Regulatory mechanisms controlling morphology and pathogenesis in Candida albicans.
Abstract Candida albicans, a major human fungal pathogen, can cause a wide variety of both mucosal and systemic infections, particularly in immunocompromised individuals. Multiple lines of evidence suggest a strong association between virulence and the ability of C. albicans to undergo a reversible morphological transition from yeast to filamentous cells in response to host environmental cues. Most previous studies on mechanisms important for controlling the C. albicans morphological transition have focused on signaling pathways and sequence-specific transcription factors. However, in recent years a variety of nov...
Source: Current Opinion in Microbiology - May 23, 2019 Category: Microbiology Authors: Kadosh D Tags: Curr Opin Microbiol Source Type: research

The role of Aspergillus fumigatus polysaccharides in host-pathogen interactions.
Abstract Aspergillus fumigatus is a saprophytic mold that can cause infection in patients with impaired immunity or chronic lung diseases. The polysaccharide-rich cell wall of this fungus is a key point of contact with the host immune system. The availability of purified cell wall polysaccharides and mutant strains deficient in the production of these glycans has revealed that these glycans play an important role in the pathogenesis of A. fumigatus infections. Herein, we review our current understanding of the key polysaccharides present within the A. fumigatus cell wall, and their interactions with host cells and...
Source: Current Opinion in Microbiology - May 20, 2019 Category: Microbiology Authors: Zacharias CA, Sheppard DC Tags: Curr Opin Microbiol Source Type: research

Host defense mechanisms against Aspergillus fumigatus lung colonization and invasion.
Abstract The human lung is continually exposed to airborne conidia of the fungus Aspergillus fumigatus (AF) and related species. The innate immune system efficiently eliminates inhaled AF conidia from the lung in normal individuals, but immunocompromised patients are at risk for highly lethal invasive aspergillosis (IA). Some individuals not at risk for IA may still suffer from failed clearance of AF in the form of noninvasive colonization associated with conditions such as allergic bronchopulmonary aspergillosis. Understanding of normal innate immune function against AF as well as failures of these functions will...
Source: Current Opinion in Microbiology - May 16, 2019 Category: Microbiology Authors: Mackel JJ, Steele C Tags: Curr Opin Microbiol Source Type: research

Candida albicans biofilm growth and dispersal: contributions to pathogenesis.
Abstract The fungal species Candida albicans is most frequently associated with biofilm formation in immune-compromised and medically compromised patients, and it is now firmly established that biofilm formation represents a major virulence factor during candidiasis. A growing body of evidence has demonstrated that C. albicans biofilm development is a highly regulated and coordinated process, where adhesive interactions, morphogenetic conversions, and consortial behavior play significant roles. Cells within the biofilms are protected from environmental stresses including host immune defenses and antifungal treatme...
Source: Current Opinion in Microbiology - May 11, 2019 Category: Microbiology Authors: Wall G, Montelongo-Jauregui D, Vidal Bonifacio B, Lopez-Ribot JL, Uppuluri P Tags: Curr Opin Microbiol Source Type: research

Connecting iron regulation and mitochondrial function in Cryptococcus neoformans.
Abstract Iron acquisition is essential for the proliferation of microorganisms, and human pathogens such as the fungus Cryptococcus neoformans must use sophisticated uptake mechanisms to overcome host iron sequestration. Iron is of particular interest for C. neoformans because its availability is an important cue for the elaboration of virulence factors. In fungi, extracellular iron is taken up through high affinity, low affinity, siderophore-mediated, and heme uptake pathways, and the details of these mechanisms are under active investigation in C. neoformans. Following uptake, iron is transported to intracellula...
Source: Current Opinion in Microbiology - May 11, 2019 Category: Microbiology Authors: Horianopoulos LC, Kronstad JW Tags: Curr Opin Microbiol Source Type: research

Corrigendum to "The soil microbiome - from metagenomics to metaphenomics" [Curr Opin Micrbiol 43 (June 2018) 162-168].
Corrigendum to "The soil microbiome - from metagenomics to metaphenomics" [Curr Opin Micrbiol 43 (June 2018) 162-168]. Curr Opin Microbiol. 2019 May 10;: Authors: Jansson JK, Hofmockel KS PMID: 31085071 [PubMed - as supplied by publisher] (Source: Current Opinion in Microbiology)
Source: Current Opinion in Microbiology - May 10, 2019 Category: Microbiology Authors: Jansson JK, Hofmockel KS Tags: Curr Opin Microbiol Source Type: research

Toward computer-made artificial antibiotics.
Abstract Merging concepts from synthetic biology and computational biology may yield antibiotics that are less likely to elicit resistance than existing drugs and that yet can fight drug-resistant infections. Indeed, computer-guided strategies coupled with massively parallel high-throughput experimental methods represent a new paradigm for antibiotic discovery. Infections caused by multidrug-resistant microorganisms are increasingly deadly. In the current post-antibiotic era, many of these infections cannot be treated with our existing antimicrobial arsenal. Furthermore, we may have already exhausted the category ...
Source: Current Opinion in Microbiology - May 10, 2019 Category: Microbiology Authors: Torres MT, de la Fuente-Nunez C Tags: Curr Opin Microbiol Source Type: research

Recent and emerging technologies for the rapid diagnosis of infection and antimicrobial resistance.
Abstract The rise in antimicrobial resistance (AMR) is predicted to cause 10 million deaths per year by 2050 unless steps are taken to prevent this looming crisis. Microbiological culture is the gold standard for the diagnosis of bacterial/fungal pathogens and antimicrobial resistance and takes 48 hours or longer. Hence, antibiotic prescriptions are rarely based on a definitive diagnosis and patients often receive inappropriate treatment. Rapid diagnostic tools are urgently required to guide appropriate antimicrobial therapy, thereby improving patient outcomes and slowing AMR development. We discuss new tec...
Source: Current Opinion in Microbiology - May 8, 2019 Category: Microbiology Authors: Trotter AJ, Aydin A, Strinden MJ, O'Grady J Tags: Curr Opin Microbiol Source Type: research

Unearthing fungal chemodiversity and prospects for drug discovery.
Abstract Natural products have drastically improved our lives by providing an excellent source of molecules to fight cancer, pathogens, and cardiovascular diseases that have revolutionized medicine. Fungi are prolific producers of diverse natural products and several recent advances in synthetic biology, genetics, bioinformatics, and natural product chemistry have greatly enhanced our ability to efficiently mine their genomes for the discovery of novel drugs. In this article, we provide an overview of improved heterologous expression platforms for targeted production of fungal secondary metabolites, of advances in...
Source: Current Opinion in Microbiology - May 6, 2019 Category: Microbiology Authors: Greco C, Keller NP, Rokas A Tags: Curr Opin Microbiol Source Type: research

Expanding, integrating, sensing and responding: the role of primary metabolism in specialised metabolite production.
oskisson PA Abstract Producing specialised metabolites such as antibiotics, immunosuppressives, anti-cancer agents and anti-helminthics draws on primary metabolism to provide the building blocks for biosynthesis. The growth phase-dependent nature of production means that producing organisms must deal with the metabolic conflicts of declining growth rate, reduced nutrient availability, specialised metabolite production and potentially morphological development. In recent years, our understanding of gene expansion events, integration of metabolic function and gene regulation events that facilitate the sensing and re...
Source: Current Opinion in Microbiology - April 18, 2019 Category: Microbiology Authors: Fernández-Martínez LT, Hoskisson PA Tags: Curr Opin Microbiol Source Type: research

Unlocking the trove of metabolic treasures: activating silent biosynthetic gene clusters in bacteria and fungi.
Abstract Bacteria and fungi are prolific producers of secondary metabolites, yet they house a multitude of silent biosynthetic gene clusters that are poorly expressed and whose products are unknown or 'cryptic'. Stimulating the expression of these clusters and accessing their associated molecules is a major priority, as they are expected to have a veritable cornucopia of bioactivites. Here, we highlight three strategies that have been the focus of recent developments. Co-culture and elicitor screening, genetic regulator investigation and exploitation, and pathway refactoring and heterologous cluster expression, ar...
Source: Current Opinion in Microbiology - April 15, 2019 Category: Microbiology Authors: Zhang X, Hindra, Elliot MA Tags: Curr Opin Microbiol Source Type: research

The BvgASR virulence regulon of Bordetella pertussis.
Abstract The BvgAS two-component system of Bordetella pertussis directly activates the expression of a large number of virulence genes in an environmentally responsive manner. The Bvg+ mode also promotes the expression of the phosphodiesterase BvgR, which turns off the expression of another set of genes, the vrgs, by reducing levels of c-di-GMP. Increased levels of c-di-GMP in the Bvg- mode are required, together with the phosphorylated response regulator protein RisA∼P, to activate vrg expression. Phosphorylation of RisA requires RisK, a non-co-operonic sensor kinase, but not its co-operonic sensor kinase Ris...
Source: Current Opinion in Microbiology - March 11, 2019 Category: Microbiology Authors: Chen Q, Stibitz S Tags: Curr Opin Microbiol Source Type: research

Genome mining and prospects for antibiotic discovery.
Abstract Natural products are a rich source of bioactive compounds that have been used successfully in the areas of human health from infectious disease to cancer; however, traditional fermentation-based screening has provided diminishing returns over the last 20-30 years. Solutions to the unmet need of resistant bacterial infection are critically required. Technological advances in high-throughput genomic sequencing, coupled with ever-decreasing cost, are now presenting a unique opportunity for the reinvigoration of natural product discovery. Bioinformatic methods can predict the propensity of a microbial strain ...
Source: Current Opinion in Microbiology - February 15, 2019 Category: Microbiology Authors: Foulston L Tags: Curr Opin Microbiol Source Type: research

Vibrio variations on a type three theme.
Abstract Mounting evidence suggests that Type 3 Secretion Systems (T3SS) are widespread among Vibrio species, and are present in strains isolated from diverse sources such as human clinical infections, environmental reservoirs, and diseased marine life. Experiments evaluating Vibrio parahaemolyticus and Vibrio cholerae T3SS mediated virulence suggest that Vibrio T3SS pathogenicity islands have a tripartite composition. A conserved 'core' region encodes functions essential for colonization and disease in vivo, including modulation of innate immune signaling pathways and actin dynamics, whereas regions flanking core...
Source: Current Opinion in Microbiology - January 31, 2019 Category: Microbiology Authors: Miller KA, Tomberlin KF, Dziejman M Tags: Curr Opin Microbiol Source Type: research

Modulation of host cell metabolism by T4SS-encoding intracellular pathogens.
n A Abstract Intracellular bacterial pathogens intimately interact with the infected host cell to prevent elimination and to ensure survival. One group of intracellular pathogens, including Coxiella burnetii, Legionella pneumophila, Brucella spp., Anaplasma phagocytophilum, and Ehrlichia chaffeensis, utilizes a type IV secretion system (T4SS) that injects effectors to modulate host cell signalling, vesicular trafficking, autophagy, cell death and transcription to ensure survival [1]. So far, little emphasis has been directed towards understanding how these bacteria manipulate host cell metabolism. This manipulatio...
Source: Current Opinion in Microbiology - January 10, 2019 Category: Microbiology Authors: Hayek I, Berens C, Lührmann A Tags: Curr Opin Microbiol Source Type: research

Nutrient sulfur acquisition strategies employed by bacterial pathogens.
Abstract Pathogens have evolved elegant mechanisms to acquire essential nutrients from host environments. Sulfur is a requirement for bacterial growth and inorganic and organic sulfur-containing metabolites are abundant within the host-pathogen interface. A growing body of evidence suggests that pathogens are capable of scavenging both types of sulfur sources to fulfill the nutritional requirement. While therapeutic strategies focusing on inhibiting inorganic sulfate assimilation and cysteine synthesis show promise in vitro, in vivo efficacy maybe limited due to the diversity of host-derived sulfur sources and the...
Source: Current Opinion in Microbiology - December 7, 2018 Category: Microbiology Authors: Lensmire JM, Hammer ND Tags: Curr Opin Microbiol Source Type: research

Effective models and the search for quantitative principles in microbial evolution.
Abstract Microbes evolve rapidly. Yet they do so in idiosyncratic ways, which depend on the specific mutations that are beneficial or deleterious in a given situation. At the same time, some population-level patterns of adaptation are strikingly similar across different microbial systems, suggesting that there may also be simple, quantitative principles that unite these diverse scenarios. We review the search for simple principles in microbial evolution, ranging from the biophysical level to emergent evolutionary dynamics. A key theme has been the use of effective models, which coarse-grain over molecular and cell...
Source: Current Opinion in Microbiology - December 6, 2018 Category: Microbiology Authors: Good BH, Hallatschek O Tags: Curr Opin Microbiol Source Type: research

The role of acid stress in Salmonella pathogenesis.
Abstract After uptake by epithelial cells or engulfment by macrophages, Salmonella resides in an acidic vacuole. Salmonella senses this acidic compartment through the action of the EnvZ/OmpR two-component regulatory system. OmpR, in turn, represses the cadC/BA system, preventing neutralization of the bacterial cytoplasm. New, single cell techniques now enable us to observe that in response to acid stress, the pH is low in bacterial cells and acidification is critical for infection. Instead of recovering from acid stress, Salmonella uses acid pH as a signal to drive pathogenesis. The relevant molecular mechanisms e...
Source: Current Opinion in Microbiology - December 4, 2018 Category: Microbiology Authors: Kenney LJ Tags: Curr Opin Microbiol Source Type: research

Simple organizing principles in microbial communities.
Abstract There is a great deal of interest in discovering the principles that organize microbial communities, to better understand the structure and diversity of these communities in the natural world. Recent conceptual and technical advances have shown how simple organizing principles can give rise to surprising diversity and complex patterns in these consortia. Understanding competition, cooperation, and communication among microbes has provided novel insights into the structure and behavior of microbial collectives, and the use of simple animal models has advanced our understanding of microbial ecology in the h...
Source: Current Opinion in Microbiology - November 29, 2018 Category: Microbiology Authors: Gore J Tags: Curr Opin Microbiol Source Type: research

Control of bacterial colonization in the glands and crypts.
Abstract The epithelial cell layer of the major organs of the mammalian gastrointestinal (GI) tract is extensively invaginated into thousands of gland and crypt structures. These are lined by distinct sets of epithelial cells and may comprise discrete niches. The host maximizes the distance between the epithelial cell layer and GI-inhabiting microbes to limit inflammation, and these strategies also likely keep bacteria out of the glands and crypts. We discuss here the specific host processes that have been shown to restrict bacterial presence in the glands and crypts, specifically the immune system, acid, mucin, o...
Source: Current Opinion in Microbiology - November 28, 2018 Category: Microbiology Authors: Yang C, Ottemann KM Tags: Curr Opin Microbiol Source Type: research

Come, sweet death: targeting glycosomal protein import for antitrypanosomal drug development.
GM Abstract Glycosomes evolved as specialized system for glycolysis in trypanosomatids. These organelle rely on protein import to maintain function. A machinery of peroxin (PEX) proteins is responsible for recognition and transport of glycosomal proteins to the organelle. Disruption of PEX-based import system was expected to be a strategy against trypanosomatids. Recently, a proof of this hypothesis has been presented. Here, we review current information about trypanosomatids' glycosomal transport components as targets for new trypanocidal therapies. PMID: 30481613 [PubMed - as supplied by publisher] (Source...
Source: Current Opinion in Microbiology - November 24, 2018 Category: Microbiology Authors: Kalel VC, Mäser P, Sattler M, Erdmann R, Popowicz GM Tags: Curr Opin Microbiol Source Type: research

The role of chemotaxis during Campylobacter jejuni colonisation and pathogenesis.
Abstract Campylobacter jejuni is a ubiquitous gastrointestinal pathogen, transmitted to humans from birds and animals, where C. jejuni is part of normal intestinal flora. In C. jejuni, similar to other motile bacteria, chemotaxis pathway and the array of chemosensors sense and respond to external stimuli with unique precision and sensitivity and are considered to be critical for bacterial colonisation and pathogenicity. Disruption of any component of the signal transduction pathway consisting of receptor-CheA/CheW-CheY-flagella cascade, the signal adaptation system, and even a loss of a single chemosensory recepto...
Source: Current Opinion in Microbiology - November 23, 2018 Category: Microbiology Authors: Korolik V Tags: Curr Opin Microbiol Source Type: research

Colonization of the mammalian intestinal tract by enterococci.
Abstract Enterococci are colonizers of the mammalian gastrointestinal tract (GIT) and normally live in healthy association with their human host. However, enterococci are also major causes of healthcare-acquired infections, prompting the US Centers for Disease Control and Prevention to declare vancomycin-resistant enterococci (VRE) a serious threat to public health. Because of both intrinsic and acquired antibiotic resistance, enterococci proliferate in the GIT during antibiotic therapy, leading to dissemination and disease. The recognition that colonization of the GIT is a pre-requisite for enterococcal infection...
Source: Current Opinion in Microbiology - November 12, 2018 Category: Microbiology Authors: Banla LI, Salzman NH, Kristich CJ Tags: Curr Opin Microbiol Source Type: research

Sense and sensor ability: redox-responsive regulators in Listeria monocytogenes.
Abstract Listeria monocytogenes (Lm) is a Gram-positive bacterium that thrives in nature as a saprophyte and in the mammalian host as an intracellular pathogen. Both environments pose potential danger in the form of redox stress. In addition, endogenous reactive oxygen species (ROS) are continuously generated as by-products of aerobic metabolism. Redox stress from ROS can damage proteins, lipids, and DNA, making it highly advantageous for bacteria to evolve mechanisms to sense and detoxify ROS. This review focuses on the five redox-responsive regulators in Lm: OhrR (to sense organic hydroperoxides), PerR (peroxide...
Source: Current Opinion in Microbiology - November 6, 2018 Category: Microbiology Authors: Ruhland BR, Reniere ML Tags: Curr Opin Microbiol Source Type: research

Modulation of bacterial virulence and fitness by host glutathione.
Abstract Glutathione is a low molecular weight thiol that is important for maintaining intracellular redox homeostasis. Some bacteria are able to import exogenous glutathione as a nutritional source and to counter oxidative stress. In cytosolic pathogens Burkholderia pseudomallei and Listeria monocytogenes, host glutathione regulates bacterial virulence. In B. pseudomallei, glutathione activates the membrane-bound histidine kinase sensor VirA that leads to activation of the Type VI Secretion System. In L. monocytogenes, host glutathione leads to the binding of bacterial glutathione to the master virulence regulato...
Source: Current Opinion in Microbiology - November 2, 2018 Category: Microbiology Authors: Ku JW, Gan YH Tags: Curr Opin Microbiol Source Type: research

How to do business with lysosomes: Salmonella leads the way.
Abstract Pathogens have devised various strategies to alter the host endomembrane system towards building their replicative niche. This is aptly illustrated by Salmonella Typhimurium, whereby it remodels the host endolysosomal system to form a unique niche, also known as Salmonella-containing vacuole (SCV). Decades of research using in vitro cell-based infection studies have revealed intricate details of how Salmonella effectors target endocytic trafficking machinery of the host cell to acquire membrane and nutrients for bacterial replication. Unexpectedly, Salmonella requires host factors involved in endosome-lys...
Source: Current Opinion in Microbiology - November 1, 2018 Category: Microbiology Authors: Tuli A, Sharma M Tags: Curr Opin Microbiol Source Type: research

Emerging insights into bacterial deubiquitinases.
Abstract Bacterial pathogens utilize eukaryotic cellular systems in various ways for their own benefits. To counteract host immune responses and survive in cells, bacteria modify host signaling pathways. For this aim, they have evolved virulence secretion systems. Bacteria-encoded effector proteins delivered via these secretion systems are the key players in bacterial pathogenesis. Ubiquitination is a post-translational modification that governs eukaryotic cellular systems. Recent studies have revealed that many bacterial effector proteins target the host ubiquitin system, often acting as ubiquitin-modulating enzy...
Source: Current Opinion in Microbiology - November 1, 2018 Category: Microbiology Authors: Kubori T, Kitao T, Nagai H Tags: Curr Opin Microbiol Source Type: research

Molecular and cellular interactions defining the tropism of Plasmodium vivax for reticulocytes.
Abstract Plasmodium vivax is uniquely restricted to invading reticulocytes, the youngest of red blood cells. Parasite invasion relies on the sequential deployment of multiple parasite invasion ligands. Correct targeting of the host reticulocyte is mediated by two families of invasion ligands: the reticulocyte binding proteins (RBPs) and erythrocyte binding proteins (EBPs). The Duffy receptor has long been established as a key determinant for P. vivax invasion. However, recently, the RBP protein PvRBP2b has been shown to bind to transferrin receptor, which is expressed on reticulocytes but lost on normocytes, impli...
Source: Current Opinion in Microbiology - October 23, 2018 Category: Microbiology Authors: Kanjee U, Rangel GW, Clark MA, Duraisingh MT Tags: Curr Opin Microbiol Source Type: research

Editorial overview: Current Opinion in Microbiology 2018 Special issue 'Microbial systems biology, vol. 45'.
PMID: 30343003 [PubMed - as supplied by publisher] (Source: Current Opinion in Microbiology)
Source: Current Opinion in Microbiology - October 17, 2018 Category: Microbiology Authors: Hwa T, Sauer U Tags: Curr Opin Microbiol Source Type: research

Parasitic nematodes manipulate plant development to establish feeding sites.
Abstract Cyst and root-knot nematodes, the two economically most important groups of plant parasitic nematodes, induce neoplastic feeding sites in the roots of their host plants. The formation of feeding sites is accompanied by large-scale transcriptomic, metabolomic, and structural changes in host plants. However, the mechanisms that lead to such remarkable changes have remained poorly understood until recently. Now, genomic and genetic analyses have greatly enhanced our understanding of all aspects of plant-nematode interaction. Here, we review some of the recent advances in understanding cyst and root-knot nema...
Source: Current Opinion in Microbiology - October 13, 2018 Category: Microbiology Authors: Siddique S, Grundler FM Tags: Curr Opin Microbiol Source Type: research

Fasciola hepatica, TGF- β and host mimicry: the enemy within.
Fasciola hepatica, TGF-β and host mimicry: the enemy within. Curr Opin Microbiol. 2018 Oct 11;46:80-85 Authors: Musah-Eroje M, Flynn RJ Abstract Helminths parasites undergo developmental changes and migration within their definitive host, in addition to establishing chronic infection. Essential to this is the evasion of host immune responses; the canonical Th2 response is effective at removing parasites resident in the intestine. Conversely, helminths also promote the development of antigen-specific anergy and regulation. This often limits pathology but allows parasite survival, parasite effector...
Source: Current Opinion in Microbiology - October 11, 2018 Category: Microbiology Authors: Musah-Eroje M, Flynn RJ Tags: Curr Opin Microbiol Source Type: research

Effector variation at tandem gene arrays in tissue-dwelling coccidia: who needs antigenic variation anyway?
We describe current tools used for the identification and characterization of these loci, and review the most recent examples of how gene-expansion driven diversification can lead to novel gene functions. PMID: 30317151 [PubMed - as supplied by publisher] (Source: Current Opinion in Microbiology)
Source: Current Opinion in Microbiology - October 11, 2018 Category: Microbiology Authors: Blank ML, Boyle JP Tags: Curr Opin Microbiol Source Type: research

Rodent malaria models: insights into human disease and parasite biology.
Abstract The use of rodents as model organisms to study human disease is based on the genetic and physiological similarities between the species. Successful molecular methods to generate transgenic reporter or humanized rodents has rendered rodents as powerful tools for understanding biological processes and host-pathogen interactions relevant to humans. In malaria research, rodent models have been pivotal for the study of liver stages, syndromes arising from blood stages of infection, and malaria transmission to and from the mammalian host. Importantly, many in vivo findings are comparable to pathology observed i...
Source: Current Opinion in Microbiology - October 11, 2018 Category: Microbiology Authors: De Niz M, Heussler VT Tags: Curr Opin Microbiol Source Type: research

Opportunities for plant natural products in infection control.
Abstract The continued spread of antimicrobial resistance represents one of the most serious infectious disease threats to global health. There is consensus that a key component of addressing this threat is to replenish the waning pipeline of antimicrobials, with attention being paid to novel mechanisms of action. This includes the development of new classes of classic bacteriostatic and bactericidal antibiotics as well as antivirulence drugs, and it is especially in these areas where plant natural products demonstrate great potential. To this end, we discuss the unique characteristics of plant natural products, t...
Source: Current Opinion in Microbiology - September 12, 2018 Category: Microbiology Authors: Salam AM, Quave CL Tags: Curr Opin Microbiol Source Type: research

Microbial exposure and human health.
Abstract The human body comprises of micro-ecosystem made up of trillions of microbes (i.e. bacteria, archaea, fungi, protists and viruses). The total microbial gene content, which is referred to as the human microbiome, is fundamental to human physiology and immunity. There exists an intricate relationship between the surrounding microbial world (i.e. the environment) and the endogenous human microbiome, mediated by the immune system. Disrupting this relationship can a profound effect on human health and disease. Understanding how microbial exposure influences immune response and the feedback on endogenous microb...
Source: Current Opinion in Microbiology - September 5, 2018 Category: Microbiology Authors: Sharma A, Gilbert JA Tags: Curr Opin Microbiol Source Type: research

Editorial overview: Antimicrobials.
PMID: 30177439 [PubMed - as supplied by publisher] (Source: Current Opinion in Microbiology)
Source: Current Opinion in Microbiology - August 31, 2018 Category: Microbiology Authors: van Wezel GP, Wright GD Tags: Curr Opin Microbiol Source Type: research

Helminth extracellular vesicles in host-parasite interactions.
Abstract Extracellular vesicles (EVs) have been characterized from many species of parasitic helminths, and recent experimental evidence supports important functions for their cargo in host-parasite relationships as immunomodulatory mediators. Here we summarize available data on the effects of parasite-derived EVs, including their protein and/or small RNA contents, on their hosts. PMID: 30172862 [PubMed - as supplied by publisher] (Source: Current Opinion in Microbiology)
Source: Current Opinion in Microbiology - August 30, 2018 Category: Microbiology Authors: Tritten L, Geary TG Tags: Curr Opin Microbiol Source Type: research

From systems biology to metabolically engineered cells-an omics perspective on the development of industrial microbes.
Abstract Green routes are indispensable for a sustainable production of energy, chemicals and materials, and health and nutrition products from renewable resources. Naturally, microbes are capable to conduct many of the desired biochemical conversions involved, however, only at rather low efficiency. It is therefore essential to metabolically engineer them towards efficient cell factories, which enable a high product titer, yield and productivity, exhibit a good process robustness and a broad substrate spectrum, and are safe to be used, to name a few prominent points from the wish list for industrial bio-productio...
Source: Current Opinion in Microbiology - August 29, 2018 Category: Microbiology Authors: Becker J, Wittmann C Tags: Curr Opin Microbiol Source Type: research

Editorial overview: It's the ecology, stupid: microbiome research in the post-stamp collecting age.
PMID: 30145038 [PubMed - as supplied by publisher] (Source: Current Opinion in Microbiology)
Source: Current Opinion in Microbiology - August 22, 2018 Category: Microbiology Authors: Raes J Tags: Curr Opin Microbiol Source Type: research

The criminal association of Leishmania parasites and viruses.
Abstract In nature, humans infected with protozoan parasites can encounter viruses, which could alter their host immune response. The impact of viruses on human parasitic diseases remains largely unexplored due to the highly sterilized environment in experimental studies and the difficulty to draw a correlation between co-infection and pathology. Recent studies show that viral infections exacerbate pathology and promote dissemination of some Leishmania infections, based on a hyper-inflammatory reaction driven by type I interferons. Thus, not only the infecting parasite species, but also bystander viral infections ...
Source: Current Opinion in Microbiology - August 7, 2018 Category: Microbiology Authors: Rossi M, Fasel N Tags: Curr Opin Microbiol Source Type: research

Early life colonization of the human gut: microbes matter everywhere.
Abstract Microbes colonising the infant intestine, especially bacteria, are considered important for metabolic and immunological programming in early life, potentially affecting the susceptibility of the host to disease. We combined published data to provide a global view of microbiota development in early life. The results support the concept that the microbiota develops with age in an orchestrated manner, showing common patterns across populations. Furthermore, infants are colonised at birth by specific, selected maternal faecal bacteria and likely their bacteriophages. Therefore, infants are adapted to receivin...
Source: Current Opinion in Microbiology - August 4, 2018 Category: Microbiology Authors: Korpela K, de Vos WM Tags: Curr Opin Microbiol Source Type: research

Are microbiome studies ready for hypothesis-driven research?
ght R Abstract Hypothesis-driven research has led to many scientific advances, but hypotheses cannot be tested in isolation: rather, they require a framework of aggregated scientific knowledge to allow questions to be posed meaningfully. This framework is largely still lacking in microbiome studies, and the only way to create it is by discovery-driven, tool-driven, and standards-driven research projects. Here we illustrate these issues using several such non-hypothesis-driven projects from our own laboratories, including spatial mapping, the American Gut Project, the Earth Microbiome Project (which is an umbrella ...
Source: Current Opinion in Microbiology - July 27, 2018 Category: Microbiology Authors: Tripathi A, Marotz C, Gonzalez A, Vázquez-Baeza Y, Song SJ, Bouslimani A, McDonald D, Zhu Q, Sanders JG, Smarr L, Dorrestein PC, Knight R Tags: Curr Opin Microbiol Source Type: research

Integrating genetic and protein-protein interaction networks maps a functional wiring diagram of a cell.
Abstract Systematic experimental approaches have led to construction of comprehensive genetic and protein-protein interaction networks for the budding yeast, Saccharomyces cerevisiae. Genetic interactions capture functional relationships between genes using phenotypic readouts, while protein-protein interactions identify physical connections between gene products. These complementary, and largely non-overlapping, networks provide a global view of the functional architecture of a cell, revealing general organizing principles, many of which appear to be evolutionarily conserved. Here, we focus on insights derived fr...
Source: Current Opinion in Microbiology - July 27, 2018 Category: Microbiology Authors: VanderSluis B, Costanzo M, Billmann M, Ward HN, Myers CL, Andrews BJ, Boone C Tags: Curr Opin Microbiol Source Type: research

Standardization in host-microbiota interaction studies: challenges, gnotobiology as a tool, and perspective.
SC Abstract Considering the increasing list of diseases linked to the commensal microbiota, experimental studies of host-microbe interactions are of growing interest. Axenic and differently colonized animal models are inalienable tools to study these interactions. Factors, such as host genetics, diet, antibiotics and litter affect microbiota composition and can be confounding factors in many experimental settings. The use of gnotobiotic mice harboring defined microbiotas of different complexity plus additional housing standardization have thus become a gold standard to study the influence of the microbiome on the...
Source: Current Opinion in Microbiology - July 26, 2018 Category: Microbiology Authors: Mooser C, Gomez de Agüero M, Ganal-Vonarburg SC Tags: Curr Opin Microbiol Source Type: research

Mechanisms of biofilm stimulation by subinhibitory concentrations of antimicrobials.
Abstract Biofilms are a typical mode of growth for most microorganisms and provide them with a variety of survival benefits. Biofilms can pose medical and industrial challenges due to their increased tolerance of antimicrobials and disinfectants. Exposure of bacteria to subinhibitory concentrations of those compounds can further exacerbate the problem, as they provoke physiological changes that lead to increased biofilm production and potential therapeutic failure. The protected niche of a biofilm provides conditions that promote selection for persisters and resistant mutants. In this review we discuss our current...
Source: Current Opinion in Microbiology - July 24, 2018 Category: Microbiology Authors: Ranieri MR, Whitchurch CB, Burrows LL Tags: Curr Opin Microbiol Source Type: research

Microbial communities as dynamical systems.
Abstract Nowadays, microbial communities are frequently monitored over long periods of time and the interactions between their members are explored in vitro. This development has opened the way to apply mathematical models to characterize community structure and dynamics, to predict responses to perturbations and to explore general dynamical properties such as stability, alternative stable states and periodicity. Here, we highlight the role of dynamical systems theory in the exploration of microbial communities, with a special emphasis on the generalized Lotka-Volterra (gLV) equations. In particular, we discuss ap...
Source: Current Opinion in Microbiology - July 21, 2018 Category: Microbiology Authors: Gonze D, Coyte KZ, Lahti L, Faust K Tags: Curr Opin Microbiol Source Type: research

Low diversity gut microbiota dysbiosis: drivers, functional implications and recovery.
Abstract Dysbiosis, an imbalance in microbial communities, is linked with disease when this imbalance disturbs microbiota functions essential for maintaining health or introduces processes that promote disease. Dysbiosis in disease is predicted when microbiota differ compositionally from a healthy control population, but only truly defined when these differences are mechanistically related to adverse phenotypes. For the human gut microbiota, dysbiosis varies across diseases. One common manifestation is replacement of the complex community of anaerobes typical of the healthy adult gut microbiome with a community of...
Source: Current Opinion in Microbiology - July 20, 2018 Category: Microbiology Authors: Kriss M, Hazleton KZ, Nusbacher NM, Martin CG, Lozupone CA Tags: Curr Opin Microbiol Source Type: research

Resolving host-microbe interactions in the gut: the promise of in vitro models to complement in vivo research.
Abstract While animal models remain essential for inferring causality, they exhibit important limitations, which restrict the direct translation of findings into new approaches aimed at steering host-microbe interactions for the improvement of human health. Different in vitro models have therefore been developed which incorporate human cell types and microbiota. By virtue of their intricate designs, these models result in human and microbial read-outs reflective of in vivo gut physiology, and present important alternatives to animal models. However, to allow systematic investigations of the interactions between gu...
Source: Current Opinion in Microbiology - July 18, 2018 Category: Microbiology Authors: Paul W, Marta C, Tom VW Tags: Curr Opin Microbiol Source Type: research

A unified conceptual framework for prediction and control of microbiomes.
Abstract Microbiomes impact nearly all systems on Earth, and despite vast differences among systems, we contend that it is possible and highly beneficial to develop a unified conceptual framework for understanding microbiome dynamics that is applicable across systems. The ability to robustly predict and control environmental and human microbiomes would provide impactful opportunities to sustain and improve the health of ecosystems and humans alike. Doing so requires understanding the processes governing microbiome temporal dynamics, which currently presents an enormous challenge. We contend, however, that new oppo...
Source: Current Opinion in Microbiology - July 11, 2018 Category: Microbiology Authors: Stegen JC, Bottos EM, Jansson JK Tags: Curr Opin Microbiol Source Type: research

Repeat-containing effectors of filamentous pathogens and symbionts.
Abstract Pathogenic and symbiotic filamentous microbes secrete effectors which suppress host immune responses and promote a successful colonization. Pathogen effectors are engaged in the arms race with their hosts and because of this they are subject to intense evolutionary pressure. Effectors particularly prone to rapid evolution display repeat-containing domains which can easily expand or contract and accumulate point mutations without altering their original function. In this review we address the diversity of function in such repeat-containing effectors, focus on new findings and point out avenues for future w...
Source: Current Opinion in Microbiology - June 18, 2018 Category: Microbiology Authors: Ma LS, Pellegrin C, Kahmann R Tags: Curr Opin Microbiol Source Type: research