Structural and Functional Importance of Outer Membrane Proteins in Vibrio cholerae Flagellum

Wasimul Bari,이강무,윤상선 한국미생물학회 2012 The journal of microbiology Vol.50 No.4

Vibrio cholerae has a sheath-covered monotrichous flagellum that is known to contribute to virulence. Although the structural organization of the V. cholerae flagellum has been extensively studied, the involvement of outer membrane proteins as integral components in the flagellum still remains elusive. Here we show that flagella produced by V. cholerae O1 El Tor strain C6706 were two times thicker than those from two other Gram-negative bacteria. A C6706 mutant strain (SSY11) devoid of two outer membrane proteins (OMPs),OmpU and OmpT, produced thinner flagella. SSY11 showed significant defects in the flagella-mediated motility as compared to its parental strain. Moreover, increased shedding of the flagella-associated proteins was observed in the culture supernatant of SSY11. This finding was also supported by the observation that culture supernatants of the SSY11 strain induced the production of a significantly higher level of IL-8in human colon carcinoma HT29 and alveolar epithelial A549 cells than those of the wild-type C6706 strain. These results further suggest a definite role of these two OMPs in providing the structural integrity of the V. cholerae flagellum as part of the surrounding sheath.

Potential Swimming Motility Variation by AcrR in Escherichia coli

( Ye Jin Kim ),( So Young Im ),( Jae Ok Lee ),( Ok Bin Kim ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.10

AcrR, the toxic-compounds-response regulator, regulates motility in microorganisms, presumably to escape from toxic environments. In this study, the genome-wide target genes of AcrR were investigated in a ΔacrR mutant strain by microarray analysis. In the absence of AcrR, the transcription of most flagella/motility genes was highly increased. In addition, flagella formation was increased in this mutant strain. Motility assays revealed that AcrR modulates swimming motility, but not swarming.

A tdcA Mutation Reduces the Invasive Ability of Salmonella enterica Serovar Typhimurium

Minjeong Kim,임상용,Dongho Kim,최현일,유상렬 한국분자세포생물학회 2009 Molecules and cells Vol.28 No.4

We previously observed that the transcription of some flagellar genes decreased in Salmonella Typhimurium tdcA mutant, which is a gene encoding the transcriptional activator of the tdc operon. Since flagella-mediated bacte-rial motility accelerates the invasion of Salmonella, we have examined the effect of tdcA mutation on the invasive ability as well as the flagellar biosynthesis in S. Typhi-murium. A tdcA mutation caused defects in motility and formation of flagellin protein, FliC in S. Typhimurium. Inva-sion assays in the presence of a centrifugal force con-firmed that the defect of flagellum synthesis decreases the ability of Salmonella to invade into cultured epithelial cells. In addition, we also found that the expression of Salmo-nella pathogenicity island 1 (SPI1) genes required for Sal-monella invasion was down-regulated in the tdcA mutant because of the decreased expression of fliZ, a positive regulator of SPI1 transcriptional activator, hilA. Finally, the virulence of a S. Typhimurium tdcA mutant was attenuated compared to a wild type when administered orally. This study implies the role of tdcA in the invasion process of S. Typhimurium.

Elucidation of the functional role of flagella in virulence and ecological traits of Pseudomonas cichorii using flagella absence (ΔfliJ) and deficiency (ΔfliI) mutants

Hung, N.B.,Ramkumar, G.,Bhattacharyya, D.,Lee, Y.H. Elsevier 2016 Research in microbiology Vol.167 No.4

Understanding the infection mechanisms of pathogens will lead to better management of the associated diseases. The flagella of these pathogens play significant roles not only in bacterial motility, but also in virulence. In the present study, two genes involved in flagella construction, fliJ and fliI of Pseudomonas cichorii, were analyzed. The results revealed that these genes are vital for flagella formation and play significant roles not only in motility, but also in virulence. When we inoculated host plants with fliI- and fliJ-defective mutants (ΔfliJ and ΔfliI) through the dipping method, the degree of disease severity caused by both mutants was significantly reduced compared to those of the wild-type. However, the virulence of ΔfliI was stronger than that of ΔfliJ. Electron microscope observation, and swarming and leaf attachment assays indicated a reduced number of flagella in ΔfliI, but not complete absence, because of the presence of another copy of fliI. Furthermore, a vacuum infiltration assay revealed that flagella are indispensable in the pre- and post-penetration stages for complete virulence. Overall, we created semi-defective (ΔfliI) and completely defective (ΔfliJ) mutants and elucidated the fact that flagella play significant roles in virulence of the pathogen at different stages of the infection process.

Role of Dual Flagella in the Pathogenesis of Vibrio parahaemolyticus

이화규,정병곤,박권삼 한국수산과학회 2011 Fisheries and Aquatic Sciences Vol.14 No.2

Vibrio parahaemolyticus possesses two flagella systems: polar and lateral flagella for swimming in liquid and swarming on solid surfaces or in viscous environments. To elucidate the pathogenic role of these dual flagella systems, we constructed single- and double-deletion mutants of the lafA and flhAB flagellum genes and investigated their biofilm formation, cell adhesion, and colonization of the small intestine of suckling mice. The double-mutant strain was more impaired in biofilm formation than either of the single-mutant strains. In addition, the lafA, flhAB, and double-mutant strains showed 40%, 45%, and 60%, respectively, lower adherence to HeLa cells than the wild-type strain. Moreover, the lafA, flhAB, and double-mutant strains exhibited 49%, 5.6 and 6.7 times, respectively, lower colonization in a competition assay than the wild-type strain. These findings indicated that polar flagella were more important than lateral flagella for the pathogenesis of V. parahaemolyticus.

Role of Dual Flagella in the Pathogenesis of Vibrio parahaemolyticus

Lee, Hwa-Gyu,Jeong, Byung-Gon,Park, Kwon-Sam The Korean Society of Fisheries and Aquatic Scienc 2011 Fisheries and Aquatic Sciences Vol.14 No.2

Vibrio parahaemolyticus possesses two flagella systems: polar and lateral flagella for swimming in liquid and swarming on solid surfaces or in viscous environments. To elucidate the pathogenic role of these dual flagella systems, we constructed single- and double-deletion mutants of the lafA and flhAB flagellum genes and investigated their biofilm formation, cell adhesion, and colonization of the small intestine of suckling mice. The double-mutant strain was more impaired in biofilm formation than either of the single-mutant strains. In addition, the lafA, flhAB, and double-mutant strains showed 40%, 45%, and 60%, respectively, lower adherence to HeLa cells than the wild-type strain. Moreover, the lafA, flhAB, and double-mutant strains exhibited 49%, 5.6 and 6.7 times, respectively, lower colonization in a competition assay than the wild-type strain. These findings indicated that polar flagella were more important than lateral flagella for the pathogenesis of V. parahaemolyticus.

Development of flagella bio-templated nanomaterials for electronics

Jo Wonjin,Cheang U Kei,Kim Min Jun 나노기술연구협의회 2014 Nano Convergence Vol.1 No.10

Bacterial flagella with their unique structural properties have proven to be promising bio-templates and can be exploited for the creation of nanomaterial with very high aspect ratio and surface area. Their chemically modifiable surfaces allow the flagella be modified to possess electrical/electronic properties. Their extraordinary physical properties along with the many possibilities for manipulation make them ideal systems to study for the purpose of developing nanoelectronics. First, this article reviews the characteristics of bacterial flagella and their utilization as biologically inspired templates. Next, the use of bio-templates for electronic systems such as dye-sensitized solar cell and lithium ion battery is discussed. Finally, we show the future directions for the use of flagella biotemplatednanomaterials for applications in electrical engineering fields.

살모넬라 편모 항원에 대한 난황항체(IgY)의 생산 및 특성

신순오,김도균,양시용,안태영,김정우 한국가금학회 2003 韓國家禽學會誌 Vol.30 No.3

1. S. choleraesuis, S. typhimurium, S. dublin에서 순수 분리한 flagella protein의 분자량은 각각 53.4 kDa, 51 kDa, 54.6 kDa으로 나타났다. 2. 산란계의 혈청 중 항체역가 수준은 면역 후 2주경 부터 급격히 증가하기 시작하였고 난황 중 항체역가의 수준은4 주경 부터 급격히 증가하기 시작하였다. 6주와 8주경 이 후 부터는 난황항체역가가 혈청 항체역가보다 높은 수준을 유지하거나 계속 증가하였다. 3. Salmonella flagella protein을 면역원으로 산란계에 면역하여 생산된 난황항체는 150,000배 희석 시 각각의 Salmonella 균주에서 특이적으로 각각의 항원에 반응하였다. 4. 난황 1 ml당 IgY의 함량은 약 31 mg∼33 mg이었으며, IgY의 함량은 단백질 함량의 약27%를 차지하는 것으로 나타났다. 5. 실험실조건하에서 난황항체의 항원결합능력을 조사한 결과 동결건조한 WSF을 2∼4 mg/ml첨가 시 균체의 농도가 $10^{9}$ CFU/ml에서 $10^{5}$∼$10^{6}$ CFU/ml로 급격하게 감소하였다.다. Egg yolk antibodies(IgY) from laying hens immunized with antigens from Salmonella choleraesuis, Salmonella typhimurium and Salmonella dublin were produced. The Antigenic proteins isolated from those flagella of Salmonella sp., determined by SDS-PAGE, were pure and had a molecular mass of approximately 53.4, 51 and 54.6 kDa, respectively. The IgY titers were found at two weeks after first immunization and increased gradually to maximum of 330,000 300,000 and 440,000 respectively. According to the results of specificity test by ELISA, the IgY raised against Salmonella sp. were found highly specific activity levels. Concentration of Salmonella sp. incubated with anti-Salmonella sp. IgY were drastically reduced to the levels of 2.8∼4.0 log CFU/ml. The contents of IgY in an egg yolk was approximately 31∼33 mg/ml.

Detecting Salmonella Type II flagella production by transmission electron microscopy and immunocytochemistry

Yoontak Han,Eun-Jin Lee 한국미생물학회 2020 The journal of microbiology Vol.58 No.4

The bacterial flagellum is an appendage structure that provides a means for motility to promote survival in fluctuating environments. For the intracellular pathogen Salmonella enterica serovar Typhimurium to survive within macrophages, flagellar gene expression must be tightly regulated, and thus, is controlled at multiple levels, including DNA recombination, transcription, post-transcription, protein synthesis, and assembly within host cells. To understand the contribution of flagella to Salmonella pathogenesis within the host, it is critical to detect flagella production within macrophages via microscopy. In this paper, we describe two methods for detecting bacterial flagella by microscopy both in vitro and in vivo infection models.

Review : Role of flgA for Flagellar Biosynthesis and Biofilm Formation of Campylobacter jejuni NCTC11168

( Joosung Kim ),( Changwon Park ),( Yunji Kim ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.11

The complex roles of flagella in the pathogenesis of Campylobacter jejuni, a major cause of worldwide foodborne diarrheal disease, are important. Compared with the wild-type, an insertional mutation of the flgA gene (cj0769c) demonstrated significant decrease in the biofilm formation of C. jejuni NCTC11168 on major food contact surfaces, such as polystyrene, stainless steel, and borosilicate glass. The flgA mutant was completely devoid of flagella and non-motile whereas the wild-type displayed the full-length flagella and motility. In addition, the biofilm formation of the wild-type was inversely dependent on the viscosity of the media. These results support that flagellar-mediated motility plays a significant role in the biofilm formation of C. jejuni NCTC11168. Moreover, our adhesion assay suggests that it plays an important role during biofilm maturation after initial attachment. Furthermore, C. jejuni NCTC11168 wild-type formed biofilm with a net-like structure of extracellular fiber-like material, but such a structure was significantly reduced in the biofilm of the flgA mutant. It supports that the extracellular fiber-like material may play a significant role in the biofilm formation of C. jejuni. This study demonstrated that flgA is essential for flagellar biosynthesis and motility, and plays a significant role in the biofilm formation of C. jejuni NCTC11168.