Journal articles: 'CSRK'

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Baker, Carol S., Lél A. Eöry, Helen Yakhnin, Jeffrey Mercante, Tony Romeo, and Paul Babitzke. "CsrA Inhibits Translation Initiation of Escherichia coli hfq by Binding to a Single Site Overlapping the Shine-Dalgarno Sequence." Journal of Bacteriology 189, no. 15 (May 25, 2007): 5472–81. http://dx.doi.org/10.1128/jb.00529-07.

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ABSTRACT Csr (carbon storage regulation) of Escherichia coli is a global regulatory system that consists of CsrA, a homodimeric RNA binding protein, two noncoding small RNAs (sRNAs; CsrB and CsrC) that function as CsrA antagonists by sequestering this protein, and CsrD, a specificity factor that targets CsrB and CsrC for degradation by RNase E. CsrA inhibits translation initiation of glgC, cstA, and pgaA by binding to their leader transcripts and preventing ribosome binding. Translation inhibition is thought to contribute to the observed mRNA destabilization. Each of the previously known target transcripts contains multiple CsrA binding sites. A position-specific weight matrix search program was developed using known CsrA binding sites in mRNA. This search tool identified a potential CsrA binding site that overlaps the Shine-Dalgarno sequence of hfq, a gene that encodes an RNA chaperone that mediates sRNA-mRNA interactions. This putative CsrA binding site matched the SELEX-derived binding site consensus sequence in 8 out of 12 positions. Results from gel mobility shift and footprint assays demonstrated that CsrA binds specifically to this site in the hfq leader transcript. Toeprint and cell-free translation results indicated that bound CsrA inhibits Hfq synthesis by competitively blocking ribosome binding. Disruption of csrA caused elevated expression of an hfq′-′lacZ translational fusion, while overexpression of csrA inhibited expression of this fusion. We also found that hfq mRNA is stabilized upon entry into stationary-phase growth by a CsrA-independent mechanism. The interaction of CsrA with hfq mRNA is the first example of a CsrA-regulated gene that contains only one CsrA binding site.

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Fortune, Doreen R., Mitsu Suyemoto, and Craig Altier. "Identification of CsrC and Characterization of Its Role in Epithelial Cell Invasion in Salmonella enterica Serovar Typhimurium." Infection and Immunity 74, no. 1 (January 2006): 331–39. http://dx.doi.org/10.1128/iai.74.1.331-339.2006.

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ABSTRACT The csr regulatory system of Salmonella regulates the expression of the genes of Salmonella pathogenicity island 1 (SPI1) required for the invasion of epithelial cells. This system consists of the posttranscriptional regulator CsrA and an untranslated regulatory RNA, CsrB, that opposes the action of CsrA. Here we identify and characterize the role of a second regulatory RNA, CsrC, whose ortholog was discovered previously in Escherichia coli. We show that a mutant of csrC has only mild defects in invasion and the expression of SPI1 genes, as does a mutant of csrB, but that a double csrB csrC mutant is markedly deficient in these properties, suggesting that the two regulatory RNAs play redundant roles in the control of invasion. We further show that CsrC, like CsrB, is controlled by the BarA/SirA two-component regulator but that a csrB csrC mutant exhibits a loss of invasion equivalent to that of a barA or sirA mutant, indicating that much of the effect of BarA/SirA on invasion functions through its control of CsrB and CsrC. In addition to their control by BarA/SirA, each regulatory RNA is also controlled by other components of the csr system. The loss of csrB was found to increase the level of CsrC by sevenfold, while the loss of csrC increased CsrB by nearly twofold. Similarly, the overexpression of csrA increased CsrC by nearly 11-fold and CsrB by 3-fold and also significantly increased the stability of both RNAs.

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Pannuri, Archana, Christopher A. Vakulskas, Tesfalem Zere, Louise C. McGibbon, Adrianne N. Edwards, Dimitris Georgellis, Paul Babitzke, and Tony Romeo. "Circuitry Linking the Catabolite Repression and Csr Global Regulatory Systems of Escherichia coli." Journal of Bacteriology 198, no. 21 (August 22, 2016): 3000–3015. http://dx.doi.org/10.1128/jb.00454-16.

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ABSTRACTCyclic AMP (cAMP) and the cAMP receptor protein (cAMP-CRP) and CsrA are the principal regulators of the catabolite repression and carbon storage global regulatory systems, respectively. cAMP-CRP controls the transcription of genes for carbohydrate metabolism and other processes in response to carbon nutritional status, while CsrA binds to diverse mRNAs and regulates translation, RNA stability, and/or transcription elongation. CsrA also binds to the regulatory small RNAs (sRNAs) CsrB and CsrC, which antagonize its activity. The BarA-UvrY two-component signal transduction system (TCS) directly activatescsrBandcsrC(csrB/C) transcription, while CsrA does so indirectly. We show that cAMP-CRP inhibitscsrB/Ctranscription without negatively regulating phosphorylated UvrY (P-UvrY) or CsrA levels. Acrpdeletion caused an elevation in CsrB/C levels in the stationary phase of growth and increased the expression ofcsrB-lacZandcsrC-lacZtranscriptional fusions, although modest stimulation of CsrB/C turnover by thecrpdeletion partially masked the former effects. DNase I footprinting and other studies demonstrated that cAMP-CRP bound specifically to three sites located upstream from thecsrCpromoter, two of which overlapped the P-UvrY binding site. These two proteins competed for binding at the overlapping sites.In vitrotranscription-translation experiments confirmed direct repression ofcsrC-lacZexpression by cAMP-CRP. In contrast, cAMP-CRP effects oncsrBtranscription may be mediated indirectly, as it bound nonspecifically tocsrBDNA. In the reciprocal direction, CsrA bound tocrpmRNA with high affinity and specificity and yet exhibited only modest, conditional effects on expression. Our findings are incorporated into an emerging model for the response of Csr circuitry to carbon nutritional status.IMPORTANCECsr (Rsm) noncoding small RNAs (sRNAs) CsrB and CsrC ofEscherichia coliuse molecular mimicry to sequester the RNA binding protein CsrA (RsmA) away from lower-affinity mRNA targets, thus eliciting major shifts in the bacterial lifestyle. CsrB/C transcription and turnover are activated by carbon metabolism products (e.g., formate and acetate) and by a preferred carbon source (glucose), respectively. We show that cAMP-CRP, a mediator of classical catabolite repression, inhibitscsrCtranscription by binding to the upstream region of this gene and also inhibitscsrBtranscription, apparently indirectly. We propose that glucose availability activates pathways for both synthesis and turnover of CsrB/C, thus shaping the dynamics of global signaling in response to the nutritional environment by poising CsrB/C sRNA levels for rapid response.

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Carzaniga, Thomas, Federica A. Falchi, Francesca Forti, Davide Antoniani, Paolo Landini, and Federica Briani. "Different csrA Expression Levels in C versus K-12 E. coli Strains Affect Biofilm Formation and Impact the Regulatory Mechanism Presided by the CsrB and CsrC Small RNAs." Microorganisms 9, no. 5 (May 7, 2021): 1010. http://dx.doi.org/10.3390/microorganisms9051010.

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Escherichia coli C is a strong biofilm producer in comparison to E. coli K-12 laboratory strains due to higher expression of the pgaABCD operon encoding the enzymes for the biosynthesis of the extracellular polysaccharide poly-β-1,6-N-acetylglucosamine (PNAG). The pgaABCD operon is negatively regulated at the post-transcriptional level by two factors, namely CsrA, a conserved RNA-binding protein controlling multiple pathways, and the RNA exonuclease polynucleotide phosphorylase (PNPase). In this work, we investigated the molecular bases of different PNAG production in C-1a and MG1655 strains taken as representative of E. coli C and K-12 strains, respectively. We found that pgaABCD operon expression is significantly lower in MG1655 than in C-1a; consistently, CsrA protein levels were much higher in MG1655. In contrast, we show that the negative effect exerted by PNPase on pgaABCD expression is much stronger in C-1a than in MG1655. The amount of CsrA and of the small RNAs CsrB, CsrC, and McaS sRNAs regulating CsrA activity is dramatically different in the two strains, whereas PNPase level is similar. Finally, the compensatory regulation acting between CsrB and CsrC in MG1655 does not occur in E. coli C. Our results suggest that PNPase preserves CsrA-dependent regulation by indirectly modulating csrA expression.

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Teplitski, Max, Ali Al-Agely, and Brian M. M. Ahmer. "Contribution of the SirA regulon to biofilm formation in Salmonella enterica serovar Typhimurium." Microbiology 152, no. 11 (November 1, 2006): 3411–24. http://dx.doi.org/10.1099/mic.0.29118-0.

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Orthologues of the Salmonella enterica serovar Typhimurium (S. typhimurium) BarA/SirA two-component system are important for biofilm formation and virulence in many γ-Proteobacteria. In S. typhimurium, SirA activates the csrB and csrC carbon storage regulatory RNAs and the virulence gene regulators hilA and hilC. The regulatory RNAs antagonize the activity of the CsrA protein, allowing translation of those same virulence genes, and inhibiting the translation of flagellar genes. In this report, it was determined that SirA and the Csr system also control the fim operon that encodes type 1 fimbriae. sirA orthologues in other bacterial species, and the fim operon of S. typhimurium, are known to play a role in biofilm formation; therefore, all members of the S. typhimurium sirA regulon were tested for in vitro biofilm production. A sirA mutant, a csrB csrC double mutant, and a fimI mutant, were all defective in biofilm formation. Conversely, inactivation of flhDC increased biofilm formation. Therefore, SirA activates csrB, csrC and the fim operon to promote biofilm formation. In turn, csrB and csrC promote the translation of the fim operon, while at the same time inhibiting the translation of flagella, which are inhibitory to biofilm formation.

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Camacho, Martha I., Adrian F. Alvarez, Ricardo Gonzalez Chavez, Tony Romeo, Enrique Merino, and Dimitris Georgellis. "Effects of the Global Regulator CsrA on the BarA/UvrY Two-Component Signaling System." Journal of Bacteriology 197, no. 5 (December 22, 2014): 983–91. http://dx.doi.org/10.1128/jb.02325-14.

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The hybrid sensor kinase BarA and its cognate response regulator UvrY, members of the two-component signal transduction family, activate transcription of CsrB and CsrC noncoding RNAs. These two small RNAs act by sequestering the RNA binding protein CsrA, which posttranscriptionally regulates translation and/or stability of its target mRNAs. Here, we provide evidence that CsrA positively affects, although indirectly,uvrYexpression, at both the transcriptional and translational levels. We also demonstrate that CsrA is required for properly switching BarA from its phosphatase to its kinase activity. Thus, the existence of a feedback loop mechanism that involves the Csr and BarA/UvrY global regulatory systems is exposed.

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Gonzalez Chavez, Ricardo, Adrian F. Alvarez, Tony Romeo, and Dimitris Georgellis. "The Physiological Stimulus for the BarA Sensor Kinase." Journal of Bacteriology 192, no. 7 (January 29, 2010): 2009–12. http://dx.doi.org/10.1128/jb.01685-09.

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ABSTRACT The two-component signal transduction system (TCS) BarA/UvrY activates transcription of CsrB and CsrC noncoding RNAs, which act by sequestering the RNA-binding global regulatory protein CsrA. Here, we show that the metabolic end products formate and acetate provide a physiological stimulus for this TCS and thus link posttranscriptional regulation by the Csr system to the metabolic state of the cell.

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Shin, Jaemin, Hyun Geun Lee, and June-Yub Lee. "Long-time simulation of the phase-field crystal equation using high-order energy-stable CSRK methods." Computer Methods in Applied Mechanics and Engineering 364 (June 2020): 112981. http://dx.doi.org/10.1016/j.cma.2020.112981.

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Gudapaty, Seshagirirao, Kazushi Suzuki, Xin Wang, Paul Babitzke, and Tony Romeo. "Regulatory Interactions of Csr Components: the RNA Binding Protein CsrA Activates csrB Transcription inEscherichia coli." Journal of Bacteriology 183, no. 20 (October 15, 2001): 6017–27. http://dx.doi.org/10.1128/jb.183.20.6017-6027.2001.

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ABSTRACT The global regulator CsrA (carbon storage regulator) ofEscherichia coli is a small RNA binding protein that represses various metabolic pathways and processes that are induced in the stationary phase of growth, while it activates certain exponential phase functions. Both repression and activation by CsrA involve posttranscriptional mechanisms, in which CsrA binding to mRNA leads to decreased or increased transcript stability, respectively. CsrA also binds to a small untranslated RNA, CsrB, forming a ribonucleoprotein complex, which antagonizes CsrA activity. We have further examined the regulatory interactions of CsrA and CsrB RNA. The 5′ end of the CsrB transcript was mapped, and acsrB::cam null mutant was constructed. CsrA protein and CsrB RNA levels were estimated throughout the growth curves of wild-type and isogenic csrA,csrB, rpoS, or csrA rpoSmutant strains. CsrA levels exhibited modest or negligible effects of these mutations. The intracellular concentration of CsrA exceeded the total CsrA-binding capacity of intracellular CsrB RNA. In contrast, CsrB levels were drastically decreased (∼10-fold) in thecsrA mutants. CsrB transcript stability was unaffected by csrA. The expression of a csrB-lacZtranscriptional fusion containing the region from −242 to +4 bp of thecsrB gene was decreased ∼20-fold by acsrA::kanR mutation in vivo but was unaffected by CsrA protein in vitro. These results reveal a significant, though most likely indirect, role for CsrA in regulatingcsrB transcription. Furthermore, our findings suggest that CsrA mediates an intriguing form of autoregulation, whereby its activity, but not its levels, is modulated through effects on an RNA antagonist, CsrB.

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Suzuki, Kazushi, Xin Wang, Thomas Weilbacher, Anna-Karin Pernestig, Öjar Melefors, Dimitris Georgellis, Paul Babitzke, and Tony Romeo. "Regulatory Circuitry of the CsrA/CsrB and BarA/UvrY Systems of Escherichia coli." Journal of Bacteriology 184, no. 18 (September 15, 2002): 5130–40. http://dx.doi.org/10.1128/jb.184.18.5130-5140.2002.

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ABSTRACT The global regulator CsrA (carbon storage regulator) is an RNA binding protein that coordinates central carbon metabolism, activates flagellum biosynthesis and motility, and represses biofilm formation in Escherichia coli. CsrA activity is antagonized by the untranslated RNA CsrB, to which it binds and forms a globular ribonucleoprotein complex. CsrA indirectly activates csrB transcription, in an apparent autoregulatory mechanism. In the present study, we elucidate the intermediate regulatory circuitry of this system. Mutations affecting the BarA/UvrY two-component signal transduction system decreased csrB transcription but did not affect csrA′-′lacZ expression. The uvrY defect was severalfold more severe than that of barA. Both csrA and uvrY were required for optimal barA expression. The latter observation suggests an autoregulatory loop for UvrY. Ectopic expression of uvrY suppressed the csrB-lacZ expression defects caused by uvrY, csrA, or barA mutations; csrA suppressed csrA or barA defects; and barA complemented only the barA mutation. Purified UvrY protein stimulated csrB-lacZ expression approximately sixfold in S-30 transcription-translation reactions, revealing a direct effect of UvrY on csrB transcription. Disruption of sdiA, which encodes a LuxR homologue, decreased the expression of uvrY′-′lacZ and csrB-lacZ fusions but did not affect csrA′-′lacZ. The BarA/UvrY system activated biofilm formation. Ectopic expression of uvrY stimulated biofilm formation by a csrB-null mutant, indicative of a CsrB-independent role for UvrY in biofilm development. Collectively, these results demonstrate that uvrY resides downstream from csrA in a signaling pathway for csrB and that CsrA stimulates UvrY-dependent activation of csrB expression by BarA-dependent and -independent mechanisms.

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Lee, Jae Hoon, Veronica Ancona, Tiyakhon Chatnaparat, Ho-wen Yang, and Youfu Zhao. "The RNA-Binding Protein CsrA Controls Virulence in Erwinia amylovora by Regulating RelA, RcsB, and FlhD at the Posttranscriptional Level." Molecular Plant-Microbe Interactions® 32, no. 10 (October 2019): 1448–59. http://dx.doi.org/10.1094/mpmi-03-19-0077-r.

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CsrA, an RNA-binding protein, binds to target transcripts and alters their translation or stability. In Erwinia amylovora, CsrA positively regulates the expression of type III secretion system (T3SS), exopolysaccharide amylovoran, and motility. In this study, the global effect of CsrA and its noncoding small RNA (ncsRNA) csrB in E. amylovora was determined by RNA-seq, and potential molecular mechanisms of CsrA-dependent virulence regulation were examined. Transcriptomic analyses under the T3SS-inducing condition revealed that mutation in the csrA gene led to differential expression of more than 20% of genes in the genome. Among them, T3SS genes and those required for cell growth and viability were significantly downregulated. On the other hand, the csrB mutant exhibited significant upregulation of most major virulence genes, suggesting an antagonistic effect of csrB on CsrA targets. Direct interaction between CsrA protein and csrB was further confirmed through the RNA electrophoretic mobility shift assay (REMSA). However, no direct interaction between CsrA and hrpL and hrpS transcripts was detected, suggesting that HrpL and HrpS are not targets of CsrA, whereas three CsrA targets (relA, rcsB, and flhD) were identified and confirmed by REMSA, site-directed mutagenesis, and LacZ reporter gene assays. These findings might partially explain how CsrA positively controls E. amylovora virulence by targeting major regulators at the posttranscriptional level.

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Jiang, Sheng-Mei, Nadeeza Ishmael, Julie Dunning Hotopp, Manuela Puliti, Luciana Tissi, Nikhil Kumar, Michael J. Cieslewicz, Hervé Tettelin, and Michael R. Wessels. "Variation in the Group B Streptococcus CsrRS Regulon and Effects on Pathogenicity." Journal of Bacteriology 190, no. 6 (January 18, 2008): 1956–65. http://dx.doi.org/10.1128/jb.01677-07.

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ABSTRACT CsrRS (or CovRS) is a two-component regulatory system that controls expression of multiple virulence factors in the important human pathogen group B Streptococcus (GBS). We now report global gene expression studies in GBS strains 2603V/R and 515 and their isogenic csrR and csrS mutants. Together with data reported previously for strain NEM316, the results reveal a conserved 39-gene CsrRS regulon. In vitro phosphorylation-dependent binding of recombinant CsrR to promoter regions of both positively and negatively regulated genes suggests that direct binding of CsrR can mediate activation as well as repression of target gene expression. Distinct patterns of gene regulation in csrR versus csrS mutants in strain 2603V/R compared to 515 were associated with different hierarchies of relative virulence of wild-type, csrR, and csrS mutants in murine models of systemic infection and septic arthritis. We conclude that CsrRS regulates a core group of genes including important virulence factors in diverse strains of GBS but also displays marked variability in the repertoire of regulated genes and in the relative effects of CsrS signaling on CsrR-mediated gene regulation. Such variation is likely to play an important role in strain-specific adaptation of GBS to particular host environments and pathogenic potential in susceptible hosts.

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Longère, Benjamin, Christos V. Gkizas, Augustin Coisne, Lucas Grenier, Valentina Silvestri, Julien Pagniez, Arianna Simeone, et al. "60-S Retrogated Compressed Sensing 2D Cine of the Heart: Sharper Borders and Accurate Quantification." Journal of Clinical Medicine 10, no. 11 (May 29, 2021): 2417. http://dx.doi.org/10.3390/jcm10112417.

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Background and objective: Real-time compressed sensing cine (CSrt) provides reliable quantification for both ventricles but may alter image quality. The aim of this study was to assess image quality and the accuracy of left (LV) and right ventricular (RV) volumes, ejection fraction and mass quantifications based on a retrogated segmented compressed sensing 2D cine sequence (CSrg). Methods: Thirty patients were enrolled. Each patient underwent the reference retrogated segmented steady-state free precession cine sequence (SSFPref), the real-time CSrt cine and the segmented retrogated prototype CSrg sequence providing the same slices. Functional parameters quantification and image quality rating were performed on SSFPref and CSrg images sets. The edge sharpness, which is an estimate of the edge spread function, was assessed for the three sequences. Results: The mean scan time was: SSFPref = 485.4 ± 83.3 (SD) s (95% CI: 454.3–516.5) and CSrg = 58.3 ± 15.1 (SD) s (95% CI: 53.7–64.2) (p < 0.0001). CSrg subjective image quality score (median: 4; range: 2–4) was higher than the one provided by CSrt (median: 3; range: 2–4; p = 0.0008) and not different from SSFPref overall quality score (median: 4; range: 2–4; p = 0.31). CSrg provided similar LV and RV functional parameters to those assessed with SSFPref (p > 0.05). Edge sharpness was significantly better with CSrg (0.083 ± 0.013 (SD) pixel−1; 95% CI: 0.078–0.087) than with CSrt (0.070 ± 0.011 (SD) pixel−1; 95% CI: 0.066–0.074; p = 0.0004) and not different from the reference technique (0.075 ± 0.016 (SD) pixel−1; 95% CI: 0.069–0.081; p = 0.0516). Conclusions: CSrg cine provides in one minute an accurate quantification of LV and RV functional parameters without compromising subjective and objective image quality.

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Bhattacharyya, Som Sekhar, and Surabhi Verma. "Firm–civil society organizational collaborations in the context of corporate social responsibility (CSR) initiatives; development of collaboration typology." World Journal of Entrepreneurship, Management and Sustainable Development 16, no. 4 (September 14, 2020): 359–75. http://dx.doi.org/10.1108/wjemsd-12-2019-0101.

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PurposeBusiness firms operate in society not only for market gains but also for generating positive social externalities. Civil society organisations (CSO) have helped society to develop across various spheres of influence. The concept of corporate social responsibility (CSR) ushered in an era wherein both business economic objectives as well as socio-environmental responsibilities of firms were prioritized simultaneously. The path of firms and CSOs intersected through CSR. In this work, the authors develop a typology on firm–CSO collaboration regarding CSR initiatives.Design/methodology/approachThe authors through a twin approach of systematic literature review (SLR) with qualitative study developed a categorization of collaborations between a firm and a CSO in the context of CSR engagements. Apart from the SLR, the authors undertook two focus group discussions (FGD) with CSR experts (engaged in firm–CSO collaboration). This was done with a semi-structured discussion agenda frame. The data were content analysed for thematic aspects. Thus, both SLR as well as FGD outputs were considered for the study results.FindingsThe authors found six elements in firm–CSO collaboration and seven archetypes of collaboration. The six elements were CSR action elements (CSRAE) consisting of CSR agenda (CSRA), CSR resources (CSRR), CSR capabilities (CSRC), CSR Pprocess (CSRP), CSR monitoring (CSRM) and CSR stakeholder engagement (CSRSE). The seven typologies were CSO as auditor , outsourcing of CSR , CSO-driven CSR, joint CSR, support to CSO for CSR ,guided support to CSO and coordinated CSR.Research limitations/implicationsDoty and Glick, (1994) had undertaken a seminal work on theory building based upon the unique method of application of typologies. Doty and Glick, (1994) elucidated how application of typologies could through a typology study enhance the scope and level for understanding and modelling in a contextual domain involving theory. This study was a step in this direction in the context of firm–CSO collaboration in the context of CSR initiatives.Practical implicationsThis study would help managers from both CSOs and business firms to comprehend in which sphere they were required to collaborate like in resource /capabilities deployment or in designing CSR agendas or CSR process or CSR monitoring or in stakeholder engagement during CSR management. This typology would enable managers to comprehend what would be the most suitable form of collaboration between a firm and a CSO for a specific CSR engagement.Originality/valueThis is one of the first studies that theorizes regarding firm–CSO collaboration in the context of CSR initiatives both in terms of the collaboration building block elements as well as typology presented.

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Teplitski, Max, Robert I. Goodier, and Brian M. M. Ahmer. "Pathways Leading from BarA/SirA to Motility andVirulence Gene Expression inSalmonella." Journal of Bacteriology 185, no. 24 (December 15, 2003): 7257–65. http://dx.doi.org/10.1128/jb.185.24.7257-7265.2003.

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ABSTRACT The barA and sirA genes of Salmonella enterica serovar Typhimurium encode a two-component sensor kinase and a response regulator, respectively. This system increases the expression of virulence genes and decreases the expression of motility genes. In this study, we examined the pathways by which SirA affects these genes. We found that the master regulator of flagellar genes, flhDC, had a positive regulatory effect on the primary regulator of intestinal virulence determinants, hilA, but that hilA had no effect on flhDC. SirA was able to repress flhDC in a hilA mutant and activate hilA in an flhDC mutant. Therefore, although the flhDC and hilA regulatory cascades interact, sirA affects each of them independently. A form of BarA lacking the two N-terminal membrane-spanning domains, BarA198, autophosphorylates in the presence of ATP and transfers the phosphate to purified SirA. Phosphorylated SirA was found to directly bind the hilA and hilC promoters in gel mobility shift assays but not the flhD, fliA, hilD, and invF promoters. Given that the CsrA/csrB system is known to directly affect flagellar gene expression, we tested the hypothesis that SirA affects flagellar gene expression indirectly by regulating csrA or csrB. The sirA gene did not regulate csrA but did activate csrB expression. Consistent with these results, phosphorylated SirA was found to directly bind the csrB promoter but not the csrA promoter. We propose a model in which SirA directly activates virulence expression via hilA and hilC while repressing the flagellar regulon indirectly via csrB.

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Frederick, William C. "From CSR1 to CSR2." Business & Society 33, no. 2 (August 1994): 150–64. http://dx.doi.org/10.1177/000765039403300202.

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Jiang, Sheng-Mei, Michael J. Cieslewicz, Dennis L. Kasper, and Michael R. Wessels. "Regulation of Virulence by a Two-Component System in Group B Streptococcus." Journal of Bacteriology 187, no. 3 (February 1, 2005): 1105–13. http://dx.doi.org/10.1128/jb.187.3.1105-1113.2005.

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ABSTRACT Group B Streptococcus (GBS) is frequently carried in the gastrointestinal or genitourinary tract as a commensal organism, yet it has the potential to cause life-threatening infection in newborn infants, pregnant women, and individuals with chronic illness. Regulation of virulence factor expression may affect whether GBS behaves as an asymptomatic colonizer or an invasive pathogen, but little is known about how such factors are controlled in GBS. We now report the characterization of a GBS locus that encodes a two-component regulatory system similar to CsrRS (or CovRS) in Streptococcus pyogenes. Inactivation of csrR, encoding the putative response regulator, in two unrelated wild-type strains of GBS resulted in a marked increase in production of beta-hemolysin/cytolysin and a striking decrease in production of CAMP factor, an unrelated cytolytic toxin. Quantitative RNA hybridization experiments revealed that these two phenotypes were associated with a marked increase and decrease in expression of the corresponding genes, cylE and cfb, respectively. The CsrR mutant strains also displayed increased expression of scpB encoding C5a peptidase. Similar, but less marked, changes in gene expression were observed in CsrS (putative sensor component) mutants, evidence that CsrR and CsrS constitute a functional two-component system. Experimental infection studies in mice demonstrated reduced virulence of both CsrR and CsrS mutant strains relative to the wild type. Together, these results indicate that CsrRS regulates expression of multiple GBS virulence determinants and is likely to play an important role in GBS pathogenesis.

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Abubakar, Ahmed, Sani Ahmed Yauta, and Mohammed Mahmud Khalifa. "Corporate Social Responsibility (CSR): Strategy for University Sustainable Competitive Advantage." Business Management and Strategy 13, no. 2 (July 3, 2022): 19. http://dx.doi.org/10.5296/bms.v13i2.19294.

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Corporate Social Responsibility (CSR) is generally presumed to be associated with companies in the full sense of the word, overlooking the important role of other institutions and organizations in achieving the objectives of the concept of CSR. This study's goal is to scientifically evaluate the link between corporate social responsibility and a university's sustainable competitive advantage. A conceptual model was created based on strategic corporate social innovation literature. The research was quantitative, and the variables were measured using the literature guide to build the research questionnaire. The analysis used structural equation modelling and the result revealed that Corporate Social Responsibility in relation to Customers or/and Students (CSRCS), Employees (CSRE), Government (CSRG) and Social stakeholders (CSRS) has a major impact on a university's sustained competitive advantage. Management and employees at universities can learn how to apply differentiation techniques to address community issues related to healthcare, economic, sociocultural, and environmental. For quality research and community outreach that better fulfill social needs, innovative, quality-based approaches must be developed. The study extends the existing literature by empirically validating the relationship between CSR and a university's sustainable comparative advantage.

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Aubee, Joseph I., Alexandria Adigun, Kirsten R. Branch, Ava C. Conyer, Olufolakemi Olusanya, Kinlyn Williams, and Karl M. Thompson. "467 Post-transcriptional regulation of the MiaA prenyl transferase by the small RNA CsrB in Escherichia coli (E. coli)." Journal of Clinical and Translational Science 6, s1 (April 2022): 93. http://dx.doi.org/10.1017/cts.2022.274.

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OBJECTIVES/GOALS: MiaA is a highly conserved prenyl transferase that catalyzes synthesis of the i6A37 tRNA modification in E. coli. While transcriptional regulation of MiaA is well characterized, there is no information on the MiaA post-transcriptional regulation. The aim of this study is to characterize the post-transcriptional regulation of the MiaA gene in E. coli. METHODS/STUDY POPULATION: To characterize the post-transcriptional regulation of miaA, we executed a targeted genetic screen of an E. coli small RNA library on a miaA-lacZ translational reporter fusion strain to identify small RNAs (sRNAs) that modulate MiaA translation or transcription termination. We also measured MiaA mRNA levels and miaA-lacZ activity in the absence or over-expression of candidate sRNA regulators of MiaA. We also measured MiaA mRNA levels in the absence of RNaseE and PNPase, two enzymes involved in mRNA turnover. Finally, we measured the ability of purified recombinant CsrA to bind to the MiaA mRNA transcript in vitro. RESULTS/ANTICIPATED RESULTS: We identified the carbon sensing sRNA CsrB and its cognate protein interaction partner CsrA, as potential post-transcriptional regulators of MiaA. Over-expression of CsrB fully repressed miaA-lacZ activity and MiaA mRNA levels. The absence of CsrA resulted in a defective miaA-lacZ activity and a 10-fold decrease in MiaA mRNA levels. We also identified an increase in the MiaA mRNA half-life particularly in the absence of RNaseE. Our results demonstrate an additional layer of regulation for the miaA operon by the CsrA/CsrB protein-sRNA system. DISCUSSION/SIGNIFICANCE: MiaA is a highly conserved bacterial protein. Our data may represent phenomena in an array of bacteria that could be targeted by novel antibiotics. The human MiaA homologue, TRIT1, plays a role in mitochondrial disorders. We anticipate that information garnered from MiaA studies will elucidate TRIT1 function and its role in mitochondrial disorders.

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Gudapaty, Seshagirirao, Kazushi Suzuki, Xin Wang, Paul Babitzke, and Tony Romeo. "Regulatory Interactions of Csr Components: the RNA Binding Protein CsrA Activates csrB Transcription in Escherichia coli." Journal of Bacteriology 184, no. 3 (February 1, 2002): 871. http://dx.doi.org/10.1128/jb.184.3.871-871.2002.

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Federle, Michael J., Kevin S. McIver, and June R. Scott. "A Response Regulator That Represses Transcription of Several Virulence Operons in the Group A Streptococcus." Journal of Bacteriology 181, no. 12 (June 15, 1999): 3649–57. http://dx.doi.org/10.1128/jb.181.12.3649-3657.1999.

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ABSTRACT A search for homologs of the Bacillus subtilis PhoP response regulator in the group A streptococcus (GAS) genome revealed three good candidates. Inactivation of one of these, recently identified as csrR (J. C. Levin and M. R. Wessels, Mol. Microbiol. 30:209–219, 1998), caused the strain to produce mucoid colonies and to increase transcription ofhasA, the first gene in the operon for capsule synthesis. We report here that a nonpolar insertion in this gene also increased transcription of ska (encoding streptokinase),sagA (streptolysin S), and speMF (mitogenic factor) but did not affect transcription of slo(streptolysin O), mga (multiple gene regulator of GAS),emm (M protein), scpA (complement C5a peptidase), or speB or speC (pyrogenic exotoxins B and C). The amounts of streptokinase, streptolysin S, and capsule paralleled the levels of transcription of their genes in all cases. Because CsrR represses genes unrelated to those for capsule synthesis, and because CsrA-CsrB is a global regulatory system inEscherichia coli whose mechanism is unrelated to that of these genes in GAS, the locus has been renamed covR, for “control of virulence genes” in GAS. Transcription of thecovR operon was also increased in the nonpolar insertion mutant, indicating that CovR represses its own synthesis as well. All phenotypes of the covR nonpolar insertion mutant were complemented by the covR gene on a plasmid. CovR acts on operons expressed both in exponential and in stationary phase, demonstrating that the CovR-CovS pathway is separate from growth phase-dependent regulation in GAS. Therefore, CovR is the first multiple-gene repressor of virulence factors described for this important human pathogen.

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Vakulskas, Christopher A., Yuanyuan Leng, Hazuki Abe, Takumi Amaki, Akihiro Okayama, Paul Babitzke, Kazushi Suzuki, and Tony Romeo. "Antagonistic control of the turnover pathway for the global regulatory sRNA CsrB by the CsrA and CsrD proteins." Nucleic Acids Research 44, no. 16 (May 27, 2016): 7896–910. http://dx.doi.org/10.1093/nar/gkw484.

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Yakhnin, Helen, Carol S. Baker, Igor Berezin, Michael A. Evangelista, Alisa Rassin, Tony Romeo, and Paul Babitzke. "CsrA Represses Translation of sdiA , Which Encodes the N -Acylhomoserine-l-Lactone Receptor of Escherichia coli, by Binding Exclusively within the Coding Region of sdiA mRNA." Journal of Bacteriology 193, no. 22 (September 9, 2011): 6162–70. http://dx.doi.org/10.1128/jb.05975-11.

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The RNA binding protein CsrA is the central component of a conserved global regulatory system that activates or represses gene expression posttranscriptionally. In every known example of CsrA-mediated translational control, CsrA binds to the 5′ untranslated region of target transcripts, thereby repressing translation initiation and/or altering the stability of the RNA. Furthermore, with few exceptions, repression by CsrA involves binding directly to the Shine-Dalgarno sequence and blocking ribosome binding. sdiA encodes the quorum-sensing receptor for N -acyl- l -homoserine lactone in Escherichia coli . Because sdiA indirectly stimulates transcription of csrB , which encodes a small RNA (sRNA) antagonist of CsrA, we further explored the relationship between sdiA and the Csr system. Primer extension analysis revealed four putative transcription start sites within 85 nucleotides of the sdiA initiation codon. Potential σ 70 -dependent promoters were identified for each of these primer extension products. In addition, two CsrA binding sites were predicted in the initially translated region of sdiA . Expression of chromosomally integrated sdiA ′-′ lacZ translational fusions containing the entire promoter and CsrA binding site regions indicates that CsrA represses sdiA expression. The results from gel shift and footprint studies demonstrate that tight binding of CsrA requires both of these sites. Furthermore, the results from toeprint and in vitro translation experiments indicate that CsrA represses translation of sdiA by directly competing with 30S ribosomal subunit binding. Thus, this represents the first example of CsrA preventing translation by interacting solely within the coding region of an mRNA target.

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Lee, Ye-Rin, Joon-Hyung Kim, Byung-Chul Choi, and Tae-Young Yoo. "The Types of CSR Activities and Firm Performance : Strategic CSR vs. General CSR." Korean Corporation Management Review 27, no. 1 (February 29, 2020): 1–17. http://dx.doi.org/10.21052/kcmr.2020.27.1.01.

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Nam, Ji-Ahn, and Jong-Seo Choi. "The Moderating Effect of CSR Consistency and CEO ability on CSR-CFP Relation." korean management review 51, no. 3 (June 30, 2022): 643–79. http://dx.doi.org/10.17287/kmr.2022.51.3.643.

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Aubee, Joseph I., Kinlyn Williams, Alexandria Adigun, Olufolakemi Olusanya, and Karl M. Thompson. "31547 Regulation and function of the i6A37 tRNA modification." Journal of Clinical and Translational Science 5, s1 (March 2021): 2. http://dx.doi.org/10.1017/cts.2021.407.

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ABSTRACT IMPACT: MiaA has a human homolog known as TRIT1. Mutations in TRIT1 have been associated with rare diseases such as MELAS and MERRF syndromes. These diseases are associated with mitochondrial disfunction.Understanding the mechanisms of bacterial sRNAs, and the miRNAs associated with these diseases could potentially afford the insight into effective cures. OBJECTIVES/GOALS: The aim is to investigate the regulation and function of tRNA isopentyladenine transferase enzyme in Escherichia coli. We aimed to execute screens for the identification of small RNA regulators of MiaA. The study will also investigate if i6A tRNA modification is necessary for the expression of major heat shock and mitochondrial proteins. METHODS/STUDY POPULATION: We constructed a chromosomal miaA-lacZ translational fusion driven by the arabinose responsive PBAD promoter and used it to screen against an Escherichia coli small RNA library. Using CsrB, one of our candidate sRNA regulators from our genetic screen, we measured the steady state levels of MiaA by Northern Blot in a PBAD-miaA2(P2HS)-lacZ translational fusion strain whereby pBR-pLac-csrB, pBR-pLac-csrA and the pBR-pLac vector are over-expressed, and under the control of an IPTG inducible promoter. Additionally, and in the same PBAD-miaA2(P2HS)-lacZ translational fusion strain background, we measured the steady state levels of MiaA in the wild type, csrA:zeo mutant strain, and csrA:zeo pBR-pLac-csrA complementation strain to determine if a combination of the pair would restore the wild-type genotype. RESULTS/ANTICIPATED RESULTS: Upon measuring the effect of small RNAs on miaA expression using quantitative b-galactosidase assays, we saw a 5-fold decrease in the expression of MiaA in the miaA-lacZ translational fusion containing sRNA CsrB, suggesting that this sRNA may play a role in the regulation of post-transcriptional expression of MiaA.From our northern blotting analysis, we observed a 6-fold decrease in MiaA expression in the absence of csrA, suggesting that csrA is essential for MiaA expression. DISCUSSION/SIGNIFICANCE OF FINDINGS: Identifying, mapping and characterizing how MiaA is regulated post-transcriptionally will give us an increased understanding in the maintenance and regulation of the normal function of E.coli to conserve homeostasis and translation fidelity.

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Ahn, Soo-Kyoung. "Comparison of Ideal versus Actual Fashion Corporate Social Responsibility from a Consumer Perspective." Journal of the Korean Society of Clothing and Textiles 37, no. 5 (July 31, 2013): 631–44. http://dx.doi.org/10.5850/jksct.2013.37.5.631.

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Song, Ha-Min, Mi-Ra Baek, and Byung-Jin Park. "Strategic CSR, CSR Authenticity Perception and Purchase Intention." Korean Corporation Management Review 28, no. 1 (February 28, 2021): 113–30. http://dx.doi.org/10.21052/kcmr.2021.28.1.06.

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MA, X., X. H. CAI, X. L. ZHU, S. F. ZHANG, L. J. MENG, D. C. ZHANG, X. D. YANG, et al. "ATOMIC PHYSICS RESEARCHES AT COOLER STORAGE RING IN LANZHOU." International Journal of Modern Physics E 18, no. 02 (February 2009): 373–80. http://dx.doi.org/10.1142/s0218301309012410.

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The commissioning of the cooler storage rings (CSR) was successful, and the facility provides new possibilities for atomic physics with highly charged ions. Bare carbon, argon ions, were successfully stored in the main ring CSRm, cooled by cold electron beam, and accelerated up to 1 GeV/u. Heavier ions as Xe 44+ and Kr 28+ were also successfully stored in the CSRs. Both of the rings are equipped with new generation of electron coolers which can provide different electron beam density distributions. Electron-ion interactions, high precision X-ray spectroscopy, complete kinematical measurements for relativistic ion-atom collisions will be performed at CSRs. Laser cooling of heavy ions are planned as well. The physics programs and the present status will be summarized.

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XIAO, G. Q., J. W. XIA, Y. J. YUAN, R. S. MAO, J. H. ZHENG, X. L. TU, M. WANG, W. X. HUANG, H. S. XU, and W. L. ZHAN. "OVERVIEW ON THE HIRFL-CSR FACILITY." International Journal of Modern Physics E 18, no. 02 (February 2009): 405–10. http://dx.doi.org/10.1142/s0218301309012446.

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The status of the HIRFL (Heavy Ion Facility in Lanzhou) – Cooler Storage Ring (CSR) at the IMP is reported. The main physics goals at the HIRFL-CSR are the researches on nuclear structure and decay property, EOS of nuclear matter, hadron physics, highly charged atomic physics, high energy density physics, nuclear astrophysics, and applications for cancer therapy, space industries, materials and biology sciences. The HIRFL-CSR is the first ion cooler-storage-ring system in China, which consists of a main ring (CSRm), an experimental ring (CSRe) and a radioactive beam line (RIBLL2). The two existing cyclotrons SFC ( K = 70) and SSC ( K = 450) are used as its injectors. The 7 MeV/u 12 C 6+ ions were stored successfully in CSRm with the stripping injection in January 2006. After that, realized were the accelerations of 12 C 6+, 36 Ar 18+, 78 Kr 28+ and 129 Xe 27+ ions with energies of 1 GeV/u, 1 GeV/u, 450 MeV/u and 235 MeV/u, respectively, including accumulation, electron cooling and acceleration. In 2008, the first two isochronous mass measurement experiments with the primary beams of 36 Ar 18+ and 78 Kr 28+ were performed at CSRe with the Δp/p ~ 10-5.

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Heath, Andrew, Victor J. DiRita, Neil L. Barg, and N. Cary Engleberg. "A Two-Component Regulatory System, CsrR-CsrS, Represses Expression of Three Streptococcus pyogenesVirulence Factors, Hyaluronic Acid Capsule, Streptolysin S, and Pyrogenic Exotoxin B." Infection and Immunity 67, no. 10 (October 1, 1999): 5298–305. http://dx.doi.org/10.1128/iai.67.10.5298-5305.1999.

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ABSTRACT Certain Tn916 insertions in the chromosome of an M1-type, nonmucoid Streptococcus pyogenes isolate (MGAS166) were previously shown to result in stable mucoidy with increased expression of the capsular synthetic genes. The transposon insertions in these strains are directly upstream of an apparent operon encoding a two-component regulatory system, designated csrR-csrS. Compared with MGAS166, these mucoid mutants are more hemolytic and cause significantly more tissue damage in a murine model of skin infection. To extend these observations, we constructed an in-frame deletion in the gene encoding the response regulator, csrR, and we evaluated the expression of other known S. pyogenesvirulence factors. We discovered that csrR mutants have enhanced transcription of sagA, a gene associated with streptolysin S (SLS) and speB, the gene encoding pyrogenic exotoxin B (SpeB). The mutants also express substantially higher SLS activity and SpeB antigen in late-exponential-phase cultures. There is no change in expression of emm, scpA,sic, or cpa (genes encoding other S. pyogenes virulence factors). CsrR− strains but not the wild-type parental strain produce necrotizing lesions in a mouse model of subcutaneous infection. A double mutant with deletions in bothcsrR and the capsular synthesis genes caused fewer and smaller necrotic skin lesions than the csrR mutants. However, this nonmucoid csrR strain was more likely than the wild type to yield necrotic lesions, suggesting that mucoidy contributes to virulence in this model of infection but that there are other csrR-regulated factors involved in the production of necrotic lesions.

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Suzuki, K. "Identification of a novel regulatory protein (CsrD) that targets the global regulatory RNAs CsrB and CsrC for degradation by RNase E." Genes & Development 20, no. 18 (September 15, 2006): 2605–17. http://dx.doi.org/10.1101/gad.1461606.

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Bachman, Michael A., and Michele S. Swanson. "The LetE Protein Enhances Expression of Multiple LetA/LetS-Dependent Transmission Traits by Legionella pneumophila." Infection and Immunity 72, no. 6 (June 2004): 3284–93. http://dx.doi.org/10.1128/iai.72.6.3284-3293.2004.

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ABSTRACT Legionella pneumophila colonizes freshwater amoebae and can also replicate within alveolar macrophages. When their nutrient supply is exhausted, replicating bacteria become cytotoxic, motile, and infectious, which is thought to promote transmission to a new amoeba. The differentiation of L. pneumophila is coordinated by the sigma factors RpoS and FliA and the two-component regulator LetA/LetS and is enhanced by the letE locus. Here we demonstrate that letE promotes motility by increasing expression of the flagellin gene flaA but has little impact on the transcription of fliA, the flagellar sigma factor gene. In addition to promoting motility, letE induces the characteristic shape, pigment, and heat resistance of stationary-phase L. pneumophila. To gain insight into how letE promotes the expression of the transmission phenotype, we designed molecular genetic experiments to discriminate between the following three models: letE mutations are polar on milX; letE encodes a small novel protein; or, by analogy to csrB, letE encodes a regulatory RNA that sequesters CsrA to relieve repression. We report that letE encodes an activator protein, as it does not complement an Escherichia coli csrB mutant, it directs the synthesis of an ∼12-kDa polypeptide, and a letE nonsense mutation eliminates function. A monocistronic letE RNA is abundant during the exponential phase, and its decay during the stationary phase requires RpoS and LetA/LetS. We also discuss how the LetE protein may interact with LetA/LetS and CsrA to enhance L. pneumophila differentiation to a transmissible form.

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Brauweiler, Christian, and Aida Yerimpasheva. "CSR and CSRR in Kazakhstan: state and prospects." Prace Naukowe Uniwersytetu Ekonomicznego we Wrocławiu 63, no. 5 (2019): 105–22. http://dx.doi.org/10.15611/pn.2019.5.09.

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Mondragón, Verónica, Bernardo Franco, Kristina Jonas, Kazushi Suzuki, Tony Romeo, Öjar Melefors, and Dimitris Georgellis. "pH-Dependent Activation of the BarA-UvrY Two-Component System in Escherichia coli." Journal of Bacteriology 188, no. 23 (September 15, 2006): 8303–6. http://dx.doi.org/10.1128/jb.01052-06.

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ABSTRACT The barA and uvrY genes of Escherichia coli encode a two-component sensor kinase and a response regulator, respectively. Although this system plays a major role in the regulation of central carbon metabolism, motility, and biofilm formation by controlling the expression of the CsrB and CsrC noncoding RNAs, the environmental conditions and the physiological signal(s) to which it responds remain obscure. In this study, we explored the effect of external pH on the activity of BarA/UvrY. Our results indicate that a pH lower than 5.5 provides an environment that does not allow activation of the BarA/UvrY signaling pathway.

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Pérez-Morales, Deyanira, Jessica Nava-Galeana, Roberto Rosales-Reyes, Paige Teehan, Helen Yakhnin, Erika I. Melchy-Pérez, Yvonne Rosenstein, Miguel A. De la Cruz, Paul Babitzke, and Víctor H. Bustamante. "An incoherent feedforward loop formed by SirA/BarA, HilE and HilD is involved in controlling the growth cost of virulence factor expression by Salmonella Typhimurium." PLOS Pathogens 17, no. 5 (May 28, 2021): e1009630. http://dx.doi.org/10.1371/journal.ppat.1009630.

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An intricate regulatory network controls the expression of Salmonella virulence genes. The transcriptional regulator HilD plays a central role in this network by controlling the expression of tens of genes mainly required for intestinal colonization. Accordingly, the expression/activity of HilD is highly regulated by multiple factors, such as the SirA/BarA two-component system and the Hcp-like protein HilE. SirA/BarA positively regulates translation of hilD mRNA through a regulatory cascade involving the small RNAs CsrB and CsrC, and the RNA-binding protein CsrA, whereas HilE inhibits HilD activity by protein-protein interaction. In this study, we show that SirA/BarA also positively regulates translation of hilE mRNA through the same mentioned regulatory cascade. Thus, our results reveal a paradoxical regulation exerted by SirA/BarA-Csr on HilD, which involves simultaneous opposite effects, direct positive control and indirect negative control through HilE. This kind of regulation is called an incoherent type-1 feedforward loop (I1-FFL), which is a motif present in certain regulatory networks and represents a complex biological problem to decipher. Interestingly, our results, together with those from a previous study, indicate that HilE, the repressor component of the I1-FFL reported here (I1-FFLSirA/BarA-HilE-HilD), is required to reduce the growth cost imposed by the expression of the genes regulated by HilD. Moreover, we and others found that HilE is necessary for successful intestinal colonization by Salmonella. Thus, these findings support that I1-FFLSirA/BarA-HilE-HilD cooperates to control the precise amount and activity of HilD, for an appropriate balance between the growth cost and the virulence benefit generated by the expression of the genes induced by this regulator. I1-FFLSirA/BarA-HilE-HilD represents a complex regulatory I1-FFL that involves multiple regulators acting at distinct levels of gene expression, as well as showing different connections to the rest of the regulatory network governing Salmonella virulence.

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Shiu, A. "An integrated treatment delivery system for CSRS and CSRT and clinical applications." Journal of Applied Clinical Medical Physics 4, no. 4 (2003): 261. http://dx.doi.org/10.1120/1.1602191.

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Shiu, A., B. Parker, J. S. Ye, and J. Lii. "An integrated treatment delivery system for CSRS and CSRT and clinical applications." Journal of Applied Clinical Medical Physics 4, no. 4 (September 2003): 261–73. http://dx.doi.org/10.1120/jacmp.v4i4.2496.

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Hwang, Sungwook, and Jeesun Kim. "CSR Evaluations Based on Contingent Factors." Korean Journal of Advertising and Public Relations 20, no. 4 (October 31, 2018): 543–74. http://dx.doi.org/10.16914/kjapr.2018.20.4.543.

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Lee, Hye-Sun, and Soo-Yeon Kim. "How does Corporate Social Responsibility of Newspaper Companies affect Public Trust in Newspaper Companies and the Press? : Investigating Editorial Responsibility and CSR Program Types." Korean Journal of Journalism & Communication Studies 64, no. 5 (October 31, 2020): 81–117. http://dx.doi.org/10.20879/kjjcs.2020.64.5.003.

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Beom Gyu, Park, and Kim Hyun Jeong. "A Study on the Necessity and Effect of CSR in Medical Institutions - Focusing on Stakeholder’s Accepted Attitudes and recognition of CSR content -." Journal of Image and Cultural Contents 13 (December 31, 2017): 233–72. http://dx.doi.org/10.24174/jicc.2017.12.13.233.

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Jeong, Jae-Hwi. "신흥시장 진출 다국적기업의 내부 CSR 및 외부 CSR이 HRM 성과에 미치는 영향." Journal of CEO and Management Studies 23, no. 1 (April 30, 2020): 105–20. http://dx.doi.org/10.37674/ceoms.23.1.6.

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안재현 and Seog Kyeun Kwun. "시나리오 접근법을 통한 전략적 CSR과 자선적 CSR의 인지적 해석이 조직매력도와 입사제안 수용의도에 미치는 영향." Korean Journal of Business Ethics 19, no. 2 (December 2019): 29–62. http://dx.doi.org/10.34273/kjbe.2020.19.2.002.

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Gryllos, I., J. C. Levin, and M. R. Wessels. "The CsrR/CsrS two-component system of group A Streptococcus responds to environmental Mg2+." Proceedings of the National Academy of Sciences 100, no. 7 (March 19, 2003): 4227–32. http://dx.doi.org/10.1073/pnas.0636231100.

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Soppe, Aloy, Marc Schauten, Jurjen Soppe, and Uzay Kaymak. "Corporate Social Responsibility Reputation (CSRR): Do Companies Comply with Their Raised CSR Expectations?" Corporate Reputation Review 14, no. 4 (November 25, 2011): 300–323. http://dx.doi.org/10.1057/crr.2011.21.

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46

Teng, Fang, Ling Wang, Kavindra V. Singh, Barbara E. Murray, and George M. Weinstock. "Involvement of PhoP-PhoS Homologs in Enterococcus faecalis Virulence." Infection and Immunity 70, no. 4 (April 2002): 1991–96. http://dx.doi.org/10.1128/iai.70.4.1991-1996.2002.

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ABSTRACT Eleven PhoP-PhoS homolog pairs were identified by searching the Enterococcus faecalis V583 genome sequence database at The Institute for Genomic Research with the Bacillus subtilis PhoP-PhoS sequences. Each pair appears to be a potential two-component system composed of a response regulator and a sensor kinase. Seven of the homologs were disrupted in E. faecalis strain OG1RF. TX10293, a mutant disrupted in one of these genes (etaR, the first gene of the gene pair designated etaRS), showed delayed killing and a higher 50% lethal dose in a mouse peritonitis model. The predicted EtaR protein sequence showed greatest similarity to LisR of Listeria monocytogenes (77%) and CsrR of Streptococcus pyogenes (70%); EtaS is 53% similar to LisK and 54% similar to CsrS. When grown in vitro, the TX10293 mutant was more sensitive to low pH (pH 3.4) and more resistant to high temperature (55°C) than wild-type OG1RF. In conclusion, many potential two-component systems are identified for E. faecalis, one of which, EtaRS, was shown to be involved in stress response and virulence.

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Nayak, Padmanav. "Influence of antibiotic on feed conversion efficiency of mulberry silkworm (Bombyx mori L.)." Animal Biology 56, no. 1 (2006): 13–22. http://dx.doi.org/10.1163/157075606775904731.

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AbstractThe influence of oral intake of an antibiotic (Norfloxacin®) through mulberry leaf at two concentrations (50 and 100 ppm) on the feed conversion efficiency parameters of silkworm hybrids, viz. bivoltine (CSR2 × CSR4) and crossbreed (BL67 × CSR106), was studied. Feed consumption data showed that the food consumption of antibiotic-treated batches was on par with the control. However, nutritional indices parameters such as digesta, approximate digestibility and reference ratio were significantly higher in the antibiotic-treated batches. Similarly, the nutritional efficiency parameters such as efficiency of ingested food into larvae, cocoon and shell were significantly higher in the antibiotic treated batches. The ingesta required to produce one gram of larva, cocoon and shell were significantly lower in treated batches. Most of the feed conversion efficiency parameters related to digesta, such as efficiency of digested food into larvae, cocoon and shell were not significantly different between the control and the treated batches. The results indicated that higher assimilation and conversion of food was observed in silkworm treated with antibiotic.

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Romeo, Tony. "Global regulation by the small RNA‐binding protein CsrA and the non‐coding RNA molecule CsrB." Molecular Microbiology 29, no. 6 (September 1998): 1321–30. http://dx.doi.org/10.1046/j.1365-2958.1998.01021.x.

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Aula, Rahmiatul, Sumiyati Sumiyati, and Muhammad Umar Mai. "The Effect of Corporate Social Responsibility Disclosure on the Performance of Islamic Banks in Indonesia." Jurnal Manajemen Bisnis 13, no. 1 (March 22, 2022): 93–107. http://dx.doi.org/10.18196/mb.v13i1.12832.

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Research aims: This study intends to inspect the effect of Corporate Social Responsibility Disclosure (CSRD) on performance. CSRD was divided into CSRD-All, CSRD-Economic, CSRD-Environment, and CSRD-Social variables. Performance was proxied by the variables ROA and ROE.Design/Methodology/Approach: The research model was built in path analysis and processed using the Wrap-PLS application.Research findings: The analysis results indicated that CSRD tended to be strongly associated with higher bank performance. It was indicated by a significant positive effect of CSRD-All on ROA and ROE. In addition, it was indicated by the significant positive effect of CSRD-Economic and CSRD-Environment on ROA. This study's results contribute to financial literature, particularly the causal relationship between CSRD and Indonesian Sharia Commercial Banks' performance.Theoretical contribution/ Originality: The study results provide insight and input for the management of Islamic Commercial Banks concerning CSRD activities and performance.Practitioner/Policy implication: The results of this study are supposed to be useful as directions for stakeholders in deciding their investment in Indonesian Sharia Commercial Bank shares.Research limitation/Implication: This research only used CSRD, ROA, and ROE.

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Mukherjee, Sampriti, Reid T. Oshiro, Helen Yakhnin, Paul Babitzke, and Daniel B. Kearns. "FliW antagonizes CsrA RNA binding by a noncompetitive allosteric mechanism." Proceedings of the National Academy of Sciences 113, no. 35 (August 11, 2016): 9870–75. http://dx.doi.org/10.1073/pnas.1602455113.

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Abstract:

CsrA (carbon storage regulator A) is a widely distributed bacterial RNA binding protein that regulates translation initiation and mRNA stability of target transcripts. In γ-proteobacteria, CsrA activity is competitively antagonized by one or more small RNAs (sRNAs) containing multiple CsrA binding sites, but CsrA in bacteria outside the γ-proteobacteria is antagonized by a protein called FliW. Here we show that FliW ofBacillus subtilisdoes not bind to the same residues of CsrA required for RNA binding. Instead, CsrA mutants resistant to FliW antagonism (crw) altered residues of CsrA on an allosteric surface of previously unattributed function. Somecrwmutants abolished CsrA–FliW binding, but others did not, suggesting that FliW and RNA interaction is not mutually exclusive. We conclude that FliW inhibits CsrA by a noncompetitive mechanism that differs dramatically from the well-established sRNA inhibitors. FliW is highly conserved with CsrA in bacteria, appears to be the ancestral form of CsrA regulation, and represents a widespread noncompetitive mechanism of CsrA control.

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Journal articles on the topic 'CSRK'

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