1,721,469 research outputs found
Surface layer protein SlpC expression in different growth modes of Lactobacillus brevis ATCC 14869
No full textMonilla bakteereilla on soluseinän ulkopuolella pintakerros, joka koostuu itsestään järjestäytyvistä, yleensä identtisistä proteiini- tai glykoproteiiniyksiköistä. Lactobacillus brevis ATCC 14869 -kannalta on löytynyt vapaasti kasvavissa eli planktonisissa soluissa kaksi pintakerrosproteiinia, SlpB ja SlpD. Myös kolmannen pintaproteiinin geeni slpC on löydetty, mutta itse proteiinia ei aikaisemman tutkimuksen planktonisissa olosuhteissa havaittu. On kuitenkin ollut viitteitä siitä, että SlpC-proteiinia saatetaan tuottaa L. brevis
-bakteerin muodostamissa biofilmeissä.
Tämän tutkimuksen tavoitteena oli tutkia pintakerrosproteiinien SlpB, SlpC ja SlpD ekspressiotasoja L. brevis -bakteerin eri kasvumuodoissa käyttäen proteomiikan ja molekyylimikrobiologian menetelmiä. Pintakerrosproteiineja tutkittiin sekä irrottamalla pintaproteiinit kemiallisesti SDS-polyakryyliamidigeelielektroforeesiä varten, että analysoimalla entsymaattisesti irrotetut pintaproteiinit LC-MS/MS -menetelmän label-free quantification (LFQ) -sovelluksella. Pintakerrosproteiinigeenien lähetti-RNA-tasoja tutkittiin reverse transcriptase droplet digital PCR (RT-ddPCR) -menetelmällä.
Tutkimuksessa havaittiin, että kaikkia kolmea pintakerrosproteiinia SlpB, SlpC ja SlpD ekspressoitiin L. brevis ATCC 14869 -kannassa. Pintaproteiinianalyysin perusteella SlpD oli yleisin pintaproteiini ja sen osuus oli yli kolmasosa kokonaisproteiinimäärästä, kun taas SlpC- ja SlpB-proteiinien osuudet olivat pienempiä. Pintakerrosproteiinit olivat selvästi erotettavissa geelielektroforeesissa. Kaikkien pintakerrosproteiinien lähetti-RNA:ta oli havaittavissa RT-ddPCR-menetelmällä; näistä slpD oli yleisin, kun taas slpB- ja slpC-määrät olivat pienempiä. Biofilmi- ja planktonisissa soluissa oli saman verran eri pintakerrosproteiineja sekä näiden lähetti-RNA:ta.
Tässä tutkimuksessa osoitettiin ensimmäistä kertaa SlpC-proteiinin ekspressio L. brevis ATCC 14869 -bakteerissa ja että ekspressiotasot ovat samat sekä biofilmi- että planktonisissa soluissa.Bacterial surface layers (S-layers) usually consist of a single protein or glycoprotein species and they form the outermost layer of many bacteria. Three S-layer protein genes have been found in Lactobacillus brevis ATCC 14869, but the expression of only two of them, slpB and slpD, has been described in planktonic conditions. Preliminary results have suggested that the third gene, slpC, may be expressed in biofilm cells.
The aim of this thesis was to study the expression of S-layer protein genes slpB, slpC and slpD in the different growth modes of L. brevis ATCC 14869. Surface proteins were detached both chemically for SDS-PAGE analysis and enzymatically for surfaceome analysis by LC-MS/MS and label-free quantification (LFQ). Messenger RNA transcript levels of the S-layer protein genes were analyzed by reverse transcriptase droplet digital PCR (RT-ddPCR).
The expression of all three S-layer protein genes slpB, slpC and slpD was confirmed in the study. In the surfaceome analysis, SlpD was the most abundant protein detected on the cell surface, representing more than a third of all identified proteins, whereas SlpB and SlpC were less abundant. The S-layer proteins were detected by gel electrophoresis. Transcripts of all three genes were observed; slpD transcript amounts were the highest, whereas slpB and slpC transcript amounts were lower. The S-layer proteins and their transcripts were present in equal amounts in biofilm and planktonic cells.
In this study, SlpC expression is demonstrated for the first time in L. brevis ATCC 14869. The expression of slpB, slpC and slpD was at the same level in biofilm and planktonic cells
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Characterization and complete genome sequences of L. rhamnosus DSM 14870 and L. gasseri DSM 14869 contained in the EcoVag® probiotic vaginal capsules
No full textLactobacillus rhamnosus DSM 14870 and Lactobacillus gasseri DSM 14869 were previously isolated from the vaginal epithelial cells (VEC) of healthy women and selected for the development of the vaginal EcoVag (R) probiotic capsules. EcoVag (R) was subsequently shown to provide long-term cure and reduce relapse of bacterial vaginosis (BV) as an adjunct to antibiotic therapy. To identify genes potentially involved in probiotic activity, we performed genome sequencing and characterization of the two strains. The complete genome analysis of both strains revealed the presence of genes encoding functions related to adhesion, exopolysaccharide (EPS) biosynthesis, antimicrobial activity, and CRISPR adaptive immunity but absence of antibiotic resistance genes. Interesting features of L. rhamnosus DSM 14870 genome include the presence of the spaCBA-srtC gene encoding spaCBA pill and interruption of the gene cluster encoding long galactose-rich EPS by integrases. Unique to L. gasseri DSM 14869 genome was the presence of a gene encoding a putative (1456 amino acid) new adhesin containing two rib/alpha-like repeats. L. rhamnosus DSM 14870 and L. gasseri DSM 14869 showed acidification of the culture medium (to pH 3.8) and a strong adhesion capability to the Caco-2 cell line and VEC. L gasseri DSM 14869 could produce a thick (40 nor) EPS layer and hydrogen peroxide. L. rhamnosus DSM 14870 was shown to produce SpaCBA pili and a 20 nor EPS layer, and could inhibit the growth of Gardnerella vaginalis, a bacterium commonly associated with BV. The genome sequences provide a basis for further elucidation of the molecular basis for their probiotic functions.</p
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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