35 research outputs found
Regulation of mtl operon promoter of Bacillus subtilis: requirements of its use in expression vectors
Several vector systems have been developed to express any gene desired to be studied in Bacillus subtilis. Among them, the transcriptionally regulated promoters involved in carbohydrate utilization are a research priority. Expression systems based on Bacillus promoters for xylose, maltose, and mannose utilization, as well as on the heterologous E. coli lactose promoter, have been successfully constructed. The promoter of the mtlAFD operon for utilization of mannitol is another promising candidate for its use in expression vectors. In this study, we investigated the regulation of the mtl genes in order to identify the elements needed to construct a strong mannitol inducible expression system in B. subtilis. Regulation of the promoters of Bacillus subtilis mtlAFD operon (PmtlA) and mtlR (PmtlR) encoding the activator were investigated by fusion to lacZ. Identification of the PmtlA and PmtlR transcription start sites revealed the sigma A like promoter structures. Also, the operator of PmtlA was determined by shortening, nucleotide exchange, and alignment of PmtlA and PmtlR operator regions. Deletion of the mannitol-specific PTS genes (mtlAF) resulted in PmtlA constitutive expression demonstrating the inhibitory effect of EIICBMtl and EIIAMtl on MtlR in the absence of mannitol. Disruption of mtlD made the cells sensitive to mannitol and glucitol. Both PmtlA and PmtlR were influenced by carbon catabolite repression (CCR). However, a CcpA deficient mutant showed only a slight reduction in PmtlR catabolite repression. Similarly, using PgroE as a constitutive promoter, putative cre sites of PmtlA and PmtlR slightly reduced the promoter activity in the presence of glucose. In contrast, glucose repression of PmtlA and PmtlR was completely abolished in a ptsG deletion mutant and significantly reduced in a MtlR (H342D) mutant
Lâintention de croissance des PME marocaines en contexte de crise
SMEs are the cornerstone of the Moroccan economy. They recruit, invest, and contribute strongly to economic growth. Indeed, the latter remains dependent on their growth and development. Nevertheless, contrary to what many people think, growth is not a common goal among SME managers. Some want to grow their businesses, while others are satisfied with the status quo. This research develops an in-depth analysis of the growth intention of Moroccan SMEs, while taking into account the crisis context in which it was conducted. In this sense, the study has two objectives: to understand through the eyes and perceptions of managers the impact that the crisis may have had on their business, and to understand their intention to grow during this context. After a literature review highlighting the role of the manager within the SME, and the results of the work on growth intention, we conducted, through a qualitative approach, four interviews with four Moroccan SME managers, located in Marrakech. The interviews, conducted between month 3 and month 4 of 2022, were transcribed according to the sociological method, and then analyzed by hand, through a horizontal and vertical analysis. Following this analysis, the results generated demonstrate that growth is a polyphonic concept, and that the intention to grow is protean: four modalities of the intention to grow have emerged. Strong growth intention, moderate growth intention, pending growth intention, and no growth intention. The results of this research contribute to the understanding of the perceptions of SME managers, which in return, would allow public authorities to put in place more adapted and therefore more useful support mechanisms in order to encourage them to grow.
JEL Classification: G01, L25, L1
Paper type: Empirical researchLes PME constituent la pierre angulaire de lâĂ©conomie marocaine. Elles recrutent, et investissent, et contribuent fortement dans la croissance Ă©conomique. En effet, ce dernier reste tributaire de leur croissance et dĂ©veloppement. NĂ©anmoins, contrairement Ă ce que pensent beaucoup de gens, la croissance nâest pas une finalitĂ© commune entre dirigeants des PME. Certains dĂ©sirent dĂ©velopper leurs entreprises, en revanche, dâautres sont satisfaits du statu quo. Cette recherche dĂ©veloppe une analyse en profondeur de lâintention de croissance des PME marocaines, tout en prenant en compte le contexte de crise oĂč elle a Ă©tĂ© menĂ©e. Dans ce sens, lâĂ©tude prĂ©sente un double objectif : Comprendre Ă travers lâĆil et perception des dirigeants lâimpact quâa pu avoir la crise sur leur activitĂ©, et apprĂ©hender leur intention de croissance durant ce contexte. AprĂšs une revue de littĂ©rature mettant la lumiĂšre sur le rĂŽle du dirigeant au sein de la PME, ainsi que sur les rĂ©sultats des travaux portant sur lâintention de croissance, nous avons menĂ©, Ă travers une approche qualitative, quatre entretiens auprĂšs de quatre dirigeants de PME marocaines, situĂ©es Ă Marrakech. Les entretiens conduits entre le mois 3 et le mois 4 de lâannĂ©e 2022, ont Ă©tĂ© retranscrits selon la mĂ©thode sociologique, puis analysĂ©e Ă la main, Ă travers une analyse horizontale et verticale. Ă la suite de cette analyse, les rĂ©sultats gĂ©nĂ©rĂ©s dĂ©montrent que la croissance est un concept polyphonique, et que lâintention de croissance est protĂ©iforme : quatre modalitĂ©s de lâintention de croissance ont Ă©mergĂ©. Lâintention de croissance forte, lâintention de croissance modĂ©rĂ©e, lâintention de croissance en suspens, et lâintention de non-croissance. Les rĂ©sultats de cette recherche contribuent dans la comprĂ©hension des perceptions des dirigeants des PME, ce qui par consĂ©quent, permettrait aux pouvoirs publics de mettre en place des dispositifs dâappui plus adaptĂ©s et donc plus utiles, afin de les encourager Ă se dĂ©velopper.
Classification JEL : G01, L25, L1
Type de lâarticle : Recherche appliquĂ©
Deletion of Rap-phosphatases for quorum sensing control in Bacillus and its effect on surfactin production
The complex regulatory network in Bacillus, known as quorum sensing, offers many opportunities to modify bacterial gene expression and hence to control bioprocesses. One target regulated by this mechanism is the activity of the PsrfA promoter, which is engaged in the formation of lipopeptide surfactin. It was hypothesised that deletion of rapC, rapF and rapH, encoding for prominent Rap-phosphatases known to affect PsrfA activity, would enhance surfactin production. Therefore, these genes were deleted in a sfp + derivative of B. subtilis 168 with subsequent evaluation of quantitative data. Up to the maximum product formation of the reference strain B. subtilis KM1016 after 16Â h of cultivation, the titers of the rap deletion mutants did not exceed the reference. However, an increase in both product yield per biomass Y P/X and specific surfactin productivity q surfactin was observed, without any considerable effect on the ComX activity. By extending the cultivation time, a 2.7-fold increase in surfactin titer was observed after 24Â h for strain CT10 (ÎrapC) and a 2.5-fold increase for CT11 (ÎrapF) compared to the reference strain KM1016. In addition, Y P/X was again increased for strains CT10 and CT11, with values of 1.33Â g/g and 1.13Â g/g, respectively. Interestingly, the effect on surfactin titer in strain CT12 (ÎrapH) was not as distinct, although it achieved the highest promoter activity (PsrfA-lacZ). The data presented support the possibility of involving the quorum sensing system of Bacillus in bioprocess control as shown here on the example of lipopeptide production.</p
Composition of liquid ion exchangers
SIGLEAvailable from British Library Document Supply Centre- DSC:D31907/80 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
La mĂ©moire de la guerre dans le roman contemporain de langue française : discontinuitĂ© et dislocation narratives dans les Ćuvres dâHenry Bauchau, dâAndrĂ©e Chedid et dâAnna MoĂŻ
Texte intĂ©gral accessible uniquement aux membres de l'UniversitĂ© de Lorraine jusqu'au 01 septembre 2025The present research considers some aspects of dislocated writing under the influence of the memory of war in the contemporary French-language novel. The study favours a narratological approach in three novels: Anna MoĂŻ's Riz noir, AndrĂ©e Chedid's Le Message and Henry Bauchau's Le Boulevard pĂ©riphĂ©rique. The choice of this corpus gives an overview of three different wars that occurred in the world. However, our study focuses on the tragic impact of war in general on three novels that, albeit being from the extreme-contemporary and coming from different nations, remind the twentieth century. This study aims to analyze how the authors succeed in transmitting the trauma of war, which raises the issues of discontinued and dislocated writing llustrating the hesitations or even the obsessions of an intermittent memory. In the first part, the thesis will focus mainly on the socio-historical changes of the turn of the 21st century and on the perception of a fragmented world, especially in the novel. The second and third parts, mostly emphasizing on narratological aspects, analyze the considered novels as memorial writings and examine the phenomena of a discontinued temporality as well as dislocated space in the composition of the three novels. The fourth part will present an overview of the composition of the novels and will examine the unifying processes ensuring the coherence of the novel. It will focus on the world of values present in the three studied novels evoking the axiological aspects of the novels and their ethical dimension towards war in order to give the reader the idea of a coherent reconstruction of a tragic History.Ce travail envisage les enjeux d'une narration discontinue et disloquĂ©e sous l'influence de la mĂ©moire de la guerre dans le roman contemporain de langue française. Elle privilĂ©gie une approche narratologique pour lâanalyse de trois romans : Le Message dâAndrĂ©e Chedid (2000), Riz noir dâAnna MoĂŻ (2004), Le Boulevard pĂ©riphĂ©rique de Henry Bauchau (2008). Le choix du corpus donne un aperçu gĂ©nĂ©ral sur trois guerres diffĂ©rentes dans le monde ; cependant, notre Ă©tude sâintĂ©ressera plutĂŽt Ă lâimpact tragique de la guerre, en gĂ©nĂ©ral, sur trois Ćuvres qui, tout en relevant de lâextrĂȘme-contemporain et venant de nations diffĂ©rentes, se souviennent du XXe siĂšcle. Ici, lâenjeu de lâanalyse est de montrer comment l'auteur rĂ©ussit Ă transmettre le traumatisme de la guerre, ce qui soulĂšve, dĂšs lors, des enjeux de la narration discontinue et disloquĂ©e, qui suit les hĂ©sitations, voir les obsessions d'une mĂ©moire intermittente. Dans une premiĂšre partie, la thĂšse se concentrera sur les mutations socio-historiques du tournant du XXIe siĂšcle et sur la perception dâun monde Ă©clatĂ©, spĂ©cialement dans le domaine romanesque. La deuxiĂšme et la troisiĂšme partie, essentiellement narratologiques, Ă©tudieront les romans considĂ©rĂ©s en tant quâĂ©critures mĂ©morielles et y examineront les phĂ©nomĂšnes de dislocation narrative dans lâorganisation du temps et de lâespace des rĂ©cits. La quatriĂšme partie, prĂ©sentera une vue d'ensemble sur la composition des romans et examinera les procĂ©dures dâunification relative assurant la cohĂ©rence romanesque. Nous nous intĂ©resserons, ici, aux univers de valeurs inscrits dans les trois romans Ă lâĂ©tude ; ce qui nous amĂšnera Ă Ă©voquer leurs aspects axiologiques et leur dimension Ă©thique face Ă la guerre, destinĂ©s Ă donner au lecteur l'idĂ©e d'une recomposition d'une Histoire tragique
Memory of war in contemporary French language novel : narrative discontinuity and dislocation in the novel of Henry Bauchau, Andrée Chedid and Anna Moï
Ce travail envisage les enjeux d'une narration discontinue et disloquĂ©e sous l'influence de la mĂ©moire de la guerre dans le roman contemporain de langue française. Elle privilĂ©gie une approche narratologique pour lâanalyse de trois romans : Le Message dâAndrĂ©e Chedid (2000), Riz noir dâAnna MoĂŻ (2004), Le Boulevard pĂ©riphĂ©rique de Henry Bauchau (2008). Le choix du corpus donne un aperçu gĂ©nĂ©ral sur trois guerres diffĂ©rentes dans le monde ; cependant, notre Ă©tude sâintĂ©ressera plutĂŽt Ă lâimpact tragique de la guerre, en gĂ©nĂ©ral, sur trois Ćuvres qui, tout en relevant de lâextrĂȘme-contemporain et venant de nations diffĂ©rentes, se souviennent du XXe siĂšcle. Ici, lâenjeu de lâanalyse est de montrer comment l'auteur rĂ©ussit Ă transmettre le traumatisme de la guerre, ce qui soulĂšve, dĂšs lors, des enjeux de la narration discontinue et disloquĂ©e, qui suit les hĂ©sitations, voir les obsessions d'une mĂ©moire intermittente. Dans une premiĂšre partie, la thĂšse se concentrera sur les mutations socio-historiques du tournant du XXIe siĂšcle et sur la perception dâun monde Ă©clatĂ©, spĂ©cialement dans le domaine romanesque. La deuxiĂšme et la troisiĂšme partie, essentiellement narratologiques, Ă©tudieront les romans considĂ©rĂ©s en tant quâĂ©critures mĂ©morielles et y examineront les phĂ©nomĂšnes de dislocation narrative dans lâorganisation du temps et de lâespace des rĂ©cits. La quatriĂšme partie, prĂ©sentera une vue d'ensemble sur la composition des romans et examinera les procĂ©dures dâunification relative assurant la cohĂ©rence romanesque. Nous nous intĂ©resserons, ici, aux univers de valeurs inscrits dans les trois romans Ă lâĂ©tude ; ce qui nous amĂšnera Ă Ă©voquer leurs aspects axiologiques et leur dimension Ă©thique face Ă la guerre, destinĂ©s Ă donner au lecteur l'idĂ©e d'une recomposition d'une Histoire tragique.The present research considers some aspects of dislocated writing under the influence of the memory of war in the contemporary French-language novel. The study favours a narratological approach in three novels: Anna MoĂŻ's Riz noir, AndrĂ©e Chedid's Le Message and Henry Bauchau's Le Boulevard pĂ©riphĂ©rique. The choice of this corpus gives an overview of three different wars that occurred in the world. However, our study focuses on the tragic impact of war in general on three novels that, albeit being from the extreme-contemporary and coming from different nations, remind the twentieth century. This study aims to analyze how the authors succeed in transmitting the trauma of war, which raises the issues of discontinued and dislocated writing llustrating the hesitations or even the obsessions of an intermittent memory. In the first part, the thesis will focus mainly on the socio-historical changes of the turn of the 21st century and on the perception of a fragmented world, especially in the novel. The second and third parts, mostly emphasizing on narratological aspects, analyze the considered novels as memorial writings and examine the phenomena of a discontinued temporality as well as dislocated space in the composition of the three novels. The fourth part will present an overview of the composition of the novels and will examine the unifying processes ensuring the coherence of the novel. It will focus on the world of values present in the three studied novels evoking the axiological aspects of the novels and their ethical dimension towards war in order to give the reader the idea of a coherent reconstruction of a tragic History
Regulation der Mannitol-Abbaugene in Bacillus subtilis
Bacillus subtilis takes up mannitol by a phosphoenolpyruvate-dependent phosphotransferase system (PTS). The mannitol utilization system is encoded by the mtlAFD operon consisting of mtlA (encoding membrane-bound EIICBMtl), mtlF (encoding phosphocarrier EIIAMtl), and mtlD (encoding mannitol 1-phosphate dehydrogenase). This operon is activated by MtlR whose coding gene is located approx. 14.4 kb downstream of the operon. The regulation of the mannitol utilization genes in B. subtilis was studied by fusion of the promoters of mtlAFD (PmtlA) and mtlR (PmtlR) to lacZ as a reporter gene. Both the PmtlA and PmtlR were inducible by mannitol and glucitol, while glucose reduced their activities. The promoter strength of PmtlA was about 4.5-fold higher than that of PmtlR. Identification of the transcription start sites of PmtlA and PmtlR revealed that both of these promoters contain a sigma A-type promoter structure. The promoter -35 and -10 boxes in PmtlA were TTGTAT and TAACAT and in PmtlR TTGATT and TATATT, respectively. Catabolite responsive elements (cre) were detected in the sequences of PmtlA and PmtlR overlapping the -10 boxes. Shortening the mRNA 5âuntranslated region (5âUTR) increased the PmtlA activity, whereas PmtlR activity was decreased by shortening of its mRNA 5âUTR. Alignment of the -35 upstream sequences of PmtlA and PmtlR revealed the putative MtlR binding site. This sequence comprised a similar incomplete inverted repeat in both the PmtlA and PmtlR sequences (TTGNCACAN4TGTGNCAA). This sequence was encompassed by two 11 bp distal and proximal flanking sequences. Construction of PmtlA-PlicB hybrid promoters and shortening of the 5â-end of PmtlA indicated the probable boundaries of putative MtlR binding site in PmtlA. Increasing the distance between the putative MtlR binding site and -35 box lowered the PmtlA maximal activity, although PmtlA remained inducible by mannitol. PmtlA became inactive by disruption of the TTGNCACAN4TGTGNCAA sequence. In contrast, manipulation of the distal and proximal flanking sequences only reduced the maximal activity of PmtlA, whereas PmtlA remained highly inducible. These flanking sequences contained AT-rich repeats similar to the consensus sequence of alpha CTD binding sites.
Regulation of PmtlA and PmtlR was investigated by deletion of mtlAF, mtlF, mtlD, and mtlR. Deletion of the mtlAF genes rendered PmtlA and PmtlR constitutive showing the inhibitory effect of EIICBMtl and EIIAMtl (PTS transporter components) on MtlR in the absence of mannitol. The constitutive activity of PmtlA was increased by the deletion of mtlF. In contrast, the deletion of mtlAFD showed a significant reduction in the PmtlA constitutive activity. Disruption of mtlD made B. subtilis sensitive to mannitol in a way that addition of mannitol or glucitol to the bacterial culture ended in cell lysis. Besides, PmtlA and PmtlR were similarly induced by glucitol and mannitol in a mtlD::erm mutant. Also, deletion of mtlR rendered PmtlA and PmtlR uninducible by mannitol or glucitol. In contrast, deletion of the glucitol utilization genes had no influence on the inducibility of PmtlA or PmtlR by glucitol. The PmtlA activity was drastically reduced in ptsH-H15A (HPr-H15A) mutant similar to the delta mtlR mutant. The mutation of histidine 289 in the PRDI domain of MtlR to alanine reduced the activity of PmtlA, whereas the PmtlA activity in the mtlR H230A mutant was almost similar to wild type. In contrast, mutation of the PRDII domain of MtlR to H342D mainly relieved PmtlA from glucose repression. Moreover, MtlR double mutant H342D C419A which was produced in E. coli was shown to be active in vitro. These results represent the positive regulation of MtlR via phosphorylation of the PRDII domain by HPr(H15~P). Also, dephosphorylation of the domains EIIBGat- and EIIAMtl-like of MtlR by EIIAMtl and EIICBMtl transporter components causes activation. The PmtlA activity was repressed in the presence of glucose and fructose, while sucrose and mannose had no influence on the PmtlA activity. Therefore, catabolite repression of PmtlA and PmtlR were studied by CcpA-dependent carbon catabolite repression mutants, such as ptsH-S46A, delta crh, delta hprK, and delta ccpA. Induction of PmtlA and PmtlR in these mutants did not result in a complete loss of catabolite repression. Therefore, the catabolite responsive elements (cre sites) of PmtlA and PmtlR were investigated. Using a constitutive promoter, PgroE, it was shown that the cre sites of PmtlA and PmtlR were weakly functional. In contrast, deletion of the glucose PTS transporter, encoded by ptsG, resulted in a complete loss of glucose repression in PmtlA and PmtlR. Thus, the main glucose repression of mannitol PTS function at the posttranslational level in a HPr-mediated manner via MtlR-H342 and at transcriptional level by CcpA-dependent carbon catabolite repression.Bacillus subtilis nimmt Mannitol mit Hilfe eines Phosphoenolpyruvat-abhĂ€ngigem Phosphotransferasesystems auf. Dieses wird durch das mtlAFD-Operon codiert, welches aus mtlA (codiert das Membran-gebundene EIICBMtl), mtlF (codiert das Phosphorylgruppen-ĂŒbertragende EIIAMtl) und mtlD (codiert die Mannitol-1-phosphat-Dehydrogenase) besteht. Das Operon wird durch MtlR aktiviert, dessen Gen ca. 14,4 kb stromabwĂ€rts des Operons lokalisiert ist. Die Regulation der Gene fĂŒr die Mannitol-Verwertung in B. subtilis wurde mit Hilfe des Reportergens lacZ untersucht, welches an die Promotoren vom mtlAFD (PmtlA) sowie mtlR (PmtlR) fusioniert wurde. Sowohl PmtlA als auch PmtlR wurden durch Mannitol und Glucitol induziert, wĂ€hrend Glucose die PromotoraktivitĂ€ten reprimierte. Im Vergleich zu PmtlR zeigte PmtlA eine ca. 4,5-fach höhere PromotorstĂ€rke. Die Analyse der Transkriptionsinitiations-Sequenzen durch Transkriptionsstartbestimmung von PmtlA und PmtlR ergab, dass es sich um Sigma A-abhĂ€ngige Promotoren handelt. Die -35 und -10 Promotorsequenzen von PmtlA und PmtlR wurden als TTGTAT und TAACAT bzw. TTGATT und TATATT identifiziert. In beiden Promotoren wurden cre- Sequenzen (catabolite responsive element) gefunden, welche mit den -10 Regionen ĂŒberlappen. Eine VerkĂŒrzung der 5â-untranslatierten Region (5âUTR) von PmtlA erhöhte dessen AktivitĂ€t, wohingegen die AktivitĂ€t von PmtlR durch die VerkĂŒrzung der 5âUTR reduziert wurde. Durch Sequenzalignment der stromaufwĂ€rts von PmtlA und PmtlR gelegenen Sequenzen konnte die mutmaĂliche MtlR-Bindestelle identifiziert werden. Diese Bindestelle ist in beiden Sequenzen durch eine unvollstĂ€ndig ausgeprĂ€gte, invertierte Wiederholungssequenz (TTGNCACAN4TGTGNCAA) charakterisiert, welche ihrerseits von jeweils zwei 11 bp langen Sequenzen flankiert wird.
Die Regulation von PmtlA und PmtlR wurde mit Hilfe von mtlAF-, mtlF-, mtlD- und mtlR-Deletionen in B. subtilis untersucht. Die Deletion von mtlAF fĂŒhrte zu einer konstitutiven AktivitĂ€t von PmtlA und PmtlR, wodurch der inhibitorische Effekt von EIICBMtl und EIIAMtl (Untereinheiten des PTS-Transporters) auf MtlR bei Abwesenheit von Mannitol gezeigt werden konnte. Die konstitutive AktivitĂ€t von PmtlA wurde durch die Deletion von mtlF noch verstĂ€rkt. Im Gegensatz dazu verursachte die Deletion von mtlAFD eine signifikante Reduktion der konstitutiven AktivitĂ€t von PmtlA. Die Mutation von mtlD resultierte in einer SensitivitĂ€t von B. subtilis gegenĂŒber Mannitol und Glucitol. Kultivierung in Gegenwart dieser Zucker fĂŒhrte zu einer Lyse der Zellen. In der mtlD::erm Mutante wurden PmtlA und PmtlR durch Glucitol und Mannitol gleichermaĂen induziert. Ferner fĂŒhrte die Deletion von mtlR zu einer Uninduzierbarkeit von PmtlA und PmtlR mit Mannitol und Glucitol, wohingegen die Deletion der Gene fĂŒr die Glucitol-Verwertung keinen Einfluss auf die Induzierbarkeit von PmtlA und PmtlR mit Glucitol hatte. Wie auch in der Delta mtlR Mutante war die AktivitĂ€t von PmtlA in der ptsH-H15A (HPr-H15A) Mutante drastisch reduziert. Die Mutation des Histidin 289 in der PRDI-DomĂ€ne von MtlR zu einem Alanin reduzierte die AktivitĂ€t von PmtlA, wĂ€hrend die AktivitĂ€t von PmtlA in der mtlR-H230A-Mutante Ă€hnlich wie die des Wildtyps war. Im Gegensatz dazu fĂŒhrte die Mutation H342D der PRDII-DomĂ€ne von MtlR zu einer verminderten Glucose-Repression von PmtlA. Eine MtlR Doppelmutante H342D C419A wurde in E. coli produziert und ihre AktivitĂ€t in einem Gelmobilityshiftassay in vitro bestĂ€tigt. Diese Ergebnisse zeigen, dass MtlR einer, durch die Phosphorylierung der PRDII-DomĂ€ne durch HPr(H15~P) stattfindenden, positiven Regulation unterliegt. Ferner kann eine Aktivierung von MtlR durch eine Dephosphorylierung der EIIBGat- und EIIAMtl-Ă€hnlichen DomĂ€nen durch die EIIAMtl und EIICBMtl Transporter-Untereinheiten erreicht werden. Glucose und Fructose reprimieren die AktivitĂ€t von PmtlA wohingegen Saccharose und Mannose keinen Einfluss auf die PmtlA-AktivitĂ€t haben. Daher wurde die Kohlenstoff-Katabolit-Repression von PmtlA und PmtlR in CcpA-abhĂ€ngigen Mutanten, wie ptsH-S46A, Delta crh, Delta hprK und Delta ccpA, untersucht. Da eine Induktion von PmtlA und PmtlR in den Mutanten nicht zu einem vollstĂ€ndigen Verlust der Katabolit-Repression fĂŒhrte, wurden die cre-Sequenzen (catabolite responsive element) der beiden Promotoren untersucht. Mit Hilfe des konstitutiven Promotors PgroE wurde gezeigt, dass die cre-Sequenzen von PmtlA und PmtlR nur schwach funktionsfĂ€hig waren. Im Gegensatz dazu fĂŒhrte die Deletion des Glucose-PTS-Transporters, welcher von ptsG codiert wird, zu einem vollstĂ€ndigen Verlust der Glucose-Repression von PmtlA und PmtlR. Folglich wird die Repression des Mannitol-PTS durch Glucose hauptsĂ€chlich posttranslational durch HPr via MtlR-H342 und auf transkriptionaler Ebene durch eine CcpA-abhĂ€ngige Kohlenstoff-Katabolit-Repression vermittelt
ALBERT (Christiane) et KOUVOUAMA (Abel), dir., DĂ©territorialisation : effet de mode ou concept pertinent ? Pau : Presses de lâuniversitĂ© de Pau et des Pays de lâAdour, coll. Espaces, FrontiĂšres, MĂ©tissages, n °1, 2013, 142 p. â ISBN 2-35311-034-7
Recension de : BĂ©dĂ© Damien et Coulibaly Moussa (Ă©ds.), LâĂcriture fragmentaire dans les rĂ©cits de productions africaines contemporaines, Paris, LâHarmattan, « Espaces littĂ©raires », 2015, 226 p.
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Recension de : BĂ©dĂ© Damien et Coulibaly Moussa (Ă©ds.), LâĂcriture fragmentaire dans les rĂ©cits de productions africaines contemporaines, Paris, LâHarmattan, « Espaces littĂ©raires », 2015, 226 p.
International audienc