Cells of the genus Azospirillum possess a single polar flagellum when grown in broth; when grown on solid media they also possess numerous lateral flagella of shorter wavelength (0.7 µm vs. 1.2 µm) and thinner diameter (13.5 nm vs. 18 nm). The antigenic and functional differences between these two types of flagella were studied for A. brasilense ATCC 29145 (type strain). An indirect immunoperoxidase stain was used in conjunction with electron microscopy to demonstrate that an antigenic difference that exists between these two types of flagella in this strain. No evidence could be obtained that the polar flagellum was ensheathed as it is in members of the genus Vibrio. A. brasilense was found to swarm on nutrient broth medium solidified with 0.75% agar ("swarm medium" or SM), and also on medium solidified with carrageenan. Swarming also occurred on a dialysis membrane overlying SM, indicating that the nature of the solid surface may not be important. The effects of various physical and chemical factors on swarming were determined. A temperature of 30°C rather than the optimal growth temperature of 37°C was stimulatory to swarming. Certain chemical agents, p-nitrophenylglycerol, EDTA, sodium deoxycholate, sodium taurocholate, and Na₂SO₄, at appropriate concentrations could inhibit swarming without preventing growth. Based on the use of mutants lacking either the polar flagellum or the lateral flagella, the lateral flagella were found to be responsible for swarming, whereas the polar flagellum was responsible for free-swimming motility. / M.S.

A unique undosciribed gramnegative rod is extensively characterized in this study. The cells of this unusual water isolate measure 1.2 X 6.5 microns, The most distinguishing characteristic of the bacterium is a polar tuft of 35-40 flagella that aggregate to function as a single organelle which is visible under phase contrast. Aging cells deposit poly- -hydroxybutyric acid granules which are bound by an inclusion membrane made up of four distinct layers. It also possesses an unusual exterior membrane outside the cell wall which contains large fibrils of protein running at a slight angle to the longitudinal axis of the cell. The guanosine-cytosine ratio was found to be 62.2$. The organism's taxonomic position was further investigated by immunological, morphological, and biochemical methods. It was found to be most closely akin to members of the genus Pseudo onas, although somewhat divergent from other species classified in this genus. After careful evaluation of the findings obtained during this study, the new bacterium was subsequently named Pseudomonas multiflagella.

Typewritten copy Includes bibliographical references (leaves 141-144) Pt. 1. Historical review -- pt. 2. Techniques used in electron microscopy -- pt. 3. Experiments on cilia from Hydrdella australis -- pt. 4. Electron microscope experiments on cilia from the rat trachea -- pt. 5. Electron microscope experiments on cilia from paramecium -- pt. 6. Electron microscope experiments on the trichocysts of paramecium -- pt. 7. Discussion An account of experimental investigations carried out from January 1952 to September 1954.

Typewritten copy / Includes bibliographical references (leaves 141-144) / [5], 144 leaves : ill. ; 27 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / An account of experimental investigations carried out from January 1952 to September 1954. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1956

In 1971 Strength and Krieg reported the isolation of a floe-forming gram-negative freshwater rod which exhibited large bipolar flagellar fascicles. Despite the intense activity of the fascicles, the organism had appeared unable to swim. However, free-swimming has now been demonstrated within the highly viscous floes formed by the organisms in viscous solutions of gelatin, DNA and methyl cellulose. With each of these viscous agents there existed an optimum concentration for motility. Higher or lower concentrations led to a decrease in motility. In methyl cellulose, strain XI exhibited optimum motility at a viscosity of 200 cp, while strains X and XI were optimal at 10 cp. Nitrogenase activity was demonstrated by the use of the semisolid medium of Döbereiner and Day. No nitrogenase activity occurred when liquid medium was used, and the organisms were obligately microaerophilic in nitrogen-free medium. When (NH₄)₂SO₄ was supplied, no nitrogenase activity occurred and the organism grew best aerobically. The characteristics of strains X, XI and XII indicated that the organisms should be assigned to genus Aquaspirillum. This decision was based on the following considerations: large bipolar fascicles of flagella, a strictly respiratory metabolism, inability to attack carbohydrates, presence of intracellular poly-β-hydroxybutyrate granules, positive reactions for catalase, oxidase and phosphatase, lack of tolerance to 3% NaCl, occurrence of a "polar membrane" in thin sections, and a DNA base composition of 62 to 65% G+C. The strains have been placed in the species Aquaspirillum fasciculus sp. nov. / M.S.

Thesis (Ph. D.)--West Virginia University, 2005 / Title from document title page. Document formatted into pages; contains ix, 210 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.

Orientador: Domingos da Silva Leite / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-17T10:33:43Z (GMT). No. of bitstreams: 1 Moura_Claudiade_D.pdf: 2791356 bytes, checksum: 7830cb1ece9ec9ac3c34c2794b264c93 (MD5) Previous issue date: 2010 / Resumo: Escherichia coli é um membro comensal da microbiota de animais, porém podem causar doenças desde diarréias até sepses. A caracterização dos seus antígenos de superfície O (somático) e H (flagelar) auxilia na determinação de linhagens patogênicas dentro da espécie. Contudo, algumas bactérias não expressam flagelo in vitro, demonstrado que a amplificação do gene fliC, a análise dos fragmentos de polimorfismo (PCR-RFLP) e sequenciamento podem ser utilizadas para identificação dos antígenos H, em substituição à sorologia convencional. Até meados de 1980, pensava-se que, diferentemente da Salmonella, E. coli possui um único gene para expressão de flagelina (fliC), mas algumas amostras podem conter genes para expressão de flagelina flkA, fllA, flmA, flnA e fljA (repressor de fliC). Em nosso trabalho, analisamos 31 amostras de E. coli isolados de animais e alimentos que apresentavam o fenótipo HNT em ensaios de sorologia. Utilizamos PCR-RFLP e sequenciamento para descrever novos genes para flagelina, da qual foram obtidos antissoros. Identificamos por PCR e sequenciamento os genes responsáveis pela variação de fase fljA, flkA e flmA, realizamos experimentos de motilidade para determinar a variação de fase flagelar e detectar a expressão dos genes através de RT-PCR. Dezessete amostras tiveram seus antígenos H caracterizados, sendo nove caracterizadas por PCR-RFLP: H2 (duas amostras) H16 (duas amostras), H34 (três amostras), H33 (uma amostra) e H38 (uma amostra). Na análise de sequenciamento identificamos duas amostras portadoras do gene fliCh25, duas amostras fliCh7 e uma amostra apresentando fliCh32. Três novos genes para flagelina foram descritos: fliCh2', fliC4c, fliC40c. Identificamos o gene fljA em duas amostras HNT (3C e 4C) e na amostra padrão H35. O gene das amostras HNT apresentaram homologia ao fljA de Salmonella enterica, cuja variação de fase é bem estabelecida. As amostras padrão H11, H35, H40 e H47, bem como as amostras HNT 3C e 4C foram positivas para o gene flmA. As amostras padrão H3 e H53 são portadoras do gene flkA, contudo apenas a amostra H53 apresentou fljA. A amostra H54 é portadora de fljA e flmA. Nenhuma amostra H padrão mostrou variação de fase, diferentemente da literatura, sugerindo a perda da capacidade de variar a fase flagelar. A amostra 4C mostrou variação de fase positiva quando induzida em meios de cultura contendo antissoros anti-H48, anti-H54 e anti-H4C. Do mesmo modo, a detecção dos RNAm em diferentes condições de cultura confirmou a variação de fase. Como resultado um esquema de identificação para detecção de grupos de antígenos H e identificação de fliC foi testado. A técnica de fliC-RFLP provou ser eficiente e rápida, auxiliando a sorologia clássica para detecção de antígenos H de E. coli. Um modelo geral de variação de fase da amostra 4C é expresso por fliCoff + flmAon ? fliCon + flmAoff. Além disso, nós verificamos que a amostra 4C apresenta um gene novo para expressão de flagelina. Este trabalho é pioneiro em relação à variação de fase flagelar, demonstrando uma nova associação entre os antígenos H48 e H54 / Abstract: Escherichia coli are a species of microflora, and characterization of the cell surface lipopolysaccharide O antigen and the flagellar H antigen allow the grouping of pathogenic clones within this species. Moreover, some bacteria in vitro do not obtain to express its flagella, demonstrated that PCR-restriction fragment length polymorphism (PCR-RFLP) and sequencing analysis has been used for the identification of these antigens, in substitution of traditional serology. Moreover, until middle of years 80, are believed, differently of the Salmonella, E. coli possesss an only gene for flagelin expression (fliC), but some s/strains can contain genes for flagellin expression flkA, fllA, flmA, flnA and fljA (repressor of fliC). In this work, we analyzed 31 strains of E. coli isolated from animals and foods that presented HNT phenotype in serology assays. We use PCR-RFLP and sequencing to describe new genes for flagellin, of which antiserum were obtained. We identify for PCR and sequencing the genes for phase variation fljA, flkA and flmA, we carry through motility experiments to determine the flagellar phase variation and to detect the expression of the genes (RNAm) through RT-PCR. Seventeen strains had had its H antigen characterized and nine of then were characterized for PCR-RFLP: H2 (two strains) H16 (two strains), H34 (three strains), H33 (one strain) and H38 (one strain). Through sequencing analysis we identify to two carrying strains of the gene fliCh25, two strains fliCh7 and one strain presenting fliCh32. Three new genes for flagellin had been described: fliCh2', fliC4c, fliC40c. Using PCR and sequencing, we identify fljA gene in two strains HNT (3C and 4C) and in the H35 control strain. The HNT genes showed homology to fljA of Salmonella enterica, whose variation of phase well is established. The control strains H11, H35, H40 and H47, as well as HNT 3C and 4C strains were positive for flmA gene. The control strains H3 and H53 are carrying of flkA gene, however only the H53 strain presented fljA. The H54 control strain is carrying of fljA and flmA. No H control strain showed phase variation, differently of literature, suggesting the loss of the capacity to flagellar phase variation. The 4C strain showed positive phase variation when cultured with antiserum anti-H48, anti-H54 and anti-H4C. In a similar way, the detention of RNAm in different conditions of culture confirmed the phase variation. As a result, an identification scheme was tested to deduce H antigen groups and new genes of fliC. The fliCRFLP technique proved to be faster than classic serotyping for the deduction of the E. coli H antigen, characterizing the antigens with few days and indicating new putative genes. Thus, a general model for flagellar phase variation in 4C strain can be expressed as fliCoff + flmAon ? fliCon + flmAoff. In addition, we found that strains 3C and 4C express unidentified flagellin antigens. This is the first report of flagellar phase variation in wild E. coli strains. We have also provided evidence that strain 4C, identified here for the first time, expresses three flagellar antigens, H48, H54 and a previously unidentified flagellin / Doutorado / Microbiologia / Doutor em Genetica e Biologia Molecular

Orientador: Domingos da Silva Leite / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-14T15:47:58Z (GMT). No. of bitstreams: 1 Tiba_MoniqueRibeiro_D.pdf: 3934673 bytes, checksum: 211302f7129afd8376ba9096064a21c4 (MD5) Previous issue date: 2009 / Resumo: Escherichia coli tem sido isolada, com certa freqüência, apresentando antígenos flagelares (H) que não são reconhecidos por nenhum dos anti-soros disponibilizado pelo mais importante centro de referência de E. coli, The International Escherichia and Klebsiella Centre (WHO) do Statens Serum Institut, Copenhague, Dinamarca. Atualmente são reconhecidos 53 antígenos "H" e, nos últimos 29 anos, nenhuma modificação ocorreu na lista dos antígenos flagelares associados à Escherichia coli. Isto posto, os objetivos deste trabalho foram identificar os antígenos flagelares das cepas de E. coli que expressam H não tipável (HNT) e que apresentam fatores de virulência associados à diferentes enteropatias. Esta identificação foi realizada inicialmente, pela reação em cadeia da polimerase (PCR) do gene fliC, responsável pela proteína flagelina, das 53 amostras padrões para os antígenos H e das 20 amostras HNT (H não-tipável). Em seguida, os amplicons foram digeridos por enzimas de restrição e daquelas amostras que apresentaram perfis de restrições distintos daqueles observados para as amostras padrões de antígeno H, foram produzidos soros em coelhos. Foram realizados testes de titulação frente aos 53 antígenos padrões, frente ao antígeno homólogo e frente aos antígenos das amostras HNT. As seqüência gênicas das amostras HNT, obtidas na reação de sequenciamento, foram comparadas aos diferentes genes de fliC armazenados no banco de dados do "National Center for Biotecnology Information" (NCBI) através do sistema BLAST, e o programa ClustalW foi utilizado para alinhamento das seqüências. Os resultados demonstraram que estas amostras apresentaram similaridade com antígenos padrões, entretanto, elas não possuem a mesma seqüência nucleotídica e também não reagiram fenotipicamente com o anti-soro esperado. Os dados obtidos permitem concluir que no conjunto de amostras estudado, treze amostras apresentaram antígeno flagelar diferente daqueles já descritos na literatura, quando utilizado as técnicas de PCR e/ou sorologia. / Abstract: Escherichia coli has been isolated frequently, showing flagellar antigens that are not recognized by any of the antisera, provided by the most important reference center of E. coli, The International Escherichia and Klebsiella Centre (WHO) of the Statens Serum Institute, Copenhagen, Denmark. Are currently recognized 53 H antigens and in the last 29 years, no change occurred in the list of flagellar antigens associated with Escherichia coli. The objectives of this study were to identify the flagellar antigens of E. coli that do not express non-typeable H antigens and presenting the virulence factors associated with different diseases. This identification was performed initially by gene amplification of the fliC, (flagellin protein) by the polymerase chain reaction (PCR) in all 53 standards E. coli strains for the H antigens and 20 non-typeable H-antigens E. coli strains, being then, the amplicons were digested by restriction enzymes. Anti-sera were produced in rabbits, those strains that showed different restriction profiles of these patterns observed for the nontypeable H antigens E. coli strains. Agglutination testes were carried out against the 53 antigens standards, against the homologous antigen and H antigens of the non-typeable strains. DNA sequences were compared to different fliC genes stored in the database of the National Center for Biotecnology Information (NCBI) through the BLAST, and ClustalW program was used to align the sequences. The results showed that although these strains have homology with a standard H-antigen, they do not have the same nucleotide sequence and did not phenotypically reacted with the antiserum expected. The data obtained showed that thirteen strains had a different H antigen those already described in the literature when used the techniques of PCR-RFLP and/or serology. / Doutorado / Microbiologia / Doutor em Genetica e Biologia Molecular

A HP1076 null mutant has been constructed to provide a better understanding of the biological significance of HP1076 in H. pylori . The DeltaHP1076 mutant displays impaired motility and resistance to the antibiotic drug metronidazole. Using a proteomic study, an overall of 40 differentially expressing proteins involved in metabolism and pH homeostasis for bacterial survival, adhesion for colonization, virulence factor to gastric epithelial cells and antigenic proteins have been identified. The virulence factor, Cag pathogenicity island protein (Cag 26) and urease UreA and UreB are confirmed to have enhanced and reduced expression in null mutants. These findings may provide new insight into the infection of H. pylori. / FliS is an export chaperone that binds to flagellin molecules in cytosol in order to prevent pre-mature polymerization. Disruption of FliS would result in formation of shorter flagella and impaired adhesion ability to epithelial cells. Previous yeast two-hybrid study has identified various FliS associated proteins in H. pylori, but with no known implications. Here, we have demonstrated the interaction of FliS and a hypothetical protein HP1076 by biochemical and biophysical methods. Moreover, HP1076 possesses anti-aggregation ability on insoluble FliS-mutants and chaperone activity. Thus, HP1076 is proposed to be a co-chaperone that promotes the folding and chaperone activity of FliS. FliS is demonstrated to have a broad range of substrate specificity that binds to flagellin and flagellar related proteins which may play a key role in flagellar export system different from other flagellated bacteria. / Helicobacter pylori is a pathogenic bacterium and adheres to the gastric mucosal cells. Chronic infection would lead to gastritis or peptic ulceration and is one of the leading causes of gastric cancer. Formation of functional flagella is essential for infection, that it aids in motility of bacteria and colonization on gastric epithelial cells. The process is complex and involves more than 50 proteins in assembly of structural proteins, regulatory proteins, an export apparatus, a motor and a sensory system. Cytosolic chaperones are required to bind to exported proteins in order to facilitate the export or prevent the aggregation of proteins in cytosol. Divergence is found in flagellar system H. pylori that may account for survival inside gastric environment. / The crystal structures of FliS, HP1076 fragment and FliS/HP1076 complex are determined at 2.7A, 1.8A and 2.7A resolution respectively to provide better understanding of their molecular interactions. FliS consists of four helices and HP1076 consists of helical rich bundle structure with three helices and three beta strands that share similar fold to that of a flagellin homologue, hook-associated protein and FliS, suggesting HP1076 is involved in flagellar system. The FliS/HP1076 complex reveals an extensive electrostatic and hydrophobic binding interface which is distinct from the flagellin binding pocket on FliS. HP1076 stabilizes two alpha helices of FliS and therefore the overall bundle structure. Our findings provide new insights into the flagellar export chaperones and other secretion chaperones in Type III secretion system. / Lam, Wai Ling. / Adviser: An Wing-Ngor. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 223-243). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.