Editorial: Microbial Regulation of Translation

Since the description of the operon model by Jacob and Monod during the late 1950s and early 1960s (Ullmann, 2010), the concept that the reading of genetic information must be a regulated process has been central to our understanding of biology. This is particularly true for microbes, which can adapt to an incredible variety of environments. Based on the research performed since the description of the operon, we have gained a deep understanding of the diverse strategies used by microbes to modulate the transcription of genetic information from DNA to RNA. In contrast, the mechanisms that regulate the translation of messenger RNAs into proteins has received less attention. The technical developments of the last decade now allow us to obtain detailed information on RNA folding (Rouskin et al., 2014; Aw et al., 2016) and modification (Linder et al., 2015; Lorenz et al., 2020) and the speed of translation (Subramaniam et al., 2013; Ingolia, 2014; Dai et al., 2016). This, in turn, allows us to scrutinize the functionality of translation components in vivo, providing unprecedented opportunities to study translation regulation. In this special issue of Frontiers in Genetics, \u27Microbial Regulation of Translation,\u27 we have assembled a series of articles that use diverse experimental approaches to study the regulation of translation in microbes

Effects of exogenous lactase administration on hydrogen breath excretion and intestinal symptoms in patients presenting lactose malabsorption and intolerance

To establish whether supplementation with a standard oral dose of Beta-Galactosidase affects hydrogen breath excretion in patients presenting with lactose malabsorption. METHODS: Ninety-six consecutive patients positive to H2 Lactose Breath Test were enrolled. Mean peak H2 levels, the time to reach the peak H2, the time to reach the cut-off value of 20 ppm, the cumulative breath H2 excretion, the areas under the curve, and a Visual Analogical 10-point Scale for symptoms were calculated. Genotyping of the C/T-13910 variant was carried out. RESULTS: Following the oral administration of Beta-Galactosidase, in 21.88% of the cases, H2 Lactose Breath Test became negative (Group A), while mean peak H2 levels (74.95 ppm versus 7.85), P < 0.0000, in 17.71% (Group B) were still positive, with the H2 level 20 ppm above the baseline, but the peak H2 levels were significantly lower than those observed at the baseline test (186.7 ppm versus 66.64), P < 0.0000, while in 60.41% (Group C) they were still positive with the peak H2 levels similar to those observed at the baseline test (94.43 versus 81.60 ppm). All 96 individuals tested presented the C/C-13910 genotype nonpersistence. CONCLUSIONS: The response to oral administration of Beta-Galactosidase in patients with symptoms of lactose malabsorption presents a significant variability

Anti-BVDV activity evaluation of naphthoimidazole derivatives compared with parental imidazoquinoline compounds.

Background: Pestivirus genus includes animal pathogens which are involved in economic impact for the livestock industry. Among others, Bovine Viral Diarrhoea Virus (BVDV) establish a persistent infection in cattle causing a long list of symptoms and a high mortality rate. In the last decades, we synthesised and reported a certain number of anti-BVDV compounds. Methods: In them, imidazoquinoline derivatives turned out as the most active. Their mechanism of actions has been deeply investigated, BVDV RNA-dependent RNA polymerase (RpRd) resulted as target and the way of binding was predicted in silico through three main H-bond interaction with the target. The prediction could be confirmed by target or ligand mutation. The first approach has already been performed and published confirming the in silico prediction. Results: Here, we present how the ligand chemical modification affects the anti-BVDV activity. The designed compounds were synthesised and tested against BVDV as in silico assay negative control. Conclusion: The antiviral results confirmed the predicted mechanism of action, as the newly synthesised compounds resulted not active in the in vitro BVDV infection inhibitio

Foraminiferal biotopes in a shallow continental shelf environment: Esperance Bay (southwestern Australia)

The Great Australian Bight is a large carbonate cold water environment located on the central and western portions of the southern Australia. Seagrasses (Posidonia sp.) and macroalgae benthic habitats are widely distributed in the shallow water environment of southern Australia, contributing to the carbonate factory. This study investigated the distribution of modern benthic foraminiferal assemblages in the microtidal wave-dominated inner-shelf of Esperance Bay (southwestern Australia), that lies on the western margin of the Great Australian Bight. Benthic foraminifera were taxonomically identified and biotic parameters (species richness, density, Fisher-α index, Shannon–Weaver index, dominance) were calculated. Multivariate analyses (Hierarchical Cluster Analysis, Principal Component Analysis) were performed to understand foraminiferal distribution in the context of environmental conditions. Four main Foraminiferal assemblages have been recognized: (I) a nearshore assemblage of dense seagrass meadow, dominated by Lamellodiscorbis dimidiatus, Elphidium craticulatum, Elphidium crispum, Cibicidoides lobatulus, II) a second assemblage associated with unvegetated seabed (approximately 30 m depth) with Lamellodiscorbis dimidiatus, Elphidium crispum, Quinqueloculina disparilis, III) a third assemblage in the central sector of the bay, characterized by a discontinuous and mixed seagrass-algae coverage with Lamellodiscorbis dimidiatus, Elphidium crispum, Elphidium macellum, Cibicides refulgens, and Quinqueloculina poeyana, and IV) an epiphytic assemblage of transitional zone from the coastline to the upper limit of a mixed seagrass-algae meadow, dominated by Elphidium crispum, Chrysalidinella dimorpha, Planulinoides biconcava, Planoglabratella opercularis, Rugobolivinella elegans. The spatial distribution of the four assemblages appears closely related to sediment texture, seagrass cover and depth, but it is also influenced by the shoreface morphology and the hydrodynamic energy. The understanding of the ecological parameters that influence benthic foraminiferal distribution, composition and assemblage structure within seagrass meadows is useful for paleoecological and paleoenvironmental interpretations

Identificazione di schiume in polipropilene e relazione tra densità e parametri dei modelli

La varietà praticamente infinita di solidi cellulari rende particolarmente ardua la modellazione di questi materiali, per ognuno dei quali è in genere necessaria una specifica identificazione. La ricerca di legami tra i parametri dei modelli e le caratteristiche note della schiuma è utile per ridurre il lavoro di identificazione ed evitare una eccessiva quantità di esperimenti. Prove sperimentali di compressione uniassiale statica su schiume rigide di EPP a cinque densità diverse sono state utilizzate per identificare i modelli di Gibson e Rush. I parametri identificati per il modello di Gibson sono stati confrontati con quelli dati dalle espressioni dello stesso autore in funzione della densità. I parametri identificati per il modello di Rush sono stati studiati per individuare relazioni analitiche simili a quelle di Gibson tra i parametri e la densità

Effects of industrial processing on pesticide multiresidues transfer from raw tomatoes to processed products

Pesticides are broadly used to improve food safety, although they can lead to adverse health effects on consumers. Various food processing approaches, at the industrial or domestic level, have been found to highly reduce the amount of pesticide residues in most food materials. In this work, samples of raw tomatoes were collected directly from the field and processed at the industrial level to produce purée, triple concentrated paste, fine pulp, and diced tomatoes. A multiresidue method based on a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged e Safe) sample preparation, followed by liquid chromatography‐tandem mass spectrometry analysis (LC‐MS/MS) for the assessment of 116 pesticides residues, was used. The analytical method has been validated according to SANTE indications. The recovery yields ranged from 75.5% to 115.3%, repeatability (RSDr) ranged from 3.4% to 18.3%, while reproducibility (RSDwR) ranged from 5.4% to 19.8%. The limit of quantifications (LOQs) ranged from 2.35 μg kg−1 for benthiavalicarb to 6.49 μg kg−1 for allethrin. A total of 159 raw tomato samples were collected from the field. The analysis showed the presence of 46 pesticides with azoxystrobin and chlorantraniliprole the most represented. On the other hand, all industrially processed samples showed values ≤ LOD, confirming that post‐harvest processes can lead to a decrease in pesticide residues from agricultural commodities

Oxidative Stress Strongly Restricts the Effect of Codon Choice on the Efficiency of Protein Synthesis in \u3cem\u3eEscherichia coli\u3c/em\u3e

Introduction The response of enterobacteria to oxidative stress is usually considered to be regulated by transcription factors such as OxyR and SoxR. Nevertheless, several reports have shown that under oxidative stress the levels, modification and aminoacylation of tRNAs may be altered suggesting a role of codon bias in regulation of gene expression under this condition. Methods In order to characterize the effects of oxidative stress on translation elongation we constructed a library of 61 plasmids, each coding for the green fluorescent protein (GFP) translationally fused to a different set of four identical codons. Results Using these reporters, we observed that GFP production levels vary widely (~15 fold) when Escherichia coli K-12 is cultured in minimal media as a consequence of codon choice variations. When bacteria are cultured under oxidative stress caused by paraquat the levels of GFP produced by most clones is reduced and, in contrast to control conditions, the range of GFP levels is restricted to a ~2 fold range. Restricting elongation of particular sequences does not increase the range of GFP production under oxidative stress, but altering translation initiation rates leads to an increase in this range. Discussion Altogether, our results suggest that under normal conditions the speed of translation elongation is in the range of the speed of initiation and, consequently, codon choice impacts the speed of protein synthesis. In contrast, under oxidative stress translation initiation becomes much slower than elongation, limiting the speed of translation such that codon choice has at most only subtle effects on the overall output of translation