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International Journal of Molecular... Apr 2024The potato dry rot disease caused by spp. seriously reduces potato yield and threatens human health. However, potential biocontrol agents cannot guarantee the stability...
The potato dry rot disease caused by spp. seriously reduces potato yield and threatens human health. However, potential biocontrol agents cannot guarantee the stability and activity of biocontrol. Here, 18 synthetic microbial communities of different scales were constructed, and the synthetic microbial communities with the best biocontrol effect on potato dry rot disease were screened through in vitro and in vivo experiments. The results show that the synthetic community composed of , , , , and has the best biocontrol activity. Metabolomics results show that interacts with other member strains to produce caproic acid and reduce the disease index to 38.01%. Furthermore, the mycelial growth inhibition after treatment with caproic acid was 77.54%, and flow cytometry analysis showed that the living conidia rate after treatment with caproic acid was 11.2%. This study provides potential value for the application of synthetic microbial communities in potatoes, as well as the interaction mechanisms between member strains of synthetic microbial communities.
Topics: Solanum tuberosum; Plant Diseases; Biological Control Agents; Fusarium; Microbial Interactions; Bacteria; Microbial Consortia
PubMed: 38674022
DOI: 10.3390/ijms25084437 -
Foods (Basel, Switzerland) Apr 2024Enumeration of endospores of butyric acid-forming clostridia in cheese milk is an essential part of milk quality monitoring for cheese producers to avoid late blowing,...
Enumeration of endospores of butyric acid-forming clostridia in cheese milk is an essential part of milk quality monitoring for cheese producers to avoid late blowing, severe spoilage caused by clostridia during ripening. However, due to the lack of an internationally standardized method, different methods are used and it is important to consider how the choice of method affects the results. This is particularly relevant when clostridial spore counts in milk are considered for quality payments. The aim of this study was to evaluate the specificity of the AMP-6000 method for the enumeration of endospores of cheese spoiling clostridia in milk. First, to assess the prevalence of diversity and to determine potential non-target species, we identified isolates from positive reactions of the AMP-6000 method used to quantify clostridial endospores in raw milk and teat skin samples by MALDI-TOF MS. Based on these results, a strain library was designed to evaluate method inclusivity and exclusivity using pure cultures of target and non-target strains according to ISO 16140-2:2016. Most target strains, as well as all tested and strains were inclusive. However, may be underestimated as only some strains gave positive results. All non-target strains of bacilli and lysinibacilli, but not all paenibacilli, were confirmed to be exclusive. This study provides performance data to better understand the results of microbiological enumeration of butyric acid-forming clostridia in milk and serves as a basis for future methodological considerations and improvements.
PubMed: 38672865
DOI: 10.3390/foods13081192 -
Insects Apr 2024American foulbrood is an infectious disease of the honeybee brood that causes multiple types of damage to beekeeping. The causative agent of the disease is the bacterium...
American foulbrood is an infectious disease of the honeybee brood that causes multiple types of damage to beekeeping. The causative agent of the disease is the bacterium , which forms resistant infective spores and is viable for decades. After the eradication measures have been implemented, in cases of clinically visible disease, it is necessary to conduct effective final disinfections of equipment and tools. This study aimed to determine the effect of ten commercially available and commonly used disinfectants on certified strains of under laboratory conditions, as well as to compare the obtained results among individual genotypes of . Selected products were tested by determining the zone of inhibition using an agar diffusion test, a suspension test for viable bacteria, a surface disinfectant test, and a sporicidal effect in the suspension test. Incidin OxyFoam S and Sekusept Aktiv are both effective against all examined genotypes of . Despadac and Despadac Secure have a bactericidal effect, but their sporocidal effect is not as satisfactory as that of Genox. Genoll does not exhibit a sporicidal effect, and Ecocide S at 1%, Bee protect H forte, and Bee protect F did not exhibit a satisfactory sporocidal effect. Additionally, EM PROBIOTIC FOR BEES did not exhibit any bactericidal effect. The effective application of control measures and proper application of final disinfection can reduce the reoccurrence of visible clinical signs of disease, whereas methods of early diagnosis can significantly reduce the incidence of the disease.
PubMed: 38667398
DOI: 10.3390/insects15040268 -
Beneficial Microbes Sep 2023Honey bee colonies form a complex superorganism, with individual and social immune defences that control overall colony health. Sometimes these defences are not enough...
Honey bee colonies form a complex superorganism, with individual and social immune defences that control overall colony health. Sometimes these defences are not enough to overcome infections by parasites and pathogens. For that reason, several studies have been conducted to evaluate different strategies to improve honey bee health. A novel alternative that is being studied is the use of beneficial microbes. In a previous study, we isolated and characterised bacterial strains from the native gut microbiota of honey bees. Four Apilactobacillus kunkeei strains were mixed and administered in laboratory models to evaluate their potential beneficial effect on larvae and adult bees. This beneficial microbe mixture was safe; it did not affect the expression of immune-related genes, and it was able to decrease the mortality caused by Paenibacillus larvae infection in larvae and reduced the Nosema ceranae spore number in infected adult honey bees. In the present study, we aimed to delve into the impact of the administration of this beneficial microbe mixture on honey bee colonies, under field conditions. The mixture was administered in sugar syrup using lyophilised bacterial cells or fresh cultures, by aspersion or sprayed and feeder, once a week for three consecutive weeks, in autumn or spring 2015, 2017 and 2019. Colony strength parameters were estimated before the administration, and one and three months later. Simultaneously different samples were collected to evaluate the infection levels of parasites and pathogens. The results showed that administering the beneficial microbe mixture decreased or stabilised the infection by N. ceranae or Varroa destructor in some trials but not in others. However, it failed to improve the colony's strength parameters or honey production. Therefore, field studies can be a game-changer when beneficial microbes for honey bees are tested, and meticulous studies should be performed to test their effectiveness.
Topics: Bees; Animals; Nosema; Larva; Gastrointestinal Microbiome; Probiotics; Honey; Paenibacillus larvae
PubMed: 38661390
DOI: 10.1163/18762891-20220099 -
Journal of Hazardous Materials Jun 2024Microplastics (MPs) pose a threat to farmland soil quality and crop safety. MPs exist widely in food legumes farmland soil due to the extensive use of agricultural film...
Microplastics (MPs) pose a threat to farmland soil quality and crop safety. MPs exist widely in food legumes farmland soil due to the extensive use of agricultural film and organic fertilizer, but their distribution characteristics and their impact on soil environment have not been reported. The abundance and characteristics of MPs, soil physical and chemical properties, and bacterial community composition were investigated in 76 soil samples from five provinces in northern China. The results showed that the abundance of MPs ranged from 1600 to 36,200 items/kg. MPs in soil were mostly fibrous, less than 0.2 mm, and white. Rayon, polyester and polyethylene were the main types of MPs. The influences of MPs on soil physicochemical properties and bacterial communities mainly depended on the type of MPs. Notably, polyethylene significantly decreased the proportion of silt particles, and increased the nitrate nitrogen content as well as the abundance of MPs-degrading bacteria Paenibacillus (p < 0.05). Moreover, bacteria were more sensitive to polyesters in soil with low concentration of organic matter. This study indicated that MPs in food legumes farmland soil presented a higher-level. And, they partially altered soil physicochemical properties, and soil bacteria especially in soil with low organic matter.
Topics: China; Soil Microbiology; Soil Pollutants; Soil; Microplastics; Bacteria; Fabaceae; Agriculture; Farms
PubMed: 38657509
DOI: 10.1016/j.jhazmat.2024.134282 -
Revista Argentina de Microbiologia Apr 2024Phytopathogenic fungi Alternaria alternata and Colletotrichum gloeosporioides cause diseases in plant tissues as well as significant postharvest losses. The use of...
Phytopathogenic fungi Alternaria alternata and Colletotrichum gloeosporioides cause diseases in plant tissues as well as significant postharvest losses. The use of chemical fungicides for their control has negative effects on health and the environment. Secondary metabolites from halophilic bacteria are a promising alternative for new antifungal compounds. In the present study, halophilic bacteria were isolated and characterized from two sites with saline soils called branquizales in Campeche, Mexico. A total of 64 bacteria were isolated. Agrobacterium, Bacillus, Inquilinus, Gracilibacillus, Metabacillus, Neobacillus, Paenibacillus, Priestia, Staphylococcus, Streptomyces and Virgibacillus were among the identified genera. The antifungal potential of the culture supernatant (CS) of 39 halophilic bacteria was investigated against C. gloeosporioides and A. alternata. The bacteria showing the greatest inhibition of mycelial growth corresponded to Bacillus subtilis CPO 4292, Metabacillus sp. CPO 4266, Bacillus sp. CPO 4295 and Bacillus sp. CPO 4279. The CS of Bacillus sp. CPO 4279 exhibited the highest activity and its ethyl acetate extract (AcOEt) inhibited the germination of C. gloeosporioides, with IC values of 8,630μg/ml and IC of 10,720μg/ml. The organic partition of the AcOEt extract led to three fractions, with acetonitrile (FAcB9) showing the highest antifungal activity, with values exceeding 66%. Halophilic bacteria from 'blanquizales' soils of the genus Bacillus sp. produce metabolites with antifungal properties that inhibit the phytopathogenic fungus C. gloeosporioides.
PubMed: 38614909
DOI: 10.1016/j.ram.2024.02.004 -
International Journal of Systematic and... Apr 2024Two Gram-positive, rod-shaped, endospore-forming strains, YIM B05601 and YIM B05602, were isolated from soil sampled at Hamazui hot spring, Tengchong City, Yunnan...
Two Gram-positive, rod-shaped, endospore-forming strains, YIM B05601 and YIM B05602, were isolated from soil sampled at Hamazui hot spring, Tengchong City, Yunnan Province, PR China. Phylogenetic analysis based on 16S rRNA gene sequences suggested that the two strains fell within the genus , appearing most closely related to YIM B00362 (96.9 % sequence similarity). Genome-based phylogenetic analysis confirmed that strains YIM B05601 and YIM B05602 formed a distinct phylogenetic cluster within the genus . The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values of strains YIM B05601 and YIM B05602 with the related species YIM B00362 were within the ranges of 74.43-74.57 % and 12.1-18.5 %, respectively, which clearly indicated that strains YIM B05601, YIM B05602 represented a novel species. Strains YIM B05601 and YIM B05602 exhibited 99.6 % 16S rRNA gene sequence similarity. The ANI and dDDH values between the two strains were 99.8 and 100 %, respectively, suggesting that they belong to the same species. Optimum growth for both strains occurred at pH 7.0 and 45 °C. The diagnostic diamino acid in the cell-wall peptidoglycan of strains YIM B05601 and YIM B05602 was -diaminopimelic acid. MK-7 was the predominant menaquinone. The polar lipids of strain YIM B05602 were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, four unidentified glycolipids, an unidentified polarlipid and phosphatidylinositol mannoside. The major fatty acids of the two stains were iso-C and anteiso-C. Based on phylogenomic and phylogenetic analyses coupled with phenotypic and chemotaxonomic characterizations, strains YIM B05601 and YIM B05602 could be classified as a novel species of the genus , for which the name sp. nov. is proposed. The type strain is YIM B05602 (=CGMCC 1.60051=KCTC 43460=NBRC 115924).
Topics: China; Fatty Acids; Hot Springs; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; DNA, Bacterial; Bacterial Typing Techniques; Base Composition; Nucleotides; Paenibacillus
PubMed: 38607368
DOI: 10.1099/ijsem.0.006336 -
Frontiers in Bioengineering and... 2024The demand for highly robust and metabolically versatile microbes is of utmost importance for replacing fossil-based processes with biotechnological ones. Such an...
The demand for highly robust and metabolically versatile microbes is of utmost importance for replacing fossil-based processes with biotechnological ones. Such an example is the implementation of DSM 365 as a novel platform organism for the production of value-added products such as 2,3-butanediol or exopolysaccharides. For this, a complete genome sequence is the first requirement towards further developing this host towards a microbial chassis. A genome sequencing project has just been reported for DSM 365 showing a size of 5,788,318 bp with a total of 47 contigs. Herein, we report the first complete genome sequence of DSM 365, which consists of 5,889,536 bp with 45 RNAs, 106 tRNAs, 5,370 coding sequences and an average GC content of 45.6%, resulting in a closed genome of 365. The additional nucleotide data revealed a novel NRPS synthetase that may contribute to the production of tridecaptin. Building on these findings, we initiated the top-down construction of a chassis variant of . In the first stage, single knock-out mutants of non-essential genomic regions were created and evaluated for their biological fitness. As a result, two out of 18 variants showed impaired growth. The remaining deletion mutants were combined in two genome-reduced variants which either lack the production of endogenous biosynthetic gene clusters (GR1) or non-essential genomic regions including the insertion sequence IS (GR2), with a decrease of the native genome of 3.0% and 0.6%, respectively. Both variants, GR1 and GR2, showed identical growth characteristics to the wild-type. Endpoint titers of 2,3-butanediol and EPS production were also unaffected, validating these genome-reduced strains as suitable for further genetic engineering.
PubMed: 38605990
DOI: 10.3389/fbioe.2024.1378873 -
The Science of the Total Environment Jun 2024Fiber film have received widespread attention due to its green friendliness. We can use microorganisms to degrade lignin in straw to obtain cellulose and make fiber...
Fiber film have received widespread attention due to its green friendliness. We can use microorganisms to degrade lignin in straw to obtain cellulose and make fiber films. Herein, a group of high-temperature (50 °C) lignin degrading bacterial consortium (LDH) was enriched and culture conditions for lignin degradation were optimized. Combined with high-throughput sequencing technology, the synergistic effect of LDH-composited bacteria was analyzed. Then LDH was used to treat rice straw for the bio-pulping experiment. The results showed that the lignin of rice straw was degraded 32.4 % by LDH at 50 °C for 10 d, and after the optimization of culture conditions, lignin degradation rate increased by 9.05 % (P < 0.001). The bacteria that compose in LDH can synergistically degrade lignin. Paenibacillus can encode all lignin-degrading enzymes present in the LDH. Preliminary tests of LDH in the pulping industry have been completed. This study is the first to use high temperature lignin degrading bacteria to fabricate fiber film.
Topics: Lignin; Oryza; Biodegradation, Environmental; Microbial Consortia; Bacteria; Cellulose
PubMed: 38604360
DOI: 10.1016/j.scitotenv.2024.172386 -
ACS Chemical Biology May 2024The prevalence of multidrug-resistant (MDR) pathogens combined with a decline in antibiotic discovery presents a major challenge for health care. To refill the discovery...
The prevalence of multidrug-resistant (MDR) pathogens combined with a decline in antibiotic discovery presents a major challenge for health care. To refill the discovery pipeline, we need to find new ways to uncover new chemical entities. Here, we report the global genome mining-guided discovery of new lipopeptide antibiotics tridecaptin A and tridecaptin D, which exhibit unusual bioactivities within their class. The change in the antibacterial spectrum of Oct-TriA was explained solely by a Phe to Trp substitution as compared to Oct-TriA, while Oct-TriD contained 6 substitutions. Metabolomic analysis of producer sp. JJ-21 validated the predicted amino acid sequence of tridecaptin A. Screening of tridecaptin analogues substituted at position 9 identified Oct-His9 as a potent congener with exceptional efficacy against and reduced hemolytic and cytotoxic properties. Our work highlights the promise of tridecaptin analogues to combat MDR pathogens.
Topics: Anti-Bacterial Agents; Pseudomonas aeruginosa; Humans; Microbial Sensitivity Tests; Host Specificity; Drug Discovery; Lipopeptides; Peptides
PubMed: 38602492
DOI: 10.1021/acschembio.4c00034