On the ancestral UDP-glucose pyrophosphorylase activity of GalF from Escherichia coli

In bacteria, UDP-glucose is a central intermediate in carbohydrate metabolism. The enzyme responsible for its synthesis is encoded by the galU gene and its deletion generates cells unable to ferment galactose. In some bacteria, there is a second gene, galF, encoding for a protein with high sequence identity to GalU. However, the role of GalF has been contradictory regarding its catalytic capability and not well understood. In this work we show that GalF derives from a catalytic (UDP-glucose pyrophosphorylase) ancestor, but its activity is very low compared to GalU. We demonstrated that GalF has some residual UDP-glucose pyrophosphorylase activity by in vitro and in vivo experiments in which the phenotype of a galU- strain was reverted by the over-expression of GalF and its mutant. To demonstrate its evolutionary path of "enzyme inactivation" we enhanced the catalysis by mutagenesis and showed the importance of the quaternary structure. This study provides important information to understand the structural and functional evolutionary origin of the protein GalF in enteric bacteria.Fil: Ebrecht, Ana Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentina. Loyola University; Estados UnidosFil: Orlof, Agnieszka M.. Loyola University; Estados UnidosFil: Sasoni, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Figueroa, Carlos Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Iglesias, Alberto Alvaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Ballicora, Miguel A.. Loyola University; Estados Unido

The Coupling of Pain, Anxiety, and Stress

Es gibt zahlreiche neurobiologische, klinische und epidemiologische Belege dafür, dass die Phänomene der Angst- und der Schmerzempfindung eng miteinander interagieren. Beide Systeme gehen mit Stressaktivierungsvorgängen einher, und beide Systeme werden ihrerseits durch Langzeitstress moduliert. Die Koppelung von Schmerz, Angst und Stress erklärt auch die hohe Komorbidität von Schmerz- und Angsterkrankungen. Diese Zusammenhänge sollen auffordern, die individuelle Patientenrealität in ihrer integrativen Gesamtheit zu erfassen, in der sich nozizeptive, affektive und vegetative Symptome oftmals bedingen und verstärken.There is considerable neurobiological, clinical and epidemiological evidence that the systemic phenomena of anxiety and pain closely interact. Both perceptions trigger stress activation processes and are in turn modulated by long-term stress. This overview illustrates the coupling of pain, anxiety and stress with some clinical examples. The relations shown here should help us to gain a holistic view of the individual patient and his/her psychosocial reality, in which nociceptive, affective and vegetative symptoms are often interdependent and mutually reinforcing each other