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Amani Briki Karim Kabor Eric Olmos Sabine Bosselaar Fabrice Blanchard Michel Fick Emmanuel Guedon Frantz Fournier Stphane Delaunay 《Engineering in Life Science》2020,20(5-6):205-215
Corynebacterium glutamicum is well known as an important industrial amino acid producer. For a few years, its ability to produce organic acids, under micro‐aerobic or anaerobic conditions was demonstrated. This study is focused on the identification of the culture parameters influencing the organic acids production and, in particular, the succinate production, by this bacterium. Corynebacterium glutamicum 2262, used throughout this study, was a wild‐type strain, which was not genetically designed for the production of succinate. The oxygenation level and the residual glucose concentration appeared as two critical parameters for the organic acids production. The maximal succinate concentration (4.9 g L?1) corresponded to the lower kLa value of 5 h?1. Above 5 h?1, a transient accumulation of the succinate was observed. Interestingly, the stop in the succinate production was concomitant with a lower threshold glucose concentration of 9 g L?1. Taking into account this threshold, a fed‐batch culture was performed to optimize the succinate production with C. glutamicum 2262. The results showed that this wild‐type strain was able to produce 93.6 g L?1 of succinate, which is one of the highest concentration reported in the literature. 相似文献
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Maxime Olmos Mark R. Payne Marie Nevoux Etienne Prvost Grald Chaput Hubert Du Pontavice Jrme Guitton Timothy Sheehan Katherine Mills Etienne Rivot 《Global Change Biology》2020,26(3):1319-1337
A major challenge in understanding the response of populations to climate change is to separate the effects of local drivers acting independently on specific populations, from the effects of global drivers that impact multiple populations simultaneously and thereby synchronize their dynamics. We investigated the environmental drivers and the demographic mechanisms of the widespread decline in marine survival rates of Atlantic salmon (Salmo salar) over the last four decades. We developed a hierarchical Bayesian life cycle model to quantify the spatial synchrony in the marine survival of 13 large groups of populations (called stock units, SU) from two continental stock groups (CSG) in North America (NA) and Southern Europe (SE) over the period 1971–2014. We found strong coherence in the temporal variation in postsmolt marine survival among the 13 SU of NA and SE. A common North Atlantic trend explains 37% of the temporal variability of the survivals for the 13 SU and declines by a factor of 1.8 over the 1971–2014 time series. Synchrony in survival trends is stronger between SU within each CSG. The common trends at the scale of NA and SE capture 60% and 42% of the total variance of temporal variations, respectively. Temporal variations of the postsmolt survival are best explained by the temporal variations of sea surface temperature (SST, negative correlation) and net primary production indices (PP, positive correlation) encountered by salmon in common domains during their marine migration. Specifically, in the Labrador Sea/Grand Banks for populations from NA, 26% and 24% of variance is captured by SST and PP, respectively and in the Norwegian Sea for populations from SE, 21% and 12% of variance is captured by SST and PP, respectively. The findings support the hypothesis of a response of salmon populations to large climate‐induced changes in the North Atlantic simultaneously impacting populations from distant continental habitats. 相似文献
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Lucho Simone Ribeiro do Amaral Marcelo Nogueira Milech Cristini Bianchi Valmor João Almagro Lorena Ferrer María Ángeles Calderón Antonio Asensio Braga Eugenia Jacira Bolacel 《Plant Cell, Tissue and Organ Culture》2021,146(1):171-184
Plant Cell, Tissue and Organ Culture (PCTOC) - Steviol glycosides (SGs) and gibberellins (GAs) share the same molecular basis. However, the coordination of their respective biosynthetic pathways is... 相似文献
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Gogliettino Marta Cocca Ennio Sandomenico Annamaria Gratino Lorena Iaccarino Emanuela Calvanese Luisa Rossi Mosè Palmieri Gianna 《Molecular biology reports》2021,48(2):1505-1519
Molecular Biology Reports - Serine hydrolases play crucial roles in many physiological and pathophysiological processes and a panel of these enzymes are targets of approved drugs. Despite this,... 相似文献
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Mayarling Francisca Troncoso Jafet Ortiz-Quintero Valeria Garrido-Moreno Fernanda Sanhueza-Olivares Alejandra Guerrero-Moncayo Mario Chiong Pablo F. Castro Lorena García Luigi Gabrielli Ramón Corbalán Luis Garrido-Olivares Sergio Lavandero 《生物化学与生物物理学报:疾病的分子基础》2021,1867(9):166170
The vascular cellular adhesion molecule-1 (VCAM-1) is a protein that canonically participates in the adhesion and transmigration of leukocytes to the interstitium during inflammation. VCAM-1 expression, together with soluble VCAM-1 (sVCAM-1) induced by the shedding of VCAM-1 by metalloproteinases, have been proposed as biomarkers in immunological diseases, cancer, autoimmune myocarditis, and as predictors of mortality and morbidity in patients with chronic heart failure (HF), endothelial injury in patients with coronary artery disease, and arrhythmias. This revision aims to discuss the role of sVCAM-1 as a biomarker to predict the occurrence, development, and preservation of cardiovascular disease. 相似文献
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Lorena MartinJaular Nathalie Nevo Julia P Schessner Mercedes Tkach Mabel Jouve Florent Dingli Damarys Loew Kenneth W Witwer Matias Ostrowski Georg H H Borner Clotilde Thry 《The EMBO journal》2021,40(8)
Cells release diverse types of extracellular vesicles (EVs), which transfer complex signals to surrounding cells. Specific markers to distinguish different EVs (e.g. exosomes, ectosomes, enveloped viruses like HIV) are still lacking. We have developed a proteomic profiling approach for characterizing EV subtype composition and applied it to human Jurkat T cells. We generated an interactive database to define groups of proteins with similar profiles, suggesting release in similar EVs. Biochemical validation confirmed the presence of preferred partners of commonly used exosome markers in EVs: CD81/ADAM10/ITGB1, and CD63/syntenin. We then compared EVs from control and HIV‐1‐infected cells. HIV infection altered EV profiles of several cellular proteins, including MOV10 and SPN, which became incorporated into HIV virions, and SERINC3, which was re‐routed to non‐viral EVs in a Nef‐dependent manner. Furthermore, we found that SERINC3 controls the surface composition of EVs. Our workflow provides an unbiased approach for identifying candidate markers and potential regulators of EV subtypes. It can be widely applied to in vitro experimental systems for investigating physiological or pathological modifications of EV release. 相似文献
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Priscilla Cristine Passoni Silva Oscar Oliveira Brasil Paula Lorena Grangeira Souto Nathalia Hack Moreira Joseane Padilha da Silva Bianca Damiani Marques Silva Alexandre Floriani Ramos 《Animal Reproduction》2021,18(1)
The aim of this study was to use estrus synchronization protocols to favor fixed-time artificial insemination and consequently fixed-time embryo collection, and increase embryo production using eCG, in gits. In a cross over design, nine Piau breed gilts were subjected to 18 days of oral progesterone; P4 group did not receive any further; GnRH group received 25µg of GnRH 104 hours after the final application of P4; and eCG+GnRH group received 1000IU of eCG 24 hours after the final P4 in addition to GnRH for subsequent embryo collection, that was performed six days after first AI, by laparotomy. Artificial insemination was performed after 12 and 24 hours of estrus in P4 group, and 128 and 144 hours in GnRH and eCG+GnRH groups. The number of CL (8.6±3.9; 8.3±2.1; 26.7±15.0) and anovulatory follicles (4.3±3.7; 3.9±3.9; 17.2±9.5) was higher in the eCG+GnRH gilts (P<0.05). However, the use of 1000 IU of eCG reduced (P<0.05) the number of total structures (5.2±3.6; 5.1±3.1; 1.7±2.7), viable embryos (5.0±3.5; 4.8±3.3; 0.4±0.7), freezable embryos (3.6±3.4; 3.3±3.8; 0.1±0.3) and recovery rate (63.7±38.9; 58.6±24.7; 5.38±9.5). P4 and GnRH protocols were effective in the production and recovery of embryos. However, the use of 1000 IU of eCG, 24 hours after P4, was not effective in promoting the production of embryos, although the animals had superovulated. 相似文献
20.
Lilia G Noriega Zesergio Melo Renuga D Rajaram Adriana Mercado Armando R Tovar Laura A VelazquezVillegas María CastaedaBueno Yazmín ReyesLpez Dongryeol Ryu Lorena RojasVega German MagaaAvila Adriana M LpezBarradas Mariana SnchezHernndez Anne Debonneville Alain Doucet Lydie Cheval Nimbe Torres Johan Auwerx Olivier Staub Gerardo Gamba 《EMBO reports》2021,22(5)