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1.
mSphere ; 6(3): e0026421, 2021 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-34106752

RESUMEN

Efficient horizontal gene transfer of the conjugative plasmid pCF10 from Enterococcus faecalis depends on the expression of its type 4 secretion system (T4SS) genes, controlled by the PQ promoter. Transcription from the PQ promoter is tightly regulated, partially to limit cell toxicity caused by overproduction of PrgB, a T4SS adhesin. PrgU plays an important role in regulating this toxicity by decreasing PrgB levels. PrgU has an RNA-binding fold, prompting us to test whether PrgU exerts its regulatory control through binding of prgQ transcripts. We used a combination of in vivo methods to quantify PrgU effects on prgQ transcripts at both single-cell and population levels. PrgU function requires a specific RNA sequence within an intergenic region (IGR) about 400 bp downstream of PQ. PrgU interaction with the IGR reduces levels of downstream transcripts. Single-cell expression analysis showed that cells expressing prgU decreased transcript levels more rapidly than isogenic prgU-minus cells. PrgU bound RNA in vitro without sequence specificity, suggesting that PrgU requires a specific RNA structure or one or more host factors for selective binding in vivo. PrgU binding to its IGR target might recruit RNase(s) for targeted degradation of downstream transcripts or reduce elongation of nascent transcripts beyond the IGR. IMPORTANCE Bacteria utilize type 4 secretion systems (T4SS) to efficiently transfer DNA between donor and recipient cells, thereby spreading genes encoding antibiotic resistance as well as various virulence factors. Regulation of expression of the T4SS proteins and surface adhesins in Gram-positive bacteria is crucial, as some of these are highly toxic to the cell. The significance of our research lies in identifying the novel mechanism by which PrgU performs its delicate fine-tuning of the expression levels. As prgU orthologs are present in various conjugative plasmids and transposons, our results are likely relevant to understanding of diverse clinically important transfer systems.


Asunto(s)
Proteínas Bacterianas/genética , Enterococcus faecalis/genética , Regulación Bacteriana de la Expresión Génica , Feromonas/metabolismo , Plásmidos/genética , ADN Bacteriano/genética , Operón , Feromonas/genética , Sistemas de Secreción Tipo IV/genética , Sistemas de Secreción Tipo IV/metabolismo
2.
J Bacteriol ; 202(8)2020 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-32041799

RESUMEN

For high-frequency transfer of pCF10 between E. faecalis cells, induced expression of the pCF10 genes encoding conjugative machinery from the prgQ operon is required. This process is initiated by the cCF10 (C) inducer peptide produced by potential recipient cells. The expression timing of prgB, an "early" gene just downstream of the inducible promoter, has been studied extensively in single cells. However, several previous studies suggest that only 1 to 10% of donors induced for early prgQ gene expression actually transfer plasmids to recipients, even at a very high recipient population density. One possible explanation for this is that only a minority of pheromone-induced donors actually transcribe the entire prgQ operon. Such cells would not be able to functionally conjugate but might play another role in the group behavior of donors. Here, we sought to (i) simultaneously assess the presence of RNAs produced from the proximal (early induced transcripts [early Q]) and distal (late Q) portions of the prgQ operon in individual cells, (ii) investigate the prevalence of heterogeneity in induced transcript length, and (iii) evaluate the temporality of induced transcript expression. Using fluorescent in situ hybridization chain reaction (HCR) transcript labeling and single-cell microscopic analysis, we observed that most cells expressing early transcripts (QL, prgB, and prgA) also expressed late transcripts (prgJ, pcfC, and pcfG). These data support the conclusion that, after induction is initiated, transcription likely extends through the end of the conjugation machinery operon for most, if not all, induced cells.IMPORTANCE In Enterococcus faecalis, conjugative plasmids like pCF10 often carry antibiotic resistance genes. With antibiotic treatment, bacteria benefit from plasmid carriage; however, without antibiotic treatment, plasmid gene expression may have a fitness cost. Transfer of pCF10 is mediated by cell-to-cell signaling, which activates the expression of conjugation genes and leads to efficient plasmid transfer. Yet, not all donor cells in induced populations transfer the plasmid. We examined whether induced cells might not be able to functionally conjugate due to premature induced transcript termination. Single-cell analysis showed that most induced cells do, in fact, express all of the genes required for conjugation, suggesting that premature transcription termination within the prgQ operon does not account for failure of induced donor cell gene transfer.


Asunto(s)
Conjugación Genética , Enterococcus faecalis/citología , Enterococcus faecalis/genética , Operón , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Enterococcus faecalis/metabolismo , Regulación Bacteriana de la Expresión Génica , Oligopéptidos/genética , Oligopéptidos/metabolismo , Feromonas/genética , Feromonas/metabolismo , Regiones Promotoras Genéticas , Análisis de la Célula Individual
3.
Mol Microbiol ; 112(3): 1010-1023, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31265752

RESUMEN

Enterococcal pheromone responsive conjugative plasmids like pCF10 promote horizontal spread of antibiotic resistance genes following induction of plasmid-containing cells by potential recipients. Transcription of conjugation genes from promoter PQ is inhibited by the master regulator PrgX, further repressed when PrgX is in complex with the inhibitory I peptide, and allowed when PrgX is in complex with the C inducing peptide. Single-cell analysis has shown that heterogeneity in the pheromone response is prevalent. Here, we systematically varied levels of regulatory molecules to better understand why some individual cells have increased propensity for induction. In this study, PrgX was confirmed to repress PQ in the absence of exogenous peptides in vivo, but cells with increased levels of PrgX were shown to be more prone to induction. Further, ablation of endogenous I reduced PrgX levels, resulting in reduced basal repression and loss of inducibility. Reduction of both endogenous peptides by washing increased the inducibility of cells. Together, these results show that endogenous PrgX, C, and I levels can impact the induction potential of a cell and establish the importance of basal I for regulation. These results also suggest that PrgX/C complexes may directly activate prgQ transcription, contrary to a long-standing working model.


Asunto(s)
Proteínas Bacterianas/metabolismo , Conjugación Genética , Enterococcus faecalis/metabolismo , Regulación Bacteriana de la Expresión Génica , Oligopéptidos/metabolismo , Feromonas/metabolismo , Proteínas Bacterianas/genética , Enterococcus faecalis/genética , Oligopéptidos/genética , Operón , Feromonas/genética , Regiones Promotoras Genéticas , Señales de Clasificación de Proteína/genética
4.
Qual Health Res ; 28(1): 145-158, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29094641

RESUMEN

In this article, we examine how race and gender shape nurses' emotion practice. Based on audio diaries collected from 48 nurses within two Midwestern hospital systems in the United States, we illustrate the disproportionate emotional labor that emerges among women nurses of color in the white institutional space of American health care. In this environment, women of color experience an emotional double shift as a result of negotiating patient, coworker, and supervisor interactions. In confronting racist encounters, nurses of color in our sample experience additional job-related stress, must perform disproportionate amounts of emotional labor, and experience depleted emotional resources that negatively influence patient care. Methodologically, the study extends prior research by using audio diaries collected from a racially diverse sample to capture emotion as a situationally emergent and complex feature of nursing practice. We also extend research on nursing by tracing both the sources and consequences of unequal emotion practices for nurse well-being and patient care.


Asunto(s)
Emociones , Relaciones Enfermero-Paciente , Personal de Enfermería en Hospital/psicología , Grupos Raciales/psicología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medio Oeste de Estados Unidos , Racismo/psicología , Factores Sexuales , Encuestas y Cuestionarios
5.
Soc Sci Med ; 167: 99-106, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27619753

RESUMEN

For nurses and other caregivers there is a strong emphasis on prosocial forms of motivation, or doing the job because you want to help others, even in formal, institutionalized care settings. This emphasis is based in gendered assumptions that altruistic motivations are the "right" reasons for being a nurse and lead to the best outcomes for workers and patients. Other motivations for pursuing care work, particularly extrinsic motivation, depart from the prosocial model of care and may be indicative of substandard outcomes, but little research has examined variation in care workers' motivations for doing their jobs. In this study, we use survey data collected from 730 acute care hospital nurses working within one health care system in the Midwestern United States to examine whether different sources of motivation for being a nurse are related to nurse job burnout, negative physical symptoms, and turnover intentions. Our findings suggest that nurses who have high intrinsic and extrinsic motivation actually have better perceived health and employment outcomes (i.e., less likely to say that they will leave, lower burnout, fewer negative physical symptoms) than those with high prosocial motivation, who are more likely to report job burnout.


Asunto(s)
Empatía , Trabajo de Parto/psicología , Motivación , Enfermeras y Enfermeros/psicología , Adulto , Agotamiento Profesional/etiología , Agotamiento Profesional/psicología , Empleo/normas , Femenino , Humanos , Satisfacción en el Trabajo , Masculino , Persona de Mediana Edad , Medio Oeste de Estados Unidos , Embarazo , Encuestas y Cuestionarios
6.
Appl Nurs Res ; 31: 121-5, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27397829

RESUMEN

PURPOSE: In the current healthcare context, large health care organizations may increasingly emphasize profit, biomedicine, efficiency, and customer service in the delivery of care. This orientation toward nursing work by large organizations may be perceived by nurses as incompatible with professional caring. METHODS: Ordinary Least Squares regression was used to explore the impact of person-organization fit (i.e., value congruence between self and employing organization) on nurses' general job satisfaction and quality of patient care (n=753). RESULTS: Nurses' perceived person-organization fit is a significant predictor of general job satisfaction and quality of patient care. CONCLUSION: The implications of our findings are discussed and recommendations for nursing leaders and future research are made.


Asunto(s)
Satisfacción en el Trabajo , Personal de Enfermería en Hospital/psicología , Calidad de la Atención de Salud , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Res Nurs Health ; 36(6): 567-81, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24122833

RESUMEN

Few researchers have examined how the components of the Practice Environment Scale of the Nursing Work Index (PES-NWI) relate to nurses' well-being at multiple organizational levels. The objective of the study was to perform a multilevel assessment of the relationships of the PES-NWI subscales with three nurse outcomes: job satisfaction, emotional exhaustion, and turnover intentions. Additionally, we tested the multilevel factor structure of the PES-NWI. In a sample of 699 full-time registered nurses in 79 units and 9 branches of a hospital system, relationships of the NWI with nurse outcomes were fairly consistent across levels of analysis. However, subscales contributed differently to the three outcomes, demonstrating the complexity of environmental influences on nurses' work experience.


Asunto(s)
Ambiente de Instituciones de Salud/organización & administración , Satisfacción en el Trabajo , Personal de Enfermería en Hospital/organización & administración , Evaluación de Resultado en la Atención de Salud , Encuestas y Cuestionarios/normas , Carga de Trabajo/estadística & datos numéricos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Metodológica en Enfermería , Calidad de la Atención de Salud , Proyectos de Investigación , Lugar de Trabajo/organización & administración , Lugar de Trabajo/estadística & datos numéricos
8.
West J Nurs Res ; 35(8): 970-85, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23552392

RESUMEN

Little is known about how exclusionary practices (i.e., ignored, ostracized) by managers differ across demographics and influence nursing outcomes. This study examines whether managerial exclusion varies by generation, race, and gender, and the extent to which these variables, in turn, relate to turnover intention and perceived patient care among a sample of 747 nurses working in hospitals in a midwestern health system. Exclusion did not differ across most demographic groups, though men reported less exclusion than women. Younger nurses of the Millennial generation, those feeling excluded, and those with fewer years of experience reported lower quality patient care. Managerial exclusion, being a nurse of color, and less experience were associated with stronger intentions to leave. Nursing leaders should attend to factors that may contribute to racial minorities seeking other jobs, diminish younger nurses' ability to provide high-quality care, and minimize practices that might lead nurses to feel excluded.


Asunto(s)
Personal de Enfermería/psicología , Supervisión de Enfermería , Reorganización del Personal , Calidad de la Atención de Salud , Humanos , Medio Oeste de Estados Unidos
9.
J Appl Psychol ; 96(5): 1095-104, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21639600

RESUMEN

Focusing on a sample of nurses, this investigation examined the relationships of daily task accomplishment satisfaction (for direct and indirect care tasks) with changes in positive and negative affect from preshift to postshift. Not accomplishing tasks to one's satisfaction was conceptualized as a daily workplace stressor that should increase daily negative affect and decrease daily positive affect from preshift to postshift. Further, because of the greater centrality of direct care nursing tasks to nursing work role identities (relative to indirect care tasks), we expected that task accomplishment satisfaction (or lack thereof) for these tasks would have stronger effects on changes in affect than would task accomplishment satisfaction for indirect care tasks. We also examined 2 person-level resources, collegial nurse-physician relations and psychological resilience, as moderators of the relationships among these daily variables, with the expectation that these resources would buffer the harmful effects of low task accomplishment satisfaction on nurse affect. Results supported almost all of the proposed effects, though the cross-level interactions were observed only for the effects of indirect care task accomplishment satisfaction on affect and not for direct care task accomplishment satisfaction on affect.


Asunto(s)
Afecto/fisiología , Satisfacción en el Trabajo , Enfermeras y Enfermeros/psicología , Relaciones Médico-Enfermero , Resiliencia Psicológica , Lugar de Trabajo/psicología , Femenino , Humanos , Masculino , Modelos Psicológicos
10.
J Occup Health Psychol ; 16(2): 170-86, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21244168

RESUMEN

Emotional labor theory has conceptualized emotional display rules as shared norms governing the expression of emotions at work. Using a sample of registered nurses working in different units of a hospital system, we provided the first empirical evidence that display rules can be represented as shared, unit-level beliefs. Additionally, controlling for the influence of dispositional affectivity, individual-level display rule perceptions, and emotion regulation, we found that unit-level display rules are associated with individual-level job satisfaction. We also showed that unit-level display rules relate to burnout indirectly through individual-level display rule perceptions and emotion regulation strategies. Finally, unit-level display rules also interacted with individual-level dispositional affectivity to predict employee use of emotion regulation strategies. We discuss how future research on emotional labor and display rules, particularly in the health care setting, can build on these findings.


Asunto(s)
Emociones , Enfermeras y Enfermeros/psicología , Lugar de Trabajo/psicología , Adulto , Afecto , Agotamiento Profesional/psicología , Femenino , Humanos , Satisfacción en el Trabajo , Masculino , Salud Mental , Cultura Organizacional
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