Spotlight
Minireview
MinireviewCytochromes in Extracellular Electron Transfer in GeobacterExtracellular electron transfer (EET) is an important biological process in microbial physiology as found in dissimilatory metal oxidation/reduction and interspecies electron transfer in syntrophy in natural environments. EET also plays a critical role in microorganisms relevant to environmental biotechnology in metal-contaminated areas, metal corrosion, bioelectrochemical systems, and anaerobic digesters. Geobacter species...
Biotechnology
BiotechnologyCranberry-Derived Proanthocyanidins Potentiate β-Lactam Antibiotics against Resistant BacteriaThe emergence of β-lactam-resistant Enterobacteriaceae and staphylococci compromised the efficiency of β-lactam-based therapy. By acquisition of ESBLs, MBLs, or PBPs, it is highly likely that bacteria may become completely resistant to the most efficient β-lactam agents in the near future.
Biotechnology | SpotlightIdentification of Fungal Limonene-3-Hydroxylase for Biotechnological Menthol Production(−)-Menthol is an important flavor and fragrance compound and furthermore has medicinal uses. To realize a two-step synthesis starting from renewable (+)-limonene, a regioselective limonene-3-hydroxylase enzyme is necessary. We identified enzymes from two different fungi which catalyze this hydroxylation reaction and represent an important module for the development of a biotechnological process for (−)-menthol production from renewable...
BiotechnologyEngineering of the Small Noncoding RNA (sRNA) DsrA Together with the sRNA Chaperone Hfq Enhances the Acid Tolerance of Escherichia coliMany of the traditional studies on bacterial acid tolerance generally focused on improving cell survival under extreme-pH conditions, but cell growth under less harsh acidic conditions is more relevant to industrial applications. Under normal conditions, the general stress response sigma factor RpoS is maintained at low levels in the growth phase through a number of mechanisms.
Environmental Microbiology
Environmental MicrobiologyBacteriophages against Vibrio coralliilyticus and Vibrio tubiashii: Isolation, Characterization, and Remediation of Larval Oyster MortalitiesShellfish hatcheries encounter episodic outbreaks of larval oyster mortalities, jeopardizing the economic stability of hatcheries and the commercial shellfish industry. Shellfish pathogens like Vibrio coralliilyticus and Vibrio tubiashii have been recognized as major contributors of larval oyster...
Environmental MicrobiologyOccurrence and Transmission of blaNDM-Carrying Enterobacteriaceae from Geese and the Surrounding Environment on a Commercial Goose FarmCarbapenem-resistant bacteria, in particular NDM-producing Enterobacteriaceae, have become a great threat to global public. These bacteria have been found not only in hospital and community environments but also among food animal production chains, which are recognized as reservoirs for NDM-producing Enterobacteriaceae.
Environmental Microbiology | SpotlightLong-Term Exposure to Octenidine in a Simulated Sink Trap Environment Results in Selection of Pseudomonas aeruginosa, Citrobacter, and Enterobacter Isolates with Mutations in Efflux Pump RegulatorsMultidrug-resistant (MDR) strains of bacteria are a major clinical problem, and several reports have linked outbreaks of MDR bacteria with bacterial populations in hospital sinks. Biocides such as octenidine are used clinically in body washes and other products, such as wound dressings for infection control.
Environmental MicrobiologyLocal Adaptation of Legionella pneumophila within a Hospital Hot Water System Increases Tolerance to CopperLegionella pneumophila is a pathogen indigenous to natural and large building water systems in the bulk and the biofilm phases. The immediate environment within a system can impact the tolerance of L. pneumophila to environmental stressors, including copper.
Environmental MicrobiologyAn Antifungal Polycyclic Tetramate Macrolactam, Heat-Stable Antifungal Factor (HSAF), Is a Novel Oxidative Stress Modulator in Lysobacter enzymogenesPoTeMs are a family of structurally distinct metabolites that have been found in a large number of bacteria. Although PoTeMs exhibit diverse therapeutic properties, the physiological function of PoTeMs in the producer microorganisms had not been investigated.
Environmental MicrobiologyIdentification of an Intermediate Form of Ferredoxin That Binds Only Iron Suggests That Conversion to Holo-Ferredoxin Is Independent of the ISC System in Escherichia coliFdx is an electron carrier that is required for the maturation of many other iron-sulfur proteins. Its function strictly depends on its [2Fe-2S] center that bonds with the cysteinyl S atoms of four cysteine residues within Fdx.
Environmental MicrobiologyIdentification and Predictions Regarding the Biosynthesis Pathway of Polyene Macrolides Produced by Streptomyces roseoflavus Men-myco-93-63Streptomyces roseoflavus Men-myco-93-63 is a biocontrol strain that has been studied in our laboratory for many years and exhibits a good inhibitory effect in many crop diseases. Therefore, the identification of antimicrobial metabolites is necessary and our main objective.
Environmental MicrobiologyEffective Antibacterial and Antihemolysin Activities of Ellipticine Hydrochloride against Streptococcus suis in a Mouse ModelIn recent years, the inappropriate use of antibiotics has unnecessarily caused the continuous emergence of resistant bacteria. The antimicrobial resistance of Streptococcus suis has also become an increasingly serious problem.
Enzymology and Protein Engineering
Enzymology and Protein EngineeringNovel 3-O-α-d-Galactosyl-α-l-Arabinofuranosidase for the Assimilation of Gum Arabic Arabinogalactan Protein in Bifidobacterium longum subsp. longumBifidobacteria harbor numerous carbohydrate-active enzymes that degrade several dietary fibers in the gastrointestinal tract. B. longum JCM7052 is known to exhibit the ability to assimilate gum arabic AGP, but the key enzyme involved in the degradation of gum arabic AGP remains unidentified. Here, we cloned and characterized a GH39 3-O-α-d...
Food Microbiology
Food MicrobiologyDistribution of ε-Poly-l-Lysine Synthetases in Coryneform Bacteria Isolated from Cheese and Human SkinEvery year, microbial contamination causes billions of tons of food wasted and millions of cases of illness. ε-Poly-l-lysine has potent, wide-spectrum inhibitory activity and is heat stable and biodegradable. It has been approved for food preservation by an increasing number of countries. ε-Poly-l-lysine is produced from soil bacteria of the genus Streptomyces, also producers of...
Food MicrobiologyBiofilm Formation by Listeria monocytogenes 15G01, a Persistent Isolate from a Seafood-Processing Plant, Is Influenced by Inactivation of Multiple Genes Belonging to Different Functional GroupsThe major source of contamination of food with Listeria monocytogenes is thought to be due to biofilm formation and/or persistence in food-processing plants. By establishing as a biofilm, L. monocytogenes cells become harder to eradicate due to their increased resistance to environmental threats....
Food MicrobiologyManure-Based Amendments Influence Surface-Associated Bacteria and Markers of Antibiotic Resistance on Radishes Grown in Soils with Different TexturesIn working toward a comprehensive strategy to combat the spread of antibiotic resistance, potential farm-to-fork routes of dissemination are gaining attention. The effects of preharvest factors on the microbiota and corresponding antibiotic resistance indicators on the surfaces of produce commonly eaten raw is of special interest.
Genetics and Molecular Biology
Genetics and Molecular BiologyNatural Transformation in a Classical-Biotype Vibrio cholerae StrainNatural transformation (uptake of exogenous DNA) in Vibrio cholerae has contributed to the evolution of these human pathogens. Classical biotype V. cholerae strains were responsible for the first six cholera pandemics but were replaced by El Tor biotype...
Genetics and Molecular Biology | SpotlightCalcium-Regulated Protein CarP Responds to Multiple Host Signals and Mediates Regulation of Pseudomonas aeruginosa Virulence by CalciumP. aeruginosa is a human pathogen causing life-threatening infections. It is particularly notorious for its ability to adapt to diverse environments within the host.
Genetics and Molecular Biology | SpotlightImproving Acetic Acid and Furfural Resistance of Xylose-Fermenting Saccharomyces cerevisiae Strains by Regulating Novel Transcription Factors Revealed via Comparative Transcriptomic AnalysisInhibitor tolerance is essential for S. cerevisiae when fermenting lignocellulosic hydrolysate with various inhibitors, including weak acids, furans, and phenols. The details regarding how xylose-fermenting S. cerevisiae strains respond to multiple inhibitors during fermenting mixed glucose and...
Genetics and Molecular BiologyGeneration of Genetic Tools for Gauging Multiple-Gene Expression at the Single-Cell LevelWithin a bacterial population, single cells can differently express some genes, even though they are genetically identical and experience the same chemical and physical stimuli. This phenomenon, known as phenotypic heterogeneity, is mainly driven by gene expression noise and results in the emergence of bacterial subpopulations with distinct phenotypes.
Invertebrate Microbiology
Invertebrate MicrobiologyMacrobdella decora: Old World Leech Gut Microbial Community Structure Conserved in a New World LeechBuilding evidence implicates the gut microbiome in critical animal functions such as regulating digestion, nutrition, immune regulation, and development. Simplified, phylogenetically diverse models for hypotheses testing are necessary because of the difficulty of assigning causative relationships in complex gut microbiomes.
Microbial Ecology
Microbial EcologyThe Nutritional Significance of Intestinal Fungi: Alteration of Dietary Carbohydrate Composition Triggers Colonic Fungal Community Shifts in a Pig ModelAlthough fungi are a large group of microorganisms along with bacteria and archaea in the gut of monogastric animals, the nutritional significance of fungi has been ignored for a long time. Our previous studies revealed a distinct fungal community in the gut of grazing Tibetan pigs (1) and a close correlation between fungal species and short-chain fatty acids, the main microbial...
Microbial Ecology | SpotlightBiogenic Amines Increase the Odds of Bacterial Vaginosis and Affect the Growth of and Lactic Acid Production by Vaginal Lactobacillus spp.Lactobacillus spp. are credited with providing the primary defense against gynecological conditions, including BV, most notably through the acidification of the vaginal microenvironment, which results from their production of lactic acid. The microbial production of BAs has been hypothesized to play a mechanistic role in diminishing Lactobacillus species-mediated protection, enabling the colonization and outgrowth of...
Plant Microbiology
Plant MicrobiologyHyperlocal Variation in Soil Iron and the Rhizosphere Bacterial Community Determines Dollar Spot Development in Amenity TurfgrassDollar spot is the most economically important disease of amenity turfgrass, and more fungicides are applied targeting dollar spot than any other turfgrass disease. Dollar spot symptoms are small (3 to 5 cm), circular patches that develop in a highly variable manner within plot scale even under seemingly uniform conditions.
Plant MicrobiologySoybean Root Nodule and Rhizosphere Microbiome: Distribution of Rhizobial and Nonrhizobial EndophytesSoybean (Glycine max L.) is a valuable food crop that also contributes significantly to soil nitrogen by developing a symbiotic association with nitrogen-fixing rhizobia. Bacterial endophytes (both rhizobial and nonrhizobial) are considered critical for the growth and resilience of the legume host.
Public and Environmental Health Microbiology
Public and Environmental Health MicrobiologyDetection of Rotavirus Vaccine Strains in Oysters and Sewage and Their Relationship with the Gastroenteritis EpidemicWe quantified rotavirus A (RVA), Rotarix, and RotaTeq strains in oyster and sewage samples during two gastroenteritis seasons and revealed the exact contamination of wild-type RVA by subtracting the quantitative value of rotavirus vaccine strains from that of RVA. The concentration of wild-type RVA was significantly correlated between oysters and sewage, although no significant correlation was seen between wild-type RVA concentration in...
Public and Environmental Health MicrobiologyAntimicrobial Resistance in Porcine Enterococci in Australia and the Ramifications for Human HealthResistance to the critically important antimicrobials vancomycin, teicoplanin, and linezolid is not found in enterococci collected from Australian finisher pigs. However, some antimicrobial resistance was observed.
Public and Environmental Health MicrobiologyPrevalence and Epidemiology of Non-O157 Escherichia coli Serogroups O26, O103, O111, and O145 and Shiga Toxin Gene Carriage in Scottish Cattle, 2014–2015Cattle are reservoirs for Shiga toxin Escherichia coli (STEC), bacteria shed in animal feces. Humans are infected through consumption of contaminated food or water and by direct contact, causing serious disease and kidney failure in the most vulnerable.
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Applied and Environmental Microbiology® (AEM) publishes study results that make significant contributions to applied microbial research, basic microbial ecology research, and genetic and molecular investigations of microbial topics of practical value.
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