1.Change of bacterial community structure during cellulose degradation by the microbial consortium.
Shiqi AI ; Yiquan ZHAO ; Zhiyuan SUN ; Yamei GAO ; Lei YAN ; Hongzhi TANG ; Weidong WANG
Chinese Journal of Biotechnology 2018;34(11):1794-1808
In order to clarify dynamic change of microbial community composition and to identify key functional bacteria in the cellulose degradation consortium, we studied several aspects of the biodegradation of filter papers and rice straws by the microbial consortium, the change of substrate degradation, microbial biomass and pH of fermentation broth. We extracted total DNA of the microbial consortium in different degradation stages for high-throughput sequencing of amplicons of bacterial 16 S rRNA genes. Based on the decomposition characteristics test, we defined the 12th, 72nd and 168th hours after inoculation as the initial stage, peak stage and end stage of degradation, respectively. The microbial consortium was mainly composed of 1 phylum, 2 classes, 2 orders, 7 families and 11 genera. With cellulose degradation, bacteria in the consortium showed different growth trends. The relative abundance of Brevibacillus and Caloramator decreased gradually. The relative abundance of Clostridium, Bacillus, Geobacillus and Cohnella increased gradually. The relative abundance of Ureibacillus, Tissierella, Epulopiscium was the highest in peak stage. The relative abundance of Paenibacillus and Ruminococcus did not change obviously in each stage. Above-mentioned 11 main genera all belonged to Firmicutes, which are thermophilic, broad pH adaptable and cellulose or hemicellulose degradable. During cellulose degradation by the microbial consortium, aerobic bacteria were dominant functional bacteria in the initial stage. However, the relative abundance of anaerobic bacteria increased gradually in middle and end stage, and replaced aerobic bacteria to become main bacteria to degrade cellulose.
Bacteria
;
classification
;
metabolism
;
Biodegradation, Environmental
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Cellulose
;
metabolism
;
DNA, Bacterial
;
genetics
;
Microbial Consortia
;
RNA, Ribosomal, 16S
;
genetics
2.ToxR Is Required for Biofilm Formation and Motility of Vibrio Parahaemolyticus.
Long CHEN ; Yue QIU ; Hao TANG ; Ling Fei HU ; Wen Hui YANG ; Xiao Jue ZHU ; Xin Xiang HUANG ; Tang WANG ; Yi Quan ZHANG
Biomedical and Environmental Sciences 2018;31(11):848-850
Bacterial Proteins
;
genetics
;
metabolism
;
Biofilms
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DNA-Binding Proteins
;
genetics
;
metabolism
;
Flagella
;
genetics
;
metabolism
;
Gene Expression Regulation, Bacterial
;
Transcription Factors
;
genetics
;
metabolism
;
Vibrio parahaemolyticus
;
cytology
;
genetics
;
growth & development
;
physiology
3.First Case Report of Bacteremia Due to Catabacter hongkongensis in a Korean Patient.
Yong Jun CHOI ; Eun Jeong WON ; Soo Hyun KIM ; Myung Geun SHIN ; Jong Hee SHIN ; Soon Pal SUH
Annals of Laboratory Medicine 2017;37(1):84-87
No abstract available.
Aged
;
Anti-Bacterial Agents/pharmacology/therapeutic use
;
Cefotaxime/analogs & derivatives/therapeutic use
;
Cholangiopancreatography, Endoscopic Retrograde
;
Gallstones/surgery
;
Gram-Negative Anaerobic Bacteria/drug effects/genetics/*isolation & purification
;
Gram-Negative Bacterial Infections/*diagnosis/drug therapy/microbiology
;
Humans
;
Male
;
Metronidazole/therapeutic use
;
Microbial Sensitivity Tests
;
RNA, Ribosomal, 16S/chemistry/genetics/metabolism
;
Sequence Analysis, DNA
;
Tomography, X-Ray Computed
4.Susceptibility of Ceftolozane-Tazobactam and Ceftazidime-Avibactam Against a Collection of β-Lactam-Resistant Gram-Negative Bacteria.
Mark D GONZALEZ ; Allison R MCMULLEN ; Meghan A WALLACE ; Matthew P CROTTY ; David J RITCHIE ; Carey Ann D BURNHAM
Annals of Laboratory Medicine 2017;37(2):174-176
No abstract available.
Anti-Bacterial Agents/*pharmacology
;
Azabicyclo Compounds/*pharmacology
;
Bacterial Proteins/genetics
;
Ceftazidime/*pharmacology
;
Cephalosporins/*pharmacology
;
DNA, Bacterial/genetics/metabolism
;
Drug Resistance, Bacterial/*drug effects
;
Gram-Negative Bacteria/drug effects/*isolation & purification
;
Humans
;
Microbial Sensitivity Tests
;
Penicillanic Acid/*analogs & derivatives/pharmacology
;
Pseudomonas aeruginosa/drug effects/isolation & purification
;
Real-Time Polymerase Chain Reaction
5.Structural insights into glutathione-mediated activation of the master regulator PrfA in Listeria monocytogenes.
Yong WANG ; Han FENG ; Yalan ZHU ; Pu GAO
Protein & Cell 2017;8(4):308-312
Bacterial Proteins
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chemistry
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genetics
;
metabolism
;
DNA, Bacterial
;
chemistry
;
genetics
;
metabolism
;
Gene Expression Regulation, Bacterial
;
physiology
;
Glutathione
;
metabolism
;
Listeria monocytogenes
;
chemistry
;
genetics
;
metabolism
;
Peptide Termination Factors
;
chemistry
;
genetics
;
metabolism
6.Activation of NF-κB and AP-1 Mediates Hyperproliferation by Inducing β-Catenin and c-Myc in Helicobacter pylori-Infected Gastric Epithelial Cells.
Eunyoung BYUN ; Bohye PARK ; Joo Weon LIM ; Hyeyoung KIM
Yonsei Medical Journal 2016;57(3):647-651
PURPOSE: In the gastric mucosa of Helicobacter pylori (H. pylori)-infected patients with gastritis or adenocarcinoma, proliferation of gastric epithelial cells is increased. Hyperproliferation is related to induction of oncogenes, such as β-catenin and c-myc. Even though transcription factors NF-κB and AP-1 are activated in H. pylori-infected cells, whether NF-κB or AP-1 regulates the expression of β-catenein or c-myc in H. pylori-infected cells has not been clarified. The present study was undertaken to investigate whether H. pylori-induced activation of NF-κB and AP-1 mediates the expression of oncogenes and hyperproliferation of gastric epithelial cells. MATERIALS AND METHODS: Gastric epithelial AGS cells were transiently transfected with mutant genes for IκBα (MAD3) and c-Jun (TAM67) or treated with a specific NF-κB inhibitor caffeic acid phenethyl ester (CAPE) or a selective AP-1 inhibitor SR-11302 to suppress activation of NF-κB or AP-1, respecively. As reference cells, the control vector pcDNA was transfected to the cells. Wild-type cells or transfected cells were cultured with or without H. pylori. RESULTS: H. pylori induced activation of NF-κB and AP-1, cell proliferation, and expression of oncogenes (β-catenein, c-myc) in AGS cells, which was inhibited by transfection of MAD3 and TAM67. Wild-type cells and the cells transfected with pcDNA showed similar activities of NF-κB and AP-1, proliferation, and oncogene expression regardless of treatment with H. pylori. Both CAPE and SR-11302 inhibited cell proliferation and expression of oncogenes in H. pylori-infected cells. CONCLUSION: H. pylori-induced activation of NF-κB and AP-1 regulates transcription of oncogenes and mediates hyperproliferation in gastric epithelial cells.
Blotting, Western
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Caffeic Acids
;
Cell Line, Tumor
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Cell Proliferation
;
DNA, Bacterial/analysis/genetics
;
DNA-Binding Proteins/*metabolism
;
Epithelial Cells/*metabolism
;
Gastric Mucosa/*metabolism/pathology
;
Gastritis/pathology
;
Gene Expression Regulation, Bacterial
;
Helicobacter Infections/metabolism/pathology/physiopathology
;
Helicobacter pylori/pathogenicity/physiology
;
Humans
;
NF-kappa B/antagonists & inhibitors/*biosynthesis/metabolism
;
Peptide Fragments
;
Phenylethyl Alcohol/analogs & derivatives
;
Proto-Oncogene Proteins c-jun
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Repressor Proteins
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Transcription Factor AP-1/*biosynthesis
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Transcription Factors/*metabolism
;
beta Catenin/*metabolism
7.Markerless DNA deletion based on Red recombination and in vivo I-Sec I endonuclease cleavage in Escherichia coli chromosome.
Meiqin ZHU ; Jian YU ; Changlin ZHOU ; Hongqing FANG
Chinese Journal of Biotechnology 2016;32(1):114-126
Red-based recombineering has been widely used in Escherichia coli genome modification through electroporating PCR fragments into electrocompetent cells to replace target sequences. Some mutations in the PCR fragments may be brought into the homologous regions near the target. To solve this problem in markeless gene deletion we developed a novel method characterized with two-step recombination and a donor plasmid. First, generated by PCR a linear DNA cassette which comprises a I-Sec I site-containing marker gene and homologous arms was electroporated into cells for marker-substitution deletion of the target sequence. Second, after a donor plasmid carrying the I-Sec I site-containing fusion homologous arm was chemically transformed into the marker-containing cells, the fusion arms and the marker was simultaneously cleaved by I-Sec I endonuclease and the marker-free deletion was stimulated by double-strand break-mediated intermolecular recombination. Eleven nonessential regions in E. coli DH1 genome were sequentially deleted by our method, resulting in a 10.59% reduced genome size. These precise deletions were also verified by PCR sequencing and genome resequencing. Though no change in the growth rate on the minimal medium, we found the genome-reduced strains have some alteration in the acid resistance and for the synthesis of lycopene.
Chromosomes, Bacterial
;
genetics
;
DNA
;
Endonucleases
;
metabolism
;
Escherichia coli
;
genetics
;
Genetic Engineering
;
methods
;
Recombination, Genetic
;
Sequence Deletion
8.First Case Report of Human Infection With Ochrobactrum tritici Causing Bacteremia and Cholecystitis.
Duck Jin HONG ; Keon Han KIM ; Jung Ok KIM ; Jun Sung HONG ; Seok Hoon JEONG ; Kyungwon LEE
Annals of Laboratory Medicine 2016;36(3):278-280
No abstract available.
Aged
;
Anti-Bacterial Agents/pharmacology/therapeutic use
;
Bacteremia/blood/*diagnosis/microbiology
;
C-Reactive Protein/analysis
;
Cholecystitis/blood/cerebrospinal fluid/microbiology
;
Electrophoresis, Gel, Pulsed-Field
;
Enterococcus faecium/drug effects/isolation & purification/metabolism
;
Humans
;
Male
;
Microbial Sensitivity Tests
;
Microscopy, Electron, Scanning
;
Ochrobactrum/drug effects/isolation & purification/*metabolism
;
RNA, Ribosomal, 16S/analysis/genetics/metabolism
;
Sequence Analysis, DNA
;
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
9.Septicemia Caused by Neisseria meningitidis With Decreased Ciprofloxacin Susceptibility: The First Case Report in Korea.
Ji Yeon AHN ; Joon Ki MIN ; Myeong Hee KIM ; Soo Youn MOON ; Ki Ho PARK ; Mi Suk LEE ; Jun Seong SON
Annals of Laboratory Medicine 2016;36(3):275-277
No abstract available.
Anti-Bacterial Agents/pharmacology
;
Bacterial Proteins/genetics
;
Ceftriaxone/pharmacology/therapeutic use
;
Ciprofloxacin/pharmacology/therapeutic use
;
DNA, Bacterial/analysis/metabolism
;
Disk Diffusion Antimicrobial Tests
;
*Drug Resistance, Bacterial
;
Female
;
Humans
;
Neisseria meningitidis/drug effects/genetics/*isolation & purification
;
Polymerase Chain Reaction
;
Sepsis/*diagnosis/drug therapy/microbiology
;
Transcription Factors/genetics
;
Young Adult
10.Prevalence of Major Methicillin-Resistant Staphylococcus aureus Clones in Korea Between 2001 and 2008.
Gi Su KANG ; Yung Hee JUNG ; Hwa Su KIM ; Yeong Seon LEE ; Chan PARK ; Kwang Jun LEE ; Jeong Ok CHA
Annals of Laboratory Medicine 2016;36(6):536-541
BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) are important pathogens causing nosocomial infections in Korean hospitals. This study aimed to investigate the epidemiological and genetic diversity of clinical S. aureus isolates in healthcare settings from 2001 to 2008. METHODS: Samples and data were obtained from 986 individuals as part of the National Antimicrobial Surveillance Project, involving 10 regions nationwide. Molecular typing studies, including multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing were performed, and a representative clone of Korean MRSA was classified by combinational grouping using a DiversiLab (DL; bioMérieux, France) repetitive element polymerase chain reaction (rep-PCR) system. RESULTS: Nine Korean MRSA clones (KMRSA-1 to -9) were identified by analysis of genetic backgrounds and molecular characteristics. KMRSA-1 to -3, expressing clonal complex (CC) 5 (carrying SCCmec II), CC8 (carrying SCCmec III), and CC72 (carrying SCCmec IV) were spread nationwide. In contrast, KMRSA-6 was highly prevalent in Gyeongsangnam-do, and KMRSA-4 was highly prevalent in Jeollanam-do and Jeollabuk-do. CONCLUSIONS: Epidemic KMRSA clones were genetically similar to major clones identified from the USA, with the exception of KMRSA-2, which had the SCCmec III type. Our results provide important insights into the distribution and molecular genetics of MRSA strains in Korea and may aid in the monitoring of MRSA spread throughout the country.
Bacterial Proteins/genetics
;
DNA, Bacterial/genetics/metabolism
;
Electrophoresis, Gel, Pulsed-Field
;
Hospitals
;
Humans
;
Methicillin-Resistant Staphylococcus aureus/*genetics/isolation & purification
;
Multilocus Sequence Typing
;
Multiplex Polymerase Chain Reaction
;
Prevalence
;
Republic of Korea/epidemiology
;
Staphylococcal Infections/diagnosis/*epidemiology/microbiology

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