cluster 3 (n = 22) contained light-stimulated upregulated genes expressed under stationary/phases. Stringent response genes belonged to cluster 2, but affected genes spanned various cellular processes such as amino acids, nucleotides, translation, transcription, glycolysis, fatty acids, and cell wall components. The coordinated expression of antagonistic stringent genes, including mazG, ppx/gppA, and spoT/relA may provide insight into the controlled cultural response observed between constant light and constant dark conditions in IMCC1322 cultures, regardless of cell numbers and biomass.
Syntaxin17 Restores Lysosomal Function and Inhibits Pyroptosis Caused by Acinetobacter baumannii.
Zhiyuan An, Wenyi Ding
J. Microbiol. 2024;62(4):315-325.   Published online March 7, 2024
DOI: https://doi.org/10.1007/s12275-024-00109-0
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AbstractAbstract
Acinetobacter baumannii (A. baumannii) causes autophagy flux disorder by degrading STX17, resulting in a serious inflammatory response. It remains unclear whether STX17 can alter the inflammatory response process by controlling autolysosome function. This study aimed to explore the role of STX17 in the regulation of pyroptosis induced by A. baumannii. Our findings indicate that overexpression of STX17 enhances autophagosome degradation, increases LAMP1 expression, reduces Cathepsin B release, and improves lysosomal function. Conversely, knockdown of STX17 suppresses autophagosome degradation, reduces LAMP1 expression, augments Cathepsin B release, and accelerates lysosomal dysfunction. In instances of A. baumannii infection, overexpression of STX17 was found to improve lysosomal function and reduce the expression of mature of GSDMD and IL-1β, along with the release of LDH, thus inhibiting pyroptosis caused by A. baumannii. Conversely, knockdown of STX17 led to increased lysosomal dysfunction and further enhanced the expression of mature of GSDMD and IL-1β, and increased the release of LDH, exacerbating pyroptosis induced by A. baumannii. These findings suggest that STX17 regulates pyroptosis induced by A. baumannii by modulating lysosomal function.
Saxibacter everestensis gen. nov., sp. nov., A Novel Member of the Family Brevibacteriaceae, Isolated from the North Slope of Mount Everest.
Mao Tian, Shiyu Wu, Wei Zhang, Gaosen Zhang, Xue Yu, Yujie Wu, Puchao Jia, Binglin Zhang, Tuo Chen, Guangxiu Liu
J. Microbiol. 2024;62(4):277-284.   Published online March 6, 2024
DOI: https://doi.org/10.1007/s12275-024-00108-1
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AbstractAbstract
We isolated and analyzed a novel, Gram-stain-positive, aerobic, rod-shaped, non-motile actinobacterium, designated as strain ZFBP1038(T), from rock sampled on the north slope of Mount Everest. The growth requirements of this strain were 10-37 °C, pH 4-10, and 0-6% (w/v) NaCl. The sole respiratory quinone was MK-9, and the major fatty acids were anteiso-C(15:0) and iso-C(17:0). Peptidoglycan containing meso-diaminopimelic acid, ribose, and glucose were the major cell wall sugars, while polar lipids included diphosphatidyl glycerol, phosphatidyl glycerol, an unidentified phospholipid, and an unidentified glycolipid. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZFBP1038(T) has the highest similarity with Spelaeicoccus albus DSM 26341( T) (96.02%). ZFBP1038(T) formed a distinct monophyletic clade within the family Brevibacteriaceae and was distantly related to the genus Spelaeicoccus. The G + C content of strain ZFBP1038(T) was 63.65 mol% and the genome size was 4.05 Mb. Digital DNA-DNA hybridization, average nucleotide identity, and average amino acid identity values between the genomes of strain ZFBP1038(T) and representative reference strains were 19.3-25.2, 68.0-71.0, and 52.8-60.1%, respectively. Phylogenetic, phenotypic, and chemotaxonomic characteristics as well as comparative genome analyses suggested that strain ZFBP1038(T) represents a novel species of a new genus, for which the name Saxibacter gen. nov., sp. nov. was assigned with the type strain Saxibacter everestensis ZFBP1038(T) (= EE 014( T) = GDMCC 1.3024( T) = JCM 35335( T)).

Journal of Microbiology : Journal of Microbiology
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