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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.
Repeated Exposure of Vancomycin to Vancomycin-Susceptible Staphylococcus aureus (VSSA) Parent Emerged VISA and VRSA Strains with Enhanced Virulence Potentials.
An Nguyen, J Jean Sophy Roy, Ji-Hoon Kim, Kyung-Hee Yun, Wonsik Lee, Kyeong Kyu Kim, Truc Kim, Akhilesh Kumar Chaurasia
J. Microbiol. 2024;62(7):535-553.   Published online May 30, 2024
DOI: https://doi.org/10.1007/s12275-024-00139-8
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AbstractAbstract
The emergence of resistance against the last-resort antibiotic vancomycin in staphylococcal infections is a serious concern for human health. Although various drug-resistant pathogens of diverse genetic backgrounds show higher virulence potential, the underlying mechanism behind this is not yet clear due to variability in their genetic dispositions. In this study, we investigated the correlation between resistance and virulence in adaptively evolved isogenic strains. The vancomycin-susceptible Staphylococcus aureus USA300 was exposed to various concentrations of vancomycin repeatedly as a mimic of the clinical regimen to obtain mutation(s)-accrued-clonally-selected (MACS) strains. The phenotypic analyses followed by expression of the representative genes responsible for virulence and resistance of MACS strains were investigated. MACS strains obtained under 2 and 8 µg/ml vancomycin, named Van2 and Van8, respectively; showed enhanced vancomycin minimal inhibitory concentrations (MIC) to 4 and 16 µg/ml, respectively. The cell adhesion and invasion of MACS strains increased in proportion to their MICs. The correlation between resistance and virulence potential was partially explained by the differential expression of genes known to be involved in both virulence and resistance in MACS strains compared to parent S. aureus USA300. Repeated treatment of vancomycin against vancomycin-susceptible S. aureus (VSSA) leads to the emergence of vancomycin-resistant strains with variable levels of enhanced virulence potentials.
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.
Transcriptomic Insights into Archaeal Nitrification in the Amundsen Sea Polynya, Antarctica
Joo-Han Gwak , Samuel Imisi Awala , So-Jeong Kim , Sang-Hoon Lee , Eun-Jin Yang , Jisoo Park , Jinyoung Jung , Sung-Keun Rhee
J. Microbiol. 2023;61(11):967-980.   Published online December 7, 2023
DOI: https://doi.org/10.1007/s12275-023-00090-0
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AbstractAbstract
Antarctic polynyas have the highest Southern Ocean summer primary productivity, and due to anthropogenic climate change, these areas have formed faster recently. Ammonia-oxidizing archaea (AOA) are among the most ubiquitous and abundant microorganisms in the ocean and play a primary role in the global nitrogen cycle. We utilized metagenomics and metatranscriptomics to gain insights into the physiology and metabolism of AOA in polar oceans, which are associated with ecosystem functioning. A polar-specific ecotype of AOA, from the “Candidatus Nitrosomarinus”-like group, was observed to be dominant in the Amundsen Sea Polynya (ASP), West Antarctica, during a succession of summer phytoplankton blooms. AOA had the highest transcriptional activity among prokaryotes during the bloom decline phase (DC). Metatranscriptomic analysis of key genes involved in ammonia oxidation, carbon fixation, transport, and cell division indicated that this polar AOA ecotype was actively involved in nitrification in the bloom DC in the ASP. This study revealed the physiological and metabolic traits of this key polar-type AOA in response to phytoplankton blooms in the ASP and provided insights into AOA functions in polar oceans.
Development of a Novel Korean H9‑Specific rRT‑PCR Assay and Its Application for Avian Influenza Virus Surveillance in Korea
Mingeun Sagong , Yong-Myung Kang , Na Yeong Kim , Eun Bi Noh , Gyeong-Beom Heo , Se-Hee An , Youn-Jeong Lee , Young Ki Choi , Kwang-Nyeong Lee
J. Microbiol. 2023;61(10):929-936.   Published online November 27, 2023
DOI: https://doi.org/10.1007/s12275-023-00088-8
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AbstractAbstract
Since the 2000s, the Y439 lineage of H9N2 avian influenza virus (AIV) has been the predominant strain circulating in poultry in Korea; however, in 2020, the Y280 lineage emerged and spread rapidly nationwide, causing large economic losses. To prevent further spread and circulation of such viruses, rapid detection and diagnosis through active surveillance programs are crucial. Here, we developed a novel H9 rRT-PCR assay that can detect a broad range of H9Nx viruses in situations in which multiple lineages of H9 AIVs are co-circulating. We then evaluated its efficacy using a large number of clinical samples. The assay, named the Uni Kor-H9 assay, showed high sensitivity for Y280 lineage viruses, as well as for the Y439 lineage originating in Korean poultry and wild birds. In addition, the assay showed no cross-reactivity with other subtypes of AIV or other avian pathogens. Furthermore, the Uni Kor-H9 assay was more sensitive, and had higher detection rates, than reference H9 rRT-PCR methods when tested against a panel of domestically isolated H9 AIVs. In conclusion, the novel Uni Kor-H9 assay enables more rapid and efficient diagnosis than the “traditional” method of virus isolation followed by subtyping RT-PCR. Application of the new H9 rRT-PCR assay to AI active surveillance programs will help to control and manage Korean H9 AIVs more efficiently.
Comparison of Conjunctival Sac Microbiome between Low and High Myopic Eyes
Kang Xiao , Zhengyu Chen , Qin Long
J. Microbiol. 2023;61(5):571-578.   Published online April 21, 2023
DOI: https://doi.org/10.1007/s12275-023-00045-5
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AbstractAbstract
Microbial communities played a vital role in maintaining homeostasis of ocular surface. However, no studies explored the myopia-associated conjunctiva microbiota changes until now. In this study, conjunctival sac swab specimens were collected from 12 eyes of low myopia (LM), and 14 eyes of high myopia (HM) patients. The V3–V4 region of the 16S rRNA gene was amplified and then sequenced. Statistical analysis was performed to investigate differences in the taxonomy and diversity between two groups. Compared to LM, higher Ocular Surface Disease Index (OSDI) scores were observed in HM group. The Shannon index of the HM was lower than that of the LM group (P = 0.017). Principle coordinate analysis and Partial Least Squares Discrimination Analysis showed distinct microbiome composition between two groups. At the phylum level, there were higher relative abundances of Proteobacteria (68.27% vs 38.51%) and lower abundances of Actinobacteria (3.71% vs 9.19%) in HM, compared to LM group (P = 0.031, 0.010, respectively). At the genus level, the abundances of Acinetobacter in HM (18.16%) were significantly higher than the LM (6.52%) group (P = 0.011). Actinobacteria levels were negatively correlated with the myopic spherical equivalent and OSDI scores. Moreover, positive correlations were found between Proteobacteria levels and OSDI scores, Acinetobacter levels were positively correlated with myopic spherical equivalent and OSDI scores. In conclusion, HM Patients have bacterial microbiota imbalance in the conjunctival sac, compared with LM patients. Proteobacteria, Actinobacteria, Acinetobacter may play roles in the HM associated ocular surface irritation.
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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AbstractAbstract
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.
Rhizosphere Microbial Community and Metabolites of Susceptible and Resistant Tobacco Cultivars to Bacterial Wilt
Wan Zhao , Yanyan Li , Chunlei Yang , Yong Yang , Yun Hu
J. Microbiol. 2023;61(4):389-402.   Published online March 7, 2023
DOI: https://doi.org/10.1007/s12275-023-00012-0
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AbstractAbstract
Soil-borne diseases are closely related to rhizosphere microecosystem. While, plant species and genotypes are important factors affected rhizosphere microecosystem. In this study, the rhizosphere soil microbial community and metabolites of susceptible and resistant tobacco cultivars were investigated. The results showed that there were significant differences in the rhizosphere microbial community and metabolites between susceptible cultivar Yunyan87 and resistant cultivar Fandi3. Furthermore, the rhizosphere soil of Fandi3 showed a higher microbial diversity than that of Yunyan87. The abundance of R. solanacearum was much higher in the rhizosphere soil of Yunyan87 than in the rhizosphere soil of Fandi3, resulting in a higher disease incidence and index. While the abundance of beneficial bacteria in the rhizosphere soil of Fandi3 were higher than that of Yunyan87. Additionally, there were significant differences in metabolites between Yunyan87 and Fandi3 cultivars, and 4-hydroxybenzaldehyde, 3-hydroxy-4-methoxybenzoic acid, vamillic aldehyde, benzoic acid, 4-hydroxybenzyl alcohol, p-hydroxybenzoic acid and phthalic acid were notably high in Yunyan87. Redundancy analysis (RDA) indicated that the rhizosphere microbial community of Fandi3 and Yunyan87 were highly correlated with various environmental factors and metabolites. Overall, susceptible and resistant tobacco cultivars had different impact on rhizosphere microbial community and metabolites. The results expand our understanding of the roles of tobacco cultivars in plant-micro-ecosystem interactions, and provide a basis for the control of tobacco bacterial wilt.
The Revision of Lichen Flora Around Maxwell Bay, King George Island, Maritime Antarctic
Jae Eun So , Josef P. Halda , Soon Gyu Hong , Jae&# , Ji Hee Kim
J. Microbiol. 2023;61(2):159-173.   Published online February 27, 2023
DOI: https://doi.org/10.1007/s12275-023-00015-x
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AbstractAbstract
Since the floristic study of lichens at the Barton and Weaver Peninsulas of King George Island in 2006, there have been intense investigations of the lichen flora of the two peninsulas as well as that of Fildes Peninsula and Ardley Island in Maxwell Bay, King George Island, South Shetland Islands, maritime Antarctic. In this study, a total of 104 species belonging to 53 genera, are identified from investigations of lichens that were collected in austral summer seasons from 2008 to 2016. Phenotypic and molecular analyses were incorporated for taxonomic identification. In particular, 31 species are found to be endemic to the Antarctic and 22 species are newly recorded to the Maxwell Bay region. Lepra dactylina, Stereocaulon caespitosum, and Wahlenbergiella striatula are newly recorded in the Antarctic, and the previously reported taxon Cladonia furcata is excluded from the formerly recorded list due to misidentification. We also provide ecological and geographical information about lichen associations and habitat preferences.
Genome Sequencing Highlights the Plant Cell Wall Degrading Capacity of Edible Mushroom Stropharia rugosoannulata
Mengpei Guo , Xiaolong Ma , Yan Zhou , Yinbing Bian , Gaolei Liu , Yingli Cai , Tianji Huang , Hongxia Dong , Dingjun Cai , Xueji Wan , Zhihong Wang , Yang Xiao , Heng Kang
J. Microbiol. 2023;61(1):83-93.   Published online February 1, 2023
DOI: https://doi.org/10.1007/s12275-022-00003-7
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AbstractAbstract
The basidiomycetous edible mushroom Stropharia rugosoannulata has excellent nutrition, medicine, bioremediation, and biocontrol properties. S. rugosoannulata has been widely and easily cultivated using agricultural by-products showing strong lignocellulose degradation capacity. However, the unavailable high-quality genome information has hindered the research on gene function and molecular breeding of S. rugosoannulata. This study provided a high-quality genome assembly and annotation from S. rugosoannulata monokaryotic strain QGU27 based on combined Illumina-Nanopore data. The genome size was about 47.97 Mb and consisted of 20 scaffolds, with an N50 of 3.73 Mb and a GC content of 47.9%. The repetitive sequences accounted for 17.41% of the genome, mostly long terminal repeats (LTRs). A total of 15,726 coding gene sequences were putatively identified with the BUSCO score of 98.7%. There are 142 genes encoding plant cell wall degrading enzymes (PCWDEs) in the genome, and 52, 39, 30, 11, 8, and 2 genes related to lignin, cellulose, hemicellulose, pectin, chitin, and cutin degradation, respectively. Comparative genomic analysis revealed that S. rugosoannulata is superior in utilizing aldehyde-containing lignins and is possible to utilize algae during the cultivation.
Potential Use of Mycobacterium paragordonae for Antimycobacterial Drug Screening Systems
Ga-Yeong Cha , Hyejun Seo , Jaehun Oh , Byoung-Jun Kim , Bum-Joon Kim
J. Microbiol. 2023;61(1):121-129.   Published online January 31, 2023
DOI: https://doi.org/10.1007/s12275-022-00009-1
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AbstractAbstract
Our recent genome-based study indicated that Mycobacterium paragordonae (Mpg) has evolved to become more adapted to an intracellular lifestyle within free-living environmental amoeba and its enhanced intracellular survival within Acanthamoeba castellanii was also proved. Here, we sought to investigate potential use of Mpg for antimycobacterial drug screening systems. Our data showed that Mpg is more susceptible to various antibiotics compared to the close species M. marinum (Mmar) and M. gordonae, further supporting its intracellular lifestyle in environments, which would explain its protection from environmental insults. In addition, we developed two bacterial whole-cell-based drug screening systems using a recombinant Mpg stain harboring a luciferase reporter vector (rMpg-LuxG13): one for direct application to rMpg-LuxG13 and the other for drug screening via the interaction of rMpg-LuxG13 with A. castellanii. Direct application to rMpg-LuxG13 showed lower inhibitory concentration 50 ( IC50) values of rifampin, isoniazid, clarithromycin, and ciprofloxacin against Mpg compared to Mmar. Application of drug screening system via the interaction of rMpg-LuxG13 with A. castellanii also exhibited lower IC50 values for rifampin against Mpg compared to Mmar. In conclusion, our data indicate that Mpg is more susceptible to various antibiotics than other strains. In addition, our data also demonstrate the feasibility of two whole cellbased drug screening systems using rMpg-LuxG13 strain for the discovery of novel anti-mycobacterial drugs.
Coumarin-based combined computational study to design novel drugs against Candida albicans
Akhilesh Kumar Maurya , Nidhi Mishra
J. Microbiol. 2022;60(12):1201-1207.   Published online November 10, 2022
DOI: https://doi.org/10.1007/s12275-022-2279-5
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AbstractAbstract
Candida species cause the most prevalent fungal illness, candidiasis. Candida albicans is known to cause bloodstream infections. This species is a commensal bacterium, but it can cause hospital–acquired diseases, particularly in COVID-19 patients with impaired immune systems. Candida infections have increased in patients with acute respiratory distress syndrome. Coumarins are both naturally occurring and synthetically produced. In this study, the biological activity of 40 coumarin derivatives was used to create a three-dimensional quantitative structure activity relationship (3D-QSAR) model. The training and test minimum inhibitory concentration values of C. albicans active compounds were split, and a regression model based on statistical data was established. This model served as a foundation for the creation of coumarin derivative QSARs. This is a unique way to create new therapeutic compounds for various ailments. We constructed novel structural coumarin derivatives using the derived QSAR model, and the models were confirmed using molecular docking and molecular dynamics simulation.
Genomic and physiological analysis of C50 carotenoid-producing novel Halorubrum ruber sp. nov.
Chi Young Hwang , Eui-Sang Cho , Won Jong Rhee , Eunjung Kim , Myung-Ji Seo
J. Microbiol. 2022;60(10):1007-1020.   Published online August 26, 2022
DOI: https://doi.org/10.1007/s12275-022-2173-1
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AbstractAbstract
A novel haloarchaeal species designated as MBLA0099T was isolated from seawater near Yeongheung Island. Cells were Gram-negative, non-motile, red-pigmented, and rod-shaped. They grew at 10–45°C, within pH 5.5–9.0, and between 7.5% and 30% NaCl concentrations. Cells were able to grow without Mg2+ and were lysed in distilled water. The size of the whole-genome and G + C content of DNA was 3.02 Mb and 68.9 mol%, respectively. Phylogenetic analysis shows that the strain MBLA0099T belongs to the genus Halorubrum. The average nucleotide and amino acid identity, and in silico DNA-DNA hybridization values were below the species delineation threshold. Pan-genomic analysis revealed that 3.2% of all genes present in strain MBLA0099T were unique to the strain. The red carotenoid produced by strain MBLA0099T was subjected to spectrometric and chromatographic analyses and confirmed to be bacterioruberin as C50 carotenoid. Mevalonic acid, terpenoid backbone, and carotenoid biosynthesis pathway were annotated for strain MBLA0099T. The C50 carotenoid production by strain MBLA0099T was also enhanced under various stress conditions including relatively netural pH, high oxidative and salinity conditions. Additionally, the strain MBLA0099T-derived bacterioruberin showed the antioxidant activity with EC50 value of 12.29 μg/ml, based on the evaluation of DPPH free radical scavenging activity. The present study would be the first report on the identification of C50 carotenoid from the strain MBLA0099T representing a novel species of the genus Halorubrum, for which the name Halorubrum ruber sp. nov. is proposed. The typestrain used was MBLA0099T (= KCTC 4296T = JCM 34701T).
Review
The crosstalk between bacteria and host autophagy: host defense or bacteria offense
Lin Zheng , Fang Wei , Guolin Li
J. Microbiol. 2022;60(5):451-460.   Published online April 29, 2022
DOI: https://doi.org/10.1007/s12275-022-2009-z
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AbstractAbstract
Xenophagy is a specific selective autophagy for the elimination of intracellular bacteria. Current evidence suggests that the processes for host autophagy system to recognize and eliminate invading bacteria are complex, and vary according to different pathogens. Although both ubiquitin-dependent and ubiquitin-independent autophagy exist in host to defense invading bacteria, successful pathogens have evolved diverse strategies to escape from or paralyze host autophagy system. In this review, we discuss the mechanisms of host autophagy system to recognize and eliminate intracellular pathogens and the mechanisms of different pathogens to escape from or paralyze host autophagy system, with a particular focus on the most extensively studied bacteria.
Journal Article
Lysobacter ciconiae sp. nov., and Lysobacter avium sp. nov., isolated from the faeces of an Oriental stork
So-Yeon Lee , Pil Soo Kim , Hojun Sung , Dong-Wook Hyun , Jin-Woo Bae
J. Microbiol. 2022;60(5):469-477.   Published online March 31, 2022
DOI: https://doi.org/10.1007/s12275-022-1647-5
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AbstractAbstract
Two Gram-stain-negative, mesophilic, strictly aerobic, nonspore forming, and yellow-pigmented strains with rod-shaped cells, designated H21R20T and H23M41T, were isolated from the faeces of an Oriental stork (Ciconia boyciana). Based on 16S rRNA gene sequences, both strains showed the highest similarity (98.3−98.4%) to the type strain of Lysobacter concretionis. Phylogenetic analysis based on the 16S rRNA genes and 92 bacterial core genes showed that strains H21R20T and H23M41T were robustly clustered with L. concretionis Ko07T. Whole genome sequencing revealed that the genomes of both strains were approximately 2.9 Mb in size. The DNA G + C contents of the H21R20T and H23M41T strains were 67.3 and 66.6%, respectively. The two strains showed 80.1−81.7% average nucleotide identity with L. concretionis Ko07T. Strain H21R20T grew optimally at 30°C and pH 8.0 and in the presence of 0.5–3% (wt/vol) NaCl, while strain H23M41T grew optimally at 30°C and pH 7.0–8.0 and in the presence of 0–3% (wt/vol) NaCl. Both strains possessed iso-C15:0, iso-C16:0 and summed feature 9 (iso-C17:1 ω9c and/or C16:0 10-methyl) as the major cellular fatty acids, ubiquinone Q-8 as a predominant quinone, and diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine as the major polar lipids. A multifaceted investigation demonstrated that strains H21R20T and H23M41T represent novel species of the genus Lysobacter, for which we propose the names Lysobacter ciconiae sp. nov. and Lysobacter avium sp. nov. for strains H21R20T (= KCTC 82316T = JCM 34832T) and H23M41T (= KCTC 62676T = JCM 33223T), respectively.

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