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International Journal of Systematic and... Jan 2020Thermotolerant bacterial nanocellulose-producing strains, designated MSKU 9 and MSKU 15, were isolated from persimmon and sapodilla fruits, respectively. These strains...
Thermotolerant bacterial nanocellulose-producing strains, designated MSKU 9 and MSKU 15, were isolated from persimmon and sapodilla fruits, respectively. These strains were aerobic, Gram-stain-negative, had rod-shaped cells, were non-motile and formed white-cream colonies. Phylogeny based on the 16S rRNA gene sequences revealed that MSKU 9 and MSKU 15 represented members of the genus and formed a monophyletic branch with JCM 17123 and DSM 6160. The genomic analysis revealed that overall genomic relatedness index values of MSKU 9 with JCM 17123 and DSM 6160 were ~90 % average nucleotide identity (ANI) and ≤58.2 % digital DNA-DNA hybridization (dDDH), respectively. MSKU 9 and MSKU 15 can be differentiated from the closely related JCM 17123 by their growth on 30 % d-glucose and ability to utilize and to form acid from raffinose and sucrose as carbon sources, and from DSM 6160 by their ability to grow without acetic acid. The genomic DNA G+C contents of MSKU 9 and MSKU 15 were 60.4 and 60.2 mol%, respectively. The major fatty acids of MSKU 9 and MSKU 15 were summed feature 8 (C ω7c and/or Cω6c). The respiratory quinone was determined to be Q10. On the basis of the results of the polyphasic taxonomic analysis, MSKU 9 (=TBRC 9844=NBRC 113802) represents a novel species of the genus , for which the name sp. nov. is proposed.
Topics: Acetobacteraceae; Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Diospyros; Fatty Acids; Fruit; Manilkara; Nucleic Acid Hybridization; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Thailand; Ubiquinone
PubMed: 31622229
DOI: 10.1099/ijsem.0.003745 -
Food Research International (Ottawa,... Dec 2023Kombucha is a natural fermented beverage (mixed system). This study aimed to unravel the signatures of kombucha in China to achieve tailor-made microbial consortium....
Kombucha is a natural fermented beverage (mixed system). This study aimed to unravel the signatures of kombucha in China to achieve tailor-made microbial consortium. Here, biochemical parameters, microbiome, metabolite production and volatile profile were comprehensively compared and characterized across four regions (AH, HN, SD, SX), both commonalities and distinctions were highlighted. The findings revealed that yeast species yeast Starmerella, Zygosaccharomyces, Dekkera, Pichia and bacterium Komagataeibacter, Gluconobacter were the most common microbes. Additionally, the composition, distribution and stability of microbial composition in liquid phase were superior to those in biofilm. The species diversity, differences, marker and association were analyzed across four areas. Metabolite profiles revealed a total of 163 bioactive compounds (23 flavonoids, 13 phenols), and 68 differential metabolites were screened and identified. Moreover, the metabolic pathways of phenylpropanoids biosynthesis were closely linked with the highest number of metabolites, followed by flavonoid biosynthesis. Sixty-five volatile compounds (23 esters) were identified. Finally, the correlation analysis among the microbial composition and volatile and functional metabolites showed that Komagataeibacter, Gluconolactone, Zygosacchaaromycess, Starmerella and Dekkera seemed closely related to bioactive compounds, especially Komagataeibacter displayed positive correlations with 1-hexadecanol, 5-keto-D-gluconate, L-malic acid, 6-aminohexanoate, Starmerella contributed greatly to gluconolactone, thymidine, anabasine, 2-isopropylmalic acid. Additionally, Candida was related to β-damascenone and α-terpineol, and Arachnomyces and Butyricicoccus showed the consistency of associations with specific esters and alcohols. These findings provided crucial information for creating a stable synthetic microbial community structure, shedding light on fostering stable kombucha and related functional beverages.
Topics: Metabolomics; Microbiota; Lactones; China; Saccharomycetales; Acetobacteraceae
PubMed: 37981364
DOI: 10.1016/j.foodres.2023.113652 -
Carbohydrate Polymers Jan 2021Bacterial cellulose (BC) is a good material candidate for wound dressing because of its fine 3-D network structure, high mechanical strength and water holding...
Bacterial cellulose (BC) is a good material candidate for wound dressing because of its fine 3-D network structure, high mechanical strength and water holding capability, and good biocompatibility. In this study, a composite hydrogel was prepared by using 1,4-butanediol diglycidyl ether (BDDE) to cross-link BC and hyaluronic acid (HA). Cross-linked BC/HA composites exhibited a denser and smoother surface. This dense morphology improved water retention capability and dimensional stability. BDDE cross-linked BC/HA composite with 2% HA and 1% BDDE showed better overall properties, including water stability (12.7 % water solubility), mechanical properties (tensile strength: ∼ 0.61 MPa and Young's modulus: ∼1.62 MPa) and thermal stability (maximum degradation temperature: 360 °C), as compared to BC/HA without crosslinking. In addition, cell toxicity assays and morphology indicated the BDDE cross-linked BC/HA composite significantly promoted cell proliferation and adhesion. This chemically cross-linked BC/HA composite may have many new biomedical applications in wound care.
Topics: Acetobacteraceae; Animals; Bandages; Biocompatible Materials; Butylene Glycols; Cell Adhesion; Cell Line; Cell Proliferation; Cellulose; Elastic Modulus; Fibroblasts; Hyaluronic Acid; Hydrogels; Mice; Solubility; Temperature; Tensile Strength
PubMed: 33183589
DOI: 10.1016/j.carbpol.2020.117123 -
Applied Biochemistry and Biotechnology Oct 2023Acetic acid bacteria have a remarkable capacity to cope with elevated concentrations of cytotoxic acetic acid in their fermentation environment. In particular, the...
Acetic acid bacteria have a remarkable capacity to cope with elevated concentrations of cytotoxic acetic acid in their fermentation environment. In particular, the high-level acetate tolerance of Acetobacter pasteurianus that occurs in vinegar industrial settings must be constantly selected for. However, the improved acetic acid tolerance is rapidly lost without a selection pressure. To understand genetic and molecular biology of this acquired acetic acid tolerance in A. pasteurianus, we evolved three strains A. pasteurianus CICIM B7003, CICIM B7003-02, and ATCC 33,445 over 960 generations (4 months) in two initial acetic acids of 20 g·L and 30 g·L, respectively. An acetic acid-adapted strain M20 with significantly improved specific growth rate of 0.159 h and acid productivity of 1.61 g·L·h was obtained. Comparative genome analysis of six evolved strains revealed that the genetic variations of adaptation were mainly focused on lactate metabolism, membrane proteins, transcriptional regulators, transposases, replication, and repair system. Among of these, lactate dehydrogenase, acetolactate synthase, glycosyltransferase, ABC transporter ATP-binding protein, two-component regulatory systems, the type II toxin-antitoxin system (RelE/RelB/StbE), exodeoxyribonuclease III, type I restriction endonuclease, tRNA-uridine 2-sulfurtransferase, and transposase might collaboratively contribute to the improved acetic acid tolerance in A. pasteurianus strains. The balance between repair factors and transposition variations might be the basis for genomic plasticity of A. pasteurianus strains, allowing the survival of populations and their offspring in acetic acid stress fluctuations. These observations provide important insights into the nature of acquired acetic acid tolerance phenotype and lay a foundation for future genetic manipulation of these strains.
Topics: Acetic Acid; Genomics; Fermentation; Acetobacter
PubMed: 36738389
DOI: 10.1007/s12010-023-04353-9 -
Cardiovascular Engineering and... Dec 2020The paper present findings from an in vitro experimental study of a stentless human aortic bioprosthesis (HAB) made of bacterial cellulose (BC). Three variants of the... (Comparative Study)
Comparative Study
PURPOSE
The paper present findings from an in vitro experimental study of a stentless human aortic bioprosthesis (HAB) made of bacterial cellulose (BC). Three variants of the basic model were designed and tested to identify the valve prosthesis with the best performance parameters. The modified models were made of BC, and the basic model of pericardium.
METHODS
Each model (named V, V and V) was implanted into a 90 mm porcine aorta. Effective Orifice Area (EOA), rapid valve opening time (RVOT) and rapid valve closing time (RVCT) were determined. The flow resistance of each bioprosthesis model during the simulated heart systole, i.e. for the mean differential pressure (ΔP) at the time of full valve opening was measured. All experimental specimens were exposed to a mean blood pressure (MBP) of 90.5 ± 2.3 mmHg.
RESULTS
The V model demonstrated the best performance. The index defining the maximum opening of the bioprosthesis during systole for models V, V and V was 2.67 ± 0.59, 2.04 ± 0.23 and 2.85 ± 0.59 cm, respectively. The mean flow rate through the V valve was 5.7 ± 1, 6.9 ± 0.7 and 8.9 ± 1.4 l/min for stroke volume (SV) of 65, 90 and 110 mL, respectively. The phase of immediate opening and closure for models V, V and V was 8, 7 and 5% of the cycle duration, respectively. The mean flow resistance of the models was: 4.07 ± 2.1, 4.28 ± 2.51 and 5.6 ± 2.32 mmHg.
CONCLUSIONS
The V model of the aortic valve prosthesis is the most effective. In vivo tests using BC as a structural material for this model are recommended. The response time of the V model to changed work conditions is comparable to that of a healthy human heart. The model functions as an aortic valve prosthesis in in vitro conditions.
Topics: Animals; Aorta; Bioprosthesis; Cellulose; Gluconacetobacter xylinus; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Hemodynamics; Materials Testing; Prosthesis Design; Sus scrofa
PubMed: 33205361
DOI: 10.1007/s13239-020-00500-z -
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 -
ACS Applied Materials & Interfaces Jan 2022Humidity sensors have been widely used for humidity monitoring in industry and agriculture fields. However, the rigid structure, nondegradability, and large dimension of...
Humidity sensors have been widely used for humidity monitoring in industry and agriculture fields. However, the rigid structure, nondegradability, and large dimension of traditional humidity sensors significantly restrict their applications in wearable fields. In this study, a flexible, strong, and eco-friendly bacterial cellulose-based humidity sensor (BPS) was fabricated using a two-step method, involving solvent evaporation-induced self-assembly and electrolyte permeation. Rapid evaporation of organic solvent induces the formation of nanopores of the bacterial cellulose (BC) surface and promotes structural densification. Furthermore, the successful embedding of potassium hydroxide into the sophisticated network of BC effectively enhanced the sensing performance of BPS. The BPS exhibits an excellent humidity sensing response of more than 10 within the relative humidity ranging from 36.4 to 93% and strong (66.4 MPa) and high flexibility properties owing to the ultrafine fiber network and abundant hydrophilic functional groups of BC. Besides being strong and thin, BPS is also highly flexible, biodegradable, and humidity-sensitive, making it a potential candidate in wearable electronics, human health monitoring, and noncontact switching.
Topics: Biocompatible Materials; Biosensing Techniques; Carbohydrate Conformation; Cellulose; Gluconacetobacter xylinus; Humans; Humidity; Hydrophobic and Hydrophilic Interactions; Materials Testing; Wearable Electronic Devices
PubMed: 34994532
DOI: 10.1021/acsami.1c20163 -
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 -
International Journal of Molecular... Mar 2021This article compares the properties of bacterial cellulose/fish collagen composites (BC/Col) after enzymatic and chemical cross-linking. In our methodology, two... (Comparative Study)
Comparative Study
This article compares the properties of bacterial cellulose/fish collagen composites (BC/Col) after enzymatic and chemical cross-linking. In our methodology, two transglutaminases are used for enzymatic cross-linking-one recommended for the meat and the other proposed for the fish industry-and pre-oxidated BC (oxBC) is used for chemical cross-linking. The structure of the obtained composites is characterized by scanning electron microscopy, thermogravimetric analysis, X-ray diffraction, and Fourier transform infrared spectroscopy, and their functional properties by mechanical and water barrier tests. While polymer chains in uncross-linked BC/Col are intertwined by H-bonds, new covalent bonds in enzymatically cross-linked ones are formed-resulting in increased thermal stability and crystallinity of the material. The C2-C3 bonds cleavage in D-glucose units, due to BC oxidation, cause secondary alcohol groups to vanish in favor of the carbonyl groups' formation, thus reducing the number of H-bonded OHs. Thermal stability and crystallinity of oxBC/Col remain lower than those of BC/Col. The BC/Col formation did not affect tensile strength and water vapor permeability of BC, but enzymatic cross-linking with TG improved them significantly.
Topics: Animals; Cellulose; Collagen; Cross-Linking Reagents; Enzymes; Fishes; Gluconacetobacter; Hydrogen Bonding; Microscopy, Electron, Scanning; Permeability; Polymers; Spectroscopy, Fourier Transform Infrared; Stress, Mechanical; Temperature; Tensile Strength; Thermogravimetry; X-Ray Diffraction
PubMed: 33805875
DOI: 10.3390/ijms22073346 -
International Journal of Biological... Dec 2021A new strain of bacterial cellulose (BC)-producing Gluconobacter cerinus HDX-1 was isolated and identified, and a simple, low-cost complexation method was used to...
A new strain of bacterial cellulose (BC)-producing Gluconobacter cerinus HDX-1 was isolated and identified, and a simple, low-cost complexation method was used to biosynthesis Lactobacillus paracasei 1∙7 bacteriocin BC (BC-B) nanofiber. The structure and antibacterial properties of the nanofibers were evaluated. Solid-state nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR) and x-ray diffraction (XRD) analysis showed that BC and BC-B nanofibers had typical crystalline form of the cellulose I. X-ray photoelectron spectrometer (XPS), scanning electron microscope (SEM) and atomic force microscopy (AFM) revealed that the bacteriocin and BC were successfully compounded, and the structure of BC-B nanofiber was tighter than BC nanofiber, with lower porosity, swelling ratio and water vapor transmission rate (WVTR). The tensile strength and Young's modulus of BC-B nanofibers were 13.28 ± 1.26 MPa and 132.10 ± 4.92 MPa, respectively, higher than that of BC nanofiber (6.12 ± 0.87 MPa and 101.59 ± 5.87 MPa), indicating that bacteriocin enhance the mechanical properties of BC nanofiber. Furthermore, the BC-B nanofibers exhibited significant thermal stability, antioxidant capacity and antibacterial activity than BC nanofiber. Therefore, bacteriocin-loaded BC nanofiber may be used as antimicrobial agents in active food packaging and medical material.
Topics: Anti-Bacterial Agents; Antioxidants; Bacteria; Bacteriocins; Cellulose; DNA, Ribosomal; Elastic Modulus; Gluconobacter; Green Chemistry Technology; Microbial Sensitivity Tests; Nanofibers; Photoelectron Spectroscopy; Spectroscopy, Fourier Transform Infrared; Tensile Strength; X-Ray Diffraction
PubMed: 34737079
DOI: 10.1016/j.ijbiomac.2021.10.176