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Food Research International (Ottawa,... Oct 2023Light-flavor Baijiu fermentation is a typical spontaneous solid-state fermentation process fueled by a variety of microorganisms. Mechanized processes have been...
Light-flavor Baijiu fermentation is a typical spontaneous solid-state fermentation process fueled by a variety of microorganisms. Mechanized processes have been increasingly employed in Baijiu production to replace traditional manual operation processes, however, the microbiological and physicochemical dynamics in mechanized processes remain largely unknown. Here, we investigated the microbial community succession and flavor compound formation during a whole mechanized fermentation process of light-flavor Baijiu using the conventional dilution plating method, PacBio single-molecule real-time (SMRT) sequencing and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry. The results showed that largely different fungal and bacterial communities were involved in the soaking and fermentation processes. A clear succession from Pantoea agglomerans to Bacillus (B.) smithii and B. coagulans in dominant bacterial species and from Cladosporium exasperatum to Saccharomyces cerevisiae and Lichtheimia ramosa in dominant fungal species occurred in the soaking processes. In the fermentation process, the most dominant bacterial species was shifted from Pantoea agglomerans to Lactobacillus (La.) acetotolerans and the most dominant fungal species were shifted from Lichtheimia ramose and Rhizopus arrhizus to Saccharomyces cerevisiae. The bacterial and fungal species positively associated with acidity and the formation of ethanol and different flavor compounds were specified. The microbial species exhibited strong co-occurrence or co-exclusion relationships were also identified. The results are helpful for the improvement of mechanized fermentation process of light-flavor Baijiu production.
Topics: Saccharomyces cerevisiae; Fermentation; Bacillus; Ethanol; Microbiota; Pantoea
PubMed: 37689903
DOI: 10.1016/j.foodres.2023.113139 -
Applied and Environmental Microbiology Mar 2017Cysteine is a commercially important amino acid; however, it lacks an efficient fermentative production method. Due to its cytotoxicity, intracellular cysteine levels...
Cysteine is a commercially important amino acid; however, it lacks an efficient fermentative production method. Due to its cytotoxicity, intracellular cysteine levels are stringently controlled via several regulatory modes. Managing its toxic effects as well as understanding and deregulating the complexities of regulation are crucial for establishing the fermentative production of cysteine. The regulatory modes include feedback inhibition of key metabolic enzymes, degradation, efflux pumps, and the transcriptional regulation of biosynthetic genes by a master cysteine regulator, CysB. These processes have been extensively studied using for overproducing cysteine by fermentation. In this study, we genetically engineered , an emerging host for the fermentative production of bio-based materials, to identify key factors required for cysteine production. According to this and our previous studies, we identified a major cysteine desulfhydrase gene, (formerly PAJ_0331), involved in cysteine degradation, and the cysteine efflux pump genes and (formerly PAJ_3026 and PAJ_p0018, respectively), which may be responsible for downregulating the intracellular cysteine level. Our findings revealed that deletion and and overexpression are crucial factors for establishing fermentative cysteine production in and for obtaining a higher cysteine yield when combined with genes in the cysteine biosynthetic pathway. To our knowledge, this is the first demonstration of cysteine production in , which has fundamental implications for establishing overproduction in this microbe. The efficient production of cysteine is a major challenge in the amino acid fermentation industry. In this study, we identified cysteine efflux pumps and degradation pathways as essential elements and genetically engineered , an emerging host for the fermentative production of bio-based materials, to establish the fermentative production of cysteine. This study provides crucial insights into the design and construction of cysteine-producing strains, which may play central roles in realizing commercial basis production.
Topics: Amino Acids; Bacterial Proteins; Biotechnology; Cystathionine gamma-Lyase; Cysteine; Down-Regulation; Drug Resistance, Bacterial; Escherichia coli; Fermentation; Gene Expression Regulation, Bacterial; Genetic Engineering; Metabolic Networks and Pathways; Pantoea; Sequence Deletion
PubMed: 28003193
DOI: 10.1128/AEM.02502-16 -
PloS One 2021Cathelicidin (CRAMP) is a defence peptide with a wide range of biological responses including antimicrobial, immunomodulatory and wound healing. Due to its original...
Cathelicidin (CRAMP) is a defence peptide with a wide range of biological responses including antimicrobial, immunomodulatory and wound healing. Due to its original properties the usefulness of CRAMP in the treatment of pulmonary fibrosis was assessed in a murine model of hypersensitivity pneumonitis (HP). The studies were conducted on mouse strain C57BL/6J exposed to a saline extract of Pantoea agglomerans cells (HP inducer). Cathelicidin was administered in the form of an aerosol during and after HP development. Changes in the composition of immune cell populations (NK cells, macrophages, lymphocytes: Tc, Th, Treg, B), were monitored in lung tissue by flow cytometry. Extracellular matrix deposition (collagens, hydroxyproline), the concentration of cytokines involved in inflammatory and the fibrosis process (IFNγ, TNFα, TGFβ1, IL1β, IL4, IL5, IL10, IL12α, IL13) were examined in lung homogenates by the ELISA method. Alterations in lung tissue morphology were examined in mouse lung sections stained with haematoxylin and eosin as well as Masson trichrome dyes. The performed studies revealed that cathelicidin did not cause any negative changes in lung morphology/structure, immune cell composition or cytokines production. At the same time, CRAMP attenuated the immune reaction induced by mice chronic exposure to P. agglomerans and inhibited hydroxyproline and collagen deposition in the lung tissue of mice treated with bacteria extract. The beneficial effect of CRAMP on HP treatment was associated with restoring the balance in quantity of immune cells, cytokines production and synthesis of extracellular matrix components. The presented study suggests the usefulness of cathelicidin in preventing lung fibrosis; however, cathelicidin was not able to reverse pathological changes completely.
Topics: Aerosols; Alveolitis, Extrinsic Allergic; Animals; Cathelicidins; Cytokines; Disease Models, Animal; Female; Lung; Macrophages; Mice; Mice, Inbred C57BL; Pantoea; Pulmonary Fibrosis
PubMed: 33999928
DOI: 10.1371/journal.pone.0251237 -
International Journal of Molecular... May 2023Alfalfa is widely grown worldwide for its excellent nutritional value. species living in alfalfa seeds can easily spread over great distances with frequent trade....
Alfalfa is widely grown worldwide for its excellent nutritional value. species living in alfalfa seeds can easily spread over great distances with frequent trade. However, the pathogenic properties of this dangerous hitchhiker on alfalfa have not been evaluated. Here, we identified the taxonomic status of strain CQ10 isolated from the interior of alfalfa seeds based on the whole genome sequence. The diverse virulence attributes of strain CQ10 during host infection were characterized through pathogenicity assays and functional and genomic analyses. We report that strain CQ10 belongs to a novel species in the genus , which was phylogenetically close to and . Strain CQ10 caused bacterial leaf blight of alfalfa after inoculation from the roots. We found that strain CQ10 possesses a large number of pathogenic genes involved in shaping the virulence properties during bacteria-host interactions, including motility, biofilm, type VI secretion system, and nutrient acquisition. Compared with and , the unique virulence factors of strain CQ10 were mainly involved in motility and biofilm, which were confirmed by in vitro experiments. Taken together, our results suggest that strain CQ10 is the first species to infect alfalfa, and it possesses diverse virulence attributes among which motility and biofilm may be the best weapons.
Topics: Sequence Analysis, DNA; Pantoea; Virulence; Medicago sativa; Genomics
PubMed: 37175847
DOI: 10.3390/ijms24098138 -
Journal of Applied Microbiology May 2006The aims of the study were to identify the effects of rice endophyte Pantoea agglomerans YS19 on host plant growth and allocations of photosynthates.
AIMS
The aims of the study were to identify the effects of rice endophyte Pantoea agglomerans YS19 on host plant growth and allocations of photosynthates.
METHODS AND RESULTS
Endophytic diazotrophic YS19 showed nitrogen-fixing activity in N-free medium, and produced four categories of phytohormones which were indole-3-acetic acid, abscisic acid, gibberellic acid and cytokinin in Luria-Bertani medium. Inoculation of YS19 improved the biomass of the 12-day-cultivated host rice seedlings by 63.4% on N-free medium or by 18.7% on N-supplemented medium. Spraying of YS19 cell culture onto the rice plants at the premilk stage enhanced the transportation of the photosynthetic assimilation product from the source (flag leaves) to the sink (stachys) significantly. The formation of the plant sink was obviously inhibited when YS19 cell culture was applied at the late milk stage.
CONCLUSIONS
This research suggests that endophyte YS19 promotes host rice plant growth and affects allocations of host photosynthates.
SIGNIFICANCE AND IMPACT OF THE STUDY
These findings suggested that YS19 possesses the potential for increasing rice production in field application. Meanwhile, a suitable plant growth stage must be selected for the foliar spraying of YS19 cell culture.
Topics: Biomass; Culture Media; Food Microbiology; Nitrogen Fixation; Oryza; Pantoea; Photosynthesis; Plant Growth Regulators; Seedlings
PubMed: 16629994
DOI: 10.1111/j.1365-2672.2006.02843.x -
Applied and Environmental Microbiology Jul 2011The insect-vectored disease malaria is a major world health problem. New control strategies are needed to supplement the current use of insecticides and medications. A...
The insect-vectored disease malaria is a major world health problem. New control strategies are needed to supplement the current use of insecticides and medications. A genetic approach can be used to inhibit development of malaria parasites (Plasmodium spp.) in the mosquito host. We hypothesized that Pantoea agglomerans, a bacterial symbiont of Anopheles mosquitoes, could be engineered to express and secrete anti-Plasmodium effector proteins, a strategy termed paratransgenesis. To this end, plasmids that include the pelB or hlyA secretion signals from the genes of related species (pectate lyase from Erwinia carotovora and hemolysin A from Escherichia coli, respectively) were created and tested for their efficacy in secreting known anti-Plasmodium effector proteins (SM1, anti-Pbs21, and PLA2) in P. agglomerans and E. coli. P. agglomerans successfully secreted HlyA fusions of anti-Pbs21 and PLA2, and these strains are under evaluation for anti-Plasmodium activity in infected mosquitoes. Varied expression and/or secretion of the effector proteins was observed, suggesting that the individual characteristics of a particular effector may require empirical testing of several secretion signals. Importantly, those strains that secreted efficiently grew as well as wild-type strains under laboratory conditions and, thus, may be expected to be competitive with the native microbiota in the environment of the mosquito midgut.
Topics: Animals; Anopheles; Antimalarials; Bacterial Proteins; Cell Survival; Escherichia coli; Escherichia coli Proteins; Hemolysin Proteins; Microbial Interactions; Pantoea; Pest Control, Biological; Plasmodium; Polysaccharide-Lyases; Protein Sorting Signals; Recombinant Fusion Proteins
PubMed: 21602368
DOI: 10.1128/AEM.00514-11 -
Journal of Food Protection Apr 2004The effectiveness of the strain CPA-2 of Pantoea agglomerans alone or in combination with a curing treatment at 33 degrees C for 65 h to control green mold was evaluated...
The effectiveness of the strain CPA-2 of Pantoea agglomerans alone or in combination with a curing treatment at 33 degrees C for 65 h to control green mold was evaluated on lemons stored at ambient temperature and in cold storage. An application of P. agglomerans at 2 x 10(8) CFU/ml effectively reduced green mold incidence on recently inoculated lemons stored at temperatures from 5 to 25 degrees C. Moreover, a 30-s immersion of lemons in a P. agglomerans suspension at 2 x 10(8) CFU/ml significantly reduced green mold incidence, even when delayed up to 15 h after inoculation with Penicillium digitatum at either 20 degrees C or while in cold storage. However, it failed to control established infections of P. digitatum of more than 24 h. Curing P. agglomerans-treated lemons at 33 degrees C for 65 h completely controlled 24-h-old infections on artificially inoculated lemons stored at 20 degrees C for 14 days and on naturally infected lemons stored at 10 degrees C for 3 weeks plus 7 additional days at 20 degrees C. When applied before curing, population growth of P. agglomerans in wounds was similar to that within wounds of control fruits at 20 degrees C. In contrast, when it was applied immediately after curing treatment, P. agglomerans populations within wounds did not increase.
Topics: Citrus; Colony Count, Microbial; Food Handling; Food Microbiology; Food Preservation; Pantoea; Penicillium; Pest Control, Biological; Temperature; Time Factors
PubMed: 15083731
DOI: 10.4315/0362-028x-67.4.781 -
Frontiers in Microbiology 2022Reduced agricultural production as well as issues like nutrient-depleted soils, eutrophication, and groundwater contamination have drawn attention to the use of...
Reduced agricultural production as well as issues like nutrient-depleted soils, eutrophication, and groundwater contamination have drawn attention to the use of endophyte-based bioformulations to restore soil fertility. CPHN2, a non-rhizobial nodule endophyte isolated from , exhibited a variety of plant growth-promoting traits. In this study, we used NextSeq500 technology to analyze whole-genome sequence information of this plant growth-promoting endophytic bacteria. The genome of CPHN2 has a length of 4,839,532 bp and a G + C content of 55.2%. The whole genome comprises three different genomic fractions, comprising one circular chromosome and two circular plasmids. A comparative analysis between CPHN2 and 10 genetically similar strains was performed using a bacterial pan-genome pipeline. All the predicted and annotated gene sequences for plant growth promotions (PGPs), such as phosphate solubilization, siderophore synthesis, nitrogen metabolism, and indole-3-acetic acid (IAA) of CPHN2, were identified. The whole-genome analysis of CPHN2 provides an insight into the mechanisms underlying PGP by endophytes and its potential applications as a biofertilizer.
PubMed: 36419432
DOI: 10.3389/fmicb.2022.998821 -
Journal of Microbiology, Immunology,... Jun 2013There are only three case reports of adult patients with spontaneous Pantoea agglomerans bacteremia in the English literature. The aim of this study was to investigate...
BACKGROUND/PURPOSE
There are only three case reports of adult patients with spontaneous Pantoea agglomerans bacteremia in the English literature. The aim of this study was to investigate clinical and microbiologic characteristics patients of P agglomerans bacteremia.
METHODS
We studied all adult patients with P agglomerans bacteremia at a medical center from 2000 to 2010. The isolates were identified using two commercial identification systems.
RESULTS
Of the 18 patients identified, 72% (n = 13) had active gastroesophageal disease treated with antacids. Two-thirds of patients had indwelling central lines and advanced cancers. None of the removed catheter tips yielded P agglomerans and line persistence was not associated with adverse outcomes. Initial disease severity was low, hypotension was uncommon and no patient died of bacteremia. Recurrence of bacteremia occurred in one patient with deep-seated infection. 16srRNA gene sequencing identified only half of the isolates as P agglomerans. The remaining nine isolates were Enterobacter species for six, Pantoea ananatis for two, and Exiguobacterium profundum for one. There were no significant differences between the characteristics of the subgroup molecularly identified as P agglomernas and the overall group characteristics. Eleven (61%) of the 18 isolates were susceptible to cefazolin, six (33%) susceptible to fosfomycin (MIC ≤ 64 mg/ml). Two isolates had colistin MICs ≥ 4 mg/ml.
CONCLUSION
Bacteremia caused by P agglomerans is associated with gastroesophageal reflux disease and receipt of antacids. 16srRNA gene sequencing should not be used as the sole basis for its identification and we have highlighted the need for another molecular-based technique to conclusively characterize P agglomerans.
Topics: Academic Medical Centers; Adult; Aged; Antacids; Bacteremia; Enterobacteriaceae Infections; Female; Gastroesophageal Reflux; Humans; Male; Middle Aged; Pantoea; Risk Factors; Taiwan
PubMed: 22841622
DOI: 10.1016/j.jmii.2012.05.005 -
Journal of Applied Microbiology 2002To reduce concentrations of protective and rehydrating media and to evaluate the effect of storage temperature, packaging and atmosphere conditions on the stability of...
AIMS
To reduce concentrations of protective and rehydrating media and to evaluate the effect of storage temperature, packaging and atmosphere conditions on the stability of freeze-dried Pantoea agglomerans cells. Efficacy against Penicillium digitatum of freeze-dried cells in orange fruits was also evaluated.
METHODS AND RESULTS
Several concentrations of protective and rehydration media were tested to reduce processing costs. Freeze-dried cells were packed in glass vials or plastic bags under vacuum or nitrogen conditions at 4 and 25 degrees C. After 1 and 3 months, efficacy of freeze-dried P. agglomerans against P. digitatum was tested.
CONCLUSIONS
The results indicate that it is possible to reduce the concentration of non-fat skimmed milk as a rehydration medium from 10% to 1%, maintaining viabilities of 100%. Moreover, freeze-dried cells could be stored in glass vials or in high barrier plastic bags at 4 degrees C for 3 months while maintaining high viabilities and efficacy against P. digitatum.
SIGNIFICANCE AND IMPACT OF THE STUDY
The major obstacle in the commercialization of biocontrol products is the development of a shelf-stable formulated product that retains biocontrol activity at a level similar to that of fresh cells. This study suggests that it is possible to maintain viability and efficacy of freeze-dried P. agglomerans cells for at least 3 months.
Topics: Atmosphere; Citrus; Food Handling; Food Packaging; Freeze Drying; Pantoea; Penicillium; Pest Control, Biological
PubMed: 11972691
DOI: 10.1046/j.1365-2672.2002.01596.x