Journal of Microbiology

Journal Article

In Silico Intensive Analysis for the E4 Gene Evolution of Human Adenovirus Species D.: Chanhee Lee, Anyeseu Park, Jeong Yoon Lee; J. Microbiol. 2024;62(5):409-418. Published online April 30, 2024; DOI: https://doi.org/10.1007/s12275-024-00132-1

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Abstract: Adenovirus (Ad) is a ubiquitous pathogen capable of infecting a wide range of animals and humans. Human Adenovirus (HAdV) can cause severe infection, particularly in individuals with compromised immune systems. To date, over 110 types of HAdV have been classified into seven species from A to G, with the majority belonging to the human adenovirus species D (HAdV-D). In the HAdV-D, the most significant factor for the creation of new adenovirus types is homologous recombination between viral genes involved in determining the virus tropism or evading immune system of host cells. The E4 gene, consisting of seven Open Reading Frames (ORFs), plays a role in both the regulation of host cell metabolism and the replication of viral genes. Despite long-term studies, the function of each ORF remains unclear. Based on our updated information, ORF2, ORF3, and ORF4 have been identified as regions with relatively high mutations compared to other ORFs in the E4 gene, through the use of in silico comparative analysis. Additionally, we managed to visualize high mutation sections, previously undetectable at the DNA level, through a powerful amino acid sequence analysis tool known as proteotyping. Our research has revealed the involvement of the E4 gene in the evolution of human adenovirus, and has established accurate sequence information of the E4 gene, laying the groundwork for further research.

Review

Genomic Evolution and Recombination Dynamics of Human Adenovirus D Species: Insights from Comprehensive Bioinformatic Analysis.: Anyeseu Park, Chanhee Lee, Jeong Yoon Lee; J. Microbiol. 2024;62(5):393-407. Published online March 7, 2024; DOI: https://doi.org/10.1007/s12275-024-00112-5

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1 Citations

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

Prevalence of Indigenous Antibiotic‑Resistant Salmonella Isolates and Their Application to Explore a Lytic Phage vB_SalS_KFSSM with an Intra‑Broad Specificity: Jaein Choe , Su-Hyeon Kim , Ji Min Han , Jong-Hoon Kim , Mi-Sun Kwak , Do-Won Jeong , Mi-Kyung Park; J. Microbiol. 2023;61(12):1063-1073. Published online January 2, 2024; 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.

Evidence of the genetic diversity and clonal population structure of Oenococcus oeni strains isolated from different wine-making regions of China: Dongliang Yu , Kan Shi , Xiangyuan Wen , Fangshu Xie , Tao Wang , Shuwen Liu , Ling He; J. Microbiol. 2018;56(8):556-564. Published online July 25, 2018; DOI: https://doi.org/10.1007/s12275-018-7568-7

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5 Citations

Abstract: Studies of the genetic diversity and population structure of Oenococcus oeni (O. oeni) strains from China are lacking compared to other countries and regions. In this study, amplified fragment length polymorphism (AFLP) and multilocus sequence typing (MLST) methods were used to investigate the genetic diversity and regional evolutionary patterns of 38 O. oeni strains isolated from different wine-making regions in China. The results indicated that AFLP was markedly more efficient than MLST for typing O. oeni strains. AFLP distinguished 37 DNA patterns compared to 7 sequence types identified using MLST, corresponding to discriminatory indices of 0.999 and 0.602, respectively. The AFLP results revealed a high level of genetic diversity among the O. oeni strains from different regions of China, since two subpopulations and an intraspecific homology higher than 60% were observed. Phylogenetic analysis of the O. oeni strains using the MLST method also identified two major phylogroups, which were differentiated into two distinct clonal complexes by minimum spanning tree analysis. Neither intragenic nor intergenic recombination verified the existence of the clonal population structure of the O. oeni strains.

Reviews

MINIREVIEW] Importance of differential identification of Mycobacterium tuberculosis strains for understanding differences in their prevalence, treatment efficacy, and vaccine development: Hansong Chae , Sung Jae Shin; J. Microbiol. 2018;56(5):300-311. Published online May 2, 2018; DOI: https://doi.org/10.1007/s12275-018-8041-3

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22 Citations

Abstract: Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a serious global health problem in the 21st century because of its high mortality. Mtb is an extremely successful human-adapted pathogen that displays a multifactorial ability to control the host immune response and to evade killing by drugs, resulting in the breakdown of BCG vaccine-conferred anti-TB immunity and development of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mtb. Although genetic components of the genomes of the Mtb complex strains are highly conserved, showing over 99% similarity to other bacterial genera, recently accumulated evidence suggests that the genetic diversity of the Mtb complex strains has implications for treatment outcomes, development of MDR/XDR Mtb, BCG vaccine efficacy, transmissibility, and epidemiological outbreaks. Thus, new insights into the pathophysiological features of the Mtb complex strains are required for development of novel vaccines and for control of MDR/XDR Mtb infection, eventually leading to refinement of treatment regimens and the health care system. Many studies have focused on the differential identification of Mtb complex strains belonging to different lineages because of differences in their virulence and geographical dominance. In this review, we discuss the impact of differing genetic characteristics among Mtb complex strains on vaccine efficacy, treatment outcome, development of MDR/ XDR Mtb strains, and epidemiological outbreaks by focusing on the best-adapted human Mtb lineages. We further explore the rationale for differential identification of Mtb strains for more effective control of TB in clinical and laboratory settings by scrutinizing current diagnostic methods.

MINIREVIEW] Rapid and robust MALDI-TOF MS techniques for microbial identification: a brief overview of their diverse applications: Kyoung-Soon Jang , Young Hwan Kim; J. Microbiol. 2018;56(4):209-216. Published online February 28, 2018; DOI: https://doi.org/10.1007/s12275-018-7457-0

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104 Citations

Abstract: Advances in mass spectrometry have enabled the investigation of various biological systems by directly analyzing diverse sets of biomolecules (i.e., proteins, lipids, and carbohydrates), thus making a significant impact on the life sciences field. Over the past decade, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been widely utilized as a rapid and reliable method for the identification of microorganisms. MALDI-TOF MS has come into widespread use despite its relatively low resolving power (full width at half maximum, FWHM: < 5,000) and its incompatibility with tandem MS analysis, features with which other high-resolution mass spectrometers are equipped. Microbial identification is achieved by searching databases containing mass spectra of peptides and proteins extracted from microorganisms of interest, using scoring algorithms to match analyzed spectra with reference spectra. In this paper, we give a brief overview of the diverse applications of rapid and robust MALDI-TOF MS-based techniques for microbial identification in a variety of fields, such as clinical diagnosis and environmental and food monitoring. We also describe the fundamental principles of MALDI-TOF MS. The general specifications of the two major MS-based microbial identification systems available in the global market (BioTyper® and VITEK® MS Plus) and the distribution of these instruments in Republic of Korea are also discussed. The current review provides an understanding of this emerging microbial identification and classification technology and will help bacteriologists and cell biologists take advantage of this powerful technique.

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

Antimicrobial Resistance, Virulence Genes and PFGE-profiling of Escherichia coli Isolates from South Korean Cattle Farms: Seung Won Shin , Jae-Won Byun , Myounghwan Jung , Min-Kyoung Shin , Han Sang Yoo; J. Microbiol. 2014;52(9):785-793. Published online July 30, 2014; DOI: https://doi.org/10.1007/s12275-014-4166-1

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13 Citations

Abstract: To estimate the prevalence of Escherichia coli with potential pathogenicity in cattle farm in South Korea, a total of 290 E. coli isolates were isolated from cattle farms over a period of 2 years in South Korea. These were examined for phenotypic and genotypic characteristics including antimicrobial susceptibility, serotype, and gene profiles of virulence and antimicrobial resistance. The most dominant virulence gene was f17 (26.2%), followed by stx2 (15.9%), ehxA (11.0%), stx1 (8.3%), eae (5.2%), and sta (4.1%). Some shiga-toxin producing E. coli isolates possessed eae (15.9%). All isolates except for one showed resistance to one or more antimicrobials, with 152 isolates exhibiting multidrug-resistance. The most prevalent resistance phenotype detected was streptomycin (63.1%), followed by tetracycline (54.5%), neomycin (40.3%), cephalothin (32.8%), amoxicillin (30.0%), ampicillin (29.7%), and sulphamethoxazole/trimethoprim (16.6%). The associated resistance determinants detected were strAstrB (39.0%), tet(E) (80.0%), tet(A) (27.6%), aac(3)-IV (33.1%), aphA1 (21.4%), blaTEM (23.8%), and sul2 (22.1%). When investigated by O serotyping and PFGE molecular subtyping, the high degree of diversity was exhibited in E. coli isolates. These results suggest that E. coli isolates from South Korean cattle farms are significantly diverse in terms of virulence and antimicrobial resistance. In conclusion, the gastroinstestinal flora of cattle could be a significant reservoir of diverse virulence and antimicrobial resistance determinants, which is potentially hazardous to public health.

Clonal Spread of Carbapenem Resistant Acinetobacter baumannii ST92 in a Chinese Hospital during a 6-Year Period: Lei Huang , Liying Sun , Yan Yan; J. Microbiol. 2013;51(1):113-117. Published online March 2, 2013; DOI: https://doi.org/10.1007/s12275-013-2341-4

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19 Citations

Abstract: The carbapenem resistance rate of Acinetobacter baumannii in our hospital has increased steadily since 2004. The molecular epidemiology of carbapenem resistant A. baumannii (CRAB) clinical isolates was characterized by multilocus sequence typing (MLST) and rep-PCR in parallel, with pandrug susceptible A. baumannii (PSAB) used as control. MLST was performed to determine the sequence types (STs), and eBURST algorithm was used to analyze their relatedness. Carbapenem resistance related genes (oxa-23, oxa-24, oxa-51, oxa-58, imp, vim, and adeB) were screened using Polymerase Chain Reaction (PCR) method. 23 STs were identified in the 65 included isolates, with ST92 being the predominant clone. PSAB clustered into more singletons than CRAB. The positivity of oxa-23 and adeB correlated with high level carbapenem resistance (MICIPM>32 mg/L, MICMEM>32 mg/L) of CRAB ST92 isolates in 2009, which was different from the resistance pattern (MICIPM≤4 mg/L, 8 mg/L ≤MICMEM≤16 mg/L) of CRAB ST92 isolates in 2004. These observations suggest that clonal spread of CRAB ST92 isolates longitudinally is the possible reason for carbapenem resistance rate increase and correlate with high level carbapenem resistance in our hospital.

Molecular Serotyping of Salmonella enterica by Complete rpoB Gene Sequencing: Won-Jin Seong , Hyuk-Joon Kwon , Tae-Eun Kim , Deog-Yong Lee , Mi-Sun Park , Jae-Hong Kim; J. Microbiol. 2012;50(6):962-969. Published online December 30, 2012; DOI: https://doi.org/10.1007/s12275-012-2547-x

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18 Citations

Abstract: Serotyping has been the gold standard for identifying Salmonella, but it requires large amounts of standard antisera. Multilocus sequence typing (MLST) has been applied to identify Salmonella serovars, but the recombination of 4–7 housekeeping genes and multiple analytic steps diminish its applicability. In the present study, we determined the complete sequences of the RNA polymerase beta subunit gene (rpoB) and 7 housekeeping genes (aroC, dnaN, hemD, hisD, purE, sucA, and thrA) for 76 strains of 33 Salmonella enterica serovars and conducted phylogenetic analyses together with the corresponding gene sequences of 24 reference strains registered in the GenBank database. Based on the phylogenetic analyses, 100 strains from 40 serovars and 91 strains from 37 serovars were classified into 60 rpoB (RST) and 49 multilocus sequence types (ST), respectively. The nucleotide similarities were 98.8–100% and 96.9–100% for the complete rpoB gene and the seven concatenated housekeeping genes, respectively. The strains of 35 and 30 serovars formed serovar-specific branches or clusters in the rpoB and housekeeping gene phylogenetic trees, respectively. Therefore, complete rpoB gene sequencing and phylogenetic analysis may be a useful method for identifying Salmonella serovars that is a simpler, more cost-effective, and less time-consuming alternative or complementary method to MLST and conventional serotyping.

Journal Articles

Re-identification of Aspergillus fumigatus sensu lato Based on a New Concept of Species Delimitation: Seung-Beom Hong , Dae-Ho Kim , In-Cheol Park , Young-Joon Choi , Hyeon-Dong Shin , Robert Samson; J. Microbiol. 2010;48(5):607-615. Published online November 3, 2010; DOI: https://doi.org/10.1007/s12275-010-0084-z

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16 Citations

Abstract: The species concept of Aspergillus fumigatus sensu stricto has recently been defined by polyphasic taxonomy. Based on the new concept of species delimitations, 146 worldwide strains of Aspergillus fumigatus sensu lato were re-identified. Of those 146 strains, 140 (95.8%) could be identified as A. fumigatus sensu stricto, 3 (2.1%) as A. lentulus, and the remaining 3 strains as A. viridinutans complex, Neosartorya udagawae, and N. cf. nishimurae. Of 98 clinical strains, only 1 from dolphin nostril was identified as A. lentulus and not A. fumigatus sensu stricto. Random amplification of polymorphic DNA-polymerase chain reaction (RAPD-PCR) with primers PELF and URP1F produced nearly the same band patterns among 136 strains of A. fumigatus sensu stricto while discriminated the species from its related species. We also discussed about identification of several atypical A. fumigatus strains from clinical environments.

Genotypic Characteristics of Haemophilus influenzae Isolates from Pediatric Pneumonia Patients in Chengdu City, Sichuan, China: Tian Guozhong , Zhang Li , Li Machao , Wang Xiaolei , Zheng Yuhong , Li Xiaojing , Huang Cheng , Li Xuechun , Xie Yongqiong , Xu Li , Ren Hongyu , Shao Zhujun; J. Microbiol. 2009;47(4):494-497. Published online September 9, 2009; DOI: https://doi.org/10.1007/s12275-009-0002-4

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7 Citations

Abstract: Two hundred and seventy-three Haemophilus influenzae strains isolated from pediatric pneumonia patients in China were studied. We used Multilocus Sequence Typing (MLST) to analyze genotypic characteristics. All strains were biotyped and serotyped. Relatedness and patterns of genes among isolates were determined by the analysis of MLST and eBURST. H. influenzae primarily causes acute pneumonia in children under 1 year old. Nontypeable H. influenzae was responsible for most cases of pediatric pneumonia. All 273 strains were classified into eight biotypes. They mostly belonged to the I, II, and III biotypes (17.6%, 43.6%, and 22.7%, respectively). 62 strains (22.7%) produced β-lactamase. We found 28 novel alleles. Fifty different STs were found by MLST, of which 39 were novel. These were ST477 through ST508 and ST521 through ST527. Group 17 and predicted founders 503 were new groups in this study. No STs correlated with strains from Korea, which is adjacent to China. The H. influenzae strains from China appeared to have heterogeneous ST types patterns which may be the reason no outbreaks or epidemics of H. influenzae infections have occurred in Chengdu city, Sichuan, China.

Phage Types and Pulsed-Field Gel Electrophoresis Patterns of Salmonella enterica serovar Enteritidis Isolated from Humans and Chickens: Sung Hun Kim , Shukho Kim , Sung Guen Chun , Mi-Sun Park , Jeong Hyun Park , Bok-Kwon Lee; J. Microbiol. 2008;46(2):209-213. Published online June 11, 2008; DOI: https://doi.org/10.1007/s12275-007-0197-1

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14 Citations

Abstract: We analyzed 66 Salmonella Enteritidis isolates in 2002. Thirty isolates were obtained from human patients with diarrhea, and 36 were obtained from chickens. A total of ten phage types (PT) were identified in the human and chicken isolates. PT1 and PT21 were the predominant PTs in both the human (20% and 13%) and chicken (17% and 47%) isolates. Twelve pulsotypes were generated by PFGE and divided into two major groups. Most of the PFGE types were categorized into cluster group 1. Eighteen chicken isolates in cluster group 1 showed high-level genetic association (>95%) with 22 other human isolates. Additionally, six chicken isolates from cluster group 2 showed fairly high-level genetic association (>95%) with the other seven human isolates. The highest levels of genetic association in humans and chickens were seen with A5-PT21 (11 isolates), A2-PT1 (7 isolates), and B1-PT4 (6 isolates). The Pulsed-Field Gel Electrophoresis (PFGE) and phage typing provided conclusive evidence that human Salmonella infections are attributable to the consumption of contaminated chicken.

Research Support, Non-U.S. Gov't

Genetic Characterization of the Escherichia coli O66 Antigen and Functional Identification of its wzy Gene: Jiansong Cheng , Bin Liu , David A. Bastin , Weiqing Han , Lei Wang , Lu Feng; J. Microbiol. 2007;45(1):69-74.; DOI: https://doi.org/2488 [pii]

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Abstract: Escherichia coli is a clonal species, and occurs as both commensal and pathogenic strains, which are normally classified on the basis of their O, H, and K antigens. The O-antigen (O-specific polysaccharide), which consists of a series of oligosaccharide (O-unit) repeats, contributes major antigenic variability to the cell surface. The O-antigen gene cluster of E. coli O66 was sequenced in this study. The genes putatively responsible for the biosynthesis of dTDP-6-deoxy-L-talose and GDP-mannose, as well as those responsible for the transfer of sugars and for O-unit processing were identified based on their homology. The function of the wzy gene was confirmed by the results of a mutation test. Genes specific for E. coli O66 were identified via PCR screening against representatives of 186 E. coli and Shigella O type strains. The comparison of intergenic sequences located between galF and the O-antigen gene cluster in a range of E. coli and Shigella showed that this region may perform an important function in the homologous recombination of the O-antigen gene clusters.

Journal Articles

The Molecular Characterization of Serogroup C Neisseria meningitidis Strains Circulating in Beijing: Tie-gang Zhang , Jing-guo He , Xiong He , Li-Juan Chen , Zhu-jun Shao , Mei-ping Sun; J. Microbiol. 2006;44(6):685-688.; DOI: https://doi.org/2455 [pii]

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Abstract: The aim of this study was to characterize the molecular features of serogroup C Neisseria meningitidis strains circulating in Beijing, China. Twenty out of 23 strains belonged to ST 4821. The causative serosubtype for meningococcal meningitis was P1.12-1,16-8. All of the strains expressed class 3 PorB protein. Among the five pulsed-field gel electrophoresis patterns observed, pattern III predominated.

Laboratory Confirmation of A Suspicious Meningococcal Meningitis Death Case: Tie-gang Zhang , Xiong He , Li-juan Chen , Jing-guo He , Ming Luo , Jie Yang , Zhu-jun Shao , Mei-ping Sun; J. Microbiol. 2006;44(4):457-460.; DOI: https://doi.org/2405 [pii]

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Abstract: A suspicious meningococcal meningitis death case was reported to the Beijing CDC. The blood specimen was analyzed via multi-PCR and MLST. 6 isolates from close contacts were analyzed via PFGE and MLST. According to the results of the above analyses, the cause of this case was identified as a serogroup A Neisseria meningitidis, which, in terms of sequence typing, belonged the ST7 group.

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