Complex Lifestyle Research Articles

Thalassoglobus polymorphus sp. nov., a novel Planctomycete isolated close to a public beach of Mallorca Island

Access to axenic cultures is crucial to extend the knowledge of the biology, lifestyle or metabolic capabilities of bacteria from different phyla. The phylum Planctomycetes is an excellent example since its members display an unusual cell biology and complex lifestyles. As a contribution to the current collection of axenic planctomycete cultures, here we describe strain Mal48T isolated from phytoplankton material sampled at the coast of S’Arenal close to Palma de Mallorca (Spain). The isolated strain shows optimal growth at pH 7.0–7.5 and 30 °C and exhibits typical features of Planctomycetes. Cells of the strain are spherical to pear-shaped, divide by polar budding with daughter cells showing the same shape as the mother cell, tend to aggregate, display a stalk and produce matrix or fimbriae. Strain Mal48T showed 95.8% 16S rRNA gene sequence similarity with the recently described Thalassoglobus neptunius KOR42T. The genome sequence of the novel isolate has a size of 6,357,355 bp with a G+C content of 50.3%. A total of 4874 protein-coding genes, 41 tRNA genes and 2 copies of the 16S rRNA gene are encoded in the genome. Based on phylogenetic, morphological and physiological analyses, we conclude that strain Mal48T (= DSM 100737T = LMG 29019T) should be classified as the type strain of a new species in the genus Thalassoglobus, for which the name Thalassoglobus polymorphus sp. nov. is proposed.

Associations of noise kurtosis, genetic variations in NOX3 and lifestyle factors with noise-induced hearing loss

BackgroundNoise-induced hearing loss (NIHL) is a complex disease caused by environmental and genetic risk factors. This study was to explore the association of noise kurtosis, triphosphopyridine nucleotide oxidase 3 (NOX3) and lifestyles with NIHL.MethodsThis case-control study included 307 patients with NIHL and 307 matched control individuals from Zhejiang province of China. General characteristics, noise exposure data, the exfoliated cells of the oral mucosa, and lifestyle details of individuals were collected. The kompetitive allele specific polymerase chain reaction (KASP) method was used to analyze the genotypes of three single nucleotide polymorphisms (SNPs) of NOX3.ResultsPeople who exposed to complex noise had a higher risk of NIHL than those exposed to steady noise (adjusted: OR = 1.806, P = 0.002). The GT genotype of additive model and TT + GT genotype of dominant model in NOX3 rs12195525 decreased the risk of NIHL (adjusted: OR = 0.618, P = 0.043; OR = 0.622, P = 0.036). Smoking and exposure to high video volume increased the risk of NIHL (adjusted: OR = 1.486, P = 0.038; OR = 1.611, P = 0.014). Oppositely, regular physical exercise decreased the risk of NIHL (adjusted: OR = 0.598, P = 0.004). A positive interaction was found between complex noise and lifestyles including high video volume exposure and no physical exercise in the additive models (RERI = 1.088, P < 0.001; RERI = 1.054, P = 0.024). A positive interaction was also found between NOX3 rs12195525 GG genotype and lifestyles including smoking and high video volume exposure in the additive models (RERI = 1.042, P = 0.005; RERI = 0.774, P = 0.044).ConclusionsNoise temporal structure, NOX3 rs12195525 polymorphism, and the three lifestyles of smoking, video volume, and physical exercise were related to the NIHL. There were the interactions between noise temporal structure and the lifestyle of video volume or physical exercise, as well as between NOX3 and the lifestyle of smoking or video volume. These results provide a theoretical basis for the prevention and genetic testing of NIHL.

Blastopirellula retiformator sp. nov. isolated from the shallow-sea hydrothermal vent system close to Panarea Island.

Aquatic bacteria belonging to the deep-branching phylum Planctomycetes play a major role in global carbon and nitrogen cycles. However, their uncommon morphology and physiology, and their roles and survival on biotic surfaces in marine environments, are only partially understood. Access to axenic cultures of different planctomycetal genera is key to study their complex lifestyles, uncommon cell biology and primary and secondary metabolism in more detail. Here, we describe the characterisation of strain Enr8T isolated from a marine biotic surface in the seawater close to the shallow-sea hydrothermal vent system off Panarea Island, an area with high temperature and pH gradients, and high availability of different sulphur and nitrogen sources resulting in a great microbial diversity. Strain Enr8T showed typical planctomycetal traits such as division by polar budding, aggregate formation and presence of fimbriae and crateriform structures. Growth was observed at ranges of 15-33°C (optimum 30°C), pH 6.0-8.0 (optimum 7.0) and at NaCl concentrations from 100 to 1200mM (optimum 350-700mM). Strain Enr8T forms white colonies on solid medium and white flakes in liquid culture. Its genome has a size of 6.20Mb and a G + C content of 59.2%. Phylogenetically, the strain belongs to the genus Blastopirellula. We propose the name Blastopirellula retiformator sp. nov. for the novel species, represented by the type strain Enr8T (DSM 100415T = LMG 29081T).

Three marine strains constitute the novel genus and species Crateriforma conspicua in the phylum Planctomycetes.

Planctomycetes is a ubiquitous phylum of mostly aquatic bacteria that have a complex lifestyle and an unusual cell biology. Here, we describe three strains of the same novel genus and species isolated from three different environments; from a red biofilm at a hydrothermal vent in the Mediterranean Sea, from sediment in a salt-water fish tank, and from the surface of algae at the coast of the Balearic island Mallorca. The three strains Mal65T (DSM 100706T = LMG 29792T, Pan14r (DSM 29351 = LMG 29012), and V7 (DSM 29812 = CECT 9853 = VKM B-3427) show typical characteristics of the Planctomycetaceae family, such as cell division by budding, crateriform structures and growth in aggregates or rosettes. The strains are mesophilic, neutrophilic to alkaliphilic as well as chemoheterotrophic and exhibit doubling times between 12 and 35h. Based on our phylogenetic analysis, the three strains represent a single novel species of a new genus, for which we propose the name Crateriforma conspicua gen. nov. sp. nov.

Description of three bacterial strains belonging to the new genus Novipirellula gen. nov., reclassificiation of Rhodopirellula rosea and Rhodopirellula caenicola and readjustment of the genus threshold of the phylogenetic marker rpoB for Planctomycetaceae.

Access to axenic cultures of Planctomycetes is crucial for further investigating their complex lifestyle, uncommon cell biology and primary and secondary metabolism. As a contribution to achieve this goal in the future, we here describe three strains belonging to the novel genus Novipirellula gen. nov. The strains were isolated from biotic and abiotic surfaces in the Baltic Sea and from the island Heligoland in the North Sea. Colony colours range from white to light pink. Cells are acorn-shaped and grew optimally at neutral pH and temperatures between 27 and 30°C. Phylogenetic analyses revealed that the isolated strains represent three novel species belonging to a new genus, Novipirellula gen. nov. Beyond that, our analysis suggests that Rhodopirellula rosea LHWP3T, Rhodopirellula caenicola YM26-125T and Rhodopirellula maiorica SM1 are also members of this novel genus. Splitting the current genus Rhodopirellula into a more strictly defined genus Rhodopirellula and Novipirellula also allowed readjusting the genus threshold value for the gene rpoB, encoding the RNA polymerase β-subunit, which is used as phylogenetic marker for Planctomycetales. A threshold range of 75.5-78% identity of the analysed partial rpoB sequence turned out to be reliable for differentiation of genera within the family Planctomycetaceae.

Three novel Rubripirellula species isolated from plastic particles submerged in the Baltic Sea and the estuary of the river Warnow in northern Germany.

Planctomycetes are a unique and important phylum containing mostly aquatic bacteria, which are often associated with phototrophic surfaces. A complex lifestyle, their potential for the production of bioactive small molecules, their unusual cell biology and a large number of giant and hypothetical genes in their genomes make these microorganisms a fascinating topic for further research. Here, we characterise three novel planctomycetal strains isolated from polystyrene and polyethylene particles that were submerged in the German part of the Baltic Sea and the estuary of the river Warnow. All three strains showed typical planctomycetal traits such as division by polar budding and formation of rosettes. The isolated strains were mesophilic and neutrophilic chemoheterotrophs and reached generation times of 10-25h during laboratory-scale cultivation. Taxonomically, the three strains belong to the genus Rubripirellula. Based on our analyses all three strains represent novel species, for which we propose the names Rubripirellula amarantea sp. nov., Rubripirellula tenax sp. nov. and Rubripirellula reticaptiva sp. nov. The here characterised strains Pla22T (DSM 102267T = LMG 29691T), Poly51T (DSM 103356T = VKM B-3438T) and Poly59T (DSM 103767T = LMG 29696T) are the respective type strains of these novel species. We also emend the description of the genus Rubripirellula.

Rhodopirellula heiligendammensis sp. nov., Rhodopirellula pilleata sp. nov., and Rhodopirellula solitaria sp. nov. isolated from natural or artificial marine surfaces in Northern Germany and California, USA, and emended description of the genus Rhodopirellula.

Expanding the collection of Planctomycetes by characterisation of novel species is key to better understanding of their complex lifestyles, uncommon cell biology and unexplored metabolism. Here, we isolated three novel planctomycetal strains from a kelp forest on the California Coastline at Monterey Bay or from plastic surfaces submerged in the Baltic Sea and the estuary of the river Warnow in the northeast of Germany. According to our phylogenetic analysis, the isolated strains Poly21T, Pla100T and CA85T represent three novel species within the genus Rhodopirellula. All three show typical planctomycetal traits such as division by budding. All are aerobic, mesophilic chemoheterotrophs and show genomic features comparable to other described Rhodopirellula species. However, strain CA85T is exceptional as it forms cream colonies, but no aggregates, which is a notable deviation from the pink- to red-pigmented and aggregate-forming Rhodopirellula species known thus far. We propose the names Rhodopirellula heiligendammensis sp. nov., Rhodopirellula pilleata sp. nov., and Rhodopirellula solitaria sp. nov. for the novel strains Poly21T (DSM 102266T = LMG 29467T = CECT 9847T = VKM B-3435T), Pla100T (DSM 102937T = LMG 29465T) and CA85T (DSM 109595T = LMG 29699T = VKM B-3451T), respectively, which we present as the respective type strains of these novel species.

Smart Dashboards for Smart City—A Platform to Engage with Citizen

Smart City is the term composed for a city that aggressively balances itself through ICT based urban solutions and solving multiple problems faced by the ever complex urban lifestyle. Big data analytics is one of the best innovation to process extracted data from this Internet of Things (IoT) Ecosystem of the smart city. In this ecosystem, the communication and engagement with the city residents are very important. The smart dashboard is a hyper connected platform to effectively project the smart city dimension’s performance to stakeholder and residents. Thus creating an instant engagement with the citizens. Although most of the smart cities has been computing all the data gathered in the city using the most sophisticated data analytics tools, it has not effectively interfaced it to the benefit of city residents. A Smart Dashboard is seen as an enabler to the smart city dimensions but many of the current smart dashboards are still elusive and faces many challenges. There will be discussions about the importance of smart dashboard, a list of key indicators and the challenges to implementing this dashboard.

Bartonella gene transfer agent: Evolution, function, and proposed role in host adaptation.

The processes underlying host adaptation by bacterial pathogens remain a fundamental question with relevant clinical, ecological, and evolutionary implications. Zoonotic pathogens of the genus Bartonella constitute an exceptional model to study these aspects. Bartonellae have undergone a spectacular diversification into multiple species resulting from adaptive radiation. Specific adaptations of a complex facultative intracellular lifestyle have enabled the colonisation of distinct mammalian reservoir hosts. This remarkable host adaptability has a multifactorial basis and is thought to be driven by horizontal gene transfer (HGT) and recombination among a limited genus‐specific pan genome. Recent functional and evolutionary studies revealed that the conserved Bartonella gene transfer agent (BaGTA) mediates highly efficient HGT and could thus drive this evolution. Here, we review the recent progress made towards understanding BaGTA evolution, function, and its role in the evolution and pathogenesis of Bartonella spp. We notably discuss how BaGTA could have contributed to genome diversification through recombination of beneficial traits that underlie host adaptability. We further address how BaGTA may counter the accumulation of deleterious mutations in clonal populations (Muller's ratchet), which are expected to occur through the recurrent transmission bottlenecks during the complex infection cycle of these pathogens in their mammalian reservoir hosts and arthropod vectors.

A Role for the VPS Retromer in Brucella Intracellular Replication Revealed by Genomewide siRNA Screening.

Brucella, the agent causing brucellosis, is a major zoonotic pathogen with worldwide distribution. Brucella resides and replicates inside infected host cells in membrane-bound compartments called Brucella-containing vacuoles (BCVs). Following uptake, Brucella resides in endosomal BCVs (eBCVs) that gradually mature from early to late endosomal features. Through a poorly understood process that is key to the intracellular lifestyle of Brucella, the eBCV escapes fusion with lysosomes by transitioning to the replicative BCV (rBCV), a replicative niche directly connected to the endoplasmic reticulum (ER). Despite the notion that this complex intracellular lifestyle must depend on a multitude of host factors, a holistic view on which of these components control Brucella cell entry, trafficking, and replication is still missing. Here we used a systematic cell-based small interfering RNA (siRNA) knockdown screen in HeLa cells infected with Brucella abortus and identified 425 components of the human infectome for Brucella infection. These include multiple components of pathways involved in central processes such as the cell cycle, actin cytoskeleton dynamics, or vesicular trafficking. Using assays for pathogen entry, knockdown complementation, and colocalization at single-cell resolution, we identified the requirement of the VPS retromer for Brucella to escape the lysosomal degradative pathway and to establish its intracellular replicative niche. We thus validated the VPS retromer as a novel host factor critical for Brucella intracellular trafficking. Further, our genomewide data shed light on the interplay between central host processes and the biogenesis of the Brucella replicative niche.IMPORTANCE With >300,000 new cases of human brucellosis annually, Brucella is regarded as one of the most important zoonotic bacterial pathogens worldwide. The agent causing brucellosis resides inside host cells within vacuoles termed Brucella-containing vacuoles (BCVs). Although a few host components required to escape the degradative lysosomal pathway and to establish the ER-derived replicative BCV (rBCV) have already been identified, the global understanding of this highly coordinated process is still partial, and many factors remain unknown. To gain deeper insight into these fundamental questions, we performed a genomewide RNA interference (RNAi) screen aiming at discovering novel host factors involved in the Brucella intracellular cycle. We identified 425 host proteins that contribute to Brucella cellular entry, intracellular trafficking, and replication. Together, this study sheds light on previously unknown host pathways required for the Brucella infection cycle and highlights the VPS retromer components as critical factors for the establishment of the Brucella intracellular replicative niche.

Executive Function Impairments in Adolescents With Obesity and Obstructive Sleep Apnea Syndrome.

Adolescents with obesity and obstructive sleep apnea syndrome (OSAS) are at high risk of poor physical and cognitive health consequences. The purpose of this study was to explore executive function (EF) in adolescents with obesity and OSAS, describe physical activity and sleep duration, and explore the relationships between EF and physical activity and sleep duration. Participants comprised 20 adolescents (ages 11-17 years) with obesity (body mass index [BMI] ≥ 95th percentile) and OSAS (apnea-hypopnea index [AHI] ≥ 1.5 events/hr) participated in this observational pilot study with a prospective 1-week measurement protocol. Outcome measures included EF by the Behavior Rating Inventory of Executive Function-2, physical activity by Previous Day Physical Activity Recall, and sleep by Consensus Sleep Diary and actigraphy. Adolescents with obesity and OSAS had significantly worse EF by self- and parent-report than the normative sample (p ≤ .003), 45% had impaired EF and up to 30% had clinically significant impairments. Participants spent approximately 14.3 hr/day in light-intensity activity, and 33% did not engage in moderate-to-vigorous-intensity activity for at least 60 min on any days of data collection. Adolescents had insufficient sleep duration, averaging 6.9 hr/night. No significant relationships were identified between physical activity or sleep duration and EF. Providers should have a heightened awareness for EF impairments in obese adolescents with OSAS and consider how EF deficits may affect uptake and adherence to complex lifestyle and/or medical interventions among these patients.

“Don’t sweat it buddy, it’s OK”: an exploration of the needs of adolescents with disabilities when designing a mobile application for weight management and healthy lifestyles

Purpose: Adolescents with disabilities often demonstrate higher sedentary behaviours, lower physical activity levels, poorer quality diets, and higher rates of overweight and obesity than typically developing youth. This study had two objectives: 1) To understand the needs and priorities of adolescents with disabilities, parents, and the healthcare professionals who work with them around healthy lifestyles and weight management; and 2) To explore whether and how a mobile application could address these needs.Methods: Multiple perspectives were gathered through separate qualitative focus groups with adolescents with disabilities (12–17 years), parents, and rehabilitation healthcare professionals. Data were analysed using descriptive thematic analysis.Results: Parents (n = 6) and healthcare professionals (n = 9) described the complex needs of adolescents with disabilities around weight management and healthy lifestyles, including balancing differing priorities and a lack of appropriate resources. Adolescents (n = 7) endorsed the potential for technology to enhance their health through empowerment and having a virtual support system. All stakeholder groups endorsed taking a holistic, wellness approach.Conclusions: Adolescents with disabilities have a complex lifestyle and weight management needs, but mobile applications have the potential to provide individualized support. It is critical that anyone developing mobile applications engage a range of stakeholders as co-designers.Implications for rehabilitationAdolescents with disabilities have complex support needs and priorities around weight management and healthy lifestyles.Existing resources do not take into account the wide-ranging abilities of adolescents with disabilities.Mobile applications have the potential to empower adolescents and provide tailored support around healthy lifestyles.Including user input when designing technologies is critical.

In silico characterization of a novel putative aerotaxis chemosensory system in the myxobacterium, Corallococcus coralloides

BackgroundAn efficient signal transduction system allows a bacterium to sense environmental cues and then to respond positively or negatively to those signals; this process is referred to as taxis. In addition to external cues, the internal metabolic state of any bacterium plays a major role in determining its ability to reside and thrive in its current environment. Similar to external signaling molecules, cytoplasmic signals are also sensed by methyl-accepting chemotaxis proteins (MCPs) via diverse ligand binding domains. Myxobacteria are complex soil-dwelling social microbes that can perform a variety of physiologic and metabolic activities ranging from gliding motility, sporulation, biofilm formation, carotenoid and secondary metabolite biosynthesis, predation, and slime secretion. To live such complex lifestyles, they have evolved efficient signal transduction systems with numerous one- and two-component regulatory system along with a large array of chemosensory systems to perceive and integrate both external and internal cues.ResultsHere we report the in silico characterization of a putative energy taxis cluster, Cc-5, which is present in only one amongst 34 known and sequenced myxobacterial genomes, Corallococcus coralloides. In addition, we propose that this energy taxis cluster is involved in oxygen sensing, suggesting that C. coralloides can sense (either directly or indirectly) and then respond to changing concentrations of molecular oxygen.ConclusionsThis hypothesis is based on the presence of a unique MCP encoded in this gene cluster that contains two different oxygen-binding sensor domains, PAS and globin. In addition, the two monooxygenases encoded in this cluster may contribute to aerobic respiration via ubiquinone biosynthesis, which is part of the cytochrome bc1 complex. Finally, we suggest that this cluster was acquired from Actinobacteria, Gammaproteobacteria or Cyanobacteria. Overall, this in silico study has identified a potentially innovative and evolved mechanism of energy taxis in only one of the myxobacteria, C. coralloides.

A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants.

The complex lifestyle, evolutionary history of advanced cooperation, and disease defenses of leaf-cutting ants are well studied. Although numerous studies have described the behaviors connected with disease defense, and the associated use of chemicals and antimicrobials, no common visual reference has been made. The main aim of this study was to record short clips of behaviors involved in disease defense, both prophylactically and directly targeted towards an antagonist of the colony following infection. To do so we used an infection experiment, with sub-colonies of the leaf-cutting ant species Acromyrmex echinatior, and the most significant known pathogenic threat to the ants' fungal crop (Leucoagaricus gongylophorus), a specialized pathogenic fungus in the genus Escovopsis. We filmed and compared infected and uninfected colonies, at both early and more advanced stages of infection. We quantified key defensive behaviors across treatments and show that the behavioral response to pathogen attack likely varies between different castes of worker ants, and between early and late detection of a threat. Based on these recordings we have made a library of behavioral clips, accompanied by definitions of the main individual defensive behaviors. We anticipate that such a guide can provide a common frame of reference for other researchers working in this field, to recognize and study these behaviors, and also provide greater scope for comparing different studies to ultimately help better understand the role these behaviors play in disease defense.

A Visual Guide for Studying Behavioral Defenses to Pathogen Attacks in Leaf-Cutting Ants

The complex lifestyle, evolutionary history of advanced cooperation, and disease defenses of leaf-cutting ants are well studied. Although numerous studies have described the behaviors connected with disease defense, and the associated use of chemicals and antimicrobials, no common visual reference has been made. The main aim of this study was to record short clips of behaviors involved in disease defense, both prophylactically and directly targeted towards an antagonist of the colony following infection. To do so we used an infection experiment, with sub-colonies of the leaf-cutting ant species Acromyrmex echinatior, and the most significant known pathogenic threat to the ants' fungal crop (Leucoagaricus gongylophorus), a specialized pathogenic fungus in the genus Escovopsis. We filmed and compared infected and uninfected colonies, at both early and more advanced stages of infection. We quantified key defensive behaviors across treatments and show that the behavioral response to pathogen attack likely varies between different castes of worker ants, and between early and late detection of a threat. Based on these recordings we have made a library of behavioral clips, accompanied by definitions of the main individual defensive behaviors. We anticipate that such a guide can provide a common frame of reference for other researchers working in this field, to recognize and study these behaviors, and also provide greater scope for comparing different studies to ultimately help better understand the role these behaviors play in disease defense.

High-Resolution Analysis of the Peptidoglycan Composition in Streptomyces coelicolor.

The bacterial cell wall maintains cell shape and protects against bursting by turgor. A major constituent of the cell wall is peptidoglycan (PG), which is continuously modified to enable cell growth and differentiation through the concerted activity of biosynthetic and hydrolytic enzymes. Streptomycetes are Gram-positive bacteria with a complex multicellular life style alternating between mycelial growth and the formation of reproductive spores. This involves cell wall remodeling at apical sites of the hyphae during cell elongation and autolytic degradation of the vegetative mycelium during the onset of development and antibiotic production. Here, we show that there are distinct differences in the cross-linking and maturation of the PGs between exponentially growing vegetative hyphae and the aerial hyphae that undergo sporulation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis identified over 80 different muropeptides, revealing that major PG hydrolysis takes place over the course of mycelial growth. Half of the dimers lacked one of the disaccharide units in transition-phase cells, most likely due to autolytic activity. The deacetylation of MurNAc to MurN was particularly pronounced in spores and strongly reduced in sporulation mutants with a deletion of bldD or whiG, suggesting that MurN is developmentally regulated. Altogether, our work highlights the dynamic and growth phase-dependent changes in the composition of the PG in StreptomycesIMPORTANCE Streptomycetes are bacteria with a complex lifestyle and are model organisms for bacterial multicellularity. From a single spore, a large multigenomic multicellular mycelium is formed, which differentiates to form spores. Programmed cell death is an important event during the onset of morphological differentiation. In this work, we provide new insights into the changes in the peptidoglycan composition and over time, highlighting changes over the course of development and between growing mycelia and spores. This revealed dynamic changes in the peptidoglycan when the mycelia aged, with extensive peptidoglycan hydrolysis and, in particular, an increase in the proportion of 3-3 cross-links. Additionally, we identified a muropeptide that accumulates predominantly in the spores and may provide clues toward spore development.

The Interplay of Host Autophagy and Eukaryotic Pathogens.

For intracellular pathogens, host cells provide a replicative niche, but are also armed with innate defense mechanisms to combat the intruder. Co-evolution of host and pathogens has produced a complex interplay of host-pathogen interactions during infection, with autophagy emerging as a key player in the recent years. Host autophagy as a degradative process is a significant hindrance to intracellular growth of the pathogens, but also can be subverted by the pathogens to provide support such as nutrients. While the role of host cell autophagy in the pathogenesis mechanisms of several bacterial and viral pathogens have been extensively studied, less is known for eukaryotic pathogens. In this review, we focus on the interplay of host autophagy with the eukaryotic pathogens Plasmodium spp, Toxoplasma, Leishmania spp and the fungal pathogens Candida albicans, Aspergillus fumigatus and Cryptococcus neoformans. The differences between these eukaryotic pathogens in terms of the host cell types they infect, infective strategies and the host responses required to defend against them provide an interesting insight into how they respond to and interact with host cell autophagy. Due to the ability to infect multiple host species and cell types during the course of their usually complex lifestyles, autophagy plays divergent roles even for the same pathogen. The scenario is further compounded since many of the eukaryotic pathogens have their own sets of either complete or partial autophagy machinery. Eukaryotic pathogen-autophagy interplay is thus a complex relationship with many novel insights for the basic understanding of autophagy, and potential for clinical relevance.

Evolution of protein trafficking in kinetoplastid parasites: Complexity and pathogenesis

The kinetoplastida and their close relatives are unicellular organisms prevalent within the biosphere and important for significant impacts on global health, economy and ecosystems. They are, under most models, an early branching lineage. Individual species adapted to highly diverse environments by adopting complex life styles; parasitic species can infect a wide range of eukaryotic hosts, while many relatives are free-living and some autotrophic from acquiring a plastid for photosynthesis. Adaptation is especially evident in the evolution of kinetoplastid cell surface architecture and is supported by endomembrane trafficking and serves as a platform for interaction with its environment. Here we summarize and discuss recent genomic and experimental studies of the protein trafficking system in kinetoplastids, with focus on the composition and function of the surface as well as mechanisms for constructing, maintaining and regulating the cell surface proteome. We hope this provides a broad view of how protein trafficking contributes to the intricate and dynamic host-parasite interfaces that are critical for successful environmental adaptation of this highly important lineage.

Global characterization of the Dicer-like protein DrnB roles in miRNA biogenesis in the social amoeba Dictyostelium discoideum

ABSTRACTMicro (mi)RNAs regulate gene expression in many eukaryotic organisms where they control diverse biological processes. Their biogenesis, from primary transcripts to mature miRNAs, have been extensively characterized in animals and plants, showing distinct differences between these phylogenetically distant groups of organisms. However, comparably little is known about miRNA biogenesis in organisms whose evolutionary position is placed in between plants and animals and/or in unicellular organisms. Here, we investigate miRNA maturation in the unicellular amoeba Dictyostelium discoideum, belonging to Amoebozoa, which branched out after plants but before animals. High-throughput sequencing of small RNAs and poly(A)-selected RNAs demonstrated that the Dicer-like protein DrnB is required, and essentially specific, for global miRNA maturation in D. discoideum. Our RNA-seq data also showed that longer miRNA transcripts, generally preceded by a T-rich putative promoter motif, accumulate in a drnB knock-out strain. For two model miRNAs we defined the transcriptional start sites (TSSs) of primary (pri)-miRNAs and showed that they carry the RNA polymerase II specific m7G-cap. The generation of the 3ʹ-ends of these pri-miRNAs differs, with pri-mir-1177 reading into the downstream gene, and pri-mir-1176 displaying a distinct end. This 3´-end is processed to shorter intermediates, stabilized in DrnB-depleted cells, of which some carry a short oligo(A)-tail. Furthermore, we identified 10 new miRNAs, all DrnB dependent and developmentally regulated. Thus, the miRNA machinery in D. discoideum shares features with both plants and animals, which is in agreement with its evolutionary position and perhaps also an adaptation to its complex lifestyle: unicellular growth and multicellular development.

Health behavior-related indicator of lifestyle: application in the ELSA-Brasil study.

Various behaviors are considered health enhancing. Nevertheless, according to the current scientific literature, four health behaviors are considered particularly risky in view of their association with a group of chronic diseases: 1) smoking; 2) excessive alcohol consumption; 3) poor diet; and 4) lack of physical activity. Theoretically, it should be possible to make improvements to one's health by maximizing the number of healthy behaviors and minimizing the unhealthy ones. However, in reality, the different behaviors interconnect to create more complex lifestyles. Therefore, the objective of this paper is to present the construction of a lifestyle indicator based on health behaviors selected in the ELSA-Brazil study. This indicator revealed two lifestyles: less healthy and healthier lifestyles. The model proved adequate and was confirmed using latent class analysis (LCA). Agreement was 83.2 between the indicator and the LCA results, with a kappa coefficient of 0.65. Women were more likely to have a healthier lifestyle than men, reinforcing the scientific consistency of the indicator, since this finding is in agreement with data from the scientific literature. The indicator created to define lifestyle was found to have scientific consistency and validity; therefore, its use can be recommended for future population-based studies concerning the promotion of health and healthy lifestyles.