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Frontiers in Plant Science 2022The root-knot nematode, , is a major pest in tomato production. , which is primarily found in soil and colonizing roots, is considered a successful biocontrol organism...
The root-knot nematode, , is a major pest in tomato production. , which is primarily found in soil and colonizing roots, is considered a successful biocontrol organism against many pathogens. To evaluate the biocontrol capacity of LMG27872 against in tomato, experiments were conducted both and . A dose-response effect [30, 50, and 100% (10 CFU/mL)] of bacterial suspensions (BSs) on growth and tomato susceptibility to with soil drenching as a mode of application was first evaluated. The results show that the biological efficacy of LMG27872 against parasitism in tomato was dose-dependent. A significantly reduced number of galls, egg-laying females (ELF), and second-stage juveniles (J2) were observed in BS-treated plants, in a dose-dependent manner. The effect of on tomato growth was also dose-dependent. A high dose of BSs had a negative effect on growth; however, this negative effect was not observed when the BS-treated plants were challenged with , indicating tolerance or a defense priming mechanism. In subsequent experiments, the direct effect of BSs was evaluated on J2 mortality and egg hatching of . The effect of BS on J2 mortality was observed from 12 to 24 h, whereby J2 was significantly inhibited by the BS treatment. The effect of on egg hatching was also dependent on the BS dose. The results show a potential of LMG27872 to protect plants from nematode parasitism and its implementation in integrated nematode management suitable for organic productions.
PubMed: 36186028
DOI: 10.3389/fpls.2022.961085 -
The Journal of General and Applied... Sep 2022Paenibacillus polymyxa is a spore-forming Gram-positive bacterial species. Both its sporulation process and the spore properties are poorly understood. Here, we...
Paenibacillus polymyxa is a spore-forming Gram-positive bacterial species. Both its sporulation process and the spore properties are poorly understood. Here, we investigated sporulation in P. polymyxa ATCC39564. When cultured at 37℃ for 24 h in sporulation medium, more than 80% of the total cells in the culture were spores. Time-lapse imaging revealed that cellular morphological changes during sporulation of P. polymyxa were highly similar to those of B. subtilis. We demonstrated that genetic deletion of spo0A, sigE, sigF, sigG, or sigK, which are highly conserved transcriptional regulators in spore forming bacteria, abolished spore formation. In P. polymyxa, spo0A was required for cell growth in sporulation medium, as well as for the initiation of sporulation. The sigE and sigF mutants formed abnormal multiple asymmetric septa during the early stage of sporulation. The sigG and sigK mutants formed forespores in the sporangium, but they did not become mature. Moreover, fluorescence reporter analysis confirmed compartment-specific gene expression of spoIID and spoVFA in the mother cell and spoIIQ and sspF in the forespore. Transmission electron microscopy imaging revealed that P. polymyxa produces multilayered endospores but lacking a balloon-shaped exosporium. Our results indicate that spore morphogenesis is conserved between P. polymyxa and B. subtilis. However, P. polymyxa genomes lack many homologues encoding spore-coat proteins that are found in B. subtills, suggesting that there are differences in the spore coat composition and surface structure between P. polymyxa and B. subtilis.
Topics: Bacillus subtilis; Bacterial Proteins; Gene Expression Regulation, Bacterial; Morphogenesis; Paenibacillus polymyxa; Spores, Bacterial; Transcription Factors
PubMed: 35418538
DOI: 10.2323/jgam.2021.10.006 -
3 Biotech May 2018Genome sequence of ND25 isolated from cow rumen is reported for being a potential candidate in hydrolysis of lignocellulosic plant biomass. Draft genome sequence...
Genome sequence of ND25 isolated from cow rumen is reported for being a potential candidate in hydrolysis of lignocellulosic plant biomass. Draft genome sequence generated 5.73 Mb data containing 4922 putative protein coding genes, of which 140 are annotated for glycoside hydrolases. ND25 strain comprises diverse lignocellulolytic components, especially 12 cellulase along with 23 hemicellulases and 11 esterases, signifying its potential for lignocellulose hydrolysis. Subsequent enzyme assay exhibited the potential of strain to produce 0.49, 0.24 and 0.44 U/ml U/ml of endoglucanase, exoglucanase and β-glucosidase, respectively, utilizing sugarcane bagasse as the sole carbon source. This study signifies the efficient application of ND25 for facilitating plant-biomass utilization.
PubMed: 29744280
DOI: 10.1007/s13205-018-1274-3 -
Pest Management Science Nov 2023Kiwifruit bacterial canker (KBC) caused by Pseudomonas syringae pv. actinidiae (Psa) is the main limiting factor in the kiwifruit industry. This study aimed to identify...
BACKGROUND
Kiwifruit bacterial canker (KBC) caused by Pseudomonas syringae pv. actinidiae (Psa) is the main limiting factor in the kiwifruit industry. This study aimed to identify bacterial strains with antagonistic activity against Psa, analyze antagonistically active substances and provide a new basis for the biological control of KBC.
RESULTS
A total of 142 microorganisms were isolated from the rhizosphere soil of asymptomatic kiwifruit. Among them, an antagonistic bacterial strain was identified as Paenibacillus polymyxa YLC1 by 16S rRNA sequencing. KBC control by strain YLC1 (85.4%) was comparable to copper hydroxide treatment (81.8%) under laboratory conditions and field testing. Active substances of strain YLC1 were identified by genetic sequence analysis using antiSMASH. Six biosynthetic active compound gene clusters were identified as encoding ester peptide synthesis, such as polymyxins. An active fraction was purified and identified as polymyxin B1 using chromatography, hydrogen nuclear magnetic resonance (NMR), and liquid chromatography-mass spectrometry. In addition, polymyxin B1 also was found significantly to suppress the expression of T3SS-related genes, but did not affect the growth of Psa at low concentrations.
CONCLUSION
In this study, a biocontrol strain P. polymyxa YLC1 obtained from kiwifruit rhizosphere soil exhibited excellent control effects on KBC in vitro and in field tests. Its active compound was identified as polymyxin B1, which inhibits a variety of pathogenic bacteria. We conclude that P. polymyxa YLC1 is a biocontrol strain with excellent prospects for development and application. © 2023 Society of Chemical Industry.
PubMed: 37417001
DOI: 10.1002/ps.7633 -
Microbiology Resource Announcements Jan 2022Paenibacillus polymyxa SRT9.1 is an epiphytic bacterium capable of inhibiting plant-pathogenic bacteria. The strain has potential for development as a biocontrol agent...
Paenibacillus polymyxa SRT9.1 is an epiphytic bacterium capable of inhibiting plant-pathogenic bacteria. The strain has potential for development as a biocontrol agent for use in agriculture. We report the whole-genome sequence of Paenibacillus polymyxa SRT9.1, consisting of 6,754,470 bp and 7,878 coding sequences, with an average G+C content of 45%.
PubMed: 35049350
DOI: 10.1128/mra.01097-21 -
Antonie Van Leeuwenhoek Jan 2021Cacao represents an important source of income for farmers in the south of Mexico. However, phytosanitary problems have disrupted the production over the years. The use...
Cacao represents an important source of income for farmers in the south of Mexico. However, phytosanitary problems have disrupted the production over the years. The use of antagonistic microorganisms as biocontrol agents might improve the production of cacao. In this study, Paenibacillus polymyxa NMA1017, isolated from the rhizosphere of Opuntia ficus-indica L., was used as a biocontrol agent for black pod rot of Theobroma cacao L. cultivated in Chiapas, Mexico. The experiments were carried in vitro and in vivo using pear fruit (Pyrous communis) as model and cacao pods in the field, respectively. The effect of NMA1017 on the phytopathogen was observed by electron microscopy and the production of enzymes was tested as a potential mechanism of action. The bacterium inhibited the radial growth of Phytophthora tropicalis PtCa-14 by 85.9 ± 0.12%. The strain NMA1017 affected mycelial development, as observed by the damage to the cell wall of the oomycete. In pear fruit, the biocontrol agent controlled the production of mycelium on the pear fruit surface, indicating an inhibitory effect exerted. Cacao pods infected with P. tropicalis in the field resulted in a reduction in disease incidence from 86 to 33% and in infection from 68 to 6%. Moreover, strain NMA1017 produced hydrolytic enzymes such as cellulases, xylanases, chitinases and proteases. The results obtained highlight P. polymyxa NMA1017 as an organism of interest for the biocontrol of P. tropicalis, as a method to rescue this important crop in Mexico.
Topics: Cacao; Mexico; Paenibacillus polymyxa; Phytophthora; Plant Diseases
PubMed: 33230721
DOI: 10.1007/s10482-020-01498-z -
Methods in Molecular Biology (Clifton,... 2024In recent years, the clustered regularly interspaced palindromic repeats-Cas (CRISPR-Cas) technology has become the method of choice for precision genome editing in many...
In recent years, the clustered regularly interspaced palindromic repeats-Cas (CRISPR-Cas) technology has become the method of choice for precision genome editing in many organisms due to its simplicity and efficacy. Multiplex genome editing, point mutations, and large genomic modifications are attractive features of the CRISPR-Cas9 system. These applications facilitate both the ease and velocity of genetic manipulations and the discovery of novel functions. In this protocol chapter, we describe the use of a CRISPR-Cas9 system for multiplex integration and deletion modifications, and deletions of large genomic regions by the use of a single guide RNA (sgRNA), and, finally, targeted point mutation modifications in Paenibacillus polymyxa.
Topics: Gene Editing; CRISPR-Cas Systems; RNA, Guide, CRISPR-Cas Systems; Paenibacillus polymyxa; Genome
PubMed: 38468094
DOI: 10.1007/978-1-0716-3658-9_16 -
3 Biotech Mar 2021Konjac glucomannan oligosaccharide has attracted much attention due to its broad biological activities. Specific glucomannan degrading enzymes are effective tools for...
Konjac glucomannan oligosaccharide has attracted much attention due to its broad biological activities. Specific glucomannan degrading enzymes are effective tools for the production of oligosaccharides from konjac glucomannan. However, there are still few reports of commercial enzymes that can specifically degrade konjac glucomannan. The gene encoding a glucomannanase consisting of 553 amino acids (61.5 kDa) from 3-3 was cloned and heterologous expressed in BL21 (DE3). The recombinant GluB showed high specificity for the degradation of konjac glucomannan. Moreover, the hydrolytic products of GluB degrade konjac glucomannan were a series of oligosaccharides with degrees of polymerisation of 2-12. Furthermore, the biochemical properties indicated that GluB is the optimal active at 45 to 55 °C and pH 5.0-6.0, and shows highly pH stability over a very broad pH range. The present characteristics indicated that GluB is a potential tool to be used to produce oligosaccharides from konjac glucomannan.
PubMed: 33680694
DOI: 10.1007/s13205-021-02676-0 -
Plants (Basel, Switzerland) Jun 2023is a plant growth-promoting rhizobacteria (PGPR) that has significant biocontrol properties. Wheat sheath blight caused by is a significant soil-borne disease of wheat...
is a plant growth-promoting rhizobacteria (PGPR) that has significant biocontrol properties. Wheat sheath blight caused by is a significant soil-borne disease of wheat that causes significant losses in wheat production, and the biological control against the disease has received extensive attention. ZYPP18 was identified using morphological and molecular characterization. An antagonistic activity experiment verified that ZYPP18 inhibits the growth of on artificial growth media. A detached leaf assay verified that ZYPP18 inhibits the expansion of wheat sheath blight on the detached leaf. ZYPP18 has been found to possess plant growth-promoting properties, as well as the ability to solubilize phosphate and generate indole-3-acetic acid. Results from hydroponic experiments showed that wheat seedlings treated with ZYPP18 grew faster. Additionally, pot experiments and field experiments demonstrated that ZYPP18 effectively controls the occurrence of wheat sheath blight. ZYPP18 reduced the incidence of wheat sheath blight in wheat seedlings by 37.37% and 37.90%, respectively. The control effect of ZYPP18 on wheat sheath blight was 56.30% and 65.57%, respectively. These findings provide evidence that ZYPP18 is an effective biological factor that can control disease and promote plant growth.
PubMed: 37447065
DOI: 10.3390/plants12132504 -
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