Journal of Microbiology

Journal Articles

Antimicrobial Efficacy of Allium cepa and Zingiber officinale Against the Milk‑Borne Pathogen Listeria monocytogenes: Abirami Arasu , Nagaram Prabha , Durga Devi , Praveen Kumar Issac , Khaloud Mohammed Alarjani , Dunia A. Al Farraj , Reem A. Aljeidi , Dina S. Hussein , Magesh Mohan , Jehad Zuhair Tayyeb , Ajay Guru , Jesu Arockiaraj; J. Microbiol. 2023;61(11):993-1011. Published online December 4, 2023; DOI: https://doi.org/10.1007/s12275-023-00086-w

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Abstract: Listeria monocytogenes is an important food-borne pathogen that causes listeriosis and has a high case fatality rate despite its low incidence. Medicinal plants and their secondary metabolites have been identified as potential antibacterial substances, serving as replacements for synthetic chemical compounds. The present studies emphasize two significant medicinal plants, Allium cepa and Zingiber officinale, and their efficacy against L. monocytogenes. Firstly, a bacterial isolate was obtained from milk and identified through morphology and biochemical reactions. The species of the isolate were further confirmed through 16S rRNA analysis. Furthermore, polar solvents such as methanol and ethanol were used for the extraction of secondary metabolites from A. cepa and Z. officinale. Crude phytochemical components were identified using phytochemical tests, FTIR, and GC–MS. Moreover, the antibacterial activity of the crude extract and its various concentrations were tested against L. monocytogenes. Among all, A. cepa in methanolic extracts showed significant inhibitory activity. Since, the A. cepa for methanolic crude extract was used to perform autography to assess its bactericidal activity. Subsequently, molecular docking was performed to determine the specific compound inhibition. The docking results revealed that four compounds displayed strong binding affinity with the virulence factor Listeriolysin-O of L. monocytogenes. Based on the above results, it can be concluded that the medicinal plant A. cepa has potential antibacterial effects against L. monocytogenes, particularly targeting its virulence.

Vaginal Microbiome Dysbiosis is Associated with the Different Cervical Disease Status: Yingying Ma , Yanpeng Li , Yanmei Liu , Le Cao , Xiao Han , Shujun Gao , Chiyu Zhang; J. Microbiol. 2023;61(4):423-432. Published online April 3, 2023; DOI: https://doi.org/10.1007/s12275-023-00039-3

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3 Citations

Abstract: Vaginal microbiome composition was demonstrated to be associated with cervical disease. The colonization characteristics of vaginal microbes and their association with the different cervical disease status, especially cervical cancer (CC), are rarely investigated. In this cross-sectional study, we characterized the vaginal microbiome of women with different status of cervical diseases, including 22 NV + (normal tissue with HPV infection), low-grade squamous intraepithelial lesion (LSIL, n = 45), high-grade squamous intraepithelial lesion (HSIL, n = 36) and CC (n = 27) using bacterial 16S DNA sequencing. Thirty HPV-negative women with normal tissue were used as the control group. We found that higher diversity of microbiome with gradual depletion of Lactobacillus, especially L. crispatus, was associated with the severity of cervical disease. High-risk HPV16 infection was associated with higher microbiome diversity and depletion of Lactobacillus in high-grade cervical diseases (i.e. HSIL and CC). The CC group was characterized by higher levels of Fannyhessea vaginae, Prevotella, Bacteroides, Finegoldia, Vibrio, Veillonella, Peptostreptococcus, and Dialister. Co-occurrence network analyses showed that negative correlations were exclusively observed between Lactobacillus and other bacteria, and almost all non-Lactobacillus bacteria were positively correlated with each other. In particular, the most diverse and complex co-occurrence network of vaginal bacteria, as well as a complete loss of L. crispatus, was observed in women with CC. Logistic regression model identified HPV16 and Lactobacillus as significant risk and protective factors for CC, respectively. These results suggest that specific Lactobacillus species (e.g. L. crispatus and L. iners) can be used as important markers to target prevention measures prioritizing HPV16-infected women and other hrHPV-infected women for test, vaccination and treat initiatives.

Gamma-glutamyltransferase of Helicobacter pylori alters the proliferation, migration, and pluripotency of mesenchymal stem cells by affecting metabolism and methylation status: Zeyu Wang , Weijun Wang , Huiying Shi , Lingjun Meng , Xin Jiang , Suya Pang , Mengke Fan , Rong Lin; J. Microbiol. 2022;60(6):627-639. Published online April 18, 2022; DOI: https://doi.org/10.1007/s12275-022-1575-4

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6 Citations

Abstract: Virulence factor gamma-glutamyltransferase (GGT) of H. pylori consumes glutamine (Gln) in the stomach to decrease the tricarboxylic acid metabolite alpha-ketoglutarate (α-kg) and alter the downstream regulation of α-kg as well as cellular biological characteristics. Our previous research indicated that under H. pylori infection, mesenchymal stem cells (MSCs) migrated to the stomach and participated in gastric cancer (GC) development either by differentiating into epithelial cells or promoting angiogenesis. However, how MSCs themselves participate in H. pylori-indicated GC remains unclear. Therefore, a GGT knockout H. pylori strain (Hp- KS-1) was constructed, and downstream histone H3K9 and H3K27 methylation and the PI3K/AKT signaling pathway of α-kg were detected using Western blotting. The biological characteristics of MSCs were also examined. An additive α-kg supplement was also added to H. pylori-treated MSCs to investigate alterations in these aspects. Compared to the control and Hp-KS-1 groups, H. pylori-treated MSCs reduced Gln and α-kg, increased H3K9me3 and H3K27me3, activated the PI3K-AKT signaling pathway, and promoted the proliferation, migration, self-renewal, and pluripotency of MSCs. The addition of α-kg rescued the H. pylori-induced alterations. Injection of MSCs to nude mice resulted in the largest tumors in the H. pylori group and significantly reduced tumor sizes in the Hp-KS-1 and α-kg groups. In summary, GGT of H. pylori affected MSCs by interfering with the metabolite α-kg to increase trimethylation of histone H3K9 and H3K27, activating the PI3K/AKT signaling pathway, and promoting proliferation, migration, self-renewal, and pluripotency in tumorigenesis, elucidating the mechanisms of MSCs in GC development.

Alcohol dehydrogenase 1 and NAD(H)-linked methylglyoxal oxidoreductase reciprocally regulate glutathione-dependent enzyme activities in Candida albicans: Sa-Ouk Kang , Min-Kyu Kwak; J. Microbiol. 2021;59(1):76-91. Published online December 23, 2020; DOI: https://doi.org/10.1007/s12275-021-0552-7

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Abstract: Glutathione reductase (Glr1) activity controls cellular glutathione and reactive oxygen species (ROS). We previously demonstrated two predominant methylglyoxal scavengers– NAD(H)-linked methylglyoxal oxidoreductase (Mgd1) and alcohol dehydrogenase 1 (Adh1)–in glutathione-depleted γ- glutamyl cysteinyl synthetase-disrupted Candida albicans. However, experimental evidence for Candida pathophysiology lacking the enzyme activities of Mgd1 and Adh1 on glutathione- dependent redox regulation remains unclear. Herein, we have aimed to demonstrate that glutathione-dependent enzyme activities coupled with cellular ROS changes is regulated by methylglyoxal accumulation in Δmgd1/Δadh1 double disruptants. Δmgd1/Δadh1 showed severe growth defects and G1-phase cell cycle arrest. The observed complementary and reciprocal methylglyoxal-oxidizing and methylglyoxalreducing activities between Δmgd1 and Δadh1 were not always exhibited in Δmgd1/Δadh1. Although intracellular accumulation of methylglyoxal and pyruvate was shown in all disruptants, to a greater or lesser degree, methylglyoxal was particularly accumulated in the Δmgd1/Δadh1 double disruptant. While cellular ROS significantly increased in Δmgd1 and Δadh1 as compared to the wild-type, Δmgd1/Δadh1 underwent a decrease in ROS in contrast to Δadh1. Despite the experimental findings underlining the importance of the undergoing unbalanced redox state of Δmgd1/Δadh1, glutathione- independent antioxidative enzyme activities did not change during proliferation and filamentation. Contrary to the significantly lowered glutathione content and Glr1 enzyme activity, the activity staining-based glutathione peroxidase activities concomitantly increased in this mutant. Additionally, the enhanced GLR1 transcript supported our results in Δmgd1/Δadh1, indicating that deficiencies of both Adh1 and Mgd1 activities stimulate specific glutathione-dependent enzyme activities. This suggests that glutathione-dependent redox regulation is evidently linked to C. albicans pathogenicity under the control of methylglyoxal-scavenging activities.

Retracted Publication

Cryptic prophages in a blaNDM-1-bearing plasmid increase bacterial survival against high NaCl concentration, high and low temperatures, and oxidative and immunological stressors: So Yeon Kim , Kwan Soo Ko; J. Microbiol. 2020;58(6):483-488. Published online March 28, 2020; DOI: https://doi.org/10.1007/s12275-020-9605-6

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Abstract: In this study, we investigated the effect of cryptic prophage regions in a blaNDM-1-bearing plasmid, which was identified in a patient from South Korea, on the survival of bacteria against adverse environmental conditions. First, we conjugated the intact plasmid and plasmids with deleted cryptic prophages into Escherichia coli DH5α. The E. coli transconjugants carrying the plasmid with intact cryptic prophages showed increased survival during treatment with a high concentration of NaCl, high and low temperatures, an oxidative stressor (H2O2), and an immunological stressor (human serum). By contrast, the transconjugants carrying the plasmid with a single-cryptic prophage knockout did not show any change in survival rates. mRNA expression analyses revealed that the genes encoding sigma factor proteins were highly upregulated by the tested stressors and affected the expression of various proteins (antioxidant, cell osmosis-related, heat shock, cold shock, and universal stress proteins) associated with the specific defense against each stress. These findings indicate that a bacterial strain carrying a plasmid with intact carbapenemase gene and cryptic prophage regions exhibited an increased resistance against simulated environmental stresses, and cryptic prophages in the plasmid might contribute to this enhanced stress resistance. Our study indicated that the coselection of antibiotic resistance and resistance to other stresses may help bacteria to increase survival rates against adverse environments and disseminate.

Journal Articles

Methyltransferase of a cell culture-adapted hepatitis E inhibits the MDA5 receptor signaling pathway: Jinjong Myoung , Jeong Yoon Lee , Kang Sang Min; J. Microbiol. 2019;57(12):1126-1131. Published online November 22, 2019; DOI: https://doi.org/10.1007/s12275-019-9478-8

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Abstract: Hepatitis E virus (HEV) is a causative agent of acute hepatitis and jaundice. The number of human infections is approximated to be over 20 million cases per year. The transmission is mainly via the fecal-oral route and contaminated water and food are considered to be a major source of infection. As a mouse model is not available, a recent development of a cell culture-adapted HEV strain (47832c) is considered as a very important tools for molecular analysis of HEV pathogenesis in cells. Previously, we demonstrated that HEV-encoded methyltransferase (MeT) encoded by the 47832c strain inhibits MDA5- and RIG-I-mediated activation of interferon β (IFN-β) promoter. Here, we report that MeT impairs the phosphorylation and activation of interferon regulatory factor 3 and the p65 subunit of NF-κB in a dose-dependent manner. In addition, the MeT encoded by the 47832c, but not that of HEV clinical or field isolates (SAR-55, Mex-14, KC-1, and ZJ-1), displays the inhibitory effect. A deeper understanding of MeTmediated suppression of IFN-β expression would provide basis of the cell culture adaptation of HEV.

Biofilm characterization of Fusarium solani keratitis isolate: increased resistance to antifungals and UV light: Itzel Margarita Córdova-Alcántara , Diana Laura Venegas-Cortés , María Ángeles Martínez-Rivera , Néstor Octavio Pérez , Aida Verónica Rodriguez-Tovar; J. Microbiol. 2019;57(6):485-497. Published online May 27, 2019; DOI: https://doi.org/10.1007/s12275-019-8637-2

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42 Citations

Abstract: Fusarium solani has drawn phytopathogenic, biotechnological, and medical interest. In humans, it is associated with localized infections, such as onychomycosis and keratomycosis, as well as invasive infections in immunocompromised patients. One pathogenicity factor of filamentous fungi is biofilm formation. There is still only scarce information about the in vitro mechanism of the formation and composition of F. solani biofilm. In this work, we describe the biofilm formed by a clinical keratomycosis isolate in terms of its development, composition and susceptibility to different antifungals and ultraviolet light (UV) at different biofilm formation stages. We found five biofilm formation stages using scanning electron microscopy: adherence, germination, hyphal development, maturation, and cell detachment. Using epifluorescence microscopy with specific fluorochromes, it was elucidated that the extracellular matrix consists of carbohydrates, proteins, and extracellular DNA. Specific inhibitors for these molecules showed significant biofilm reductions. The antifungal susceptibility against natamycin, voriconazole, caspofungin, and amphotericin B was evaluated by metabolic activity and crystal violet assay, with the F. solani biofilm preformation to 24 h increased in resistance to natamycin, voriconazole, and caspofungin, while the biofilm preformation to 48 h increased in resistance to amphotericin B. The preformed biofilm at 24 h protected and reduced UV light mortality. F. solani isolate could produce a highly structured extra biofilm; its cellular matrix consists of carbohydrate polymers, proteins, and eDNA. Biofilm confers antifungal resistance and decreases its susceptibility to UV light. The fungal biofilm functions as a survival strategy against antifungals and environmental factors.

Gentic overexpression increases production of hypocrellin A in Shiraia bambusicola S4201: Dan Li , Ning Zhao , Bing-Jing Guo , Xi Lin , Shuang-Lin Chen , Shu-Zhen Yan; J. Microbiol. 2019;57(2):154-162. Published online January 31, 2019; DOI: https://doi.org/10.1007/s12275-019-8259-8

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15 Citations

Abstract: Hypocrellin A (HA) is a perylenequinone (PQ) isolated from Shiraia bambusicola that shows antiviral and antitumor activities, but its application is limited by the low production from wild fruiting body. A gene overexpressing method was expected to augment the production rate of HA in S. bambusicola. However, the application of this molecular biology technology in S. bambusicola was impeded by a low genetic transformation efficiency and little genomic information. To enhance the plasmid transformant ratio, the Polyethylene Glycol-mediated transformation system was established and optimized. The following green fluorescent protein (GFP) analysis showed that the gene fusion expression system we constructed with a GAPDH promoter Pgpd1 and a rapid 2A peptide was successfully expressed in the S. bambusicola S4201 strain. We successfully obtained the HA high-producing strains by overexpressing O-methyltransferase/FAD-dependent monooxygenase gene (mono) and the hydroxylase gene (hyd), which were the essential genes involved in our putative HA biosynthetic pathway. The overexpression of these two genes increased the production of HA by about 200% and 100%, respectively. In general, this study will provide a basis to identify the genes involved in the hypocrellin A biosynthesis. This improved transformation method can also be used in genetic transformation studies of other fungi.

Crystal structure of the inactive state of the receiver domain of Spo0A from Paenisporosarcina sp. TG-14, a psychrophilic bacterium isolated from an Antarctic glacier: Chang Woo Lee , Sun-Ha Park , Sung Gu Lee , Seung Chul Shin , Se Jong Han , Han-Woo Kim , Hyun Ho Park , Sunghwan Kim , Hak Jun Kim , Hyun Park , HaJeung Park , Jun Hyuck Lee; J. Microbiol. 2017;55(6):464-474. Published online March 9, 2017; DOI: https://doi.org/10.1007/s12275-017-6599-9

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Abstract: The two-component phosphorelay system is the most pre-valent mechanism for sensing and transducing environ-mental signals in bacteria. Spore formation, which relies on the two-component phosphorelay system, enables the long- term survival of the glacial bacterium Paenisporosarcina sp. TG-14 in the extreme cold environment. Spo0A is a key re-sponse regulator of the phosphorelay system in the early stage of spore formation. The protein is composed of a regu-latory N-terminal phospho-receiver domain and a DNA- binding C-terminal activator domain. We solved the three- dimensional structure of the unphosphorylated (inactive) form of the receiver domain of Spo0A (PaSpo0A-R) from Paenisporosarcina sp. TG-14. A structural comparison with phosphorylated (active form) Spo0A from Bacillus stearo-thermophilus (BsSpo0A) showed minor notable differences. A molecular dynamics study of a model of the active form and the crystal structures revealed significant differences in the α4 helix and the preceding loop region where phosphorylation occurs. Although an oligomerization study of PaSpo0A-R by analytical ultracentrifugation (AUC) has shown that the protein is in a monomeric state in solution, both crosslinking and crystal-packing analyses indicate the possibility of weak dimer formation by a previously undocumented mechanism. Collectively, these observations provide insight into the me-chanism of phosphorylation-dependent activation unique to Spo0A.

Heterologous expression and enzymatic characterization of γ-glutamyltranspeptidase from Bacillus amyloliquefaciens: Jung-Min Lee , Jaejung Lee , Gyeong-Hwa Nam , Byung-Sam Son , Myoung-Uoon Jang , So-Won Lee , Byung-Serk Hurh , Tae-Jip Kim; J. Microbiol. 2017;55(2):147-152. Published online January 26, 2017; DOI: https://doi.org/10.1007/s12275-017-6638-6

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16 Citations

Abstract: γ-Glutamyltranspeptidase (GGT) catalyzes the cleavage of γ- glutamyl compounds and the transfer of γ-glutamyl moiety to water or to amino acid/peptide acceptors. GGT can be utilized for the generation of γ-glutamyl peptides or glutamic acid, which are used as food taste enhancers. In the present study, Bacillus amyloliquefaciens SMB469 with high GGT activity was isolated from Doenjang, a traditional fermented soy food of Korea. The gene encoding GGT from B. amyloliquefaciens SMB469 (BaGGT469) was cloned from the isolate, and heterologously expressed in E. coli and B. subtilis. For comparison, three additional GGT genes were cloned from B. subtilis 168, B. licheniformis DSM 13, and B. amyloliquefaciens FZB42. The BaGGT469 protein was composed of 591 amino acids. The final protein comprises two separate polypeptide chains of 45.7 and 19.7 kDa, generated via autocatalytic cleavage. The specific activity of BaGGT469 was determined to be 17.8 U/mg with γ-L-glutamyl-p-nitroanilide as the substrate and diglycine as the acceptor. GGTs from B. amyloliquefaciens showed 1.4- and 1.7-fold higher transpeptidase activities than those from B. subtilis and B. licheniformis, respectively. Especially, recombinant B. subtilis expressing BaGGT469 demonstrated 11- and 23-fold higher GGT activity than recombinant E. coli and the native B. amyloliquefaciens, respectively, did. These results suggest that BaGGT469 can be utilized for the enzymatic production of various γ- glutamyl compounds.

Alteration in the ultrastructural morphology of mycelial hyphae and the dynamics of transcriptional activity of lytic enzyme genes during basidiomycete morphogenesis: Elena Vetchinkina , Maria Kupryashina , Vladimir Gorshkov , Marina Ageeva , Yuri Gogolev , Valentina Nikitina; J. Microbiol. 2017;55(4):280-288. Published online January 26, 2017; DOI: https://doi.org/10.1007/s12275-017-6320-z

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Abstract: The morphogenesis of macromycetes is a complex multilevel process resulting in a set of molecular-genetic, physiological- biochemical, and morphological-ultrastructural changes in the cells. When the xylotrophic basidiomycetes Lentinus edodes, Grifola frondosa, and Ganoderma lucidum were grown on wood waste as the substrate, the ultrastructural morphology of the mycelial hyphal cell walls differed considerably between mycelium and morphostructures. As the macromycetes passed from vegetative to generative development, the expression of the tyr1, tyr2, chi1, chi2, exg1, exg2, and exg3 genes was acti-vated. These genes encode enzymes such as tyrosinase, chi-tinase, and glucanase, which play essential roles in cell wall growth and morphogenesis.

Review

MINIREVIEW] High-resolution imaging of the microbial cell surface: Ki Woo Kim; J. Microbiol. 2016;54(11):703-708. Published online October 29, 2016; DOI: https://doi.org/10.1007/s12275-016-6348-5

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Abstract: Microorganisms, or microbes, can function as threatening pathogens that cause disease in humans, animals, and plants; however, they also act as litter decomposers in natural ecosystems. As the outermost barrier and interface with the environment, the microbial cell surface is crucial for cell-to-cell communication and is a potential target of chemotherapeutic agents. Surface ultrastructures of microbial cells have typically been observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Owing to its characteristics of low-temperature specimen preparation and superb resolution (down to 1 nm), cryo-field emission SEM has revealed paired rodlets, referred to as hydrophobins, on the cell walls of bacteria and fungi. Recent technological advances in AFM have enabled high-speed live cell imaging in liquid at the nanoscale level, leading to clear visualization of celldrug interactions. Platinum-carbon replicas from freeze-fractured fungal spores have been observed using transmission electron microscopy, revealing hydrophobins with varying dimensions. In addition, AFM has been used to resolve bacteriophages in their free state and during infection of bacterial cells. Various microscopy techniques with enhanced spatial resolution, imaging speed, and versatile specimen preparation are being used to document cellular structures and events, thus addressing unanswered biological questions.

Journal Article

Identification of D-amino acid dehydrogenase as an upstream regulator of the autoinduction of a putative acyltransferase in Corynebacterium glutamicum: Jung-Hoon Lee , Yong-Jae Kim , Hee-Sung Shin , Heung-Shick Lee , Shouguang Jin , Un-Hwan Ha; J. Microbiol. 2016;54(6):432-439. Published online May 27, 2016; DOI: https://doi.org/10.1007/s12275-016-6046-3

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Abstract: Expression of a putative acyltransferase encoded by NCgl- 0350 of Corynebacterium glutamicum is induced by cell-free culture fluids obtained from stationary-phase growth of both C. glutamicum and Pseudomonas aeruginosa, providing evidence for interspecies communication. Here, we further confirmed that such communication occurs by showing that acyltransferase expression is induced by culture fluid obtained from diverse Gram-negative and -positive bacterial strains, including Escherichia coli, Salmonella Typhimurium, Bacillus subtilis, Staphylococcus aureus, Mycobacterium sp. strain JC1, and Mycobacterium smegmatis. A homologous acyltransferase encoded by PA5238 of P. aeruginosa was also induced by fluids obtained from P. aeruginosa as well as other bacterial strains, as observed for NCgl0350 of C. glutamicum. Because C. glutamicum is difficult to study using molecular approaches, the homologous gene PA5238 of P. aeruginosa was used to identify PA5309 as an upstream regulator of expression. A homologous D-amino acid dehydrogenase encoded by NCgl- 2909 of C. glutamicum was cloned based on amino acid similarity to PA5309, and its role in the regulation of NCgl0350 expression was confirmed. Moreover, NCgl2909 played positive roles in growth of C. glutamicum. Thus, we identified a D-amino acid dehydrogenase as an upstream regulator of the autoinduction of a putative acyltransferase in C. glutamicum.

Research Support, Non-U.S. Gov'ts

Role of bacterial γ-glutamyltranspeptidase as a novel virulence factor in bone-resorbing pathogenesis: Jinmoon Kim , Sungil Jang , Aeryun Kim , Hanfu Su , Niluka Gunawardhana , Yeong-Eui Jeon , Eun Jung Bak , Ji-Hye Kim , Jeong-Heon Cha; J. Microbiol. 2016;54(5):396-402. Published online April 20, 2016; DOI: https://doi.org/10.1007/s12275-016-6137-1

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Abstract: Mammalian γ-glutamyltranspeptidase (GGT) has been identified as a bone-resorbing factor. Since GGT of Bacillus subtilis exhibits similarity in their primary structure and enzymatic characteristics with mammalian GGTs, the bone-resorbing activity of bacterial GGT was examined in this study. Osteoclastogenesis was performed in a co-culture system of mouse calvaria-derived osteoblasts and bone marrow cells. A conditioned medium from GGT-overproducing B. subtilis culture showed significantly higher activity of osteoclast formation than a conditioned medium from wild-type B. subtilis culture. Recombinant GGT (rGGT) of wild-type B. subtilis and an enzymatic activity-defected rGGT of B. subtilis 2288 mutant were expressed in Escherichia coli and purified using His tag. Both purified rGGTs induced similar levels of osteoclastogenesis, suggesting that B. subtilis GGT possesses virulent boneresorbing activity and its activity is probably independent of its enzymatic activity. Furthermore, a recombinant protein of B. subtilis GGT heavy subunit (Bs rGGT/H) showed strong activity of osteoclastogenesis while the light subunit failed to show strong activity, suggesting that the bone-resorbing activity is mainly located at the heavy subunit. More importantly, the GGT enzymatic activity may not be required for this virulence activity since the light subunit contains the catalytic pocket. In addition, B. subtilis rGGT stimulated mRNA expressions of receptor activator of nuclear factor kappa-B ligand (RANKL) and cyclooxygenase-2 (COX-2), while an osteoprotegerin inhibited the osteoclast formation induced by Bs rGGT/H. This is the first demonstration that bacterial GGT itself is sufficient to act as a bone-resorbing virulence factor via RANKL-dependent pathway. Therefore, it can be hypothesized that GGT of periodontopathic bacteria may play an important role as a virulence factor in bone destruction.

Bacillus cheonanensis sp. nov. Isolated from Near Poultry Farm Soil: Hyun-Ju Kim , Cheol-Su Park , Siwon Lee , Tae-Young Ahn; J. Microbiol. 2014;52(7):554-558. Published online May 30, 2014; DOI: https://doi.org/10.1007/s12275-014-3458-9

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Abstract: A novel bacterial strain, designated PFS-5T, was isolated from the soil environment with feces of a live poultry farm located in Cheonan, Republic of Korea. Strain PFS-5T was Gram-staining-positive, motile, strictly aerobic bacterium, rod-shaped, and endospore-forming. The strain contained meso-diaminopimelic acid in their peptidoglycan and MK-7 menaquinone. The major fatty acids were anteiso-C15:0 (44.2%), C16:0 (22.2%), and iso-C15:0 (16.7%). The DNA G+C content was 40.1 mol%. Comparative 16S rRNA gene sequence analysis identified strain PFS-5T in the genus Bacillus, exhibiting the highest level of sequence similarity with type strain of B. herbersteinensis D-1,5aT (96.9%), B. humi LMG 22167T (96.7%), B. alkalitelluris BA288T (96.1%), B. litoralis SW-211T (96.0%), and B. luteolus YIM93174T (95.5%). The major polar lipids of PFS-5T were diphosphatidylglycerol and phosphatidylglycerol. On the basis of result from poly-phasic data, strain PFS-5T represents a novel species, for which the name Bacillus cheonanensis sp. nov. is proposed (Type strain PFS-5T= KACC 17469T= JCM19333T).

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