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The trimeric CCAAT-binding NF-Y is a “pioneer” Transcription Factor -TF- known to cooperate with neighboring TFs to regulate gene expression. Genome-wide analyses detected a precise stereo-alignment ‐10/12 bp- of CCAAT with E-box elements and corresponding colocalization of NF-Y with basic-Helix-Loop-Helix (bHLH) TFs. We dissected here NF-Y interactions with USF1 and MAX. USF1, but not MAX, cooperates in DNA binding with NF-Y. NF-Y and USF1 synergize to activate target promoters. Reconstruction of complexes by structural means shows independent DNA binding of MAX, whereas USF1 has extended contacts with NF-Y, involving the USR, a USF-specific amino acid sequence stretch required for trans-activation. The USR is an intrinsically disordered domain and adopts different conformations based on E-box–CCAAT distances. Deletion of the USR abolishes cooperative DNA binding with NF-Y. Our data indicate that the functionality of certain unstructured domains involves adapting to small variation in stereo-alignments of the multimeric TFs sites.

Objective Plication of the diaphragm is a life-changing procedure for patients affected by diaphragm paralysis. Traditionally, this procedure is performed through a thoracotomy. Access to the diaphragm via this incision is poor and the indications for surgery are limited to patients who can actually sustain such an invasive approach and associated morbidities. A minimally invasive approach was developed to improve the surgical management of diaphragm paralysis. Methods Patients underwent minimally invasive diaphragm plication either by video-assisted or robotic surgery through a 3-port technique with CO2 insufflation. Patients were followed at the routine 6-week clinic and also by telephone consultation 6 to 12 months postoperatively. Data were collected on postoperative complications, postoperative pain or numbness, symptomatic improvement, and change to quality of life following surgery. Results Forty-eight patients underwent 49 minimally invasive diaphragm plication. Median postoperative length of hospital stay was 4 days (range: 2 to 34 days) and there were no cases of mortality. Mean reduction in Medical Research Council dyspnea score per patient was 2.2 points (mode: 3 points). Twenty-eight patients (77.8%) reported a significant symptomatic improvement enabling improvements in quality of life, and 97.2% ( n = 35) were satisfied with the surgical outcome. Conclusions Minimally invasive diaphragm plication is a safe procedure associated with prompt postoperative recovery. It is effective at reducing debilitating dyspnea and improving quality of life.

Current methods for the production of natural vanilla extract are long and tedious, and the efficiency of the vanillin extraction is usually conditioned by different factors during the traditional curing process (temperatures and weather conditions). As an important fraction of vanillin is present in the form of glucovanillin in green beans, endogenous β-glucosidases contribute to its hydrolysis; however, these enzymes lose efficiency during the curing process. The use of extremophilic organisms as a source of an appropriate exogenous enzyme can offer a valid alternative when producing natural vanillin. Here, a β-glucosidase from the thermo-acidophilic organism Alicyclobacillus acidiphilus (AacGH1) was cloned, expressed in E. coli BL21, and fully characterized in respect to both function and crystal structure. Notably, AacGH1 was stable at a temperature up to 50 °C and exhibited good tolerance to glucose, fructose and organic solvents, in particular it maintained full activity in the presence of up to 20 % (v/v) ethanol. The enzyme was then successfully applied to an ethanol-water (20 % (v/v)) extract of green vanilla beans and the complete hydrolysis of glucovanillin (1.7 mM) to vanillin, and other flavour compounds commonly found in vanilla, was achieved using 0.5 mg/mL of enzyme in just 15 min at 30 °C.

Mediastinal malignant pleural mesothelioma with signs of tamponade is rare. Indication for reoperation for recurrent malignant pleural mesothelioma is a controversial but viable option in selected patients. We report a case of a 68-year-old man presenting with epithelioid malignant pleural mesothelioma who underwent a total of three debulking surgeries (pleurectomy/decortication) combined with hyperthermic intrathoracic chemotherapy. Five years after the first procedure, a third urgent operation was performed for recurrence of a large mediastinal mesothelioma causing acute symptoms of pericardial constriction and tamponade. The patient was alive for eight years since the first treatment and 36 months after the second reoperation.

d-Amino acids are the "wrong" enantiomers of amino acids as they are not used in proteins synthesis but evolved in selected functions. On this side, d-aspartate (d-Asp) plays several significant roles in mammals, especially as an agonist of N-methyl-d-aspartate receptors (NMDAR), and is involved in relevant diseases, such as schizophrenia and Alzheimer's disease. In vivo modulation of d-Asp levels represents an intriguing task to cope with such pathological states. As little is known about d-Asp synthesis, the only option for modulating the levels is via degradation, which is due to the flavoenzyme d-aspartate oxidase (DASPO). Here we present the first three-dimensional structure of a DASPO enzyme (from human) which belongs to the d-amino acid oxidase family. Notably, human DASPO differs from human d-amino acid oxidase (attributed to d-serine degradation, the main coagonist of NMDAR) showing peculiar structural features (a specific active site charge distribution), oligomeric state and kinetic mechanism, and a higher FAD affinity and activity. These results provide useful insights into the structure-function relationships of human DASPO: modulating its activity represents now a feasible novel therapeutic target.

To study the capability of the CYP17A1 inhibitor abiraterone acetate (AER) to antagonize the androgen receptor (AR) activation in human prostate cancer (PCa) cell lines. T877A-AR-LNCaP, WT-AR-VCaP, AR-negative DU145, and PC3 PCa cell lines were used by MTT and cell count to study the ability of AER and enzalutamide (ENZ) to modify cell viability. The role of ARs in LNCaP was demonstrated through a gene-silencing experiment. The mechanism of AER cytotoxicity in LNCaP cells was studied, as well as the ability of AER to modulate AR gene expression. The in silico docking approach was applied to study the interaction of AER and ENZ with T877A-AR. Through high-performance liquid chromatography, the production of the AER main metabolite Δ4A was studied. AER bound AR in an almost identical manner to that of dihydrotestosterone (DHT). The higher binding energy for AER in T877A-AR could explain the major cytotoxic effect observed in LNCaP cells. The capability of LNCaP cells to synthesize Δ4A could mediate, at least in part, this effect. AER cytotoxicity in LNCaP cells was mainly due to the activation of apoptosis. Further, AER induced modification of AR target gene expression, suggesting a direct effect on AR activity. AER-induced cytotoxicity on PCa cell lines seemed to be mediated by binding with AR. The higher affinity of AER for T877A-AR may suggest a potential role of AER in the management of CRPC carrying this mutation; however, T877A-AR expressing CRPC patients developed AER resistance, probably due to the increase of progesterone.

Nuclear factor Y (NF-Y) is a transcription factor trimer binding to the functionally important CCAAT box, present in promoters of growth-promoting and cell cycle-regulated genes. The regulatory nuclear factor YA (NF-YA) subunit confers sequence-specificity to the histone-like nuclear factor YB/YC dimer. NF-YA harbors 2 serines-Ser320 and Ser326-shown to be phosphorylated by cyclin-dependent kinase 2. High-throughput proteomics data indicate that they are phosphorylated in vivo. Specifically, Ser320 makes structural contacts with the DNA phosphate backbone; Ser320-P is the major NF-YA phosphorylation isoform following overexpression in HeLa cells, increasing upon mitotic arrest. EMSA with recombinant Ala and Glu mutants confirm a role of Ser320, but not Ser326, in stabilization of DNA binding. Transactivation assays of the CCAAT-dependent MDR1 and RHOB promoters show loss in transcription function for Ser320Glu and Ser320Ala NF-YA mutants. Phylogenetic analysis of NF-YA proteins indicates that Ser320 is indeed evolutionarily conserved. We conclude that phosphorylation of this residue belongs to the core mechanisms of DNA-binding control, possibly driven by the necessity to unfasten binding of or to evict NF-Y from CCAAT sites under specific conditions of growth regulation.-Bernardini, A., Lorenzo, M., Nardini, M., Mantovani, R., Gnesutta, N. The phosphorylatable Ser320 of NF-YA is involved in DNA binding of the NF-Y trimer.

Transcription factors are proteins involved in one of the most important molecular processes in living cells: the expression of genes through a mechanism called “transcription”. Transcription factors, their structure, and function are the topic of the seminar which also includes an overview of the current level of knowledge, the potentialities and problems in this research field, and the possible applications.

The study of enzymes from extremophiles arouses interest in Protein Science because of the amazing solutions these proteins adopt to cope with extreme conditions. Recently solved, the structure of the psychrophilic acyl aminoacyl peptidase from Sporosarcina psychrophila (SpAAP) pinpoints a mechanism of dimerization unusual for this class of enzymes. The quaternary structure of SpAAP relies on a domain-swapping mechanism involving the N-terminal A1 helix. The A1 helix is conserved among homologous mesophilic and psychrophilic proteins and its deletion causes the formation of a monomeric enzyme, which is inactive and prone to aggregate. Here, we investigate the dimerization mechanism of SpAAP through the analysis of chimeric heterodimers where a protomer lacking the A1 helix combines with a protomer carrying the inactivated catalytic site. Our results indicate that the two active sites are independent, and that a single A1 helix is sufficient to partially recover the quaternary structure and the activity of chimeric heterodimers. Since catalytically competent protomers are unstable and inactive unless they dimerize, SpAAP reveals as an “obligomer” for both structural and functional reasons.

To survive in cold environments, psychrophilic organisms produce enzymes endowed with high specific activity at low temperature. The structure of these enzymes is usually flexible and mostly thermolabile. In this work, we investigate the structural basis of cold adaptation of a GH42 β-galactosidase from the psychrophilic Marinomonas ef1. This enzyme couples cold activity with astonishing robustness for a psychrophilic protein, for it retains 23% of its highest activity at 5°C and it is stable for several days at 37°C and even 50°C. Phylogenetic analyses indicate a close relationship with thermophilic β-galactosidases, suggesting that the present-day enzyme evolved from a thermostable scaffold modeled by environmental selective pressure. The crystallographic structure reveals the overall similarity with GH42 enzymes, along with a hexameric arrangement (dimer of trimers) not found in psychrophilic, mesophilic, and thermophilic homologues. In the quaternary structure, protomers form a large central cavity, whose accessibility to the substrate is promoted by the dynamic behavior of surface loops, even at low temperature. A peculiar cooperative behavior of the enzyme is likely related to the increase of the internal cavity permeability triggered by heating. Overall, our results highlight a novel strategy of enzyme cold adaptation, based on the oligomerization state of the enzyme, which effectively challenges the paradigm of cold activity coupled with intrinsic thermolability. DATABASE: Structural data are available in the Protein Data Bank database under the accession number 6Y2K.

NF-Y is a transcription factor (TF) comprising three subunits (NF-YA, NF-YB, NF-YC) that binds with high specificity to the CCAAT sequence, a widespread regulatory element in gene promoters of prosurvival, cell-cycle-promoting, and metabolic genes. Tumor cells undergo &ldquo, metabolic rewiring&rdquo, through overexpression of genes involved in such pathways, many of which are under NF-Y control. In addition, NF-YA appears to be overexpressed in many tumor types. Thus, limiting NF-Y activity may represent a desirable anti-cancer strategy, which is an ongoing field of research. With virtual-screening docking simulations on a library of pharmacologically active compounds, we identified suramin as a potential NF-Y inhibitor. We focused on suramin given its high water-solubility that is an important factor for in vitro testing, since NF-Y is sensitive to DMSO. By electrophoretic mobility shift assays (EMSA), isothermal titration calorimetry (ITC), STD NMR, X-ray crystallography, and molecular dynamics (MD) simulations, we showed that suramin binds to the histone fold domains (HFDs) of NF-Y, preventing DNA-binding. Our analyses, provide atomic-level detail on the interaction between suramin and NF-Y and reveal a region of the protein, nearby the suramin-binding site and poorly conserved in other HFD-containing TFs, that may represent a promising starting point for rational design of more specific and potent inhibitors with potential therapeutic applications.

Introduction: Although several Authors have emphasized the importance of surgery to obtain long term survival in malignant pleural mesothelioma (MPM), no study identifies evident reasons to convince surgeons to decide for one or another technique. Aim: prospective randomized bi-centric pilot study to investigate the effects and survival of VATS debulking surgery and HITHOC vs VATS-talc pleurodesis in MPM. Method: Patients with MPM were assigned to 2-groups: a) VATS-talc pleurodesis; b) VATS-PD and HITHOC. Several factors and Kaplan-Meier survival curves have been analyzed. Results: 27 patients, 24 male, mean-age 66 (48-82) were enrolled. All patients were stage I-II. 14 pts in group A, 13 pts group B. Age, stage, histology, early complication, hospital stay and quality of life did not differ. Survival after the operation was 19.6 months (group A) vs 31.6 months (group B). Survival after diagnosis was 19.6 months (group A) vs 33.0 (group B). One and 2-year survival was 57% and 28,6% for group A and 69% and 54% group B. A divergent curve at Kaplan Meier analysis at 3 years (fig 1). One patient of group B underwent 2 reoperation. Mortality was 0. Conclusion: VATS debulking surgery and HITHOC may be preferred in MPM because 3-year survival was longer compared to VATS pleurodesis, while safety and tolerability were similar. This study could stimulate larger randomized studies.

In the modern era, thoracic surgeons are experiencing an increase interest in imaging patterns of early stage lung cancer due to the introduction of the ground glass opacity in clinical practice, and for the necessity to an accurate cancer localization to perform the appropriate type of resection. In this brief review we analyze the latest news regarding imaging patterns of early pulmonary nodules with special emphasis to ground glass opacity.

The advent of helical high-resolution CT scanners, the application of screening programs and the follow-up of patient with oncological history, led to an increasing number of diagnosis of small pulmonary nodule (less than 10 mm in maximum diameter), partially solid nodule or completely ground glass ones. Their management is controversial. Excisional biopsy by mean of video-assisted thoracic surgery is often a viable choice but to locate these lesions intraoperatively can be impossible without the aid of preoperative or intraoperative localization techniques. In this brief review we will analyze the benefit of adopting localization techniques prior to pulmonary resection for small pulmonary lesions and face the advantages and problems with the main techniques described in the literatures.

NF-Y transcription factor comprises three subunits: NF-YA, NF-YB and NF-YC. NF-YB and NF-YC dimerize through their histone fold domain (HFD), which can bind DNA in a non-sequence-specific fashion while serving as a scaffold for NF-YA trimerization. Upon trimerization, NF-YA specifically recognizes the CCAAT box sequence on promoters and enhancers. In plants, each NF-Y subunit is encoded by several genes giving rise to hundreds of potential heterotrimeric combinations. In addition, plant NF-YBs and NF-YCs interact with other protein partners to recognize a plethora of genomic motifs, as the CCT protein family that binds CORE sites. The NF-Y subunit organization and its DNA-binding properties, together with the NF-Y HFD capacity to adapt different protein modules, represent plant-specific features that play a key role in development, growth and reproduction. Despite their relevance, these features are still poorly understood at the molecular level. Here, we present the structures of Arabidopsis and rice NF-YB/NF-YC dimers, and of an Arabidopsis NF-Y trimer in complex with the FT CCAAT box, together with biochemical data on NF-Y mutants. The dimeric structures identify the key residues for NF-Y HFD stabilization. The NF-Y/DNA structure and the mutation experiments shed light on HFD trimerization interface properties and the NF-YA sequence appetite for the bases flanking the CCAAT motif. These data explain the logic of plant NF-Y gene expansion: the trimerization adaptability and the flexible DNA-binding rules serve the scopes of accommodating the large number of NF-YAs, CCTs and possibly other NF-Y HFD binding partners and a diverse audience of genomic motifs.

The value of pulmonary metastasis (PM) resection in the context of controlled primary tumor sites was shown to improve survival of patients if complete resection could be achieved. The surgeon’s approach can be modulated by various parameters pertaining to safety margins including local growth properties, size, spread and location of PMs. Lymph node dissection and assessment is recommended although its impact on survival remains unclear. Thoracoscopic surgery combined to thin slice chest CT scans has shown results comparable to thoracotomy in patients with few PMs. The management of PMs should therefore be discussed on an individual, interdisciplinary basis to offer the best possible oncological and surgical results as well as to maximize long term patient survival rates.

Graphical abstract 1These authors contributed equally as First Author., While the functions of the recently discovered cytoglobin, ubiquitously expressed in vertebrate tissues, remain uncertain, Antarctic fish provide unparalleled models to study novel protein traits that may arise from cold adaptation. We report here the spectral, ligand-binding and enzymatic properties (peroxynitrite isomerization, nitrite-reductase activity) of cytoglobin-1 from two Antarctic fish, Chaenocephalus aceratus and Dissostichus mawsoni, and present the crystal structure of D. mawsoni cytoglobin-1. The Antarctic cytoglobins-1 display high O2 affinity, scarcely compatible with an O2-supply role, a slow rate constant for nitrite-reductase activity, and do not catalyze peroxynitrite isomerization. Compared with mesophilic orthologues, the cold-adapted cytoglobins favor binding of exogenous ligands to the hexa-coordinated bis-histidyl species, a trait related to their higher rate constant for distal-His/heme-Fe dissociation relative to human cytoglobin. At the light of a remarkable 3D-structure conservation, the observed differences in ligand-binding kinetics may reflect Antarctic fish cytoglobin-1 specific features in the dynamics of the heme distal region and of protein matrix cavities, suggesting adaptation to functional requirements posed by the cold environment. Taken together, the biochemical and biophysical data presented suggest that in Antarctic fish, as in humans, cytoglobin-1 unlikely plays a role in O2 transport, rather it may be involved in processes such as NO detoxification.

Ice-binding proteins (IBPs) bind to ice crystals and control their growth, enabling host organisms to adapt to subzero temperatures. By binding to ice, IBPs can affect the shape and recrystallization of ice crystals. The shapes of ice crystals produced by IBPs vary and are partially due to which ice planes the IBPs are bound to. Previously, we have described a bacterial IBP found in the metagenome of the symbionts of Euplotes focardii ( EfcIBP). EfcIBP shows remarkable ice recrystallization inhibition activity. As recrystallization inhibition of IBPs and other materials are important to the cryopreservation of cells and tissues, we speculate that the EfcIBP can play a future role as an ice recrystallization inhibitor in cryopreservation applications. Here we show that EfcIBP results in a Saturn-shaped ice burst pattern, which may be due to the unique ice-plane affinity of the protein that we elucidated using the fluorescent-based ice-plane affinity analysis. EfcIBP binds to ice at a speed similar to that of other moderate IBPs (5 ± 2 mM-1 s-1); however, it is unique in that it binds to the basal and previously unobserved pyramidal near-basal planes, while other moderate IBPs typically bind to the prism and pyramidal planes and not basal or near-basal planes. These insights into EfcIBP allow a better understanding of the recrystallization inhibition for this unique protein

Arabidopsis thaliana glutamate receptor-like (GLR) channels are amino acid-gated ion channels involved in physiological processes including wound signaling, stomatal regulation, and pollen tube growth. Here, fluorescence microscopy and genetics were used to confirm the central role of GLR3.3 in the amino acid-elicited cytosolic Ca(2+) increase in Arabidopsis seedling roots. To elucidate the binding properties of the receptor, we biochemically reconstituted the GLR3.3 ligand-binding domain (LBD) and analyzed its selectivity profile; our binding experiments revealed the LBD preference for l-Glu but also for sulfur-containing amino acids. Furthermore, we solved the crystal structures of the GLR3.3 LBD in complex with 4 different amino acid ligands, providing a rationale for how the LBD binding site evolved to accommodate diverse amino acids, thus laying the grounds for rational mutagenesis. Last, we inspected the structures of LBDs from nonplant species and generated homology models for other GLR isoforms. Our results establish that GLR3.3 is a receptor endowed with a unique amino acid ligand profile and provide a structural framework for engineering this and other GLR isoforms to investigate their physiology.

Metastatic uterine cancer is a form of systemic disease. As for other solid tumours, it is advocated by some authors that in selected patients, lung metastasectomy may play a role in long-term disease control. The practice of lung metastasectomy is however open to criticism as there is lack of convincing evidence, and over-encouraging outcomes may be attributed to intrinsic selection bias. The case of metastatic uterine tumours is reviewed in the light of the available literature, in order to identify common patterns and prognostic factors that may influence and determine an individualised and informed patient decision.

The recently determined crystal structures of the sequence-specific transcription factor NF-Y have illuminated the structural mechanism underlying transcription at the CCAAT box. NF-Y is a trimeric protein complex composed by the NF-YA, NF-YB, and NF-YC subunits. NF-YB and NF-YC contain a histone-like domain and assemble on a head-to-tail fashion to form a dimer, which provides the structural scaffold for the DNA sugar-phosphate backbone binding (mimicking the nucleosome H2A/H2B-DNA assembly) and for the interaction with NF-YA. The NF-YA subunit hosts two structurally extended α-helices; one is involved in NF-YB/NF-YC binding and the other inserts deeply into the DNA minor groove, providing exquisite sequence-specificity for recognition and binding of the CCAAT box. The analysis of these structural data is expected to serve as a powerful guide for future experiments aimed at understanding the role of post-translational modification at NF-Y regulation sites and to unravel the three-dimensional architecture of higher order complexes formed between NF-Y and other transcription factors that act synergistically for transcription activation. Moreover, these structures represent an excellent starting point to challenge the formation of a stable hybrid nucleosome between NF-Y and core histone proteins, and to rationalize the fine molecular details associated with the wide combinatorial association of plant NF-Y subunits. This article is part of a Special Issue entitled: Nuclear Factor Y in Development and Disease, edited by Prof. Roberto Mantovani.

Plants acquire potassium (K+) ions for cell growth and movement via regulated diffusion through K(+)channels. Here, we present crystallographic and functional data showing that the K(+)inward rectifier KAT1 (K(+)Arabidopsis thaliana 1) channel is regulated by 14-3-3 proteins and further modulated by the phytotoxin fusicoccin, in analogy to the H+-ATPase. We identified a 14-3-3 mode III binding site at the very C terminus of KAT1 and cocrystallized it with tobacco [Nicotiana tabacum) 14-3-3 proteins to describe the protein complex at atomic detail. Validation of this interaction by electrophysiology shows that 14-3-3 binding augments KAT1 conductance by increasing the maximal current and by positively shifting the voltage dependency of gating. Fusicoccin potentiates the 14-3-3 effect on KAT1 activity by stabilizing their interaction. Crystal structure of the ternary complex reveals a noncanonical binding site for the toxin that adopts a novel conformation. The structural insights underscore the adaptability of fusicoccin, predicting more potential targets than so far anticipated. The data further advocate a common mechanism of regulation of the proton pump and a potassium channel, two essential elements in K(+)uptake in plant cells.

Several studies have demonstrated that for complex surgical procedures, surgeons who treat more patients have better outcomes than their lower-volume counterparts. The aim of this paper is to review the experience with video-assisted thoracic surgery (VATS) lobectomies in our small thoracic unit (group A), to understand whether our short-term results were different to the outcomes obtained by the same surgeon previously working in a high-volume unit (group B). 37 patients underwent VATS lobectomy. Hospital stay was on average 4.5 days (group A) versus 4.1 days (group B). Operative time and the number of ‘frozen sections’ were higher in group A. Hospital mortality was 0. VATS lobectomies are a safe approach in a low-volume unit formed by a single surgeon with a previous high-volume experience.

Since 1998, we started a clinical program for awake video-assisted thoracic surgery in our unit using four-step local anesthesia and sedation. Throughout the years, we experienced several difficult cases, three of them had complications postpneumonectomy. The aim of this paper is to report these three cases.

A 70-year-old lady, an ex-smoker, was referred with a 3-month history of a non-productive cough. Her past medical history included hypertension, type II diabetes mellitus and marginal zone lymphoma of the skin in 2015. The computed tomography (CT) thorax reported a nodule posterior to the right bronchus intermedius measuring 28 mm with prominent sub carinal lymph nodes. Positron emission tomography (PET) scan showed the nodule to be FDG avid with no other sites of local or distant disease identified. Her lung function tests were satisfactory. The biopsy of the right peribronchial lymph node taken via endobronchial ultrasound (EBUS) showed no carcinoma but low-grade lymphoma was not excluded.

Sleep deprivation and the consequent circadian clock disruption has become an emergent health question being associated with premature aging and earlier chronic diseases onset. Night-shift work leads to circadian clock misalignment, which is linked to several age-related diseases. However, mechanisms of this association are not well understood. Aim of this study is to explore in night-shift workers early indicators of oxidative stress response and biological aging [oxidized/methylated DNA bases and leukocytes telomere length (LTL)] and late indicators of functional aging [lung function measurements (FEV1 and FVC)] in relation to personal evaluation of work capacity, measured by work ability index (WAI). One hundred fifty-five hospital workers were studied within the framework of a cross-sectional study. We collected physiological, pathological, and occupational history including pack-years, alcohol consumption, physical activity, and night shifts, together with blood and urine samples. Relationships were appraised by univariate and multivariate ordered-logistic regression models. We found that workers with good and excellent WAI present higher FEV1 (p< 0.01) and number of night-work shifts (p

Aims: Structural and functional characterization of the globin coupled sensors (GCS) of Azotobacter vinelandii (AvGReg) and Bordetella pertussis (BpeGReg). Results: UV/Vis and RR spectroscopies confirm the presence in AvGReg and BpeGReg of a globin domain capable of reversible gaseous ligand binding. In AvGReg an influence of the transmitter domain on the heme proximal region of the globin domain can be seen, and k'CO is higher than for other GCSs. The O2 binding kinetics suggest the presence of an open and a closed conformation. As for BpeGReg, the fully oxygenated AvGReg show a very high DGC activity. The CO rebinding to BpeGReg indicates that intra- and intermolecular interactions influence the ligand binding. The globin domains of both proteins (AvGReg-Gb and BpeGreg-Gb*) share the same GCS fold, a similar proximal but a different distal side structure. They homodimerize through a G-H helical bundle as in other GCS. However, BpeGReg-Gb* shows also a second dimerization mode. Innovation: This paper extends our knowledge on the GCS proteins and contributes to a better understanding of the GCSs' role in the formation of bacterial biofilms. Conclusions: AvGReg and BpeGreg conform to the GCS family, share a similar overall structure but they have different properties in terms of the ligand binding. In particular, AvGreg shows an open and closed conformation that in the latter form will very tightly bind oxygen. BpeGReg has only one closed conformation. In both proteins, it is the fully oxygenated GCS form that catalyzes the production of the second messenger.