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Infection and Immunity Jun 2017is a Gram-negative bacterium that infects patients with chronic granulomatous disease (CGD), a primary immunodeficiency marked by a defect in NOX2, the phagocyte NADPH...
is a Gram-negative bacterium that infects patients with chronic granulomatous disease (CGD), a primary immunodeficiency marked by a defect in NOX2, the phagocyte NADPH oxidase. Previous studies have shown that NOX2 is essential for killing of by neutrophils and monocytes and that the bacteriostatic activity of monocyte-derived macrophages (MDM) requires NOX2 and gamma interferon (IFN-γ) pretreatment. To determine whether evades phagolysosomal killing, a host defense pathway intact in both normal and CGD MDM, or whether it occupies a distinct intracellular niche in CGD MDM, we assessed the trafficking patterns of this organism. We observed colocalization of with an early endosome antigen 1 (EEA1)-positive compartment, followed by colocalization with lysosome-associated membrane protein 1 (LAMP1)-positive and LysoTracker-positive late phagosomes; these characteristics were similar in both normal and CGD MDM. Despite localization to acidified late phagosomes, viable cells were recovered from viable MDM in numbers greater than in the initial input up to 6 days after infection. remains, and in some cases appears to divide, within a membrane-bound compartment for the entire 6-day time course. These findings indicate that this organism resists both oxygen-dependent and oxygen-independent phagolysosomal antimicrobial systems of human macrophages.
Topics: Acetobacteraceae; Gram-Negative Bacterial Infections; Granulomatous Disease, Chronic; Humans; Interferon-gamma; Lysosomal Membrane Proteins; Macrophages; Membrane Glycoproteins; Microscopy, Electron, Transmission; Monocytes; NADPH Oxidase 2; NADPH Oxidases; Neutrophils; Phagocytosis; Phagosomes; Vesicular Transport Proteins
PubMed: 28320834
DOI: 10.1128/IAI.00847-16 -
PLoS Biology Apr 2017Choosing the right nutrients to consume is essential to health and wellbeing across species. However, the factors that influence these decisions are poorly understood.... (Comparative Study)
Comparative Study
Choosing the right nutrients to consume is essential to health and wellbeing across species. However, the factors that influence these decisions are poorly understood. This is particularly true for dietary proteins, which are important determinants of lifespan and reproduction. We show that in Drosophila melanogaster, essential amino acids (eAAs) and the concerted action of the commensal bacteria Acetobacter pomorum and Lactobacilli are critical modulators of food choice. Using a chemically defined diet, we show that the absence of any single eAA from the diet is sufficient to elicit specific appetites for amino acid (AA)-rich food. Furthermore, commensal bacteria buffer the animal from the lack of dietary eAAs: both increased yeast appetite and decreased reproduction induced by eAA deprivation are rescued by the presence of commensals. Surprisingly, these effects do not seem to be due to changes in AA titers, suggesting that gut bacteria act through a different mechanism to change behavior and reproduction. Thus, eAAs and commensal bacteria are potent modulators of feeding decisions and reproductive output. This demonstrates how the interaction of specific nutrients with the microbiome can shape behavioral decisions and life history traits.
Topics: Acetobacter; Acetobacteraceae; Amino Acids, Essential; Animals; Animals, Genetically Modified; Appetite Regulation; Behavior, Animal; Complex Mixtures; Drosophila Proteins; Drosophila melanogaster; Enterococcus faecalis; Feeding Behavior; Female; Food Preferences; Gastrointestinal Microbiome; Gene Knockout Techniques; Host-Parasite Interactions; Lactobacillus; Oviposition; Species Specificity; Symbiosis; Yeast, Dried
PubMed: 28441450
DOI: 10.1371/journal.pbio.2000862 -
Biosensors Dec 2023Biosensors based on an oxygen electrode, a mediator electrode, and a mediator microbial biofuel cell (MFC) using the bacteria B-1280 were formed and tested to determine...
Biosensors based on an oxygen electrode, a mediator electrode, and a mediator microbial biofuel cell (MFC) using the bacteria B-1280 were formed and tested to determine the integral toxicity. bacteria exhibited high sensitivity to the toxic effects of phenol, 2,4-dinitrophenol, salicylic and trichloroacetic acid, and a number of heavy metal ions. The system " bacteria-ferrocene-graphite-paste electrode" was superior in sensitivity to biosensors formed using an oxygen electrode and MFC, in particular regarding heavy metal ions (EC of Cr, Mn and Cd was 0.8 mg/dm, 0.3 mg/dm and 1.6 mg/dm, respectively). It was determined that the period of stable functioning of electrochemical systems during measurements was reduced by half (from 30 to 15 days) due to changes in the enzyme system of microbial cells when exposed to toxicants. Samples of the products made from polymeric materials were analyzed using developed biosensor systems and standard biotesting methods based on inhibiting the growth of duckweed , reducing the motility of bull sperm, and quenching the luminescence of the commercial test system "Ecolum". The developed bioelectrocatalytic systems were comparable in sensitivity to commercial biosensors, which made it possible to correlate the results and identify, by all methods, a highly toxic sample containing diphenylmethane-4,4'-diisocyanate according to GC-MS data.
Topics: Male; Animals; Cattle; Polymers; Semen; Metals, Heavy; Biosensing Techniques; Gluconobacter oxydans; Ions; Oxygen
PubMed: 38131771
DOI: 10.3390/bios13121011 -
BMC Biotechnology Aug 2020Cellulose, the most versatile biomolecule on earth, is available in large quantities from plants. However, cellulose in plants is accompanied by other polymers like...
BACKGROUND
Cellulose, the most versatile biomolecule on earth, is available in large quantities from plants. However, cellulose in plants is accompanied by other polymers like hemicellulose, lignin, and pectin. On the other hand, pure cellulose can be produced by some microorganisms, with the most active producer being Acetobacter xylinum. A. senengalensis is a gram-negative, obligate aerobic, motile coccus, isolated from Mango fruits in Senegal, capable of utilizing a variety of sugars and produce cellulose. Besides, the production is also influenced by other culture conditions. Previously, we isolated and identified A. senengalensis MA1, and characterized the bacterial cellulose (BC) produced.
RESULTS
The maximum cellulose production by A. senengalensis MA1 was pre-optimized for different parameters like carbon, nitrogen, precursor, polymer additive, pH, temperature, inoculum concentration, and incubation time. Further, the pre-optimized parameters were pooled, and the best combination was analyzed by using Central Composite Design (CCD) of Response Surface Methodology (RSM). Maximum BC production was achieved with glycerol, yeast extract, and PEG 6000 as the best carbon and nitrogen sources, and polymer additive, respectively, at 4.5 pH and an incubation temperature of 33.5 °C. Around 20% of inoculum concentration gave a high yield after 30 days of inoculation. The interactions between culture conditions optimized by CCD included alterations in the composition of the HS medium with 50 mL L of glycerol, 7.50 g L of yeast extract at pH 6.0 by incubating at a temperature of 33.5 °C along with 7.76 g L of PEG 6000. This gave a BC yield of wet weight as 469.83 g L.
CONCLUSION
The optimized conditions of growth medium resulted in enhanced production of bacterial cellulose by A. senegalensis MA1, which is around 20 times higher than that produced using an unoptimized HS medium. Further, the cellulose produced can be used in food and pharmaceuticals, for producing high-quality paper, wound dressing material, and nanocomposite films for food packaging.
Topics: Acetobacter; Carbon; Cell Culture Techniques; Cellulose; Culture Media; Gluconacetobacter xylinus; Glycerol; Hydrogen-Ion Concentration; Nitrogen; Temperature
PubMed: 32843009
DOI: 10.1186/s12896-020-00639-6 -
Microbial Cell Factories Oct 2016Acetic acid bacteria (AAB) are well known producers of commercially used exopolysaccharides, such as cellulose and levan. Kozakia (K.) baliensis is a relatively new...
BACKGROUND
Acetic acid bacteria (AAB) are well known producers of commercially used exopolysaccharides, such as cellulose and levan. Kozakia (K.) baliensis is a relatively new member of AAB, which produces ultra-high molecular weight levan from sucrose. Throughout cultivation of two K. baliensis strains (DSM 14400, NBRC 16680) on sucrose-deficient media, we found that both strains still produce high amounts of mucous, water-soluble substances from mannitol and glycerol as (main) carbon sources. This indicated that both Kozakia strains additionally produce new classes of so far not characterized EPS.
RESULTS
By whole genome sequencing of both strains, circularized genomes could be established and typical EPS forming clusters were identified. As expected, complete ORFs coding for levansucrases could be detected in both Kozakia strains. In K. baliensis DSM 14400 plasmid encoded cellulose synthase genes and fragments of truncated levansucrase operons could be assigned in contrast to K. baliensis NBRC 16680. Additionally, both K. baliensis strains harbor identical gum-like clusters, which are related to the well characterized gum cluster coding for xanthan synthesis in Xanthomanas campestris and show highest similarity with gum-like heteropolysaccharide (HePS) clusters from other acetic acid bacteria such as Gluconacetobacter diazotrophicus and Komagataeibacter xylinus. A mutant strain of K. baliensis NBRC 16680 lacking EPS production on sucrose-deficient media exhibited a transposon insertion in front of the gumD gene of its gum-like cluster in contrast to the wildtype strain, which indicated the essential role of gumD and of the associated gum genes for production of these new EPS. The EPS secreted by K. baliensis are composed of glucose, galactose and mannose, respectively, which is in agreement with the predicted sugar monomer composition derived from in silico genome analysis of the respective gum-like clusters.
CONCLUSIONS
By comparative sugar monomer and genome analysis, the polymeric substances secreted by K. baliensis can be considered as unique HePS. Via genome sequencing of K. baliensis DSM 14400 + NBRC 16680 we got first insights into the biosynthesis of these novel HePS, which is related to xanthan and acetan biosynthesis. Consequently, the present study provides the basis for establishment of K. baliensis strains as novel microbial cell factories for biotechnologically relevant, unique polysaccharides.
Topics: Acetic Acid; Acetobacteraceae; Bacterial Proteins; Base Sequence; Cellulose; Computer Simulation; DNA Transposable Elements; Fructans; Genome, Bacterial; Gluconacetobacter xylinus; Glycerol; Mannitol; Operon; Polysaccharides, Bacterial; Sequence Analysis, DNA; Sucrose
PubMed: 27716345
DOI: 10.1186/s12934-016-0572-x -
Applied and Environmental Microbiology Jan 2016A wealth of studies has demonstrated that resident microorganisms (microbiota) influence the pattern of nutrient allocation to animal protein and energy stores, but it...
A wealth of studies has demonstrated that resident microorganisms (microbiota) influence the pattern of nutrient allocation to animal protein and energy stores, but it is unclear how the effects of the microbiota interact with other determinants of animal nutrition, including animal genetic factors and diet. Here, we demonstrate that members of the gut microbiota in Drosophila melanogaster mediate the effect of certain animal genetic determinants on an important nutritional trait, triglyceride (lipid) content. Parallel analysis of the taxonomic composition of the associated bacterial community and host nutritional indices (glucose, glycogen, triglyceride, and protein contents) in multiple Drosophila genotypes revealed significant associations between the abundance of certain microbial taxa, especially Acetobacteraceae and Xanthamonadaceae, and host nutritional phenotype. By a genome-wide association study of Drosophila lines colonized with a defined microbiota, multiple host genes were statistically associated with the abundance of one bacterium, Acetobacter tropicalis. Experiments using mutant Drosophila validated the genetic association evidence and reveal that host genetic control of microbiota abundance affects the nutritional status of the flies. These data indicate that the abundance of the resident microbiota is influenced by host genotype, with consequent effects on nutrient allocation patterns, demonstrating that host genetic control of the microbiome contributes to the genotype-phenotype relationship of the animal host.
Topics: Animal Nutritional Physiological Phenomena; Animals; Bacteria; Drosophila melanogaster; Gastrointestinal Microbiome; Gastrointestinal Tract; Phenotype
PubMed: 26567306
DOI: 10.1128/AEM.03301-15 -
MSystems Jun 2024Transovarial transmission is the most reliable way of passing on essential nutrient-providing endosymbionts from mothers to offspring. However, not all endosymbiotic...
Transovarial transmission is the most reliable way of passing on essential nutrient-providing endosymbionts from mothers to offspring. However, not all endosymbiotic microbes follow the complex path through the female host tissues to oocytes on their own. Here, we demonstrate an unusual transmission strategy adopted by one of the endosymbionts of the planthopper (Hemiptera: Tropiduchidae) from Bulgaria. In this species, an endosymbiont is transmitted transovarially within deep invaginations of cellular membranes of an ancient endosymbiont -strikingly resembling recently described plant virus transmission. However, in males, colonizes the same bacteriocytes as but remains unenveloped. Then, the unusual endobacterial localization of observed in females appears to be a unique adaptation to maternal transmission. Further, the symbiont's genomic features, including encoding essential amino acid biosynthetic pathways and its similarity to a recently described psyllid symbiont, suggest a unique combination of the ability to horizontally transmit among species and confer nutritional benefits. The close association with symbiont correlates with the so-far-unreported level of genomic erosion of ancient nutritional symbionts of this planthopper. In , this is reflected in substantial changes in genomic organization, reported for the first time in the symbiont renowned for its genomic stability. In , substantial gene loss resulted in one of the smallest genomes known, at 108.6 kb. Thus, the symbionts of display a combination of unusual adaptations and genomic features that expand our understanding of how insect-microbe symbioses may transmit and evolve.IMPORTANCEReliable transmission across host generations is a major challenge for bacteria that associate with insects, and independently established symbionts have addressed this challenge in different ways. The facultatively endobacterial localization of symbiont, enveloped by cells of ancient nutritional endosymbiont in females but not males of the planthopper , appears to be a unique adaptation to maternal transmission. 's genomic features indicate its unusual evolutionary history, and the genomic erosion experienced by ancient nutritional symbionts demonstrates the apparent consequences of such close association. Combined, this multi-partite symbiosis expands our understanding of the diversity of strategies that insect symbioses form and some of their evolutionary consequences.
PubMed: 38934538
DOI: 10.1128/msystems.00634-24 -
Carbohydrate Polymers Sep 2016The anhydroglucose chains of cellulose possess hydroxyls that facilitate different chemical modification strategies to expand on, or provide new applications for...
The anhydroglucose chains of cellulose possess hydroxyls that facilitate different chemical modification strategies to expand on, or provide new applications for membranes produced by the bacteria Gluconacetobacter xylinus. Conjugation with biomolecules such as proteins, especially by the amine groups, is of great value and interest for the production of biomaterial derivatives from bacterial cellulose. To assist in these modifications, cellulose was succinylated in order to prevent steric hindrance and to create an attachment point for conjugation. Bacterial cellulose membranes were first treated in dichloromethane and reacted with succinic anhydride through a series of conditions. The membrane structure remained intact after these first processes and the product was confirmed by Infra-Red spectroscopy and solid state nuclear magnetic resonance and characterized by X-ray diffraction, thermogravimetry and atomic force microscopy. Hydrolyzed collagen was used as a model protein of interest to be conjugated to these membranes, which furnished a biomaterial functionalized over its surface.
Topics: Biocompatible Materials; Cellulose; Collagen; Gluconacetobacter xylinus; Membranes, Artificial; Thermogravimetry; X-Ray Diffraction
PubMed: 27185111
DOI: 10.1016/j.carbpol.2016.04.033 -
Applied and Environmental Microbiology Sep 2018Animal-associated microorganisms (microbiota) dramatically influence the nutritional and physiological traits of their hosts. To expand our understanding of such...
Animal-associated microorganisms (microbiota) dramatically influence the nutritional and physiological traits of their hosts. To expand our understanding of such influences, we predicted bacterial genes that influence a quantitative animal trait by a comparative genomic approach, and we extended these predictions via mutant analysis. We focused on starvation resistance (SR). We first confirmed that SR responds to the microbiota by demonstrating that bacterium-free flies have greater SR than flies bearing a standard 5-species microbial community, and we extended this analysis by revealing the species-specific influences of 38 genome-sequenced bacterial species on SR. A subsequent metagenome-wide association analysis predicted bacterial genes with potential influence on SR, among which were significant enrichments in bacterial genes for the metabolism of sulfur-containing amino acids and B vitamins. Dietary supplementation experiments established that the addition of methionine, but not B vitamins, to the diets significantly lowered SR in a way that was additive, but not interactive, with the microbiota. A direct role for bacterial methionine metabolism genes in SR was subsequently confirmed by analysis of flies that were reared individually with distinct methionine cycle mutants. The correlated responses of SR to bacterial methionine metabolism mutants and dietary modification are consistent with the established finding that bacteria can influence fly phenotypes through dietary modification, although we do not provide explicit evidence of this conclusion. Taken together, this work reveals that SR is a microbiota-responsive trait, and specific bacterial genes underlie these influences. Extending descriptive studies of animal-associated microorganisms (microbiota) to define causal mechanistic bases for their influence on animal traits is an emerging imperative. In this study, we reveal that starvation resistance (SR), a model quantitative trait in animal genetics, responds to the presence and identity of the microbiota. Using a predictive analysis, we reveal that the amino acid methionine has a key influence on SR and show that bacterial methionine metabolism mutants alter normal patterns of SR in flies bearing the bacteria. Our data further suggest that these effects are additive, and we propose the untested hypothesis that, similar to bacterial effects on fruit fly triacylglyceride deposition, the bacterial influence may be through dietary modification. Together, these findings expand our understanding of the bacterial genetic basis for influence on a nutritionally relevant trait of a model animal host.
Topics: Acetobacter; Animals; Drosophila melanogaster; Escherichia coli; Gastrointestinal Tract; Lactobacillus; Methionine; Microbiota; Starvation; Symbiosis
PubMed: 29934334
DOI: 10.1128/AEM.00662-18 -
Food Chemistry: X Jun 2022Kombucha, originated in China 2000 years ago, is a sour and sweet-tasted drink, prepared traditionally through fermentation of black tea. During the fermentation of...
Kombucha, originated in China 2000 years ago, is a sour and sweet-tasted drink, prepared traditionally through fermentation of black tea. During the fermentation of kombucha, consisting of mainly acidic compounds, microorganisms, and a tiny amount of alcohol, a biofilm called SCOBY forms. The bacteria in kombucha has been generally identified as Acetobacteraceae. Kombucha is a noteworthy source of B complex vitamins, polyphenols, and organic acids (mainly acetic acid). Nowadays, kombucha is tended to be prepared with some other plant species, which, therefore, lead to variations in its composition. Pre-clinical studies conducted on kombucha revealed that it has desired bioactivities such as antimicrobial, antioxidant, hepatoprotective, anti-hypercholestorelomic, anticancer, anti-inflammatory, etc. Only a few clinical studies have been also reported. In the current review, we aimed to overhaul pre-clinical bioactivities reported on kombucha as well as its brief compositional chemistry. The literature data indicate that kombucha has valuable biological effects on human health.
PubMed: 35434600
DOI: 10.1016/j.fochx.2022.100302