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These results demonstrate the establishment of an inducible expression system in cells that can be preserved in the dry state and highlight a possible application to the production of large and complex proteins.Many bacteria possess multiple chemosensory pathways that are composed of homologous signaling proteins. These pathways appear to be functionally insulated from each other, but little information is available on the corresponding molecular basis. We report here a novel mechanism that contributes to pathway insulation. We show that, of the four CheB paralogs of Pseudomonas aeruginosa PAO1, only CheB2 recognizes a pentapeptide at the C-terminal extension of the McpB (Aer2) chemoreceptor (KD = 93 µM). McpB is the sole chemoreceptor that stimulates the Che2 pathway, and CheB2 is the methylesterase of this pathway. Pectobacterium atrosepticum SCRI1043 has a single CheB, CheB_Pec, and 19 of its 36 chemoreceptors contain a C-terminal pentapeptide. The deletion of cheB_Pec abolished chemotaxis, but, surprisingly, none of the pentapeptides bound to CheB_Pec. To determine the corresponding structural basis, we solved the 3D structure of CheB_Pec. Its structure aligned well with that of the pentapeptide-dependent enzyme from Salmonella enterica. However, no electron density was observed in the CheB_Pec region corresponding to the pentapeptide-binding site in the Escherichia coli CheB. We hypothesize that this structural disorder is associated with the failure to bind pentapeptides. Combined data show that CheB methylesterases can be divided into pentapeptide-dependent and independent enzymes.The aim of this study is to investigate on the compression performance of cellular Polylactic Acid (PLA) manufacturing while using Fused Deposition Modelling. Computer Aided Design (CAD) models of cellular structures are designed using the sequential addition of spherical voids with porosity content varying from 10% to 60%. The three-dimensional (3D) microstructures of cellular PLA are characterised using X-ray micro-tomography to retrieve the correlation between the process-induced defects and the cellular geometrical properties. Mechanical testing is performed under severe compression conditions allowing for the reduction in sample height up to 80%. selleck compound Finite element computation that is based on real microstructures is used in order to evaluate the effect of defects on the compression performance. The results show a significant drop of the process-induced defects thanks to the use of small layer thickness. Both mechanical anisotropy and performance loss are reduced due to vanishing process-induced defects more significantly when the amount of intended porosities is large. The compression behaviour of 3D printed PLA cellular structures is then found to be only guided by the amount and distribution of the intended porosity.Delia antiqua, Delia platura and Delia florilega are three root maggot species commonly considered pests in Eastern Canadian onions. The onion maggot, D. antiqua, is considered the primary root maggot pest in onion but it remains unclear whether the other two species are also causing damage. In order to develop updated management strategies for root maggot, we tested adult oviposition and feeding preference by Delia larvae on four growth stages of onion using bioassays and we determined the Delia species composition across the four major onion growing regions in eastern Canada. Delia species oviposit readily on onion at the 5-7 true leaf growth stage but damage on onions is not statistically different between Delia species in our zero-inflated models. The four eastern Canadian onion growing regions have different proportions of Delia species. Southern Ontario and Quebec were the only two regions where Delia antiqua was collected. The highest average numbers of Delia spp. were caught in Quebec and Nova Scotia. Our study shows that timing is important in implementation of management strategies for root maggot in Eastern Canadian onions.Antibiotic resistance is an unprecedented threat to modern medicine. The analysis of volatile organic compounds (VOCs) from bacteria potentially offers a rapid way to determine antibiotic susceptibility in bacteria. This study aimed to find the optimal conditions to obtain the maximum number of VOCs detected which next allowed the assessment of differences in VOC profiles between susceptible and resistant isolates of Escherichia coli causing urinary tract infections. The analysis of VOCs in the headspace above the bacterial cultures allowed the distinguishing of resistant and susceptible bacteria based on the abundance of six VOCs with 85.7% overall accuracy. The results of this preliminary study are promising, and with development could lead to a practical, faster diagnostic method for use in routine microbiology.Histone deacetylases (HDACs) play important roles in transcriptional regulation in eukaryotic cells. Class I deacetylase HDAC1/2 often associates with repressor complexes, such as Sin3 (Switch Independent 3), NuRD (Nucleosome remodeling and deacetylase) and CoREST (Corepressor of RE1 silencing transcription factor) complexes. It has been shown that HDAC1 interacts with and modulates all essential transcription factors for erythropoiesis. During erythropoiesis, histone deacetylase activity is dramatically reduced. Consistently, inhibition of HDAC activity promotes erythroid differentiation. The reduction of HDAC activity not only results in the activation of transcription activators such as GATA-1 (GATA-binding factor 1), TAL1 (TAL BHLH Transcription Factor 1) and KLF1 (Krüpple-like factor 1), but also represses transcription repressors such as PU.1 (Putative oncogene Spi-1). The reduction of histone deacetylase activity is mainly through HDAC1 acetylation that attenuates HDAC1 activity and trans-repress HDAC2 activity through dimerization with HDAC1. Therefore, the acetylation of HDAC1 can convert the corepressor complex to an activator complex for gene activation. HDAC1 also can deacetylate non-histone proteins that play a role on erythropoiesis, therefore adds another layer of gene regulation through HDAC1. Clinically, it has been shown HDACi can reactivate fetal globin in adult erythroid cells. This review will cover the up to date research on the role of HDAC1 in modulating key transcription factors for erythropoiesis and its clinical relevance.