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Annals of Botany Jun 2018Flowers can be highly variable in nectar volume and chemical composition, even within the same plant, but the causes of this variation are not fully understood. One...
BACKGROUND AND AIMS
Flowers can be highly variable in nectar volume and chemical composition, even within the same plant, but the causes of this variation are not fully understood. One potential cause is nectar-colonizing bacteria and yeasts, but experimental tests isolating their effects on wildflowers are largely lacking. This study examines the effects of dominant species of yeasts and bacteria on the hummingbird-pollinated shrub, Mimulus aurantiacus, in California.
METHODS
Wildflowers were inoculated with field-relevant titres of either the yeast Metschnikowia reukaufii or the bacterium Neokomagataea sp. (formerly Gluconobacter sp.), both isolated from M. aurantiacus nectar. Newly opened flowers were bagged, inoculated, harvested after 3 d and analysed for microbial abundance, nectar volume, and sugar and amino acid concentration and composition.
KEY RESULTS
Yeast inoculation reduced amino acid concentration and altered amino acid composition, but had no significant effect on nectar volume or sugar composition. In contrast, bacterial inoculation increased amino acid concentration, enhanced the proportion of nectar sugars comprised by monosaccharides, and reduced nectar volume.
CONCLUSIONS
The results presented suggest that microbial inhabitants of floral nectar can make nectar characteristics variable among flowers through divergent effects of yeasts and bacteria on nectar chemistry and availability, probably modifying plant-pollinator interactions.
Topics: Amino Acids; Flowers; Gluconobacter; Metschnikowia; Mimulus; Plant Nectar; Sugars
PubMed: 29562323
DOI: 10.1093/aob/mcy032 -
Microbial Ecology Jan 2019Plant litter decomposition is a process enabling biogeochemical cycles closing in ecosystems, and decomposition in forests constitutes the largest part of this process...
Plant litter decomposition is a process enabling biogeochemical cycles closing in ecosystems, and decomposition in forests constitutes the largest part of this process taking place in terrestrial biomes. Microbial communities during litter decomposition were studied mainly with low-throughput techniques not allowing detailed insight, particularly into coniferous litter, as it is more difficult to obtain high quality DNA required for analyses. Motivated by these problems, we analyzed archaeal, bacterial, and eukaryotic communities at three decomposition stages: fresh, 3- and 8-month-old litter by 16/18S rDNA pyrosequencing, aiming at detailed insight into early stages of pine litter decomposition. Archaea were absent from our libraries. Bacterial and eukaryotic diversity was greatest in 8-month-old litter and the same applied to bacterial and fungal rDNA content. Community structure was different at various stages of decomposition, and phyllospheric organisms (bacteria: Acetobacteraceae and Pseudomonadaceae members, fungi: Lophodermium, Phoma) were replaced by communities with metabolic capabilities adapted to the particular stage of decomposition. Sphingomonadaceae and Xanthomonadaceae and fungal genera Sistotrema, Ceuthospora, and Athelia were characteristic for 3-month-old samples, while 8-month-old ones were characterized by Bradyrhizobiaceae and nematodes (Plectus). We suggest that bacterial and eukaryotic decomposer communities change at different stages of pine litter decomposition in a way similar to that in broadleaf litter. Interactions between bacteria and eukaryotes appear to be one of the key drivers of microbial community structure.
Topics: Archaea; Bacteria; Biodiversity; DNA; DNA, Ribosomal; Decompression; Ecosystem; Eukaryota; Fungi; Metagenomics; Microbiota; Pinus; RNA, Ribosomal, 16S; RNA, Ribosomal, 18S; Soil Microbiology; Trees
PubMed: 29850933
DOI: 10.1007/s00248-018-1209-x -
Science Advances Dec 2017Despite recent advances to control the spatial composition and dynamic functionalities of bacteria embedded in materials, bacterial localization into complex...
Despite recent advances to control the spatial composition and dynamic functionalities of bacteria embedded in materials, bacterial localization into complex three-dimensional (3D) geometries remains a major challenge. We demonstrate a 3D printing approach to create bacteria-derived functional materials by combining the natural diverse metabolism of bacteria with the shape design freedom of additive manufacturing. To achieve this, we embedded bacteria in a biocompatible and functionalized 3D printing ink and printed two types of "living materials" capable of degrading pollutants and of producing medically relevant bacterial cellulose. With this versatile bacteria-printing platform, complex materials displaying spatially specific compositions, geometry, and properties not accessed by standard technologies can be assembled from bottom up for new biotechnological and biomedical applications.
Topics: Bacillus subtilis; Bacteria; Biocompatible Materials; Biodegradation, Environmental; Cells, Immobilized; Cellulose; Gluconacetobacter xylinus; Hydrogels; Phenols; Printing, Three-Dimensional; Pseudomonas putida; Rheology; Ultraviolet Rays
PubMed: 29214219
DOI: 10.1126/sciadv.aao6804 -
PeerJ 2019Microorganisms play a central role in the biology of vinegar flies such as and : serving as a food source to both adults and larvae, and influencing a range of traits...
Microorganisms play a central role in the biology of vinegar flies such as and : serving as a food source to both adults and larvae, and influencing a range of traits including nutrition, behavior, and development. The niches utilized by the fly species partially overlap, as do the microbiota that sustain them, and interactions among these players may drive the development of crop diseases. To learn more about how the microbiota of one species may affect the other, we isolated and identified microbes from field-caught , and then characterized their effects on larval development time in the laboratory. We found that the microbiota consistently included both yeasts and bacteria. It was dominated by yeasts of the genus , and bacteria from the families Acetobacteraceae and Enterobacteriaceae. Raising under gnotobiotic conditions with each microbial isolate individually, we found that some bacteria promoted larval development relative to axenic conditions, but most did not have a significant effect. In contrast, nearly all the yeasts tested significantly accelerated larval development. The one exception was , which had the opposite effect: significantly slowing larval developmental rate. We investigated the basis for this effect by examining whether cells could sustain larval growth, and measuring the survival of and other yeasts in the larval gut. Our results suggest is not digested by and therefore cannot serve as a source of nutrition. These findings have interesting implications for possible interactions between the two species and their microbiota in nature. Overall, we found that microbes isolated from promote larval development, which is consistent with the model that infestation of fruit by can open up habitat for . We propose that the microbiome is an important dimension of the ecological interactions between species.
PubMed: 31763075
DOI: 10.7717/peerj.8097 -
PLoS Neglected Tropical Diseases Feb 2023Opisthorchis felineus, Opisthorchis viverrini and Clonorchis sinensis are epidemiologically significant food-borne trematodes endemic to diverse climatic areas. O....
BACKGROUND
Opisthorchis felineus, Opisthorchis viverrini and Clonorchis sinensis are epidemiologically significant food-borne trematodes endemic to diverse climatic areas. O. viverrini and C. sinensis are both recognized to be 1A group of biological carcinogens to human, whereas O. felineus is not. The mechanisms of carcinogenesis by the liver flukes are studied fragmentarily, the role of host and parasite microbiome is an unexplored aspect.
METHODOLOGY/PRINCIPAL FINDINGS
Specific pathogen free Mesocricetus auratus hamsters were infected with C. sinensis, O. viverrini and O. felineus. The microbiota of the adult worms, colon feces and bile from the hamsters was investigated using Illumina-based sequencing targeting the prokaryotic 16S rRNA gene. The analysis of 43 libraries revealed 18,830,015 sequences, the bacterial super-kingdom, 16 different phyla, 39 classes, 63 orders, 107 families, 187 genera-level phylotypes. O. viverrini, a fluke with the most pronounced carcinogenic potential, has the strongest impact on the host bile microbiome, changing the abundance of 92 features, including Bifidobacteriaceae, Erysipelotrichaceae, [Paraprevotellaceae], Acetobacteraceae, Coriobacteraceae and Corynebacteriaceae bacterial species. All three infections significantly increased Enterobacteriaceae abundance in host bile, reduced the level of commensal bacteria in the gut microbiome (Parabacteroides, Roseburia, and AF12).
CONCLUSIONS/SIGNIFICANCE
O. felineus, O. viverrini, and C. sinensis infections cause both general and species-specific qualitative and quantitative changes in the composition of microbiota of bile and colon feces of experimental animals infected with these trematodes. The alterations primarily concern the abundance of individual features and the phylogenetic diversity of microbiomes of infected hamsters.
Topics: Humans; Cricetinae; Animals; Opisthorchis; Clonorchis sinensis; Fasciola hepatica; Opisthorchiasis; Phylogeny; RNA, Ribosomal, 16S; Mesocricetus; Fascioliasis; Microbiota
PubMed: 36780567
DOI: 10.1371/journal.pntd.0011111 -
MicrobiologyOpen May 2019Komagataeibacter species are well-recognized bionanocellulose (BNC) producers. This bacterial genus, formerly assigned to Gluconacetobacter, is known for its phenotypic...
Komagataeibacter species are well-recognized bionanocellulose (BNC) producers. This bacterial genus, formerly assigned to Gluconacetobacter, is known for its phenotypic diversity manifested by strain-dependent carbon source preference, BNC production rate, pellicle structure, and strain stability. Here, we performed a comparative study of nineteen Komagataeibacter genomes, three of which were newly contributed in this work. We defined the core genome of the genus, clarified phylogenetic relationships among strains, and provided genetic evidence for the distinction between the two major clades, the K. xylinus and the K. hansenii. We found genomic traits, which likely contribute to the phenotypic diversity between the Komagataeibacter strains. These features include genome flexibility, carbohydrate uptake and regulation of its metabolism, exopolysaccharides synthesis, and the c-di-GMP signaling network. In addition, this work provides a comprehensive functional annotation of carbohydrate metabolism pathways, such as those related to glucose, glycerol, acetan, levan, and cellulose. Findings of this multi-genomic study expand understanding of the genetic variation within the Komagataeibacter genus and facilitate exploiting of its full potential for bionanocellulose production at the industrial scale.
Topics: Acetobacteraceae; Cellulose; Genes, Bacterial; Genetic Variation; Genome, Bacterial; Genomics; Nanoparticles; Phylogeny; Synteny
PubMed: 30365246
DOI: 10.1002/mbo3.731 -
Applied Microbiology and Biotechnology Mar 2021There is an increasing public awareness about the danger of dietary sugars with respect to their caloric contribution to the diet and the rise of overweight throughout...
There is an increasing public awareness about the danger of dietary sugars with respect to their caloric contribution to the diet and the rise of overweight throughout the world. Therefore, low-calorie sugar substitutes are of high interest to replace sugar in foods and beverages. A promising alternative to natural sugars and artificial sweeteners is the fructose derivative 5-keto-D-fructose (5-KF), which is produced by several Gluconobacter species. A prerequisite before 5-KF can be used as a sweetener is to test whether the compound is degradable by microorganisms and whether it is metabolized by the human microbiota. We identified different environmental bacteria (Tatumella morbirosei, Gluconobacter japonicus LMG 26773, Gluconobacter japonicus LMG 1281, and Clostridium pasteurianum) that were able to grow with 5-KF as a substrate. Furthermore, Gluconobacter oxydans 621H could use 5-KF as a carbon and energy source in the stationary growth phase. The enzymes involved in the utilization of 5-KF were heterologously overproduced in Escherichia coli, purified and characterized. The enzymes were referred to as 5-KF reductases and belong to three unrelated enzymatic classes with highly different amino acid sequences, activities, and structural properties. Furthermore, we could show that 15 members of the most common and abundant intestinal bacteria cannot degrade 5-KF, indicating that this sugar derivative is not a suitable growth substrate for prokaryotes in the human intestine. KEY POINTS: • Some environmental bacteria are able to use 5-KF as an energy and carbon source. • Four 5-KF reductases were identified, belonging to three different protein families. • Many gut bacteria cannot degrade 5-KF.
Topics: Bacteria; Clostridium; Fructose; Gammaproteobacteria; Gluconobacter; Humans; Sweetening Agents
PubMed: 33616697
DOI: 10.1007/s00253-021-11168-3 -
Viruses May 2023The mosquito microbiota impacts different parameters in host biology, such as development, metabolism, immune response and vector competence to pathogens. As the...
BACKGROUND
The mosquito microbiota impacts different parameters in host biology, such as development, metabolism, immune response and vector competence to pathogens. As the environment is an important source of acquisition of host associate microbes, we described the microbiota and the vector competence to Zika virus (ZIKV) of from three areas with distinct landscapes.
METHODS
Adult females were collected during two different seasons, while eggs were used to rear F1 colonies. Midgut bacterial communities were described in field and F1 mosquitoes as well as in insects from a laboratory colony (>30 generations, LAB) using 16S rRNA gene sequencing. F1 mosquitoes were infected with ZIKV to determine virus infection rates (IRs) and dissemination rates (DRs). Collection season significantly affected the bacterial microbiota diversity and composition, e.g., diversity levels decreased from the wet to the dry season. Field-collected and LAB mosquitoes' microbiota had similar diversity levels, which were higher compared to F1 mosquitoes. However, the gut microbiota composition of field mosquitoes was distinct from that of laboratory-reared mosquitoes (LAB and F1), regardless of the collection season and location. A possible negative correlation was detected between Acetobacteraceae and , with the former dominating the gut microbiota of F1 , while the latter was absent/undetectable. Furthermore, we detected significant differences in infection and dissemination rates (but not in the viral load) between the mosquito populations, but it does not seem to be related to gut microbiota composition, as it was similar between F1 mosquitoes regardless of their population.
CONCLUSIONS
Our results indicate that the environment and the collection season play a significant role in shaping mosquitoes' bacterial microbiota.
Topics: Animals; Female; Aedes; Zika Virus; Gastrointestinal Microbiome; Zika Virus Infection; Brazil; RNA, Ribosomal, 16S; Mosquito Vectors; Bacteria
PubMed: 37376609
DOI: 10.3390/v15061309 -
MBio Jun 2021Fungal pathogens, among other stressors, negatively impact the productivity and population size of honey bees, one of our most important pollinators (1, 2), in...
Fungal pathogens, among other stressors, negatively impact the productivity and population size of honey bees, one of our most important pollinators (1, 2), in particular their brood (larvae and pupae) (3, 4). Understanding the factors that influence disease incidence and prevalence in brood may help us improve colony health and productivity. Here, we examined the capacity of a honey bee-associated bacterium, Bombella apis, to suppress the growth of fungal pathogens and ultimately protect bee brood from infection. Our results showed that strains of inhibit the growth of two insect fungal pathogens, Beauveria bassiana and Aspergillus flavus, . This phenotype was recapitulated ; bee broods supplemented with were significantly less likely to be infected by A. flavus. Additionally, the presence of reduced sporulation of A. flavus in the few bees that were infected. Analyses of biosynthetic gene clusters across strains suggest antifungal candidates, including a type 1 polyketide, terpene, and aryl polyene. Secreted metabolites from alone were sufficient to suppress fungal growth, supporting the hypothesis that fungal inhibition is mediated by an antifungal metabolite. Together, these data suggest that can suppress fungal infections in bee brood via secretion of an antifungal metabolite. Fungi can play critical roles in host microbiomes (5-7), yet bacterial-fungal interactions are understudied. For insects, fungi are the leading cause of disease (5, 8). In particular, populations of the European honey bee (Apis mellifera), an agriculturally and economically critical species, have declined in part due to fungal pathogens. The presence and prevalence of fungal pathogens in honey bees have far-reaching consequences, endangering other species and threatening food security (1, 2, 9). Our research highlights how a bacterial symbiont protects bee brood from fungal infection. Further mechanistic work could lead to the development of new antifungal treatments.
Topics: Acetobacteraceae; Animals; Bees; Fungi; Host Microbial Interactions; Larva; Microbial Interactions; Mycoses; Symbiosis
PubMed: 34101488
DOI: 10.1128/mBio.00503-21 -
Applied Microbiology and Biotechnology May 2021Acetic acid bacteria (AAB) are valuable biocatalysts for which there is growing interest in understanding their basics including physiology and biochemistry. This is... (Review)
Review
Acetic acid bacteria (AAB) are valuable biocatalysts for which there is growing interest in understanding their basics including physiology and biochemistry. This is accompanied by growing demands for metabolic engineering of AAB to take advantage of their properties and to improve their biomanufacturing efficiencies. Controlled expression of target genes is key to fundamental and applied microbiological research. In order to get an overview of expression systems and their applications in AAB, we carried out a comprehensive literature search using the Web of Science Core Collection database. The Acetobacteraceae family currently comprises 49 genera. We found overall 6097 publications related to one or more AAB genera since 1973, when the first successful recombinant DNA experiments in Escherichia coli have been published. The use of plasmids in AAB began in 1985 and till today was reported for only nine out of the 49 AAB genera currently described. We found at least five major expression plasmid lineages and a multitude of further expression plasmids, almost all enabling only constitutive target gene expression. Only recently, two regulatable expression systems became available for AAB, an N-acyl homoserine lactone (AHL)-inducible system for Komagataeibacter rhaeticus and an L-arabinose-inducible system for Gluconobacter oxydans. Thus, after 35 years of constitutive target gene expression in AAB, we now have the first regulatable expression systems for AAB in hand and further regulatable expression systems for AAB can be expected. KEY POINTS: • Literature search revealed developments and usage of expression systems in AAB. • Only recently 2 regulatable plasmid systems became available for only 2 AAB genera. • Further regulatable expression systems for AAB are in sight.
Topics: Acetic Acid; Acetobacteraceae; Gene Expression; Metabolic Engineering
PubMed: 33856535
DOI: 10.1007/s00253-021-11269-z