scholarly journals Transcriptome Analysis on the Mechanism of Ethylicin Inhibiting Pseudomonas syringae pv. actinidiae on Kiwifruit

2021 ◽  
Vol 9 (4) ◽  
pp. 724
Author(s):  
Tao Liu ◽  
Xiaoli Ren ◽  
Guangyun Cao ◽  
Xia Zhou ◽  
Linhong Jin

Bacterial canker disease caused by Pseudomonas syringae pv. actinidiae (Psa) is a devastating disease of kiwifruit, which is severely limiting the development of the kiwifruit industry. Ethylicin is a broad-spectrum plant biomimetic fungicide. However, its application in the control of kiwifruit bacterial canker is rarely reported, and the mechanism of ethylicin on Psa remains unknown. In this study, we investigated the effect of ethylicin on Psa in vitro and in vivo and found that ethylicin can inhibit the growth of Psa and prevent the cankering in the plant stem. Mechanism investigation indicated that ethylicin acted by limiting the movement of Psa, destroying the cell membrane of Psa, and inhibiting the formation of Psa biofilm. In addition, it was also found through transcriptomics research that ethylicin can up-regulate the expression of genes related to protein export and biofilm formation–Pseudomonas aeruginosa and down-regulate the expression of genes related to flagellar assembly in Psa. This study concluded that ethylicin can effectively inhibit Psa growth, and it could help to gain a better understanding of the mechanisms of ethylicin inhibiting Psa and provide practical data for the application of ethylicin as a highly potent agent for controlling the bacterial canker disease of kiwifruit.

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Mustafa Akbaba ◽  
Hatice Ozaktan

Abstract Background Bacterial canker and subsequent gummosis are caused by multiple pathogens and lead to significant yield and productivity losses in sweet cherry cultivation in Turkey. This study identified that Pseudomonas syringae pathovars were responsible for bacterial canker on sweet cherry orchards by using classical and molecular methods and evaluated the biocontrol effects of bacteriophages against P. syringae pv. syringae. Results Pathogenic bacteria were isolated from samples taken from plants showing symptoms of bacterial canker in cherry orchards located in İzmir and Manisa provinces. Specific pathogens were identified using pathogenicity, phenotypic tests, and simplex PCR. Bacteriophages effective against P. syringae strains were isolated from soil contaminated with pathogens identified in the diseased orchards using an optimized isolation protocol. The biocontrol activity of bacteriophage isolates against P. syringae pv. syringae was tested in vitro and in vivo. The results of pathogenicity tests on immature sweet cherry fruits and micropropagated cherry plantlets revealed 10 pathogenic bacteria isolates from 44 plant samples taken from sweet cherry orchards showing symptoms of bacterial canker. Conclusions Ten isolates were identified as Pseudomonas syringae pv. syringae. Nine different pure bacteriophage isolates were effective. The results indicated that bacteriophage isolates may demonstrate variable reactivity against P. syringae pathovars.


2021 ◽  
Vol 9 (6) ◽  
pp. 1328
Author(s):  
Helen C. Neale ◽  
Michelle T. Hulin ◽  
Richard J. Harrison ◽  
Robert W. Jackson ◽  
Dawn L. Arnold

Bacterial canker of Prunus, affecting economically important stone fruit crops including cherry, peach, apricot and plum, is caused by the plant pathogen Pseudomonas syringae (P.s.). Strains from two pathovars—P.s. pv. syringae (Pss) and P.s. pv. morsprunorum race 1 (PsmR1) and 2 (PsmR2)—in three phylogenetically distant clades have convergently evolved to infect Prunus. The bacteria enter woody tissues through wounds and leaf scars, causing black necrotic cankers. Symptoms are also produced on blossom, fruit and leaves. Little is known about the mechanisms P.s. uses to colonise tree hosts such as Prunus. Here, we created transposon (Tn) mutant libraries in one strain of P.s. from each of the three clades and screened the mutants on immature cherry fruit to look for changes in virulence. Mutants (242) with either reduced or enhanced virulence were detected and further characterised by in vitro screens for biofilm formation, swarming ability, and pathogenicity on leaves and cut shoots. In total, 18 genes affecting virulence were selected, and these were involved in diverse functions including motility, type III secretion, membrane transport, amino acid synthesis, DNA repair and primary metabolism. Interestingly, mutation of the effector gene, hopAU1, led to an increase in virulence of Psm R2.


Antibiotics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 554
Author(s):  
Yu-Rim Song ◽  
Nguyen Trung Vu ◽  
Jungkum Park ◽  
In Sun Hwang ◽  
Hyeon-Ju Jeong ◽  
...  

Pseudomonas syringae pv. actinidiae (Psa) is a Gram-negative bacterium that causes bacterial canker disease in kiwifruit. Copper or antibiotics have been used in orchards to control this disease, but the recent emergence of antibiotic-resistant Psa has called for the development of a new control agent. We previously reported that the bacteriophage (or phage) PPPL-1 showed antibacterial activity for both biovar 2 and 3 of Psa. To investigate the possibility of PPPL-1 to control bacterial canker in kiwifruit, we further tested the efficacy of PPPL-1 and its phage cocktail with two other phages on suppressing disease development under greenhouse conditions using 6 weeks old kiwifruit plants. Our results showed that the disease control efficacy of PPPL-1 treatment was statistically similar to those of phage cocktail treatment or AgrimycinTM, which contains streptomycin and oxytetracycline antibiotics as active ingredients. Moreover, PPPL-1 could successfully kill streptomycin-resistant Psa isolates, of which the treatment of BuramycinTM carrying only streptomycin as an active ingredient had no effect in vitro. The phage PPPL-1 was further characterized, and stability assays showed that the phage was stable in the field soil and at low temperature of 0 ± 2 °C. In addition, the phage could be scaled up quickly up to 1010 pfu/mL at 12 h later from initial multiplicity of infection of 0.000005. Our results indicate that PPPL-1 phage is a useful candidate as a biocontrol agent and could be a tool to control the bacterial canker in kiwifruit by Psa infection in the field conditions.


2021 ◽  
Vol 60 (2) ◽  
pp. 215-228
Author(s):  
Enrico BIONDI ◽  
Lorenzo GALLIPOLI ◽  
Angelo MAZZAGLIA ◽  
Set Perez FUENTEALBA ◽  
Nemanja KUZMANOVIĆ ◽  
...  

Pseudomonas syringae pv. actinidiae is an important pathogen of kiwifruit (Actinidia deliciosa), and bacterial canker of this host is managed by monitoring and chemical control strategies. The efficacy of the bio-pesticides Amylo-X® (based on Bacillus amyloliquefaciens subsp. plantarum strain D747) and Serenade Max® (strain QST713 of B. subtilis) was evaluated by in vitro and in vivo experiments. Both antagonists inhibited different biovars of the pathogen in in vitro assays; QST713 was more efficient than D747. The two Bacillus strains also colonized A. deliciosa flowers (c. 105-7 cfu per flower) up to 96 h after inoculation. D747 persisted on leaves (c. 104-6 cfu cm-2) up to 4 weeks after inoculation, during 2 years in Emilia Romagna and Latium regions of Italy. On flowers, the antagonists reduced pathogen populations, compared to untreated (control) flowers. On A. deliciosa and A. chinensis plants under controlled conditions, Amylo-X® reduced severity of bacterial canker, providing ca. 50% relative protection on A. deliciosa and 70% on A. chinensis. Serenade Max® was less effective, giving 0% relative protection on A. deliciosa and 40% on A. chinensis. In a field trial, on A. deliciosa plants, Amylo-X® reduced the severity of bacterial canker on leaves, providing ca. 40% relative protection. The sensitivity of both antagonistic strains to streptomycin sulphate was confirmed by testing the most used concentration where antibiotics are approved for management of bacterial pathogens.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Poushali Chakraborty ◽  
Sapna Bajeli ◽  
Deepak Kaushal ◽  
Bishan Dass Radotra ◽  
Ashwani Kumar

AbstractTuberculosis is a chronic disease that displays several features commonly associated with biofilm-associated infections: immune system evasion, antibiotic treatment failures, and recurrence of infection. However, although Mycobacterium tuberculosis (Mtb) can form cellulose-containing biofilms in vitro, it remains unclear whether biofilms are formed during infection in vivo. Here, we demonstrate the formation of Mtb biofilms in animal models of infection and in patients, and that biofilm formation can contribute to drug tolerance. First, we show that cellulose is also a structural component of the extracellular matrix of in vitro biofilms of fast and slow-growing nontuberculous mycobacteria. Then, we use cellulose as a biomarker to detect Mtb biofilms in the lungs of experimentally infected mice and non-human primates, as well as in lung tissue sections obtained from patients with tuberculosis. Mtb strains defective in biofilm formation are attenuated for survival in mice, suggesting that biofilms protect bacilli from the host immune system. Furthermore, the administration of nebulized cellulase enhances the antimycobacterial activity of isoniazid and rifampicin in infected mice, supporting a role for biofilms in phenotypic drug tolerance. Our findings thus indicate that Mtb biofilms are relevant to human tuberculosis.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Amber R Paulson ◽  
Maureen O’Callaghan ◽  
Xue-Xian Zhang ◽  
Paul B Rainey ◽  
Mark R H Hurst

Abstract The function of microbes can be inferred from knowledge of genes specifically expressed in natural environments. Here, we report the in vivo transcriptome of the entomopathogenic bacterium Yersinia entomophaga MH96, captured during initial, septicemic, and pre-cadaveric stages of intrahemocoelic infection in Galleria mellonella. A total of 1285 genes were significantly upregulated by MH96 during infection; 829 genes responded to in vivo conditions during at least one stage of infection, 289 responded during two stages of infection, and 167 transcripts responded throughout all three stages of infection compared to in vitro conditions at equivalent cell densities. Genes upregulated during the earliest infection stage included components of the insecticidal toxin complex Yen-TC (chi1, chi2, and yenC1), genes for rearrangement hotspot element containing protein yenC3, cytolethal distending toxin cdtAB, and vegetative insecticidal toxin vip2. Genes more highly expressed throughout the infection cycle included the putative heat-stable enterotoxin yenT and three adhesins (usher-chaperone fimbria, filamentous hemagglutinin, and an AidA-like secreted adhesin). Clustering and functional enrichment of gene expression data also revealed expression of genes encoding type III and VI secretion system-associated effectors. Together these data provide insight into the pathobiology of MH96 and serve as an important resource supporting efforts to identify novel insecticidal agents.


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Pei-Yao Liu ◽  
Cheng-Cheung Chen ◽  
Chia-Ying Chin ◽  
Te-Jung Liu ◽  
Wen-Chiuan Tsai ◽  
...  

AbstractIn obese adults, nonalcoholic fatty liver disease (NAFLD) is accompanied by multiple metabolic dysfunctions. Although upregulated hepatic fatty acid synthesis has been identified as a crucial mediator of NAFLD development, the underlying mechanisms are yet to be elucidated. In this study, we reported upregulated expression of gene related to anergy in lymphocytes (GRAIL) in the livers of humans and mice with hepatic steatosis. Grail ablation markedly alleviated the high-fat diet-induced hepatic fat accumulation and expression of genes related to the lipid metabolism, in vitro and in vivo. Conversely, overexpression of GRAIL exacerbated lipid accumulation and enhanced the expression of lipid metabolic genes in mice and liver cells. Our results demonstrated that Grail regulated the lipid accumulation in hepatic steatosis via interaction with sirtuin 1. Thus, Grail poses as a significant molecular regulator in the development of NAFLD.


2007 ◽  
Vol 6 (6) ◽  
pp. 931-939 ◽  
Author(s):  
Fang Li ◽  
Michael J. Svarovsky ◽  
Amy J. Karlsson ◽  
Joel P. Wagner ◽  
Karen Marchillo ◽  
...  

ABSTRACT Candida albicans is the leading cause of systemic fungal infections in immunocompromised humans. The ability to form biofilms on surfaces in the host or on implanted medical devices enhances C. albicans virulence, leading to antimicrobial resistance and providing a reservoir for infection. Biofilm formation is a complex multicellular process consisting of cell adhesion, cell growth, morphogenic switching between yeast form and filamentous states, and quorum sensing. Here we describe the role of the C. albicans EAP1 gene, which encodes a glycosylphosphatidylinositol-anchored, glucan-cross-linked cell wall protein, in adhesion and biofilm formation in vitro and in vivo. Deleting EAP1 reduced cell adhesion to polystyrene and epithelial cells in a gene dosage-dependent manner. Furthermore, EAP1 expression was required for C. albicans biofilm formation in an in vitro parallel plate flow chamber model and in an in vivo rat central venous catheter model. EAP1 expression was upregulated in biofilm-associated cells in vitro and in vivo. Our results illustrate an association between Eap1p-mediated adhesion and biofilm formation in vitro and in vivo.


Diabetologia ◽  
2021 ◽  
Author(s):  
Yukina Takeichi ◽  
Takashi Miyazawa ◽  
Shohei Sakamoto ◽  
Yuki Hanada ◽  
Lixiang Wang ◽  
...  

Abstract Aims/hypothesis Mitochondria are highly dynamic organelles continuously undergoing fission and fusion, referred to as mitochondrial dynamics, to adapt to nutritional demands. Evidence suggests that impaired mitochondrial dynamics leads to metabolic abnormalities such as non-alcoholic steatohepatitis (NASH) phenotypes. However, how mitochondrial dynamics are involved in the development of NASH is poorly understood. This study aimed to elucidate the role of mitochondrial fission factor (MFF) in the development of NASH. Methods We created mice with hepatocyte-specific deletion of MFF (MffLiKO). MffLiKO mice fed normal chow diet (NCD) or high-fat diet (HFD) were evaluated for metabolic variables and their livers were examined by histological analysis. To elucidate the mechanism of development of NASH, we examined the expression of genes related to endoplasmic reticulum (ER) stress and lipid metabolism, and the secretion of triacylglycerol (TG) using the liver and primary hepatocytes isolated from MffLiKO and control mice. Results MffLiKO mice showed aberrant mitochondrial morphologies with no obvious NASH phenotypes during NCD, while they developed full-blown NASH phenotypes in response to HFD. Expression of genes related to ER stress was markedly upregulated in the liver from MffLiKO mice. In addition, expression of genes related to hepatic TG secretion was downregulated, with reduced hepatic TG secretion in MffLiKO mice in vivo and in primary cultures of MFF-deficient hepatocytes in vitro. Furthermore, thapsigargin-induced ER stress suppressed TG secretion in primary hepatocytes isolated from control mice. Conclusions/interpretation We demonstrated that ablation of MFF in liver provoked ER stress and reduced hepatic TG secretion in vivo and in vitro. Moreover, MffLiKO mice were more susceptible to HFD-induced NASH phenotype than control mice, partly because of ER stress-induced apoptosis of hepatocytes and suppression of TG secretion from hepatocytes. This study provides evidence for the role of mitochondrial fission in the development of NASH. Graphical abstract


Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 631
Author(s):  
Mengfan Peng ◽  
Wentao Tong ◽  
Zhen Zhao ◽  
Ling Xiao ◽  
Zhaoyue Wang ◽  
...  

In this experiment, the quorum quenching gene ytnP of Bacillus licheniformis T-1 was cloned and expressed, and the effect against infection of Aeromonas hydrophila ATCC 7966 was evaluated in vitro and vivo. The BLAST results revealed a 99% sequence identity between the ytnP gene of T-1 and its homolog in B.subtilis sub sp. BSP1, and the dendroGram showed that the similarity in the YtnP protein in T-1 was 100% in comparison with B.subtilis 3610, which was categorized as the Aidc cluster of the MBL family. The AHL lactonase activity of the purified YtnP was detected as 1.097 ± 0.7 U/mL with C6-HSL as the substrate. Otherwise, purified YtnP protein could significantly inhibit the biofilm formation of A.hydrophila ATCC 7966 with an inhibition rate of 68%. The MIC of thiamphenicol and doxycycline hydrochloride against A. hydrophila reduced from 4 μg/mL and 0.5 μg/mL to 1 μg/mL and 0.125 μg/mL, respectively, in the presence of YtnP. In addition, YtnP significantly inhibited the expression of five virulence factors hem, ahyB, ast, ep, aerA of A. hydrophila ATCC 7966 as well (p < 0.05). The results of inhibition on virulence showed a time-dependence tendency, while the strongest anti-virulence effects were within 4–24 h. In vivo, when the YtnP protein was co-injected intraperitoneally with A. hydrophila ATCC 7966, it attenuated the pathogenicity of A. hydrophila and the accumulated mortality was 27 ± 4.14% at 96 h, which was significantly lower than the average mortality of 78 ± 2.57% of the Carassius auratus injected with 108 CFU/mL of A. hydrophila ATCC 7966 only (p < 0.001). In conclusion, the AHL lactonase in B. licheniformis T-1 was proven to be YtnP protein and could be developed into an agent against infection of A. hydrophila in aquaculture.


Sign in / Sign up

Export Citation Format

Share Document