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Frontiers in Microbiology 2020Bacteria belonging to the genus were frequently isolated from legume nodules. The nodule-inhabiting as a resource of biocontrol and plant growth-promoting endophytes...
Bacteria belonging to the genus were frequently isolated from legume nodules. The nodule-inhabiting as a resource of biocontrol and plant growth-promoting endophytes has rarely been explored. This study explored the nodule-inhabiting ' antifungal activities and biocontrol potentials against broad-spectrum important phytopathogenic fungi. We collected strains which were isolated from nodules of , , , , , or and belong to , , , , , , or closely related to , or . These nodule-inhabiting showed diverse antagonistic activities against five phytopathogenic fungi (, , , , and ). Six strains within the complex showed broad-spectrum and potent activities against all the five pathogens, and produced multiple hydrolytic enzymes, siderophores, and lipopeptide fusaricidins. Fusaricidins are likely the key antimicrobials responsible for the broad-spectrum antifungal activities. The nodule-inhabiting strains within the complex were able to epiphytically and endophytically colonize the non-host wheat plants, produce indole acetic acids (IAA), and dissolve calcium phosphate and calcium phytate. strains RP20, RP51, and RP62 could fix N. RP51 and sp. RP31, which showed potent plant colonization and plant growth-promotion competence, effectively control fungal infection . Genome mining revealed that all strains ( = 76) within the complex contain gene encoding indole-3-pyruvate decarboxylase for biosynthesis of IAA, 96% ( = 73) contain the cluster for biosynthesis of fusaricidins, and 43% ( = 33) contain the cluster for nitrogen fixation. Together, our study highlights that endophytic strains within the complex have a high probability to be effective biocontrol agents and biofertilizers and we propose an effective approach to screen strains within the complex.
PubMed: 33537018
DOI: 10.3389/fmicb.2020.618601 -
Proceedings of the National Academy of... Feb 2021Bacteria are inherently social organisms whose actions should ideally be studied within an interactive ecological context. We show that the exchange and modification of...
Bacteria are inherently social organisms whose actions should ideally be studied within an interactive ecological context. We show that the exchange and modification of natural products enables two unrelated bacteria to defend themselves against a common predator. Amoebal predation is a major cause of death in soil bacteria and thus it exerts a strong selective pressure to evolve defensive strategies. A systematic analysis of binary combinations of coisolated bacteria revealed strains that were individually susceptible to predation but together killed their predator. This cooperative defense relies on a species producing syringafactin, a lipopeptide, which induces the production of peptidases in a strain. These peptidases then degrade the innocuous syringafactin into compounds, which kill the predator. A combination of bioprospecting, coculture experiments, genome modification, and transcriptomics unravel this novel natural product-based defense strategy.
Topics: Amoeba; Animals; Bacteria; Gene Expression Profiling; Lipopeptides; Paenibacillus; Phylogeny; Predatory Behavior; Pseudomonas; Soil Microbiology
PubMed: 33526668
DOI: 10.1073/pnas.2013759118 -
Life Science Alliance Oct 2020is an agriculturally important plant growth-promoting rhizobacterium. Many species are known to be engaged in complex bacteria-bacteria and bacteria-host interactions,...
is an agriculturally important plant growth-promoting rhizobacterium. Many species are known to be engaged in complex bacteria-bacteria and bacteria-host interactions, which in other species were shown to necessitate quorum sensing communication. However, to date, no quorum sensing systems have been described in Here, we show that the type strain ATCC 842 encodes at least 16 peptide-based communication systems. Each of these systems is comprised of a pro-peptide that is secreted to the growth medium and processed to generate a mature short peptide. Each peptide has a cognate intracellular receptor of the RRNPP family, and we show that external addition of communication peptides leads to reprogramming of the transcriptional response. We found that these quorum sensing systems are conserved across hundreds of species belonging to the family, with some species encoding more than 25 different peptide-receptor pairs, representing a record number of quorum sensing systems encoded in a single genome.
Topics: Bacterial Proteins; Genome, Bacterial; Genomics; Paenibacillus; Paenibacillus polymyxa; Plant Development; Quorum Sensing
PubMed: 32764104
DOI: 10.26508/lsa.202000847 -
Scientific Reports Feb 2020Microbial flocculant (MBF), an environmentally friendly water treatment agent, can be widely used in various water treatments. However, its use is limited by low yield...
Microbial flocculant (MBF), an environmentally friendly water treatment agent, can be widely used in various water treatments. However, its use is limited by low yield and high cost. This problem can be solved by clarifying its biosynthesis mechanism and regulating it. Paenibacillus shenyangensis A9, a flocculant-producing bacterium, was used to produce polysaccharide-type MBFA9 by regulating the nitrogen source (nitrogen adequacy/nitrogen deficiency). In this study, RNA-Seq high-throughput sequencing technology and bioinformatic approaches were used to investigate the fermentation and biosynthesis of polysaccharide-type MBFA9 by regulating the nitrogen source (high nitrogen/low nitrogen) in the flocculant-producing bacteria Paenibacillus shenyangensis A9. Differentially expressed genes, functional clustering, and functional annotation of key genes were assessed. Then the MBFA9 biosynthesis and metabolic pathway were reconstructed. Our results showed that when cultured under different nitrogen conditions, bacterial strain A9 had a greater ability to synthesize polysaccharide-type MBFA9 under low nitrogen compared to high nitrogen conditions, with the yield of MBFA9 reaching 4.2 g/L at 36 h of cultivation. The quality of transcriptome sequencing data was reliable, with a matching rate of 85.38% and 85.48% when L36/H36 was mapped to the reference genome. The total expressed genes detected were 4719 and 4730, with 265 differentially expressed genes. The differentially expressed genes were classified into 3 categories: molecular function (MF), cell component (CC), and biological process (BP), and can be further divided into 22 subcategories. There were 192 upregulated genes and 73 downregulated genes, with upregulation being predominant under low nitrogen. UDP-Gal, UDP-Glc, UDP-GlcA, and UDP-GlcNAc, which are in the polysaccharide metabolic pathway, could all be used as precursors for MBFA9 biosynthesis, and murA, wecB, pgm, galU/galF, fcl, gmd, and glgC were the main functional genes capable of affecting the growth of bacteria and the biosynthesis of MBF. Results from this study provide evidence that high-level expression of key genes in MBFA9 biosynthesis, regulation, and control can achieve MBFA9 directional synthesis for large-scale applications.
Topics: Biosynthetic Pathways; Carbon; Flocculation; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Gene Ontology; Genes, Bacterial; Nitrogen; Paenibacillus; Polysaccharides
PubMed: 32075995
DOI: 10.1038/s41598-020-59114-z -
MedRxiv : the Preprint Server For... Sep 2023Neonatal infections due to have increasingly been reported over the last few years. We performed a structured literature review of human infections in infants and...
Neonatal infections due to have increasingly been reported over the last few years. We performed a structured literature review of human infections in infants and adults to compare the epidemiology of infections between these distinct patient populations. Thirty-nine reports describing 176 infections met our inclusion criteria and were included. There were 37 infections occurring in adults caused by 23 species. The clinical presentations of infections were quite variable. In contrast, infections in infants were caused by only 3 species: (112/139, 80%), (2/139, 1%) and (2/139, 1%). All of the infants with infection presented with a sepsis syndrome or meningitis, often complicated by extensive cerebral destruction and hydrocephalus. Outcomes were commonly poor with 17% (24/139) mortality. Cystic encephalomalacia due to brain destruction was common in both Ugandan and American cases and 92/139 (66%) required surgical management of hydrocephalus following their infection. infections are likely underappreciated in infants and effective treatments are urgently needed.
PubMed: 37790370
DOI: 10.1101/2023.09.19.23295794 -
Journal of Insect Science (Online) Mar 2023American foulbrood (AFB) is a cosmopolitan bacterial disease that affects honey bee (Apis mellifera) larvae and causes great economic losses in apiculture. Currently, no... (Review)
Review
American foulbrood (AFB) is a cosmopolitan bacterial disease that affects honey bee (Apis mellifera) larvae and causes great economic losses in apiculture. Currently, no satisfactory methods are available for AFB treatment mainly due to the difficulties to eradicate the tenacious spores produced by the etiological agent of AFB, Paenibacillus larvae (Bacillales, Paenibacillaceae). This present review focused on the beneficial bacteria that displayed antagonistic activities against P. larvae and demonstrated potential in AFB control. Emphases were placed on commensal bacteria (genus Bacillus and lactic acid bacteria in particular) in the alimentary tract of honey bees. The probiotic roles lactic acid bacteria play in combating the pathogenic P. larvae and the limitations referring to the application of these beneficial bacteria were addressed.
Topics: Bees; Animals; United States; Larva; Paenibacillus larvae; Beekeeping; Gastrointestinal Tract
PubMed: 36947033
DOI: 10.1093/jisesa/iead013 -
Journal of Zhejiang University....In this study, plant growth-promoting rhizobacteria (PGPR) were evaluated as potential biocontrol agents against postharvest pathogens of apple fruits. In vitro...
In this study, plant growth-promoting rhizobacteria (PGPR) were evaluated as potential biocontrol agents against postharvest pathogens of apple fruits. In vitro bioassays revealed that, out of 30 isolates screened, isolates APEC136 and APEC170 had the most significant inhibitory effects against the mycelial growth of several fungal pathogens. Analysis of 16S ribosomal RNA (rRNA) sequences identified the two effective isolates as Paenibacillus polymyxa and Bacillus subtilis, respectively. The two strains showed greater growth in brain-heart infusion broth than in other growth media. Treatment of harvested apples with suspensions of either strain reduced the symptoms of anthracnose disease caused by two fungal pathogens, Colletotrichum gloeosporioides and Colletotrichum acutatum, and white rot disease caused by Botryosphaeria dothidea. Increased productions of amylase and protease by APEC136, and increased productions of chitinase, amylase, and protease by APEC170 might have been responsible for inhibiting mycelial growth. The isolates caused a greater reduction in the growth of white rot than of anthracnose. These results indicate that the isolates APEC136 and APEC170 are promising agents for the biocontrol of anthracnose and white rot diseases in apples after harvest, and suggest that these isolates may be useful in controlling these diseases under field conditions.
Topics: Antibiosis; Bacillus subtilis; Fruit; Malus; Paenibacillus polymyxa; Plant Diseases
PubMed: 27921398
DOI: 10.1631/jzus.B1600117 -
Marine Drugs Apr 2021Two new secondary metabolites, svalbamides A () and B (), were isolated from a culture extract of sp. SVB7 that was isolated from surface sediment from a core...
Two new secondary metabolites, svalbamides A () and B (), were isolated from a culture extract of sp. SVB7 that was isolated from surface sediment from a core (HH17-1085) taken in the Svalbard archipelago in the Arctic Ocean. The combinational analysis of HR-MS and NMR spectroscopic data revealed the structures of and as being lipopeptides bearing 3-amino-2-pyrrolidinone, d-valine, and 3-hydroxy-8-methyldecanoic acid. The absolute configurations of the amino acid residues in svalbamides A and B were determined using the advanced Marfey's method, in which the hydrolysates of and were derivatized with l- and d- forms of 1-fluoro-2,4-dinitrophenyl-5-alanine amide (FDAA). The absolute configurations of and were completely assigned by deducing the stereochemistry of 3-hydroxy-8-methyldecanoic acid based on DP4 calculations. Svalbamides A and B induced quinone reductase activity in Hepa1c1c7 murine hepatoma cells, indicating that they represent chemotypes with a potential for functioning as chemopreventive agents.
Topics: Animals; Anticarcinogenic Agents; Arctic Regions; Bacterial Proteins; Carcinoma, Hepatocellular; Cell Line, Tumor; Ecosystem; Geologic Sediments; Humans; Lipopeptides; Liver Neoplasms; Mice; Molecular Structure; NAD(P)H Dehydrogenase (Quinone); Paenibacillus; Structure-Activity Relationship
PubMed: 33920625
DOI: 10.3390/md19040229 -
Marine Drugs Jan 2022As a low molecular weight alginate, alginate oligosaccharides (AOS) exhibit improved water solubility, better bioavailability, and comprehensive health benefits. In...
As a low molecular weight alginate, alginate oligosaccharides (AOS) exhibit improved water solubility, better bioavailability, and comprehensive health benefits. In addition, their biocompatibility, biodegradability, non-toxicity, non-immunogenicity, and gelling capability make them an excellent biomaterial with a dual curative effect when applied in a drug delivery system. In this paper, a novel alginate lyase, Algpt, was cloned and characterized from a marine bacterium, sp. LJ-23. The purified enzyme was composed of 387 amino acid residues, and had a molecular weight of 42.8 kDa. The optimal pH of Algpt was 7.0 and the optimal temperature was 45 °C. The analysis of the conserved domain and the prediction of the three-dimensional structure indicated that Algpt was a novel alginate lyase. The dominant degradation products of Algpt on alginate were AOS dimer to octamer, depending on the incubation time, which demonstrated that Algpt degraded alginate in an endolytic manner. In addition, Algpt was a salt-independent and thermo-tolerant alginate lyase. Its high stability and wide adaptability endow Algpt with great application potential for the efficient preparation of AOS with different sizes and AOS-based products.
Topics: Alginates; Animals; Aquatic Organisms; China; Cloning, Molecular; Drug Delivery Systems; Lyases; Paenibacillus
PubMed: 35049921
DOI: 10.3390/md20010066 -
Genomics Jan 2021The legislations on the usage of antibiotics as growth promoters and prophylactic agents have compelled to develop alternative tools to upsurge the animal protection and...
The legislations on the usage of antibiotics as growth promoters and prophylactic agents have compelled to develop alternative tools to upsurge the animal protection and contain antibiotic usage. Probiotics have emerged as an effective antibiotic substitute in animal farming. The present study explores the probiotic perspective of Paenibacillus polymyxa HK4 interlinking the genotypic and phenotypic characteristics. The draft genome of HK4 revealed the presence of ORFs encoding the functions associated with tolerance to gastrointestinal stress and adhesion. The biosynthetic gene clusters encoding non-ribosomally synthesized peptides, polyketides and lanthipeptides such as fusaricidin, tridecaptin, polymyxin, paenilan and paenibacillin were annotated in HK4 genome. The strain harbored the chromosomal gene conferring the resistance to lincosamides. No functional gene encoding virulence or toxins could be identified in the genome of HK4. The genome analysis data was complemented by the in vitro experiments confirming its survival during gastrointestinal transit, antimicrobial potential and antibiotic sensitivity. NUCLEOTIDE SEQUENCE ACCESSION NUMBER: The draft-genome sequence of Paenibacillus polymyxa HK4 has been deposited as whole-genome shotgun project at GenBank under the accession number PRJNA603023.
Topics: Anti-Bacterial Agents; Genome, Bacterial; Paenibacillus polymyxa; Polyketides; Polymyxins; Probiotics
PubMed: 33096257
DOI: 10.1016/j.ygeno.2020.10.017