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Scientific Reports Aug 2017Bacterial cellulose (BC) is widely used in industries owing to its high purity and strength. Although Komagataeibacter nataicola is a representative species for BC...
Bacterial cellulose (BC) is widely used in industries owing to its high purity and strength. Although Komagataeibacter nataicola is a representative species for BC production, its intracellular metabolism leading to BC secretion is unclear. In the present study, a genome-scale metabolic network of cellulose-producing K. nataicola strain RZS01 was reconstructed to understand its metabolic behavior. This model iHZ771 comprised 771 genes, 2035 metabolites, and 2014 reactions. Constraint-based analysis was used to characterize and evaluate the critical intracellular pathways. The analysis revealed that a total of 71 and 30 genes are necessary for cellular growth in a minimal medium and complex medium, respectively. Glycerol was identified as the optimal carbon source for the highest BC production. The minimization of metabolic adjustment algorithm identified 8 genes as potential targets for over-production of BC. Overall, model iHZ771 proved to be a useful platform for understanding the physiology and BC production of K. nataicola.
Topics: Acetobacteraceae; Cellulose; Culture Media; Genome, Bacterial; Glycerol; Metabolic Networks and Pathways; Models, Biological
PubMed: 28801647
DOI: 10.1038/s41598-017-06918-1 -
Insects Aug 2022Queen bees and worker bees both develop from fertilized eggs, whereas queens live longer than workers. The mechanism of this phenomenon is worth exploring. Antioxidant...
The Comparison of Antioxidant Performance, Immune Performance, IIS Activity and Gut Microbiota Composition between Queen and Worker Bees Revealed the Mechanism of Different Lifespan of Female Casts in the Honeybee.
Queen bees and worker bees both develop from fertilized eggs, whereas queens live longer than workers. The mechanism of this phenomenon is worth exploring. Antioxidant capacity, immune and IIS are the conserved mechanisms of aging. The importance of gut bacteria for health prompted us to connect with bee aging. Therefore, the differences of antioxidant, immune, IIS and gut microflora between queen and worker bees were compared to find potential mechanisms of queens' longevity. The results showed queens had stronger antioxidant capacity and lower immune pathway and IIS activity than workers. The higher expression level of and in queens resulted in the stronger ROS scavenging ability, which leads to the lower ROS level and the reduced accumulation of oxidative damage products in queens. The lower expression and higher antimicrobial peptides (AMPs) expressions in queens suggested that queens maintain lower immune pathway activity and stronger immune capacity than workers. Gut bacteria composition analysis indicated that queens had supernal Acetobacteraceae (notably , and over workers. In conclusion, antioxidant, immune, IIS, and gut symbiotic bacteria all contribute to the longevity of queens. This study provides more insights into revealing the mechanisms of queens' longevity.
PubMed: 36135473
DOI: 10.3390/insects13090772 -
ACS Applied Materials & Interfaces Nov 2021Actuated structures are becoming relevant in medical fields; however, they call for flexible/soft-base materials that comply with biological tissues and can be...
Actuated structures are becoming relevant in medical fields; however, they call for flexible/soft-base materials that comply with biological tissues and can be synthesized in simple fabrication steps. In this work, we extend the palette of techniques to afford soft, actuable spherical structures taking advantage of the biosynthesis process of bacterial cellulose. Bacterial cellulose spheres (BCS) with localized magnetic nanoparticles (NPs) have been biosynthesized using two different one-pot processes: in agitation and on hydrophobic surface-supported static culture, achieving core-shell or hollow spheres, respectively. Magnetic actuability is conferred by superparamagnetic iron oxide NPs (SPIONs), and their location within the structure was finely tuned with high precision. The size, structure, flexibility and magnetic response of the spheres have been characterized. In addition, the versatility of the methodology allows us to produce actuated spherical structures adding other NPs (Au and Pt) in specific locations, creating Janus structures. The combination of Pt NPs and SPIONs provides moving composite structures driven both by a magnetic field and a HO oxidation reaction. Janus Pt/SPIONs increased by five times the directionality and movement of these structures in comparison to the controls.
Topics: Acetobacteraceae; Cellulose; Hydrogen Peroxide; Hydrophobic and Hydrophilic Interactions; Magnetic Fields; Magnetite Nanoparticles; Oxidation-Reduction; Particle Size; Surface Properties
PubMed: 34766498
DOI: 10.1021/acsami.1c17752 -
Microbial Biotechnology Sep 2023The excessive consumption of alcohol results in a dysbiosis of the gut microbiota, which subsequently impairs the gut microbiota-brain/liver axes and induces cognitive...
The excessive consumption of alcohol results in a dysbiosis of the gut microbiota, which subsequently impairs the gut microbiota-brain/liver axes and induces cognitive dysfunction and hepatic injury. This study aimed to investigate the potential effect of Acetobacter pasteurianus BP2201 in reducing the negative effects of alcohol consumption on cognitive function and liver health by modulating the gut microbiota-brain/liver axes. Treatment with A. pasteurianus BP2201 improved alcohol-induced hippocampal damage, suppressed neuroinflammation, promoted neuroprotein expression in the hippocampus and enhanced cognitive function. At the same time, A. pasteurianus BP2201 can also reduce serum lipid levels, relieve oxidative stress, inhibit TLR4/MyD88/NF-κB pathway, reduce the secretion of TNF-α and IL-1β, so as to improve alcoholic liver injury. Concomitantly, the treatment with A. pasteurianus BP2201 leads to a shift in the intestinal microbiota structure towards that of healthy individuals, inhibiting the proliferation of harmful bacteria and promoting the recovery of beneficial bacteria. In addition, it also improves brain cognitive dysfunction and liver health by affecting the gut microbiota-brain/liver axes by promoting the synthesis of relevant amino acids and the metabolism of nucleotide base components. These findings demonstrate the potential of regulating the gut microbiome and gut microbiota-brain/liver axes to mitigate alcohol-induced disease.
Topics: Mice; Animals; Gastrointestinal Microbiome; Liver; Ethanol; Acetobacter; Mice, Inbred C57BL; Dysbiosis
PubMed: 37354051
DOI: 10.1111/1751-7915.14303 -
Applied Microbiology and Biotechnology Aug 2020The strains of the Komagataeibacter genus have been shown to be the most efficient bacterial nanocellulose producers. Although exploited for many decades, the studies of... (Review)
Review
The strains of the Komagataeibacter genus have been shown to be the most efficient bacterial nanocellulose producers. Although exploited for many decades, the studies of these species focused mainly on the optimisation of cellulose synthesis process through modification of culturing conditions in the industrially relevant settings. Molecular physiology of Komagataeibacter was poorly understood and only a few studies explored genetic engineering as a strategy for strain improvement. Only since recently the systemic information of the Komagataeibacter species has been accumulating in the form of omics datasets representing sequenced genomes, transcriptomes, proteomes and metabolomes. Genetic analyses of the mutants generated in the untargeted strain modification studies have drawn attention to other important proteins, beyond those of the core catalytic machinery of the cellulose synthase complex. Recently, modern molecular and synthetic biology tools have been developed which showed the potential for improving targeted strain engineering. Taking the advantage of the gathered knowledge should allow for better understanding of the genotype-phenotype relationship which is necessary for robust modelling of metabolism as well as selection and testing of new molecular engineering targets. In this review, we discuss the current progress in the area of Komagataeibacter systems biology and its impact on the research aimed at scaled-up cellulose synthesis as well as BNC functionalisation. Key points • The accumulated omics datasets advanced the systemic understanding of Komagataeibacter physiology at the molecular level. • Untargeted and targeted strain modification approaches have been applied to improve nanocellulose yield and properties. • The development of modern molecular and synthetic biology tools presents a potential for enhancing targeted strain engineering. • The accumulating omic information should improve modelling of Komagataeibacter's metabolism as well as selection and testing of new molecular engineering targets.
Topics: Acetobacteraceae; Carbohydrate Metabolism; Cellulose; Genetic Engineering; Genotype; Phenotype; Systems Biology
PubMed: 32529377
DOI: 10.1007/s00253-020-10671-3 -
Microbial Ecology Oct 2023Bacteria residing in the guts of pollinating insects play a key role in nutrient acquisition, digestion, and resistance to pests and diseases. Imbalances in microbial...
Bacteria residing in the guts of pollinating insects play a key role in nutrient acquisition, digestion, and resistance to pests and diseases. Imbalances in microbial flora in response to environmental change and stress can therefore impact insect health and resilience. This study is aimed at defining the core gut microbiome of the Australian native stingless bee, Tetragonula carbonaria, and exploring the impact of colony transplantation on gut health. The gut microbiomes of nine forager bees from natural (log) and manufactured (box) hives were examined via 16S rRNA gene amplicon sequencing. Some differences were observed at the ASV level between the microbiomes of log and box hive bees. However, a core microbiome, dominated by Lactobacillus spp., unclassified Acetobacteraceae spp., and Bombella spp., was maintained. Further, the inferred functional potential of the microbiomes was consistent across all individuals. This study highlights that although hive transplantation has an impact on the overall diversity of stingless bee gut microbiomes, it is unlikely to have a significant negative impact on the overall health and resilience of the colony.
Topics: Bees; Animals; Gastrointestinal Microbiome; Australia; RNA, Ribosomal, 16S; Microbiota; Urticaria
PubMed: 37088849
DOI: 10.1007/s00248-023-02222-w -
PeerJ 2022Acetic acid bacteria are well-known for their ability to incompletely oxidize their carbon sources. Many of the products of these oxidations find industrial uses....
Acetic acid bacteria are well-known for their ability to incompletely oxidize their carbon sources. Many of the products of these oxidations find industrial uses. Metabolic engineering of acetic acid bacteria would improve production efficiency and yield by allowing controllable gene expression. However, the molecular tools necessary for regulating gene expression have only recently started being explored. To this end the ability of the activation-dependent P system and two constitutive repression P systems were examined for their ability to modulate gene expression in . The activation-dependent P system increased gene expression approximately 5-fold regardless of the strength of the constitutive promoter used to express the transcriptional activator. The P system was tunable and had a nearly 20-fold induction when the gene was expressed from the strong constitutive promoters P and P, but only had a 4-fold induction when a weak constitutive promoter (P) was used for expression. However, the P system was somewhat leaky when uninduced. To mitigate this background activity, a bicistronic TetR expression system was constructed. Based on molecular modeling, this system is predicted to have low background activity when not induced with anhydrotetracycline. The bicistronic system was inducible up to >3,000-fold and was highly tunable with almost no background expression when uninduced, making this bicistronic system potentially useful for engineering and possibly other acetic acid bacteria. These expression systems add to the newly growing repertoire of suitable regulatable promoter systems in acetic acid bacteria.
Topics: Gluconobacter oxydans; Promoter Regions, Genetic; Oxidation-Reduction
PubMed: 35873911
DOI: 10.7717/peerj.13639 -
Nature Communications Oct 2018Vector-borne diseases are a substantial portion of the global disease burden; one of the deadliest of these is malaria. Vector control strategies have been hindered by...
Vector-borne diseases are a substantial portion of the global disease burden; one of the deadliest of these is malaria. Vector control strategies have been hindered by mosquito and pathogen resistances, and population alteration approaches using transgenic mosquitos still have many hurdles to overcome before they can be implemented in the field. Here we report a paratransgenic control strategy in which the microbiota of Anopheles stephensi was engineered to produce an antiplasmodial effector causing the mosquito to become refractory to Plasmodium berghei. The midgut symbiont Asaia was used to conditionally express the antiplasmodial protein scorpine only when a blood meal was present. These blood meal inducible Asaia strains significantly inhibit pathogen infection, and display improved fitness compared to strains that constitutively express the antiplasmodial effector. This strategy may allow the antiplasmodial bacterial strains to survive and be transmitted through mosquito populations, creating an easily implemented and enduring vector control strategy.
Topics: Acetobacteraceae; Animals; Animals, Genetically Modified; Anopheles; Antibiosis; Digestive System; Disease Resistance; Malaria; Microbiota; Mosquito Vectors; Plasmodium berghei; Symbiosis
PubMed: 30297781
DOI: 10.1038/s41467-018-06580-9 -
Genome Biology and Evolution Oct 2020Recent declines in the health of the honey bee have startled researchers and lay people alike as honey bees are agriculture's most important pollinator. Honey bees are... (Comparative Study)
Comparative Study
Recent declines in the health of the honey bee have startled researchers and lay people alike as honey bees are agriculture's most important pollinator. Honey bees are important pollinators of many major crops and add billions of dollars annually to the US economy through their services. One factor that may influence colony health is the microbial community. Indeed, the honey bee worker digestive tract harbors a characteristic community of bee-specific microbes, and the composition of this community is known to impact honey bee health. However, the honey bee is a superorganism, a colony of eusocial insects with overlapping generations where nestmates cooperate, building a hive, gathering and storing food, and raising brood. In contrast to what is known regarding the honey bee worker gut microbiome, less is known of the microbes associated with developing brood, with food stores, and with the rest of the built hive environment. More recently, the microbe Bombella apis was identified as associated with nectar, with developing larvae, and with honey bee queens. This bacterium is related to flower-associated microbes such as Saccharibacter floricola and other species in the genus Saccharibacter, and initial phylogenetic analyses placed it as sister to these environmental bacteria. Here, we used comparative genomics of multiple honey bee-associated strains and the nectar-associated Saccharibacter to identify genomic changes that may be associated with the ecological transition to honey bee association. We identified several genomic differences in the honey bee-associated strains, including a complete CRISPR/Cas system. Many of the changes we note here are predicted to confer upon Bombella the ability to survive in royal jelly and defend themselves against mobile elements, including phages. Our results are a first step toward identifying potential function of this microbe in the honey bee superorganism.
Topics: Acetic Acid; Acetobacteraceae; Animals; Bees; Gene Transfer, Horizontal; Genome, Bacterial; Phylogeny; Symbiosis
PubMed: 32870981
DOI: 10.1093/gbe/evaa183 -
Biology Dec 2022The influence of climate change on microbial communities inhabiting the sparsely vegetated patterned ground soils that are widespread across the High Arctic is poorly...
The influence of climate change on microbial communities inhabiting the sparsely vegetated patterned ground soils that are widespread across the High Arctic is poorly understood. Here, in a four-year experiment on Svalbard, we warmed patterned ground soil with open top chambers and biannually irrigated the soil to predict the responses of its microbial community to rising temperatures and precipitation. A 1 °C rise in summertime soil temperature caused 44% and 78% increases in CO efflux and CH consumption, respectively, and a 32% increase in the frequency of bacterial 16S ribosomal RNA genes. Bacterial alpha diversity was unaffected by the treatments, but, of the 40 most frequent bacterial taxa, warming caused 44-45% reductions in the relative abundances of a sp. and sp. and 33-91% increases in those of a sp. and a member of the . Warming did not influence the frequency of fungal internal transcribed spacer 2 copies, and irrigation had no effects on the measured variables. Our study suggests rapid changes to the activities and abundances of microbes, and particularly bacteria, in High Arctic patterned ground soils as they warm. At current rates of soil warming on Svalbard (0.8 °C per decade), we anticipate that similar effects to those reported here will manifest themselves in the natural environment by approximately the mid 2030s.
PubMed: 36552329
DOI: 10.3390/biology11121819