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Bioengineered Apr 2022Agricultural residues are constantly increasing with increased farming processes, and improper disposal is detrimental to the environment. Majority of these waste...
Agricultural residues are constantly increasing with increased farming processes, and improper disposal is detrimental to the environment. Majority of these waste residues are rich in lignocellulose, which makes them suitable substrate for bacterial fermentation in the production of value-added products. In this study, bacterial cellulose (BC), a purer and better form of cellulose, was produced by two sp. isolated from rotten banana and kombucha drink using corncob (CC) and sugarcane bagasse (SCB) enzymatic hydrolyzate, under different fermentation conditions, that is, static, continuous, and intermittent agitation. The physicochemical and mechanical properties of the BC films were then investigated by Fourier Transformed Infrared Spectroscopy (FTIR), Thermogravimetry analysis, Field Emission Scanning Electron Microscopy (FE-SEM), and Dynamic mechanical analysis. Agitation gave a higher BC yield, with sp. CCUG73629 producing BC from CC with a dry weight of 1.6 g/L and 1.4 g/L under continuous and intermittent agitation, respectively, compared with that of 0.9 g/L in HS medium. While BC yield of dry weight up to 1.2 g/L was obtained from SCB by sp. CCUG73630 under continuous agitation compared to that of 0.3 g/L in HS medium. FTIR analysis showed BC bands associated with cellulose I, with high thermal stability. The FE-SEM analysis showed that BC fibers were highly ordered and densely packed. Although the BC produced by both strains showed similar physicochemical and morphological properties, the BC produced by the sp. CCUG73630 in CC under intermittent agitation had the best modulus of elasticity, 10.8 GPa and tensile strength, 70.9 MPa.
Topics: Acetobacteraceae; Agriculture; Cellulose; Culture Media; Fermentation; Saccharum
PubMed: 35416127
DOI: 10.1080/21655979.2022.2062970 -
Journal of Agricultural and Food... Apr 2018This study was to probe the effects of bacterial cellulose (BC) on diphenoxylate-induced constipation in rats. Administration with BC at 500 mg/kg of body weight in...
This study was to probe the effects of bacterial cellulose (BC) on diphenoxylate-induced constipation in rats. Administration with BC at 500 mg/kg of body weight in diphenoxylate-induced constipation rats distinctly improved the carmine propulsion rate (83.5 ± 5.2%), shortened the defecating time of the first red feces (249.0 ± 23.3 min), and increased the weight of carmine red feces within 5 h (2.7 ± 1.3 g). The levels of aquaporins (AQP-2, AQP-3, and AQP-4) and inhibitory neurotransmitters (nitric oxide, nitric oxide synthetase, vasoactive intestinal peptide, and arginine vasopressin) in the BC-treated groups reduced by 31.9-40.0% ( p < 0.01) and 21.1-67.7% ( p < 0.01) compared to those in the constipation group, respectively. However, the secretion of excitability neurotransmitters (substance P and motilin) in the BC-treated groups was increased by 20.0-39.9% ( p < 0.01). The activities of ATPases in the colon of constipation rats were significantly weakened by BC administration ( p < 0.01). Histological morphology of the colon showed that BC supplementation could effectively increase the length of villus cells and the thickness of colonic mucosa and muscle ( p < 0.01). Moreover, BC supplementation could protect colonic smooth muscle cells against apoptosis. All of the findings suggest that BC supplementation effectively relieves constipation in rats and BC would be used as a great promising dietary fiber for alleviating constipation.
Topics: Acetobacteraceae; Animals; Aquaporins; Cellulose; Constipation; Defecation; Diphenoxylate; Humans; Intestinal Mucosa; Male; Motilin; Rats; Rats, Sprague-Dawley; Substance P
PubMed: 29627986
DOI: 10.1021/acs.jafc.8b00385 -
Applied Microbiology and Biotechnology Jun 2021Acetic acid bacteria (AAB) are a group of Gram-negative and strictly aerobic microorganisms widely used in vinegar industry, especially the species belonging to the... (Review)
Review
Acetic acid bacteria (AAB) are a group of Gram-negative and strictly aerobic microorganisms widely used in vinegar industry, especially the species belonging to the genera Acetobacter and Komagataeibacter. The environments inhabited by AAB during the vinegar fermentation, in particular those natural traditional bioprocesses, are complex and dynamically changed, usually accompanied by diverse microorganisms, bacteriophages, and the increasing acetic acid concentration. For this reason, how AAB survive to such harsh niches has always been an interesting research field. Previous omic analyses (e.g., genomics, proteomics, and transcriptomics) have provided abundant clues for the metabolic pathways and bioprocesses indispensable for the acid stress adaptation of AAB. Nevertheless, it is far from fully understanding what factors regulate these modular mechanisms overtly and covertly upon shifting environments. Bacterial toxin-antitoxin systems (TAS), usually consisting of a pair of genes encoding a stable toxin and an unstable antitoxin that is capable of counteracting the toxin, have been uncovered to have a variety of biological functions. Recent studies focusing on the role of TAS in Acetobacter pasteurianus suggest that TAS contribute substantially to the acid stress resistance. In this mini review, we discuss the biological functions of type II TAS in the context of AAB with regard to the acid stress resistance, persister formation and resuscitation, genome stability, and phage immunity. KEY POINTS: • Type II TAS act as regulators in the acid stress resistance of AAB. • Type II TAS are implicated in the formation of acid-tolerant persister cells in AAB. • Type II TAS are potential factors responsible for phage immunity and genome stability.
Topics: Acetic Acid; Acetobacter; Cell Physiological Phenomena; Fermentation; Toxin-Antitoxin Systems
PubMed: 34021811
DOI: 10.1007/s00253-021-11357-0 -
Antonie Van Leeuwenhoek Aug 2022In this study, a novel bacterium designated F3b2 was isolated from the gut sample of weaver ant Oecophylla smaragdina and characterised. Strain F3b2 was a Gram-negative,...
In this study, a novel bacterium designated F3b2 was isolated from the gut sample of weaver ant Oecophylla smaragdina and characterised. Strain F3b2 was a Gram-negative, aerobic, non-motile, ovoid-shaped bacterium and grows optimally at 28-30 °C. Its major respiratory quinone is ubiquinone 10 (Q-10) and the major fatty acids are C ω7c, C cyclo ω8c and C, representing 85% of the total fatty acids. The 16S rRNA gene sequence of strain F3b2 was highest in similarity to that of Oecophyllibacter saccharovorans DSM106907 and Swingsia samuieinsis NBRC 107927 at 94.35% and 91.96%, respectively. A 16S rRNA gene-based phylogenetic analysis and a core genes-based phylogenomic analysis placed strain F3b2 in a distinct lineage in the family Acetobacteraceae. The phylogenetic placement was supported by lower than species delineation threshold average nucleotide identity (ANI) (≤ 70.2%), in silico DNA-DNA hybridization (DDH) (≤ 39.5%) and average amino acid identity (AAI) (≤ 63.5%) values between strain F3b2 and closest neighbours. These overall genome relatedness indices also supported the assignment of strain F3b2 to a novel genus within Acetobacteraceae. The genome of strain F3b2 was 1.96 Mb with 60.4% G + C DNA content. Based on these results, strain F3b2 represented a novel taxon of Acetobacteraceae, for which we proposed the name Formicincola oecophyllae gen. nov. sp. nov., and strain F3b2 (= LMG 30590 = DSM 106908 = NBRC 113640 = KCTC 62951) as the type strain.
Topics: Acetobacteraceae; Animals; Ants; Bacterial Typing Techniques; DNA, Bacterial; Fatty Acids; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Ubiquinone
PubMed: 35674967
DOI: 10.1007/s10482-022-01750-8 -
International Journal of Systematic and... Oct 2019A heterotrophic and acidophilic bacterial strain, G45-3, was isolated from acidic mine drainage sampled in Fujian Province, PR China. Cells of strain G45-3 were...
A heterotrophic and acidophilic bacterial strain, G45-3, was isolated from acidic mine drainage sampled in Fujian Province, PR China. Cells of strain G45-3 were Gram-stain-negative, non-spore-forming, non-motile and rod-shaped. Catalase and oxidase activities were positive. Strain G45-3 grew aerobically at 20-45 °C (optimum, 37 °C) and at pH 2.5-5.0 (optimum, pH 4.0). Photosynthetic pigments were not produced. Analysis of 16S rRNA gene sequences showed that strain G45-3 was phylogenetically related to different members of the family , and the sequence identities to JCM 10600, G2-11 and ATCC 35887 were 95.9 , 95.3 and 95.3 %, respectively. Strain G45-3 contained ubiquinone-10 as its respiratory quinone. The major polar lipids were determined to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified aminophospholipid and an unidentified aminolipid. The predominant fatty acids were cyclo-Cω8, Cω7, C and C. The genome of G45-3 consists of one chromosome (3 907 406 bp) and three plasmids (68 344, 45 771 and 16 090 bp), with an average G+C content of 65.9 mol%. Based on the results of phenotypic and genomic analyses, it is concluded that strain G45-3 represents a novel species of a new genus, for which the name gen. nov., sp. nov. is proposed. is nominated as type species and its type strain is G45-3 (=CGMCC 1.16069=KCTC 62275).
Topics: Acetobacteraceae; Acids; Bacterial Typing Techniques; Base Composition; China; DNA, Bacterial; Fatty Acids; Mining; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Ubiquinone
PubMed: 31355740
DOI: 10.1099/ijsem.0.003618 -
BMC Structural Biology Nov 2014Bacterial pyruvate decarboxylases (PDC) are rare. Their role in ethanol production and in bacterially mediated ethanologenic processes has, however, ensured a continued...
BACKGROUND
Bacterial pyruvate decarboxylases (PDC) are rare. Their role in ethanol production and in bacterially mediated ethanologenic processes has, however, ensured a continued and growing interest. PDCs from Zymomonas mobilis (ZmPDC), Zymobacter palmae (ZpPDC) and Sarcina ventriculi (SvPDC) have been characterized and ZmPDC has been produced successfully in a range of heterologous hosts. PDCs from the Acetobacteraceae and their role in metabolism have not been characterized to the same extent. Examples include Gluconobacter oxydans (GoPDC), G. diazotrophicus (GdPDC) and Acetobacter pasteutrianus (ApPDC). All of these organisms are of commercial importance.
RESULTS
This study reports the kinetic characterization and the crystal structure of a PDC from Gluconacetobacter diazotrophicus (GdPDC). Enzyme kinetic analysis indicates a high affinity for pyruvate (K M 0.06 mM at pH 5), high catalytic efficiencies (1.3 • 10(6) M(-1) • s(-1) at pH 5), pHopt of 5.5 and Topt at 45°C. The enzyme is not thermostable (T½ of 18 minutes at 60°C) and the calculated number of bonds between monomers and dimers do not give clear indications for the relatively lower thermostability compared to other PDCs. The structure is highly similar to those described for Z. mobilis (ZmPDC) and A. pasteurianus PDC (ApPDC) with a rmsd value of 0.57 Å for Cα when comparing GdPDC to that of ApPDC. Indole-3-pyruvate does not serve as a substrate for the enzyme. Structural differences occur in two loci, involving the regions Thr341 to Thr352 and Asn499 to Asp503.
CONCLUSIONS
This is the first study of the PDC from G. diazotrophicus (PAL5) and lays the groundwork for future research into its role in this endosymbiont. The crystal structure of GdPDC indicates the enzyme to be evolutionarily closely related to homologues from Z. mobilis and A. pasteurianus and suggests strong selective pressure to keep the enzyme characteristics in a narrow range. The pH optimum together with reduced thermostability likely reflect the host organisms niche and conditions under which these properties have been naturally selected for. The lack of activity on indole-3-pyruvate excludes this decarboxylase as the enzyme responsible for indole acetic acid production in G. diazotrophicus.
Topics: Amino Acids; Bacterial Proteins; Crystallography, X-Ray; Gluconacetobacter; Models, Molecular; Phylogeny; Protein Conformation; Protein Structure, Quaternary; Protein Structure, Tertiary; Pyruvate Decarboxylase; Sarcina; Sequence Homology, Amino Acid; Substrate Specificity; Zymomonas
PubMed: 25369873
DOI: 10.1186/s12900-014-0021-1 -
Journal of Food Science May 2024It is crucial to clarify the stability of Kombucha in the manufacture and storage stages due to the extensive study on the fermented products of Kombucha and the...
It is crucial to clarify the stability of Kombucha in the manufacture and storage stages due to the extensive study on the fermented products of Kombucha and the increase in the use of bacterial cellulose (BC). This study aimed to evaluate the stability of Kombucha in different manufacturing and storage temperatures within a certain time period. The stability of microorganisms and BC in Kombucha was investigated through regular replacement with the tea media at 28 and 25°C for manufacture, and the storage temperature of Kombucha was at 25, 4, and -20°C. Morphological observations of the BC in Kombucha ended at 28 and 25°C for manufacture and storage were performed using atomic force microscopy (AFM) before inoculation. The viable cell counts and AFM results showed that the stability of Kombucha during manufacture was better at 28°C than at 25°C, with higher microbial viability and BC productivity in the former at the time of manufacture, whereas 25°C was more favorable for the stability of Kombucha during storage. At the same temperature of 25°C, the manufacturing practice improved the microbial viability and BC stability compared with storage; the pH value of Kombucha was lower, and the dry weight of BC was higher during storage compared with manufacture. The maximum BC water holding capacity (97.16%) was maintained by storage at 4°C on day 63, and the maximum BC swelling rate (56.92%) was observed after storage at -20°C on day 7. The research was conducted to provide reference information for applying Kombucha and its BC in food and development in other industries.
Topics: Cellulose; Temperature; Fermentation; Food Storage; Food Microbiology; Kombucha Tea; Hydrogen-Ion Concentration; Microbial Viability; Acetobacteraceae; Food Handling
PubMed: 38591324
DOI: 10.1111/1750-3841.16975 -
International Journal of Systematic and... Sep 2021Honey bees are important pollinators of many major crops and add billions of dollars annually to the US economy through their services. Recent declines in the health of...
Honey bees are important pollinators of many major crops and add billions of dollars annually to the US economy through their services. 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. One factor that may influence colony health is the microbial community. Although honey bee worker guts have a characteristic community of bee-specific microbes, the honey bee queen digestive tracts are colonized predominantly by a single acetic acid bacterium tentatively named ''. This bacterium is related to flower-associated microbes such as , and initial phylogenetic analyses placed it as sister to these environmental bacteria. We used a combination of phylogenetic and sequence identity methods to better resolve evolutionary relationships among '', strains in the genus , and strains in the closely related genus . Interestingly, measures of genome-wide average nucleotide identity and aligned fraction, coupled with phylogenetic placement, indicate that many strains labelled as '' and species are all the same species as . We propose reclassifying these strains as and outline the data supporting that classification below.
Topics: Acetobacteraceae; Animals; Bacterial Typing Techniques; Base Composition; Bees; DNA, Bacterial; Fatty Acids; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 34546865
DOI: 10.1099/ijsem.0.004950 -
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