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Journal Articles
- Characterization and Comparative Genomic Analysis of vB_BceM_CEP1: A Novel Temperate Bacteriophage Infecting Burkholderia cepacia Complex.
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Momen Askoura, Eslam K Fahmy, Safya E Esmaeel, Wael A H Hegazy, Aliaa Abdelghafar
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J. Microbiol. 2024;62(11):1035-1055. Published online November 18, 2024
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DOI: https://doi.org/10.1007/s12275-024-00185-2
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Abstract
- The increasing prevalence of multidrug-resistant bacteria imminently threatens public health and jeopardizes nearly all aspects of modern medicine. The Burkholderia cepacia complex (Bcc) comprises Burkholderia cepacia and the related species of Gram-negative bacteria. Members of the Bcc group are opportunistic pathogens responsible for various chronic illnesses, including cystic fibrosis and chronic granulomatous disease. Phage therapy is emerging as a potential solution to combat the antimicrobial resistance crisis. In this study, a temperate phage vB_BceM_CEP1 was isolated from sewage and fully characterized.
Transmission electron microscopy indicated that vB_BceM_CEP1 belongs to the family Peduoviridae. The isolated phage demonstrated enhanced environmental stability and antibiofilm potential. One-step growth analysis revealed a latent period of 30 min and an average burst size of 139 plaque-forming units per cell.
The genome of vB_BceM_CEP1 consists of 32,486 bp with a GC content of 62.05%. A total of 40 open reading frames were annotated in the phage genome, and none of the predicted genes was annotated as tRNA. Notably, genes associated with antibiotic resistance, host virulence factors, and toxins were absent from the vB_BceM_CEP1 genome. Based on its unique phenotype and phylogeny, the isolated phage vB_BceM_CEP1 is classified as a new temperate phage with lytic activity.
The findings of this study enhance our understanding of the diversity of Bcc phages.
- Genomic Characterization and Comparative Analysis of Streptococcus zhangguiae sp. nov. Isolated from the Respiratory Tract of Marmota Himalayana.
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Caixin Yang, Jiajia Ma, Huimin Zhou, Jing Yang, Ji Pu, Shan Lu, Dong Jin, Liyun Liu, Kui Dong, Jianguo Xu
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J. Microbiol. 2024;62(11):951-963. Published online November 4, 2024
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DOI: https://doi.org/10.1007/s12275-024-00177-2
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Abstract
- Two Gram-stain-positive, oxidase-negative, non-motile, facultative anaerobic, α-hemolytic, coccus-shaped bacteria (zg-86T and zg-70) were isolated from the respiratory tracts of marmots (Marmota Himalayana) on the Qinghai-Tibet Plateau of China. Phylogenetic analysis of the 16S rRNA gene and 545 core genes revealed that these two strains belong to the Streptococcus genus. These strains were most closely related to Streptococcus respiraculi HTS25T, Streptococcus cuniculi CCUG 65085T, and Streptococcus marmotae HTS5T. The average nucleotide identity (ANI) and digital DNA‒DNA hybridization (dDDH) were below the threshold for species delineation. The predominant cellular fatty acids (CFAs) in this novel species were C16:0, C18:0, and C18:1ω9c, whereas the primary polar lipids were phosphatidylglycerol (PG), phosphatidylethanolamine (PE) and an unknown phosphoglycolipid (PGL). The optimal growth conditions for the strains were 37 °C, pH 7.0, and 0.5% (w/v) NaCl on brain-heart infusion (BHI) agar supplemented with 5% defibrinated sheep blood. Comparative genomics analyses revealed the potential pathogenicity of strain zg-86T through comparisons with suis subclade strains in terms of virulence factors, pathogen-host interactions (PHIs) and mobile genetic factors (MGEs). Based on the phenotypic characteristics and phylogenetic analyses, we propose that these two isolates represent novel species in the genus Streptococcus, for which the names Streptococcus zhangguiae sp. nov. (the type strain zg-86T=GDMCC 1.1758T=JCM 34273T) is proposed.
Reviews
- Extensive Genomic Rearrangement of Catalase-Less Cyanobloom-Forming Microcystis aeruginosa in Freshwater Ecosystems.
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Minkyung Kim, Jaejoon Jung, Wonjae Kim, Yerim Park, Che Ok Jeon, Woojun Park
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J. Microbiol. 2024;62(11):933-950. Published online October 8, 2024
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DOI: https://doi.org/10.1007/s12275-024-00172-7
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Abstract
- Many of the world's freshwater ecosystems suffer from cyanobacteria-mediated blooms and their toxins. However, a mechanistic understanding of why and how Microcystis aeruginosa dominates over other freshwater cyanobacteria during warmer summers is lacking. This paper utilizes comparative genomics with other cyanobacteria and literature reviews to predict the gene functions and genomic architectures of M. aeruginosa based on complete genomes. The primary aim is to understand this species' survival and competitive strategies in warmer freshwater environments. M. aeruginosa strains exhibiting a high proportion of insertion sequences (~ 11%) possess genomic structures with low synteny across different strains. This indicates the occurrence of extensive genomic rearrangements and the presence of many possible diverse genotypes that result in greater population heterogeneities than those in other cyanobacteria in order to increase survivability during rapidly changing and threatening environmental challenges.
Catalase-less M. aeruginosa strains are even vulnerable to low light intensity in freshwater environments with strong ultraviolet radiation. However, they can continuously grow with the help of various defense genes (e.g., egtBD, cruA, and mysABCD) and associated bacteria. The strong defense strategies against biological threats (e.g., antagonistic bacteria, protozoa, and cyanophages) are attributed to dense exopolysaccharide (EPS)-mediated aggregate formation with efficient buoyancy and the secondary metabolites of M. aeruginosa cells. Our review with extensive genome analysis suggests that the ecological vulnerability of M. aeruginosa cells can be overcome by diverse genotypes, secondary defense metabolites, reinforced EPS, and associated bacteria.
- Microbiome-Mucosal Immunity Nexus: Driving Forces in Respiratory Disease Progression.
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Young Chae Park, Soo Yeon Choi, Yunah Cha, Hyeong Won Yoon, Young Min Son
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J. Microbiol. 2024;62(9):709-725. Published online September 6, 2024
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DOI: https://doi.org/10.1007/s12275-024-00167-4
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Abstract
- The importance of the complex interplay between the microbiome and mucosal immunity, particularly within the respiratory tract, has gained significant attention due to its potential implications for the severity and progression of lung diseases. Therefore, this review summarizes the specific interactions through which the respiratory tract-specific microbiome influences mucosal immunity and ultimately impacts respiratory health. Furthermore, we discuss how the microbiome affects mucosal immunity, considering tissue-specific variations, and its capacity in respiratory diseases containing asthma, chronic obstructive pulmonary disease, and lung cancer. Additionally, we investigate the external factors which affect the relationship between respiratory microbiome and mucosal immune responses. By exploring these intricate interactions, this review provides valuable insights into the potential for microbiome-based interventions to modulate mucosal immunity and alleviate the severity of respiratory diseases.
Journal Articles
- Cultivation of Diverse Novel Marine Bacteria from Deep Ocean Sediment Using Spent Culture Supernatant of Ca. Bathyarchaeia Enrichment.
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Sidra Erum Ishaq, Tariq Ahmad, Lewen Liang, Ruize Xie, Tiantian Yu, Yinzhao Wang, Fengping Wang
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J. Microbiol. 2024;62(8):611-625. Published online July 10, 2024
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DOI: https://doi.org/10.1007/s12275-024-00145-w
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Abstract
- Most microorganisms resist pure cultivation under conventional laboratory conditions. One of the primary issues for this un-culturability is the absence of biologically produced growth-promoting factors in traditionally defined growth media. However, whether cultivating microbes by providing spent culture supernatant of pivotal microbes in the growth medium can be an effective approach to overcome this limitation is still an under-explored area of research. Here, we used the spent culture medium (SCM) method to isolate previously uncultivated marine bacteria and compared the efficiency of this method with the traditional cultivation (TC) method. In the SCM method, Ca. Bathyarchaeia-enriched supernatant (10%) was used along with recalcitrant organic substrates such as lignin, humic acid, and organic carbon mixture. Ca. Bathyarchaeia, a ubiquitous class of archaea, have the capacity to produce metabolites, making their spent culture supernatant a key source to recover new bacterial stains. Both cultivation methods resulted in the recovery of bacterial species from the phyla Pseudomonadota, Bacteroidota, Actinomycetota, and Bacillota. However, our SCM approach also led to the recovery of species from rarely cultivated groups, such as Planctomycetota, Deinococcota, and Balneolota. In terms of the isolation of new taxa, the SCM method resulted in the cultivation of 80 potential new strains, including one at the family, 16 at the genus, and 63 at the species level, with a novelty ratio of ~ 35% (80/219). In contrast, the TC method allowed the isolation of ~ 10% (19/171) novel strains at species level only. These findings suggest that the SCM approach improved the cultivation of novel and diverse bacteria.
- Non-Mitochondrial Aconitase-2 Mediates the Transcription of Nuclear-Encoded Electron Transport Chain Genes in Fission Yeast.
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Ho-Jung Kim, Soo-Yeon Cho, Soo-Jin Jung, Yong-Jun Cho, Jung-Hye Roe, Kyoung-Dong Kim
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J. Microbiol. 2024;62(8):639-648. Published online June 25, 2024
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DOI: https://doi.org/10.1007/s12275-024-00147-8
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Abstract
- Aconitase-2 (Aco2) is present in the mitochondria, cytosol, and nucleus of fission yeast. To explore its function beyond the well-known role in the mitochondrial tricarboxylic acid (TCA) cycle, we conducted genome-wide profiling using the aco2ΔNLS mutant, which lacks a nuclear localization signal (NLS). The RNA sequencing (RNA-seq) data showed a general downregulation of electron transport chain (ETC) genes in the aco2ΔNLS mutant, except for those in the complex II, leading to a growth defect in respiratory-prone media.
Complementation analysis with non-catalytic Aco2 [aco2ΔNLS + aco2(3CS)], where three cysteines were substituted with serine, restored normal growth and typical ETC gene expression. This suggests that Aco2's catalytic activity is not essential for its role in ETC gene regulation. Our mRNA decay assay indicated that the decrease in ETC gene expression was due to transcriptional regulation rather than changes in mRNA stability. Additionally, we investigated the Php complex's role in ETC gene regulation and found that ETC genes, except those within complex II, were downregulated in php3Δ and php5Δ strains, similar to the aco2ΔNLS mutant. These findings highlight a novel role for nuclear aconitase in ETC gene regulation and suggest a potential connection between the Php complex and Aco2.
- RapB Regulates Cell Adhesion and Migration in Dictyostelium, Similar to RapA.
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Uri Han, Nara Han, Byeonggyu Park, Taeck Joong Jeon
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J. Microbiol. 2024;62(8):627-637. Published online June 17, 2024
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DOI: https://doi.org/10.1007/s12275-024-00143-y
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Abstract
- Ras small GTPases act as molecular switches in various cellular signaling pathways, including cell migration, proliferation, and differentiation. Three Rap proteins are present in Dictyostelium; RapA, RapB, and RapC. RapA and RapC have been reported to have opposing functions in the control of cell adhesion and migration. Here, we investigated the role of RapB, a member of the Ras GTPase subfamily in Dictyostelium, focusing on its involvement in cell adhesion, migration, and developmental processes. This study revealed that RapB, similar to RapA, played a crucial role in regulating cell morphology, adhesion, and migration. rapB null cells, which were generated by CRISPR/Cas9 gene editing, displayed altered cell size, reduced cell-substrate adhesion, and increased migration speed during chemotaxis. These phenotypes of rapB null cells were restored by the expression of RapB and RapA, but not RapC. Consistent with these results, RapB, similar to RapA, failed to rescue the phenotypes of rapC null cells, spread morphology, increased cell adhesion, and decreased migration speed during chemotaxis. Multicellular development of rapB null cells remained unaffected. These results suggest that RapB is involved in controlling cell morphology and cell adhesion. Importantly, RapB appears to play an inhibitory role in regulating the migration speed during chemotaxis, possibly by controlling cell-substrate adhesion, resembling the functions of RapA. These findings contribute to the understanding of the functional relationships among Ras subfamily proteins.
- Autotrophy to Heterotrophy: Shift in Bacterial Functions During the Melt Season in Antarctic Cryoconite Holes.
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Aritri Sanyal, Runa Antony, Gautami Samui, Meloth Thamban
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J. Microbiol. 2024;62(8):591-609. Published online May 30, 2024
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DOI: https://doi.org/10.1007/s12275-024-00140-1
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Abstract
- Microbes residing in cryoconite holes (debris, water, and nutrient-rich ecosystems) on the glacier surface actively participate in carbon and nutrient cycling. Not much is known about how these communities and their functions change during the summer melt-season when intense ablation and runoff alter the influx and outflux of nutrients and microbes. Here, we use high-throughput-amplicon sequencing, predictive metabolic tools and Phenotype MicroArray techniques to track changes in bacterial communities and functions in cryoconite holes in a coastal Antarctic site and the surrounding fjord, during the summer season. The bacterial diversity in cryoconite hole meltwater was predominantly composed of heterotrophs (Proteobacteria) throughout the season. The associated functional potentials were related to heterotrophic-assimilatory and -dissimilatory pathways. Autotrophic Cyanobacterial lineages dominated the debris community at the beginning and end of summer, while heterotrophic Bacteroidota- and Proteobacteria-related phyla increased during the peak melt period. Predictive functional analyses based on taxonomy show a shift from predominantly phototrophy-related functions to heterotrophic assimilatory pathways as the melt-season progressed. This shift from autotrophic to heterotrophic communities within cryoconite holes can affect carbon drawdown and nutrient liberation from the glacier surface during the summer. In addition, the flushing out and export of cryoconite hole communities to the fjord could influence the biogeochemical dynamics of the fjord ecosystem.
- Sporosarcina jeotgali sp. nov., Sporosarcina oncorhynchi sp. nov., and Sporosarcina trichiuri sp. nov., Isolated from Jeotgal, a Traditional Korean Fermented Seafood.
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Ah-In Yang, Bora Kim, Sung-Hong Joe, Hae-In Joe, Hanna Choe, Ki Hyun Kim, Min Ok Jun, Na-Ri Shin
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J. Microbiol. 2024;62(4):285-296. Published online April 8, 2024
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DOI: https://doi.org/10.1007/s12275-024-00106-3
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Abstract
- Three novel, Gram-stain-positive, obligate aerobic, catalase- and oxidase-positive bacterial strains, designated B2O-1(T), T2O-4(T), and 0.2-SM1T-5(T), were isolated from jeotgal, a traditional Korean fermented seafood. Strains B2O-1(T), T2O-4(T), and 0.2-SM1T-5(T) exhibited distinct colony colors, characterized by pink, yellow, and red opaque circular colonies, respectively. Phylogenetic analysis revealed that three strains formed a paraphyletic clade within the genus Sporosarcina and shared < 99.0% similarity with Sporosarcina aquimarina KCTC 3840(T) and Sporosarcina saromensis KCTC 13119(T) in their 16S rRNA gene sequences. The three strains exhibiting Orthologous Average Nucleotide Identity values < 79.3% and digital DNA-DNA hybridization values < 23.1% within the genus Sporosarcina affirmed their distinctiveness. Strains B2O-1(T), T2O-4(T), and 0.2-SM1T-5(T) contained MK-7 as a sole respiratory menaquinone and A4α type peptidoglycan based on lysine with alanine, glutamic acid, and aspartic acid. The common polar lipids include diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine.
Strain T2O-4(T) contained one unidentified phospholipid, whereas strain 0.2-SM1T-5(T) contained two unidentified phospholipids. Cellular fatty acid profiles, with C(15:0) anteiso as the major fatty acid, supported the affiliation of the three strains to the genus Sporosarcina. Based on the polyphasic characteristics, strains B2O-1(T) (= KCTC 43506(T) = JCM 36032(T)), T2O-4(T) (= KCTC 43489(T) = JCM 36031(T)), and 0.2-SM1T-5(T) (= KCTC 43519(T) = JCM 36034(T)) represent three novel species within the genus Sporosarcina, named Sporosarcina jeotgali sp. nov., Sporosarcina oncorhynchi sp. nov., and Sporosarcina trichiuri sp. nov., respectively.
- Saxibacter everestensis gen. nov., sp. nov., A Novel Member of the Family Brevibacteriaceae, Isolated from the North Slope of Mount Everest.
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Mao Tian, Shiyu Wu, Wei Zhang, Gaosen Zhang, Xue Yu, Yujie Wu, Puchao Jia, Binglin Zhang, Tuo Chen, Guangxiu Liu
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J. Microbiol. 2024;62(4):277-284. Published online March 6, 2024
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DOI: https://doi.org/10.1007/s12275-024-00108-1
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Abstract
- 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)).
- Mycobacterium tuberculosis PE_PGRS45 (Rv2615c) Promotes Recombinant Mycobacteria Intracellular Survival via Regulation of Innate Immunity, and Inhibition of Cell Apoptosis
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Tao Xu , Chutong Wang , Minying Li , Jing Wei , Zixuan He , Zhongqing Qian , Xiaojing Wang , Hongtao Wang
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J. Microbiol. 2024;62(1):49-62. Published online February 9, 2024
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DOI: https://doi.org/10.1007/s12275-023-00101-0
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Abstract
- Tuberculosis (TB), a bacterial infectious disease caused by Mycobacterium tuberculosis (M. tuberculosis), is a significant
global public health problem. Mycobacterium tuberculosis expresses a unique family of PE_PGRS proteins that have been
implicated in pathogenesis. Despite numerous studies, the functions of most PE_PGRS proteins in the pathogenesis of
mycobacterium infections remain unclear. PE_PGRS45 (Rv2615c) is only found in pathogenic mycobacteria. In this study,
we successfully constructed a recombinant Mycobacterium smegmatis (M. smegmatis) strain which heterologously expresses
the PE_PGRS45 protein. We found that overexpression of this cell wall-associated protein enhanced bacterial viability under
stress in vitro and cell survival in macrophages. MS_PE_PGRS45 decreased the secretion of pro-inflammatory cytokines such
as IL-1β, IL-6, IL-12p40, and TNF-α. We also found that MS_PE_PGRS45 increased the expression of the anti-inflammatory
cytokine IL-10 and altered macrophage-mediated immune responses. Furthermore, PE_PGRS45 enhanced the survival rate
of M. smegmatis in macrophages by inhibiting cell apoptosis. Collectively, our findings show that PE_PGRS45 is a virulent
factor actively involved in the interaction with the host macrophage.
- Genetic and Functional Characterization of a Salicylate 1‑monooxygenase Located on an Integrative and Conjugative Element (ICE) in Pseudomonas stutzeri AJR13
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Igor Ivanovski , Gerben J. Zylstra
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J. Microbiol. 2023;61(12):1025-1032. Published online December 15, 2023
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DOI: https://doi.org/10.1007/s12275-023-00093-x
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Abstract
- Pseudomonas stutzeri strain AJR13 was isolated for growth on the related compounds biphenyl (BPH) and diphenylmethane
(DPM). The BPH and DPM degradative pathway genes are present on an integrative and conjugative element (ICE) in the
chromosome. Examination of the genome sequence of AJR13 revealed a gene encoding a salicylate 1-monooxygenase (salA)
associated with the ICE even though AJR13 did not grow on salicylate. Transfer of the ICE to the well-studied Pseudomonas
putida KT2440 resulted in a KT2440 strain that could grow on salicylate. Knockout mutagenesis of the salA gene on the
ICE in KT2440 eliminated the ability to grow on salicylate. Complementation of the knockout with the cloned salA gene
restored growth on salicylate. Transfer of the cloned salA gene under control of the lac promoter to KT2440 resulted in a
strain that could grow on salicylate. Heterologous expression of the salA gene in E. coli BL21 DE3 resulted in the production
of catechol from salicylate, confirming that it is indeed a salicylate 1-monooxygenase. Interestingly, transfer of the cloned
salA gene under control of the lac promoter to AJR13 resulted in a strain that could now grow on salicylate, suggesting that
gene expression for the downstream catechol pathway is intact.
- Impact of Elevational Gradients and Chemical Parameters on Changes in Soil Bacterial Diversity Under Semiarid Mountain Region
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Salman Khan , Chun Han , Awais Iqbal , Chao Guan , Changming Zhao
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J. Microbiol. 2023;61(10):903-915. Published online November 23, 2023
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DOI: https://doi.org/10.1007/s12275-023-00085-x
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Abstract
- Elevation gradients, often regarded as “natural experiments or laboratories”, can be used to study changes in the distribution
of microbial diversity related to changes in environmental conditions that typically occur over small geographical scales. We
obtained bacterial sequences using MiSeq sequencing and clustered them into operational taxonomic units (OTUs). The total
number of reads obtained by the bacterial 16S rRNA sequencing analysis was 1,090,555, with an average of approximately
45,439 reads per sample collected from various elevations. The current study observed inconsistent bacterial diversity patterns
in samples from the lowest to highest elevations. 983 OTUs were found common among all the elevations. The most
unique OTUs were found in the soil sample from elevation_2, followed by elevation_1. Soil sample collected at elevation_6
had the least unique OTUs. Actinobacteria, Protobacteria, Chloroflexi were found most abundant bacterial phyla in current
study. Ammonium nitrogen (
NH4
+-N), and total phosphate (TP) are the main factors influencing bacterial diversity at elevations_
1. pH was the main factor influencing the bacterial diversity at elevations_2, elevation_3 and elevation_4. Our results
provide new visions on forming and maintaining soil microbial diversity along an elevational gradient and have implications
for microbial responses to environmental change in semiarid mountain ecosystems.
- Development of a Novel D‑Lactic Acid Production Platform Based on Lactobacillus saerimneri TBRC 5746
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Kitisak Sansatchanon , Pipat Sudying , Peerada Promdonkoy , Yutthana Kingcha , Wonnop Visessanguan , Sutipa Tanapongpipat , Weerawat Runguphan , Kanokarn Kocharin
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J. Microbiol. 2023;61(9):853-863. Published online September 14, 2023
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DOI: https://doi.org/10.1007/s12275-023-00077-x
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Abstract
- D-Lactic acid is a chiral, three-carbon organic acid, that bolsters the thermostability of polylactic acid. In this study, we
developed a microbial production platform for the high-titer production of D-lactic acid. We screened 600 isolates of lactic
acid bacteria (LAB) and identified twelve strains that exclusively produced D-lactic acid in high titers. Of these strains,
Lactobacillus saerimneri TBRC 5746 was selected for further development because of its homofermentative metabolism.
We investigated the effects of high temperature and the use of cheap, renewable carbon sources on lactic acid production and
observed a titer of 99.4 g/L and a yield of 0.90 g/g glucose (90% of the theoretical yield). However, we also observed L-lactic
acid production, which reduced the product’s optical purity. We then used CRISPR/dCas9-assisted transcriptional repression
to repress the two Lldh genes in the genome of L. saerimneri TBRC 5746, resulting in a 38% increase in D-lactic acid
production and an improvement in optical purity. This is the first demonstration of CRISPR/dCas9-assisted transcriptional
repression in this microbial host and represents progress toward efficient microbial production of D-lactic acid.
- Description of Luteibacter aegosomatis sp. nov., Luteibacter aegosomaticola sp. nov., and Luteibacter aegosomatissinici sp. nov. isolated from the Intestines of Aegosoma sinicum Larvae
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Hae-In Joe , Jee-Won Choi , June-Young Lee , Hojun Sung , Su-Won Jeong , Yun-Seok Jeong , Jae-Yun Lee , Jin-Woo Bae
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J. Microbiol. 2023;61(6):603-613. Published online May 5, 2023
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DOI: https://doi.org/10.1007/s12275-023-00051-7
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Abstract
- Three novel bacterial strains, 321T,
335T,
and 353T,
were isolated from the intestines of Aegosoma sinicum larvae collected
from Paju-Si, South Korea. The strains were Gram-negative, obligate aerobe and had rod-shaped cells with a single flagellum.
The three strains belonged to the genus Luteibacter in the family Rhodanobacteraceae and shared < 99.2% similarity
in their 16S rRNA gene sequence and < 83.56% similarity in thier whole genome sequence. Strains 321T,
335T,
and 353T
formed a monophyletic clade with Luteibacter yeojuensis KACC 11405T,
L. anthropi KACC 17855T,
and L. rhizovicinus
KACC 12830T,
with sequence similarities of 98.77–98.91%, 98.44–98.58%, and 97.88–98.02%, respectively. Further
genomic analyses, including the construction of the Up-to-date Bacterial Core Gene (UBCG) tree and assessment of other
genome-related indices, indicated that these strains were novel species belonging to the genus Luteibacter. All three strains
contained ubiquinone Q8 as their major isoprenoid quinone and iso-C15:0 and summed feature 9 (
C16:0 10-methyl and/or
iso-C17:1 ω9c) as their major cellular fatty acids. Phosphatidylethanolamine and diphosphatidylglycerol were the major polar
lipids in all the strains. The genomic DNA G + C contents of strains 321T,
335T,
and 353T
were 66.0, 64.5, and 64.5 mol%,
respectively. Based on multiphasic classification, strains 321T,
335T,
and 353T
were classified into the genus Luteibacter
as the type strains of novel species, for which the names Luteibacter aegosomatis sp. nov., Luteibacter aegosomaticola sp.
nov., and Luteibacter aegosomatissinici sp. nov. are proposed, respectively.
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