Establishment and application of quantitative detection of Bacillus velezensis HMB26553, a biocontrol agent against cotton damping-off caused by Rhizoctonia.

A highly sensitive quantitative PCR (qPCR) method was developed for detection and quantification of Bacillus velezensis HMB26553 in cotton rhizosphere. The study aimed to develop a quantitative detection method for the strain HMB26553, and explore the relationship between its colonization of the cotton rhizosphere and its control effect. The whole genome sequence of strain HMB26553 was obtained by genome sequencing and a unique specific sequence pB-gene0026 on plasmid plaBV2 was identified by using high-throughput alignment against NCBI.

Complete genome sequence of B31, a potential biocontrol agent with ability of tolerance to fusaric acid and antagonism against .

B31 is tolerant to fusaric acid, exhibits antagonism against , and has an excellent control effect on tomato fusarium wilt. Here, we present the complete genome sequence of B31, which contains 4,056,755 bp DNA with a G + C ratio of 46.39%.

Arabinose Plays an Important Role in Regulating the Growth and Sporulation of NCD-2.

A microbial fungicide developed from NCD-2 has been registered for suppressing verticillium wilt in crops in China. Spores are the main ingredient of this fungicide and play a crucial role in suppressing plant disease. Therefore, increasing the number of spores of strain NCD-2 during fermentation is important for reducing the cost of the fungicide.

Screening Biocontrol Agents for Cash Crop Fusarium Wilt Based on Fusaric Acid Tolerance and Antagonistic Activity against .

Fusarium wilt, caused by , is one of the most notorious diseases of cash crops. The use of microbial fungicides is an effective measure for controlling Fusarium wilt, and the genus is an important resource for the development of microbial fungicides. Fusaric acid (FA) produced by can inhibit the growth of , thus affecting the control efficacy of microbial fungicides.

Functional Analyses of the HMB26553 Genome Provide Evidence That Its Genes Are Potentially Related to the Promotion of Plant Growth and Prevention of Cotton Rhizoctonia Damping-Off.

spp. is one kind of the important representative biocontrol agents against plant diseases and promoting plant growth. In this study, the whole genomic sequence of bacterial strain HMB26553 was obtained.

Colonization Ability of NCD-2 in Different Crops and Its Effect on Rhizosphere Microorganisms.

strain NCD-2 is a promising biocontrol agent for soil-borne plant diseases and shows potential for promoting the growth of some crops. The purposes of this study were to analyze the colonization ability of strain NCD-2 in different crops and reveal the plant growth promotion mechanism of strain NCD-2 by rhizosphere microbiome analysis. qRT-PCR was used to determine the populations of strain NCD-2, and microbial communities' structures were analyzed through amplicon sequencing after application of strain NCD-2.

Insights into complex infection by two Pectobacterium species causing potato blackleg and soft rot.

Pectobacterium spp. are causative agents of blackleg and soft rot of potato. However, little is known about the relationship between the pathogenicity of mixed infections of different Pectobacterium spp.

iTRAQ-based proteomic analysis of Bacillus subtilis strain NCD-2 regulated by PhoPR two-component system: A comparative analysis with transcriptomics revealed the regulation for fengycin production by branched chain amino acids.

The PhoPR two-component system (TCS) is a signal transduction pathway to regulate the phosphate starvation response in Bacillus subtilis and regulated fengycin production in strain NCD-2 under low phosphate condition. The purpose of this study was to characterize the proteome level responses in the phoP-null mutant (MP) and the phoR-null mutant (MR), and to integrate the proteomics with the transcriptomic data obtained previously. The metabolic pathway for fengycin was predicted based on omics analysis as well as molecular genetics assay.

First Report of Verticillium Wilt of Watermelon Caused by Verticillium dahliae in China.

Watermelon (Citrullus lanatus T.) is one of the most important economic crops in China. Soil-borne diseases are becoming more and more serious with longer growing seasons and continuous cropping of watermelon in greenhouses.

Using a phenotype microarray and transcriptome analysis to elucidate multi-drug resistance regulated by the PhoR/PhoP two-component system in Bacillus subtilis strain NCD-2.

The PhoRP two-component system (TCS), one of the most important signaling pathways in Bacillus subtilis, regulates cell physiological reactions mainly under phosphate starvation conditions. The mechanism by which PhoRP TCS regulates resistance towards antibiotics in B. subtilis strain NCD-2 was investigated in this study.

Qualitative and Quantitative Analyses of the Colonization Characteristics of Bacillus subtilis Strain NCD-2 on Cotton Root.

Bacillus subtilis strain NCD-2 is an excellent biocontrol agent against plant soil-borne diseases. With the purpose of understanding the colonization characteristics of strain NCD-2, firstly, a constitutive expression promoter was cloned from strain NCD-2 and was used to construct GFP-labeled strain NCD-2. The GFP-labeled strain NCD-2 showed strong green fluorescence under planktonic cells and biofilm formation.

Heat-Stable Antifungal Factor (HSAF) Biosynthesis in Lysobacter enzymogenes Is Controlled by the Interplay of Two Transcription Factors and a Diffusible Molecule.

is a Gram-negative, environmentally ubiquitous bacterium that produces a secondary metabolite, called heat-stable antifungal factor (HSAF), as an antifungal factor against plant and animal fungal pathogens. 4-Hydroxybenzoic acid (4-HBA) is a newly identified diffusible factor that regulates HSAF synthesis via LysR (LysR), an LysR-type transcription factor (TF). Here, to identify additional TFs within the 4-HBA regulatory pathway that control HSAF production, we reanalyzed the LenB2-based transcriptomic data, in which LenB2 is the enzyme responsible for 4-HBA production.

SERS Assay for Copper(II) Ions Based on Dual Hot-Spot Model Coupling with MarR Protein: New Cu-Specific Biorecognition Element.

We have developed a rapid and ultrasensitive surface-enhanced Raman scattering (SERS) assay for Cu detection using the multiple antibiotic resistance regulator (MarR) as specific bridging molecules in a SERS hot-spot model. In the assay, Cu induces formation of MarR tetramers, which provide Au nanoparticle (NP)-AuNP bridges, resulting in the formation of SERS hot spots. 4-Mercaptobenzoic acid (4-MBA) was used as a Raman reporter.

Multipath colourimetric assay for copper(II) ions utilizing MarR functionalized gold nanoparticles.

We use the multiple antibiotic resistance regulator (MarR), as a highly selective biorecognition elements in a multipath colourimetric sensing strategy for the fast detection of Cu in water samples. The colourimetric assay is based on the aggregation of MarR-coated gold nanoparticles in the presence of Cu ions, which induces a red-to-purple colour change of the solution. The colour variation in the gold nanoparticle aggregation process can be used for qualitative and quantitative detection of Cu by the naked eye, and with UV-vis and smartphone-based approaches.

4-Hydroxybenzoic acid is a diffusible factor that connects metabolic shikimate pathway to the biosynthesis of a unique antifungal metabolite in Lysobacter enzymogenes.

Heat-stable antifungal factor (HSAF) produced by Lysobacter enzymogenes is a potential lead compound for developing new antibiotics. Yet, how L. enzymogenes regulates the HSAF biosynthesis remains largely unknown.

Lysobacter PilR, the Regulator of Type IV Pilus Synthesis, Controls Antifungal Antibiotic Production via a Cyclic di-GMP Pathway.

is a ubiquitous soil gammaproteobacterium that produces a broad-spectrum antifungal antibiotic, known as heat-stable antifungal factor (HSAF). To increase HSAF production for use against fungal crop diseases, it is important to understand how HSAF synthesis is regulated. To gain insights into transcriptional regulation of the HSAF synthesis gene cluster, we generated a library with deletion mutations in the genes predicted to encode response regulators of the two-component signaling systems in strain OH11.

Transcriptomic analysis reveals new regulatory roles of Clp signaling in secondary metabolite biosynthesis and surface motility in Lysobacter enzymogenes OH11.

Lysobacter enzymogenes is a bacterial biological control agent emerging as a new source of antibiotic metabolites, such as heat-stable antifungal factor (HSAF) and the antibacterial factor WAP-8294A2. The regulatory mechanism(s) for antibiotic metabolite biosynthesis remains largely unknown in L. enzymogenes.