Identification of a novel anti-σE factor in Neisseria meningitidis

<p>Abstract</p> <p>Background</p> <p>Fine tuning expression of genes is a prerequisite for the strictly human pathogen <it>Neisseria meningitidis </it>to survive hostile growth conditions and establish disease. Many bacterial species respond to stress by using alternative σ factors which, in complex with RNA polymerase holoenzyme, recognize specific promoter determinants. σ^E, encoded by <it>rpoE </it>(NMB2144) in meningococci, is known to be essential in mounting responses to environmental challenges in many pathogens. Here we identified genes belonging to the σ^Eregulon of meningococci.</p> <p>Results</p> <p>We show that meningococcal σ^Eis part of the polycistronic operon NMB2140-NMB2145 and autoregulated. In addition we demonstrate that σ^Econtrols expression of methionine sulfoxide reductase (MsrA/MsrB). Moreover, we provide evidence that the activity of σ^Eis under control of NMB2145, directly downstream of <it>rpoE</it>. The protein encoded by NMB2145 is structurally related to anti-sigma domain (ASD) proteins and characterized by a zinc containing anti-σ factor (ZAS) motif, a hall mark of a specific class of Zn^2+-binding ASD proteins acting as anti-σ factors. We demonstrate that Cys residues in ZAS, as well as the Cys residue on position 4, are essential for anti-σ^Eactivity of NMB2145, as found for a minority of members of the ZAS family that are predicted to act in the cytoplasm and responding to oxidative stimuli. However, exposure of cells to oxidative stimuli did not result in altered expression of σ^E.</p> <p>Conclusions</p> <p>Together, our results demonstrate that meningococci express a functional transcriptionally autoregulated σ^Efactor, the activity of which is controlled by a novel meningococcal anti-σ factor belonging to the ZAS family.</p

Genotyping of Chlamydophila psittaci in Human Samples

Chlamydophila (formerly Chlamydia) psittaci genotypes A, B, C, and a new genotype most similar to the 6BC type strain were found in 10 humans with psittacosis by outer membrane protein A gene sequencing. Genotypes B (n = 3) and C (n = 1) are endemic in nonpsittacine European birds. These birds may represent an important part of the zoonotic reservoir

Multi locus sequence typing of Chlamydiales: clonal groupings within the obligate intracellular bacteria Chlamydia trachomatis

<p>Abstract</p> <p>Background</p> <p>The obligate intracellular growing bacterium <it>Chlamydia trachomatis </it>causes diseases like trachoma, urogenital infection and lymphogranuloma venereum with severe morbidity. Several serovars and genotypes have been identified, but these could not be linked to clinical disease or outcome. The related <it>Chlamydophila pneumoniae</it>, of which no subtypes are recognized, causes respiratory infections worldwide. We developed a multi locus sequence typing (MLST) scheme to understand the population genetic structure and diversity of these species and to evaluate the association between genotype and disease.</p> <p>Results</p> <p>A collection of 26 strains of <it>C. trachomatis </it>of different serovars and clinical presentation and 18 strains of <it>C. pneumoniae </it>were included in the study. For comparison, sequences of <it>C. abortus, C. psittaci</it>, <it>C. caviae</it>, <it>C. felis</it>, <it>C. pecorum </it>(<it>Chlamydophila</it>), <it>C. muridarum </it>(<it>Chlamydia</it>) and of <it>Candidatus protochlamydia </it>and <it>Simkania negevensis </it>were also included. Sequences of fragments (400 – 500 base pairs) from seven housekeeping genes (<it>enoA</it>, <it>fumC</it>, <it>gatA</it>, <it>gidA</it>, <it>hemN</it>, <it>hlfX</it>, <it>oppA</it>) were analysed. Analysis of allelic profiles by eBurst revealed three non-overlapping clonal complexes among the <it>C. trachomatis </it>strains, while the <it>C. pneumoniae </it>strains formed a single group. An UPGMA tree produced from the allelic profiles resulted in three groups of sequence types. The LGV strains grouped in a single cluster, while the urogenital strains were distributed over two separated groups, one consisted solely of strains with frequent occurring serovars (E, D and F). The distribution of the different serovars over the three groups was not consistent, suggesting exchange of serovar encoding <it>ompA </it>sequences. In one instance, exchange of <it>fumC </it>sequences between strains of different groups was observed. Cluster analyses of concatenated sequences of the Chlamydophila and Chlamydia species together with those of <it>Candidatus Protochlamydia amoebophila </it>and <it>Simkania negevensis </it>resulted in a tree identical to that obtained with 23S RNA gene sequences.</p> <p>Conclusion</p> <p>These data show that <it>C. trachomatis </it>and <it>C. pneumoniae </it>are highly uniform. The difference in genetic diversity between <it>C. trachomatis </it>and <it>C. pneumoniae </it>is in concordance with a later assimilation to the human host of the latter. Our data supports the taxonomy of the order of <it>Chlamydiales</it>.</p

Molecular characterization and identification of proteins regulated by Hfq in Neisseria meningitidis

Hfq is a highly conserved pleiotropically acting prokaryotic RNA-binding protein involved in the post-transcriptional regulation of many stress-responsive genes by small RNAs. In this study, we show that Hfq of the strictly human pathogen Neisseria meningitidis is involved in the regulation of expression of components involved in general metabolic pathways, iron metabolism and virulence. A meningococcal hfq deletion strain (H44/76Δhfq) is impaired in growth in nutrient-rich media and does not grow at all in nutrient-limiting medium. The growth defect was complemented by expression of hfq in trans. Using proteomics, the expression of 28 proteins was found to be significantly affected upon deletion of hfq. Of these, 20 proteins are involved in general metabolism, among them seven iron-responsive genes. Two proteins (PilE, TspA) are involved in adherence to human cells, a step crucial for the onset of disease. One of the differentially expressed proteins, GdhA, was identified as an essential virulence factor for establishment of sepsis in an animal model, studied earlier. These results show that in N. meningitidis Hfq is involved in the regulation of a variety of components contributing to the survival and establishment of meningococcal disease

Full genome sequences of all nine Chlamydia psittaci genotype reference strains

Chlamydia psittaci primarily infects birds, but zoonotic transmission occurs in people in close contact with infected birds. The clinical outcome ranges from inapparent disease to pneumonia. Here we report the genome sequences of all 9 Chlamydia psittaci genotype reference strains. © 2012, American Society for Microbiology

Multi Locus Sequence Typing of Chlamydia Reveals an Association between Chlamydia psittaci Genotypes and Host Species

Chlamydia comprises a group of obligate intracellular bacterial parasites responsible for a variety of diseases in humans and animals, including several zoonoses. Chlamydia trachomatis causes diseases such as trachoma, urogenital infection and lymphogranuloma venereum with severe morbidity. Chlamydia pneumoniae is a common cause of community-acquired respiratory tract infections. Chlamydia psittaci, causing zoonotic pneumonia in humans, is usually hosted by birds, while Chlamydia abortus, causing abortion and fetal death in mammals, including humans, is mainly hosted by goats and sheep. We used multi-locus sequence typing to asses the population structure of Chlamydia. In total, 132 Chlamydia isolates were analyzed, including 60 C. trachomatis, 18 C. pneumoniae, 16 C. abortus, 34 C. psittaci and one of each of C. pecorum, C. caviae, C. muridarum and C. felis. Cluster analyses utilizing the Neighbour-Joining algorithm with the maximum composite likelihood model of concatenated sequences of 7 housekeeping fragments showed that C. psittaci 84/2334 isolated from a parrot grouped together with the C. abortus isolates from goats and sheep. Cluster analyses of the individual alleles showed that in all instances C. psittaci 84/2334 formed one group with C. abortus. Moving 84/2334 from the C. psittaci group to the C. abortus group resulted in a significant increase in the number of fixed differences and elimination of the number of shared mutations between C. psittaci and C. abortus. C. psittaci M56 from a muskrat branched separately from the main group of C. psittaci isolates. C. psittaci genotypes appeared to be associated with host species. The phylogentic tree of C. psittaci did not follow that of its host bird species, suggesting host species jumps. In conclusion, we report for the first time an association between C. psittaci genotypes with host species

Viininmaistelun alkeet -tapahtuma Maria P:ssä

Tiivistelmä Tekijät: Paananen Riina ja Korkiakoski Merika Työn nimi: Viininmaistelun alkeet -tapahtuma Maria P:ssä Tutkintonimike: Restonomi (AMK), matkailun koulutus Asiasanat: tapahtuma, viini, viininmaistelu, Chile Opinnäytetyön tarkoituksena oli suunnitella ja järjestää Viininmaistelun alkeet -tapahtuma. Tapahtuman toimeksiantajana toimi kajaanilainen yritys Viinibaari Maria P. Tapahtuma haluttiin toteuttaa baarin imagoon sopivaksi. Opinnäytetyön tavoitteena oli saada Viini-baarille lisää asiakkaita tutustuttamalla kokemattomia viininmaistajia viineihin. Työ oli toiminnallinen opinnäytetyö, jonka tuotoksena oli Viininmaistelun alkeet -tapahtuma. Opinnäytetyöhön kerättiin teoriapohjaa viininmaistelusta sekä viinin ja ruoan yhdistämisestä, Chilestä viinimaana ja tapahtuman järjestämisestä. Näitä kaikkia käytettiin lopullisen tuotoksen valmistumiseen. Toteutuksen arviointina toimi tapahtumaan osallistuneilta saatu kirjallinen palaute. Palautteen mukaan kehittämistehtävän toteutuksessa onnistuttiin hyvin, sillä opinnäytetyön ennalta määritellyt tavoitteet saavutettiin. Opinnäytetyötä voidaan käyttää apuna jatkossa vastaavien tapahtumien suunnittelussa.Abstract Authors: Paananen Riina & Korkiakoski Merika Title of the Publication: Basics of wine tasting- event Degree title: Bachelor of Hospitality Management Keywords: event, wine, tasting, Chile The purpose for this thesis was to plan and arrange Basics of wine tasting –event. The commissioner for this thsesis was a local bar in Kajaani called Viinibaari Maria P. The event was planned to suit the imago of the bar. The objective of the thesis was to gain more customers to Viinibaari Maria P by introducing various wines to novice wine tasters. This research was a functional thesis which produced the Basics wine tasting event. The theory of this thesis focused on wine tasting, combining wine and food, Chile as a wine producer, and on planning and arranging an event. The feedback for the execution consists of the feedback forms that the customers of the event were asked to fill in. In addition observation method was used for evaluation. According to the feedback the event was successful because the objective of the thesis was reached. Our conclusion is that this thesis can be used as a guide in planning similar events

Deep Sequencing Whole Transcriptome Exploration of the σE Regulon in Neisseria meningitidis

Bacteria live in an ever-changing environment and must alter protein expression promptly to adapt to these changes and survive. Specific response genes that are regulated by a subset of alternative σ70-like transcription factors have evolved in order to respond to this changing environment. Recently, we have described the existence of a σE regulon including the anti-σ-factor MseR in the obligate human bacterial pathogen Neisseria meningitidis. To unravel the complete σE regulon in N. meningitidis, we sequenced total RNA transcriptional content of wild type meningococci and compared it with that of mseR mutant cells (ΔmseR) in which σE is highly expressed. Eleven coding genes and one non-coding gene were found to be differentially expressed between H44/76 wildtype and H44/76ΔmseR cells. Five of the 6 genes of the σE operon, msrA/msrB, and the gene encoding a pepSY-associated TM helix family protein showed enhanced transcription, whilst aniA encoding a nitrite reductase and nspA encoding the vaccine candidate Neisserial surface protein A showed decreased transcription. Analysis of differential expression in IGRs showed enhanced transcription of a non-coding RNA molecule, identifying a σE dependent small non-coding RNA. Together this constitutes the first complete exploration of an alternative σ-factor regulon in N. meningitidis. The results direct to a relatively small regulon indicative for a strictly defined response consistent with a relatively stable niche, the human throat, where N. meningitidis resides