Proteomics of <i>Pseudomonas aeruginosa</i> Australian Epidemic Strain 1 (AES-1) Cultured under Conditions Mimicking the Cystic Fibrosis Lung Reveals Increased Iron Acquisition via the Siderophore Pyochelin

<i>Pseudomonas aeruginosa</i> is an opportunistic pathogen that is the major cause of morbidity and mortality in patients with cystic fibrosis (CF). While most CF patients are thought to acquire <i>P. aeruginosa</i> from the environment, person-to-person transmissible strains have been identified in CF clinics worldwide, and the molecular basis for transmissibility remains poorly understood. We undertook a complementary proteomics approach to characterize protein profiles from a transmissible, acute isolate of the Australian epidemic strain 1 (AES-1R), the virulent burns/wound isolate PA14, and the poorly virulent, laboratory-associated strain PAO1 when grown in an artificial medium that mimics the CF lung environment compared to growth in standard laboratory medium. Proteins elevated in abundance in AES-1R included those involved in methionine and <i>S</i>-adenosylmethionine biosynthesis and in the synthesis of phenazines. Proteomic data were validated by measuring culture supernatant levels of the virulence factor pyocyanin, which is the final product of the phenazine pathway. AES-1R and PAO1 released higher extracellular levels of pyocyanin compared to PA14 when grown in conditions that mimic the CF lung. Proteins associated with biosynthesis of the iron-scavenging siderophore pyochelin (PchDEFGH and FptA) were also present at elevated abundance in AES-1R and at much higher levels than in PAO1, whereas they were reduced in PA14. These protein changes resulted phenotypically in increased extracellular iron acquisition potential and, specifically, elevated pyochelin levels in AES-1R culture supernatants as detected by chrome azurol-S assay and fluorometry, respectively. Transcript analysis of pyochelin genes (<i>pchDFG</i> and <i>fptA</i>) showed they were highly expressed during the early stage of growth in artificial sputum medium (18 h) but returned to basal levels following the establishment of microcolony growth (72 h) consistent with that observed in the CF lung. This provides further evidence that iron acquisition by pyochelin may play a role in the early stages of transmissible CF infection associated with AES-1R

Proteomics of <i>Pseudomonas aeruginosa</i> Australian Epidemic Strain 1 (AES-1) Cultured under Conditions Mimicking the Cystic Fibrosis Lung Reveals Increased Iron Acquisition via the Siderophore Pyochelin

<i>Pseudomonas aeruginosa</i> is an opportunistic pathogen that is the major cause of morbidity and mortality in patients with cystic fibrosis (CF). While most CF patients are thought to acquire <i>P. aeruginosa</i> from the environment, person-to-person transmissible strains have been identified in CF clinics worldwide, and the molecular basis for transmissibility remains poorly understood. We undertook a complementary proteomics approach to characterize protein profiles from a transmissible, acute isolate of the Australian epidemic strain 1 (AES-1R), the virulent burns/wound isolate PA14, and the poorly virulent, laboratory-associated strain PAO1 when grown in an artificial medium that mimics the CF lung environment compared to growth in standard laboratory medium. Proteins elevated in abundance in AES-1R included those involved in methionine and <i>S</i>-adenosylmethionine biosynthesis and in the synthesis of phenazines. Proteomic data were validated by measuring culture supernatant levels of the virulence factor pyocyanin, which is the final product of the phenazine pathway. AES-1R and PAO1 released higher extracellular levels of pyocyanin compared to PA14 when grown in conditions that mimic the CF lung. Proteins associated with biosynthesis of the iron-scavenging siderophore pyochelin (PchDEFGH and FptA) were also present at elevated abundance in AES-1R and at much higher levels than in PAO1, whereas they were reduced in PA14. These protein changes resulted phenotypically in increased extracellular iron acquisition potential and, specifically, elevated pyochelin levels in AES-1R culture supernatants as detected by chrome azurol-S assay and fluorometry, respectively. Transcript analysis of pyochelin genes (<i>pchDFG</i> and <i>fptA</i>) showed they were highly expressed during the early stage of growth in artificial sputum medium (18 h) but returned to basal levels following the establishment of microcolony growth (72 h) consistent with that observed in the CF lung. This provides further evidence that iron acquisition by pyochelin may play a role in the early stages of transmissible CF infection associated with AES-1R

Responsibility to Protect (R2P) in French Foreign Policy 2008 - 2013

This Master's thesis deals with the emerging international norm Responsibility to Protect (R2P) in French Foreign Policy between 2008 and 2013. Responsibility to Protect was created in 2001 by the International Commission on Intervention and State Sovereignty and endorsed by the UN World Summit in 2005. It has changed the understanding of state sovereignty in international relations by emphasizing the responsibility component of sovereignty. It gives priority to the security of individuals. France has been an active agenda-setter in the field of human protection norms in the 1980s and 1990s and it has showed a supportive approach towards R2P. The thesis examines whether the conceptualization of R2P in current French foreign policy is coherent with this tradition. The research is based on the concepts of ethical foreign policy and alternative national interest. The analysis of strategic documents setting the priorities of French foreign policy between 2008 and 2013 as well as an examination of the three military interventions based on R2P (Libya, Côte d'Ivoire and Central African Republic) in which France played an active role have shown that in the France's foreign policy is based on moral principles which it upholds in strategic documents. In practice ethical foreign policy also prevails over..