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Journal Article
- Delineating the Acquired Genetic Diversity and Multidrug Resistance in Alcaligenes from Poultry Farms and Nearby Soil.
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Abhilash Bhattacharjee, Anil Kumar Singh
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J. Microbiol. 2024;62(7):511-523. Published online June 21, 2024
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DOI: https://doi.org/10.1007/s12275-024-00129-w
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Abstract
- Alcaligenes faecalis is one of the most important and clinically significant environmental pathogens, increasing in importance due to its isolation from soil and nosocomial environments. The Gram-negative soil bacterium is associated with skin endocarditis, bacteremia, dysentery, meningitis, endophthalmitis, urinary tract infections, and pneumonia in patients. With emerging antibiotic resistance in A. faecalis, it has become crucial to understand the origin of such resistance genes within this clinically significant environmental and gut bacterium. In this research, we studied the impact of antibiotic overuse in poultry and its effect on developing resistance in A. faecalis. We sampled soil and faecal materials from five poultry farms, performed whole genome sequencing & analysis and identified four strains of A. faecalis. Furthermore, we characterized the genes in the genomic islands of A. faecalis isolates. We found four multidrug-resistant A. faecalis strains that showed resistance against vancomycin (MIC >1000 μg/ml), ceftazidime (50 μg/ml), colistin (50 μg/ml) and ciprofloxacin (50 μg/ml). From whole genome comparative analysis, we found more than 180 resistance genes compared to the reference sequence. Parts of our assembled contigs were found to be similar to different bacteria which included pbp1A and pbp2 imparting resistance to amoxicillin originally a part of Helicobacter and Bordetella pertussis. We also found the Mycobacterial insertion element IS6110 in the genomic islands of all four genomes. This prominent insertion element can be transferred and induce resistance to other bacterial genomes. The results thus are crucial in understanding the transfer of resistance genes in the environment and can help in developing regimes for antibiotic use in the food and poultry industry.
Review
- Genomic Evolution and Recombination Dynamics of Human Adenovirus D Species: Insights from Comprehensive Bioinformatic Analysis.
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Anyeseu Park, Chanhee Lee, Jeong Yoon Lee
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J. Microbiol. 2024;62(5):393-407. Published online March 7, 2024
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DOI: https://doi.org/10.1007/s12275-024-00112-5
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Abstract
- Human adenoviruses (HAdVs) can infect various epithelial mucosal cells, ultimately causing different symptoms in infected organ systems. With more than 110 types classified into seven species (A-G), HAdV-D species possess the highest number of viruses and are the fastest proliferating. The emergence of new adenovirus types and increased diversity are driven by homologous recombination (HR) between viral genes, primarily in structural elements such as the penton base, hexon and fiber proteins, and the E1 and E3 regions. A comprehensive analysis of the HAdV genome provides valuable insights into the evolution of human adenoviruses and identifies genes that display high variation across the entire genome to determine recombination patterns. Hypervariable regions within genetic sequences correlate with functional characteristics, thus allowing for adaptation to new environments and hosts. Proteotyping of newly emerging and already established adenoviruses allows for prediction of the characteristics of novel viruses. HAdV-D species evolved in a direction that increased diversity through gene recombination. Bioinformatics analysis across the genome, particularly in highly variable regions, allows for the verification or re-evaluation of recombination patterns in both newly introduced and pre-existing viruses, ultimately aiding in tracing various biological traits such as virus tropism and pathogenesis. Our research does not only assist in predicting the emergence of new adenoviruses but also offers critical guidance in regard to identifying potential regulatory factors of homologous recombination hotspots.
Journal Articles
- miR-135b Aggravates Fusobacterium nucleatum-Induced Cisplatin Resistance in Colorectal Cancer by Targeting KLF13
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Wei Zeng , Jia Pan , Guannan Ye
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J. Microbiol. 2024;62(2):63-73. Published online February 24, 2024
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DOI: https://doi.org/10.1007/s12275-023-00100-1
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Abstract
- Cisplatin resistance is the main cause of colorectal cancer (CRC) treatment failure, and the cause has been reported to be
related to Fusobacterium nucleatum (Fn) infection. In this study, we explored the role of Fn in regulating cisplatin resistance
of CRC cells and its underlying mechanism involved. The mRNA and protein expressions were examined by qRT-PCR
and western blot. Cell proliferation and cell apoptosis were assessed using CCK8 and flow cytometry assays, respectively.
Dual-luciferase reporter gene assay was adopted to analyze the molecular interactions. Herein, our results revealed that Fn
abundance and miR-135b expression were markedly elevated in CRC tissues, with a favorable association between the two.
Moreover, Fn infection could increase miR-135b expression via a concentration-dependent manner, and it also enhanced
cell proliferation but reduced apoptosis and cisplatin sensitivity by upregulating miR-135b. Moreover, KLF13 was proved
as a downstream target of miR-135b, of which overexpression greatly diminished the promoting effect of miR-135b or
Fn-mediated cisplatin resistance in CRC cells. In addition, it was observed that upstream 2.5 kb fragment of miR-135b
promoter could be interacted by β-catenin/TCF4 complex, which was proved as an effector signaling of Fn. LF3, a blocker
of β-catenin/TCF4 complex, was confirmed to diminish the promoting role of Fn on miR-135b expression. Thus, it could be
concluded that Fn activated miR-135b expression through TCF4/β-catenin complex, thereby inhibiting KLF13 expression
and promoting cisplatin resistance in CRC.
- Prevalence of Indigenous Antibiotic‑Resistant Salmonella Isolates and Their Application to Explore a Lytic Phage vB_SalS_KFSSM with an Intra‑Broad Specificity
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Jaein Choe , Su-Hyeon Kim , Ji Min Han , Jong-Hoon Kim , Mi-Sun Kwak , Do-Won Jeong , Mi-Kyung Park
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J. Microbiol. 2023;61(12):1063-1073. Published online January 2, 2024
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DOI: https://doi.org/10.1007/s12275-023-00098-6
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Abstract
- The consumption of fresh produce has led to increase in antibiotic-resistant (AR) Salmonella outbreaks. In this study, indigenous
Salmonella was isolated from a total of two hundred-two samples including fresh produce and agricultural environmental
samples in Korea. After biochemical confirmation using the Indole, Methyl Red, Voges-Proskauer, Citrate tests, presumable
Salmonella isolates were identified by 16S rRNA sequencing. Identified Salmonella isolates were evaluated for antibiotic
susceptibility against twenty-two antibiotics. The specificity and the efficiency of plating (EOP) of vB_SalS_KFSSM were
evaluated against fifty-three bacterial strains. Twenty-five suspected Salmonella were isolated and confirmed by the positive
result
for methyl red and citrate, of which ten were identified as Salmonella spp. through 16S rRNA gene sequencing. Eight
Salmonella isolates (4.0%, n = 8/202) were resistant to at least one antibiotic, among which five were multi-drug resistant. As
a lytic phage against Salmonella spp. CMGS-1, vB_SalS_KFSSM was isolated from cow manure. The phage was observed as
a tailed phage belonging to the class Caudoviricetes. It exhibited an intra-broad specificity against four indigenous AR Salmonella
isolates, two indigenous Salmonella isolates, and five other Salmonella serotypes with great efficiencies (EOP ≥ 0.75).
Thus, this study suggested the potential of vB_SalS_KFSSM to combat indigenous AR Salmonella.
- 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.
- The β‑Lactamase Activity at the Community Level Confers β‑Lactam Resistance to Bloom‑Forming Microcystis aeruginosa Ce
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Yerim Park , Wonjae Kim , Minkyung Kim , Woojun Park
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J. Microbiol. 2023;61(9):807-820. Published online October 18, 2023
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DOI: https://doi.org/10.1007/s12275-023-00082-0
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Abstract
- Many freshwater cyanobacteria, including Microcystis aeruginosa, lack several known antibiotic resistance genes; however,
both axenic and xenic M. aeruginosa strains exhibited high antibiotic resistance against many antibiotics under our tested
concentrations, including colistin, trimethoprim, and kanamycin. Interestingly, axenic PCC7806, although not the xenic
NIBR18 and NIBR452 strains, displayed susceptibility to ampicillin and amoxicillin, indicating that the associated bacteria
in the phycosphere could confer such antibiotic resistance to xenic strains. Fluorescence and scanning electron microscopic
observations revealed their tight association, leading to possible community-level β-lactamase activity. Combinatory treatment
of ampicillin with a β-lactamase inhibitor, sulbactam, abolished the ampicillin resistance in the xenic stains. The
nitrocefin-based assay confirmed the presence of significant community-level β-lactamase activity. Our tested low ampicillin
concentration and high β-lactamase activity could potentially balance the competitive advantage of these dominant species
and provide opportunities for the less competitive species, thereby resulting in higher bacterial diversity under ampicillin
treatment conditions. Non-PCR-based metagenome data from xenic NIBR18 cultures revealed the dominance of blaOXArelated
antibiotic resistance genes followed by other class A β-lactamase genes (AST-1 and FAR-1). Alleviation of ampicillin
toxicity could be observed only in axenic PCC7806, which had been cocultured with β-lactamase from other freshwater
bacteria. Our study suggested M. aeruginosa develops resistance to old-class β-lactam antibiotics through altruism, where
associated bacteria protect axenic M. aeruginosa cells.
- 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.
Review
- Influence of Microbiota on Vaccine Effectiveness: “Is the Microbiota the Key to Vaccine‑induced Responses?”
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So-Hee Hong
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J. Microbiol. 2023;61(5):483-494. Published online April 13, 2023
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DOI: https://doi.org/10.1007/s12275-023-00044-6
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Abstract
- Vaccines are one of the most powerful tools for preventing infectious diseases. To effectively fight pathogens, vaccines should
induce potent and long-lasting immune responses that are specific to the pathogens. However, not all vaccines can induce
effective immune responses, and the responses vary greatly among individuals and populations. Although several factors, such
as age, host genetics, nutritional status, and region, affect the effectiveness of vaccines, increasing data have suggested that
the gut microbiota is critically associated with vaccine-induced immune responses. In this review, I discuss how gut microbiota
affects vaccine effectiveness based on the clinical and preclinical data, and summarize possible underlying mechanisms
related to the adjuvant effects of microbiota. A better understanding of the link between vaccine-induced immune responses
and the gut microbiota using high-throughput technology and sophisticated system vaccinology approaches could provide
crucial insights for designing effective personalized preventive and therapeutic vaccination strategies.
Journal Articles
- Microbial metabolic responses and CO2 emissions differentiated by soil water content variation in subarctic tundra soils
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Dockyu Kim , Namyi Chae , Mincheol Kim , Sungjin Nam , Tai Kyoung Kim , Ki-Tea Park , Bang Yong Lee , Eungbin Kim , Hyoungseok Lee
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J. Microbiol. 2022;60(12):1130-1138. Published online November 24, 2022
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DOI: https://doi.org/10.1007/s12275-022-2378-3
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Abstract
- Recent rapid air temperature increases across the northernlatitude
tundra have prolonged permafrost thawing and snow
melting periods, resulting in increased soil temperature (Ts)
and volumetric soil water content (SWC). Under prolonged
soil warming at 8°C, Alaskan tundra soils were incubated in
a microcosm system and examined for the SWC differential
influence on the microbial decomposition activity of large
molecular weight (MW) humic substances (HS). When one
microcosm soil (AKC1-1) was incubated at a constant SWC
of 41% for 90 days (T = 90) and then SWC was gradually
decreased from 41% to 29% for another T = 90, the initial
HS was partly depolymerized. In contrast, in AKC1-2 incubated
at a gradually decreasing SWC from the initial 32% to
10% for T = 90 and then increasing to 27% for another T =
90, HS depolymerization was undetected. Overall, the microbial
communities in AKC1-1 could maintain metabolic
activity at sufficient and constant SWC during the initial T =
90 incubation. In contrast, AKC1-2 microbes may have been
damaged by drought stress during the drying SWC regimen,
possibly resulting in the loss of HS decomposition activity,
which did not recover even after re-wetting to an optimal
SWC range (20–40%). After T = 90, the CO2 production in
both treatments was attributed to the increased decomposition
of small-MW organic compounds (including aerobic
HS-degradative products) within an optimal SWC range. We
expect this study to provide new insights into the early effects
of warming- and topography-induced SWC variations on
the microbial contribution to CO2 emissions via HS decomposition
in northern-latitude tundra soil.
- Fus3 and Tpk2 protein kinases regulate the phosphorylation-dependent functions of RNA helicase Dhh1 in yeast mating and Ste12 protein expression
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Jaehee Hwang , Daehee Jung , Jinmi Kim
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J. Microbiol. 2022;60(8):843-848. Published online July 14, 2022
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DOI: https://doi.org/10.1007/s12275-022-2213-x
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Abstract
- Decapping of mRNA is a key regulatory step for mRNA decay
and translation. The RNA helicase, Dhh1, is known as a
decapping activator and translation repressor in yeast Saccharomyces
cerevisiae. Dhh1 also functions as a gene-specific
positive regulator in the expression of Ste12, a mating-specific
transcription factor. A previous study showed that the Nerminal
phosphorylation of Dhh1 regulates its association
with the mRNA-binding protein, Puf6, to affect the protein
translation of Ste12. Here, we investigated the roles of the
phosphorylated residues of Dhh1 in yeast mating process and
Ste12 expression. The phospho-deficient mutation, DHH1-
T10A, was associated with decreased diploid formation during
mating and decreased level of the Ste12 protein in response
to α-mating pheromone. A kinase overexpression analysis
revealed that Ste12 protein expression was affected by
overexpression of Fus3 MAP kinase or Tpk2 kinase. Tpk2
was shown to be responsible for phosphorylation of Dhh1 at
Thr10. Our study shows that overexpression of Fus3 or Tpk2
alters the Dhh1-Puf6 protein interaction and thereby affects
Ste12 protein expression.
- Characterization of antibiotic-resistant, coagulase-negative staphylococci from fresh produce and description of Staphylococcus shinii sp. nov. isolated from chives
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Gyu-Sung Cho , Bo Li , Erik Brinks , Charles , M.A.P. Franz
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J. Microbiol. 2022;60(9):877-889. Published online June 22, 2022
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DOI: https://doi.org/10.1007/s12275-022-2100-5
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Abstract
- Coagulase-negative Staphylococcus (CoNS) species may possess
antibiotic resistance genes and have been associated with
nosocomial infections. In this study, 91 CoNS with decreased
susceptibility to oxacillin were isolated from fresh produce
using oxacillin containing agar plates. Their antibiotic resistances
were determined phenotypically and all isolates were
identified by rep-PCR, 16S rRNA and rpoB gene sequencing.
Furthermore, the genomes of representative strains were sequenced
in order to confirm species identification by phylogenomics.
The majority (64 of 91) of the CoNS strains could
be identified as Mammaliicoccus (M.) fleurettii, while 13 were
identified as M. sciuri, 8 as M. vitulinus, 2 as Staphylococcus
(S.) epidermidis and single strains each as S. warneri, S. xylosus,
Staphylococcus spp. and S. casei. Most of the strains were generally
susceptible to clinically-relevant antibiotics, but only
few (< 7%) strains possessed multiple resistances. Both oxacillin
and cefoxitin resistant isolates were considered to be
presumptive methicillin-resistant CoNS. From whole genome
sequencing data of 6 representative strains, the mecA gene,
accessory genes and the SCC loci were compared, which revealed
high variability between some of the strains. The major
fatty acids of K22-5MT strain included anteiso-C15:0,
iso-C15:0, iso-C17:0, anteiso-C17:0, C18:0, and C20:0. Average nucleotide
identity and digital DNA-DNA hybridization values
indicated that Staphylococcus strain K22-5MT was below the
species delineation cutoff values for ANI (less than 91%) and
DDH (less than 44.4%), with the most closely related species
being the S. pseudoxylosus S04009T type strain. Thus, strain
K22- 5MT (=DSM 112532T, =LMG 32324T) represents a novel
species, for which the name Staphylococcus shinii sp. nov. is
proposed.
Meta-Analysis
- Proposal of a health gut microbiome index based on a meta-analysis of Korean and global population datasets
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Hyun-Seok Oh , Uigi Min , Hyejin Jang , Namil Kim , Jeongmin Lim , Mauricio Chalita , Jongsik Chun
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J. Microbiol. 2022;60(5):533-549. Published online March 31, 2022
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DOI: https://doi.org/10.1007/s12275-022-1526-0
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Abstract
- The disruption of the human gut microbiota has been linked
to host health conditions, including various diseases. However,
no reliable index for measuring and predicting a healthy microbiome
is currently available. Here, the sequencing data of
1,663 Koreans were obtained from three independent studies.
Furthermore, we pooled 3,490 samples from public databases
and analyzed a total of 5,153 fecal samples. First, we analyzed
Korean gut microbiome covariates to determine the influence
of lifestyle on variation in the gut microbiota. Next, patterns
of microbiota variations across geographical locations and
disease statuses were confirmed using a global cohort and disease
data. Based on comprehensive comparative analysis, we
were able to define three enterotypes among Korean cohorts,
namely, Prevotella type, Bacteroides type, and outlier type.
By a thorough categorization of dysbiosis and the evaluation
of microbial characteristics using multiple datasets, we identified
a wide spectrum of accuracy levels in classifying health
and disease states. Using the observed microbiome patterns,
we devised an index named the gut microbiome index (GMI)
that could consistently predict health conditions from human
gut microbiome data. Compared to ecological metrics, the
microbial marker index, and machine learning approaches,
GMI distinguished between healthy and non-healthy individuals
with a higher accuracy across various datasets. Thus,
this study proposes a potential index to measure health status
of gut microbiome that is verified from multiethnic data
of various diseases, and we expect this model to facilitate further
clinical application of gut microbiota data in future.
Journal Articles
- Evaluation of Cyc1 protein stability in Acidithiobacillus ferrooxidans bacterium after E121D mutation by molecular dynamics simulation to improve electron transfer
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Mahnaz Shojapour , Somayeh Farahmand , Faezeh Fatemi , Marzieh Dehghan Shasaltaneh
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J. Microbiol. 2022;60(5):526-532. Published online March 14, 2022
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DOI: https://doi.org/10.1007/s12275-022-1645-7
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Abstract
- Cyc1 (Cytochrome c552) is a protein in the electron transport
chain of the Acidithiobacillus ferrooxidans (Af) bacteria which
obtain their energy from oxidation Fe2+ to Fe3+. The electrons
are directed through Cyc2, RCY (rusticyanin), Cyc1, and Cox
aa3 proteins to O2. Cyc1 protein consists of two chains, A and
B. In the present study, a novel mutation (E121D) in the A
chain of Cyc1 protein was selected due to electron receiving
from Histidine 143 of RCY. Then, the changes performed in
the E121D mutant were evaluated by MD simulations analyzes.
Cyc1 and RCY proteins were docked by a Patchdock
server. By E121D mutation, the connection between Zn 1388
of chain B and aspartate 121 of chain A weaken. Asp 121 gets
farther from Zn 1388. Therefore, the aspartate gets closer to
Cu 1156 of the RCY leading to the higher stability of the RCY/
Cyc1 complex. Further, an acidic residue (Glu121) becomes
a more acidic residue (Asp121) and improves the electron
transfer to Cyc1 protein. The results of RMSF analysis showed
further ligand flexibility in mutation. This leads to fluctuation
of the active site and increases redox potential at the mutation
point and the speed of electron transfer. This study also
predicts that in all respiratory chain proteins, electrons probably
enter the first active site via glutamate and exit histidine
in the second active site of each respiratory chain protein.
- Cytophaga hutchinsonii chu_2177, encoding the O-antigen ligase, is essential for cellulose degradation
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Yahong Tan , Wenxia Song , Lijuan Gao , Weican Zhang , Xuemei Lu
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J. Microbiol. 2022;60(4):364-374. Published online January 7, 2022
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DOI: https://doi.org/10.1007/s12275-022-1531-3
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Abstract
- Cytophaga hutchinsonii can efficiently degrade crystalline
cellulose, in which the cell surface cellulases secreted by the
type IX secretion system (T9SS) play important roles, but
the degradation mechanism remains unclear, and the anchor
mechanism of cellulases on the outer membrane in C.
hutchinsonii has not been studied. Here, chu_2177 was identified
by transposon mutagenesis and was proved to be indispensable
for cellulose utilization in C. hutchinsonii. Disruption
of chu_2177 resulted in O-antigen deficiency and chu_
177 could confer O-antigen ligase activity upon an Escherichia
coli waal mutant, indicating that chu_2177 encoded the Ontigen
ligase. Moreover, deletion of chu_2177 caused defects
in cellulose utilization, cell motility, biofilm formation, and
stress resistance. Further study showed that the endoglucanase
activity was markedly decreased in the outer membrane
but was increased in the culture fluid without chu_2177.
Western blot proved that endoglucanase CHU_1336 was not
located on the outer membrane but was released in the culture
fluid of the Δ2177 mutant. Further proteomics analysis
showed that many cargo proteins of T9SS were missing in
the outer membrane of the Δ2177 mutant. Our study revealed
that the deletion of chu_2177 affected the localization of
many T9SS cargo proteins including cellulases on the outer
membrane of C. hutchinsonii.
- Changpingibacter yushuensis gen. nov., sp. nov., isolated from fluvial sediment in Qinghai Tibet Plateau of China
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Yifan Jiao , Sihui Zhang , Jing Yang , Xin-He Lai , Kui Dong , Yanpeng Cheng , Mingchao Xu , Wentao Zhu , Shan Lu , Dong Jin , Ji Pu , Ying Huang , Liyun Liu , Suping Wang , Jianguo Xu
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J. Microbiol. 2022;60(2):147-155. Published online January 7, 2022
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DOI: https://doi.org/10.1007/s12275-022-1199-8
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Abstract
- Two facultatively anaerobic, short rod-shaped, non-motile,
Gram-stain-positive, unknown bacterial strains (JY-X040T
and JY-X174) were isolated from fluvial sediments of Tongtian
River in Yushu Tibetan Autonomous Prefecture, Qinghai
province, China. Cells formed translucent, gray, round and
convex colonies, with a diameter of less than 0.5 mm after 5
days of incubation at 30°C on brain heart infusion-5% sheep
blood agar. The 16S rRNA gene sequence similarity between
strain JY-X040T and Fudania jinshanensis 313T is 93.87%.
In the four phylogenetic trees constructed based on the 16S
rRNA gene and 423 core genes, the two isolates form an independent
branch, phylogenetically closest to F. jinshanensis
313T, but could not be classified as a member of the genus
Fudania or any other genus of the family Arcanobacteriaceae.
The DNA G + C content of strain JY-X040T was 57.8%. Calculation
results
of average nucleotide identity, digital DNADNA
hybridization value and amino acid identity between
strain JY-X040T and F. jinshanensis 313T are 69.9%, 22.9%,
and 64.1%. The major cellular fatty acids were C16:0 (23%)
and C18:1ω9c (22%). The cell-wall peptidoglycan type was A5α
(L-Lys-L-Ala-L-Lys-D-Glu). The polar lipids comprised diphosphatidylglycerol,
phosphatidylglycerol, phosphatidylinositol,
phosphatidylinositol mannoside and four unidentified components.
The whole-cell sugars contained rhamnose and ribose.
MK-10(H4) was the sole respiratory quinone. The minimum
inhibitory concentration of streptomycin was 32 μg/ml. All
physiological, biochemical, chemotaxonomic and genomic
characteristics support that strains JY-X040T and JY-X174
represent members of a novel species in a new genus, Changpingibacter
yushuensis gen. nov., sp. nov. The type strain is
JY-X040T (GDMCC 1.1996T = KCTC 49514T).
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