Mise au point d'une stratégie de production de récepteurs couplés aux protéines G fonctionnels en quantités compatibles avec des études structurales

MONTPELLIER-BU Médecine UPM (341722108) / SudocMONTPELLIER-BU Médecine (341722104) / SudocSudocFranceF

Overview of the Oldest Existing Set of Substrate-optimized Anaerobic Processes: Digestive Tracts

International audienceOver millions of years, living organisms have explored and optimized the digestion of a wide variety of substrates. Engineers who develop anaerobic digestion processes for waste treatment and energy production can learn much from this accumulated 'experience'. The aim of this work is a survey based on the comparison of 190 digestive tracts (vertebrate and insect) considered as 'reactors' and their anaerobic processes. Within a digestive tract, each organ is modeled as a type of reactor (continuous stirred-tank, such reactors in series, plug-flow or batch) associated with chemical aspects such as pH or enzymes. Based on this analysis, each complete digestion process has been rebuilt and classified in accordance with basic structures which take into account the relative size of the different reactors. The results show that all animal digestive structures can be grouped within four basic types. Size and/or position in the structure of the different reactors (pre/post treatment and anaerobic microbial digestion) are closely correlated to the degradability of the feed (substrate). Major common features are: (i) grinding, (ii) an extreme pH compartment, and (iii) correlation between the size of the microbial compartment and the degradability of the feed. Thus, shared answers found by animals during their evolution can be a source of inspiration for engineers in designing optimal anaerobic processes

Biomimicry in anaerobic digestion of biological sludge

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How to get 500 million years of experience in anaerobic digestion: animal mimicking

We present an original approach which consists to analyse natural innovation in animal digestive tracts in order to improve anaerobic digestion processes. The first step of this approach consists in a large descriptive inventory of animal digestive tracts. Each digestive system can be divided in elementary steps which could be translated in terms of process engineering: cutting and grinding compartments; Continuous Stirred Tank Reactor (CSTR) or Plug Flow Reactor (PFR); chemical, enzymatic or biological reactors;and filtration press. This paper presents only few examples of animal digestive systems among the huge, mainly unknown, diversity of animal digestive systems. Two types of systems are highlighted. Firstly, we discuss on the evolution of the structures in relation to the feeding habit (carnivorous, omnivorous, granivorous, herbivorous) and secondly, the different features selected by animals in order to face the digestion of ligno-cellulosic compounds. Finally, the different elementary units of the studied digestive systems was compared and their role on the process analysed

How animals can help us on anaerobic digestion? The microbial and process engineering points of view

Over the last decade, pre-treatment and even anaerobic co-digestion strategies have emerged in order to make organic matter more accessible. However, these technologies have been reached less than 60% degradation/conversion of organic matter to methane. In comparison, over millions of years, living organisms have explored and optimized the digestion of a wide variety of substrates with high yields (> 70%). The aim of the study is the analysis of natural innovation in animal digestive tracts in order to improve anaerobic digestion processes. The approach consists of a large descriptive inventory of animal digestive tracts. Animals (vertebrates, arthropods, molluscs, etc.) use all types of organic matter as food. Moreover over evolutionary time, organisms become more and more specialized and use only specific type of food (leaves, seed, meat, bones, faeces, etc.). In parallel, the digestive systems evolve to optimize the nutrient recovery. Each animal species domesticates its own microbe consortium and develops its own digestive tract structure. The digestive systems can be seen as a microbial reactor with abiotic pre- and/or post-treatments. When considering their functions, physiological compartments can be imagined as reactors. Thus, continuous stirred-tank reactors, continuous stirred-tank reactors in series, plug-flow reactors, and batch reactors can be used to model the function of these compartments. In this paper, we relate animal size, animal phylogeny and the feeding habit (carnivorous, omnivorous, granivorous, herbivorous) to the type and the position of microbial compartment with respect to the abiotic compartments within the digestive tract. We also relate the role of these parameters on the microbial diversity within the microbial compartment. The results show that (i) the feeding habit determines the type of microbial reactor and its position within the digestive tract; (ii) the phylogeny of the animal determines the type of abiotic pre- and/or post-treatment; (iii) finally, the size of the animal determines the level of diversity of the microbial communities

The multifunctional protein GC1q-R interacts specifically with the i3 loop arginine cluster of the vasopressin V2 receptor

International audienceIn this study, we identified the multifunctional protein GC1q-R as a novel vasopressin V(2) receptor (V(2)R) interacting protein. For this purpose, we have developed a proteomic approach combining pull-down assays using a cyclic peptide mimicking the third intracellular loop of V(2)R as a bait and mass spectrometry analyses of proteins isolated from either rat or human kidney tissues or the HEK 293 cell line. Co-immunoprecipitation of GC1q-R with the c-Myc-tagged h-V(2)R expressed in a HEK cell line confirmed the existence of a specific interaction between GC1q-R and the V(2) receptor. Then, construction of a mutant receptor in i3 loop allowed us to identify the i3 loop arginine cluster of the vasopressin V(2) receptor as the interacting determinant for GC1q-R interaction. Using purified receptor as a bait and recombinant (74-282) GC1q-R, we demonstrated a direct and specific interaction between these two proteins via the arginine cluster