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The N-acyl-L-homoserine lactone (AHL) quorum sensing regulates virulence in the opportunistic pathogen, Pseudomonas aeruginosa. The LasI and RhlI AHL synthases use acyl carrier protein substrates to synthesize, respectively, the 3-oxododecanoyl-L-homoserine lactone (3-oxoC12-HSL) and butyryl-L-homoserine lactone (C4-HSL) QS signals for this bacterium. Although P. aeruginosa genome contains three open reading frames to encode three acyl carrier proteins, namely the ACP1, ACP2 and ACP3, microarray and gene replacement studies show that only the ACP1 carrier protein is under quorum sensing regulation. In this study, we isotopically enriched one of the acyl carrier proteins, ACP1 from P. aeruginosa and describe the backbone resonance assignments for this protein to delineate the structural and molecular basis of ACP1 recognition in P. aeruginosa AHL quorum sensing signal synthesis.
Asunto(s)
Proteína Transportadora de Acilo , Pseudomonas aeruginosa , Pseudomonas aeruginosa/metabolismo , Proteína Transportadora de Acilo/metabolismo , Resonancia Magnética Nuclear Biomolecular , Percepción de Quorum , Acil-Butirolactonas/metabolismo , Proteínas Bacterianas/metabolismoRESUMEN
Acyl carrier proteins (ACPs) are universally conserved proteins amongst different species and are involved in fatty acid synthesis. Bacteria utilize ACPs as acyl carriers and donors for the synthesis of products such as endotoxins or acyl homoserine lactones (AHLs), which are used in quorum sensing mechanisms. In this study, wehave expressed isotopically labeled holo-ACP from Burkholderia mallei in Escherichia coli to assign 100% of non-proline backbone amide (HN) resonances, 95.5% of aliphatic carbon resonances and 98.6% of aliphatic hydrogen sidechain resonances.
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Proteína Transportadora de Acilo , Burkholderia mallei , Proteína Transportadora de Acilo/metabolismo , Burkholderia mallei/metabolismo , Resonancia Magnética Nuclear Biomolecular , Escherichia coli/metabolismo , Proteínas Bacterianas/metabolismoRESUMEN
Acyl-homoserine lactone synthases make specific AHL quorum sensing signals to aid virulence in Gram-negative bacteria. Here, we use solution NMR spectroscopy to demonstrate that the carrier protein-enzyme interface accurately reveals substrate recognition mechanisms in two quorum signal synthases.
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Proteínas Bacterianas , Proteínas Portadoras , Proteínas Portadoras/metabolismo , Proteínas Bacterianas/metabolismo , Bacterias Gramnegativas/metabolismo , Percepción de Quorum , Virulencia , Acil-Butirolactonas/química , Acil-Butirolactonas/metabolismoRESUMEN
Grant writing is an important skill to develop during graduate school. This article provides an overview of grant writing for graduate students. Specific topics covered include understanding your funding needs, identifying appropriate grant opportunities, analyzing the guidelines for the proposal, planning and time management, understanding the priorities of the funding agency or organization, proposal organization and writing strategies, additional forms and letters of support that may be required, the editing and revising process, and submission of your grant proposal. Courses and workshops are an efficient and effective way to be guided through the grant proposal writing process with a greater potential for positive outcomes. © 2022 Wiley Periodicals LLC.
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Organización de la Financiación , Escritura , Humanos , Instituciones Académicas , EstudiantesRESUMEN
Collagen α1(XI) is a minor fibrillar collagen involved in the critical regulation of collagen fibrils such as nucleation, assembly, and regulation of fibril diameter. The amino propeptide domain of the collagen α1(XI) is retained on the surface of the collagen fibril for an extended period of time and may play a crucial role in the interaction with extracellular matrix glycosaminoglycans and other proteins during the process of fibrillogenesis. Understanding the mechanism of action of this protein will ultimately help us understand the organization and assembly of the extracellular matrix that underlies the structural integrity of connective tissues.
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Background: Pneumonia is a major cause of child mortality among children under 5 years, worldwide. Pneumonia infection may be caused by bacteria, viruses, or fungi in single or in both lungs. According to recent criteria developed by the World Health Organization(WHO) in September (2013), pneumonia can be classified into severe pneumonia, pneumonia and no pneumonia. Most of the deaths occur from severe pneumonia. Methods: Disease management of severe childhood pneumonia requires early identification,prompt referral and the availability of intensive quality care. Under 5 years old children with severe pneumonia should receive day care, with antibiotic treatment, feeding, and supportive care with similar 24-hour hospital treatment. Results: Considering that difficulties, International Centre for Diarrheal Disease Research,Bangladesh (ICDDR, B) initiated Day Care Approach (DCA) model, as an innovative, safe,effective and less expensive alternative to hospital management of severe childhood pneumonia.A 24 months old girl came to the health care center with severe breathing difficulty, cough,history of fever and head nodding. The management described below was continued daily until there was clinical improvement; no fever, no fast breathing, no lower chest wall in drawing, no danger signs, no rales on auscultation, and no hypoxemia. Conclusion: Considering the WHO case management protocol for severe pneumonia, DCA recommends that diagnosis of severe pneumonia should be based primarily on visible clinical parameters. On that basis, severe childhood pneumonia can be successfully managed at daycare clinics including for children with hypoxemia who is required prolong (4-6 hours) oxygen therapy.