De novo arginine synthesis is required for full virulence of Xanthomonas arboricola pv. juglandis during Walnut Bacterial Blight Disease

2021 ◽  
Author(s):  
Cintia H.D. Sagawa ◽  
Renata De A.B. Assis ◽  
Paulo A. Zaini ◽  
Houston Saxe ◽  
Phillip A. Wilmarth ◽  
...  

Walnut blight (WB) disease caused by Xanthomonas arboricola pv. juglandis (Xaj) threatens orchards worldwide. Nitrogen metabolism in this bacterial pathogen is dependent on arginine, a nitrogen enriched amino acid that can either be synthesized or provided by the plant host. The arginine biosynthetic pathway uses argininosuccinate synthase (argG), associated with increased bacterial virulence. We examined the effects of bacterial arginine and nitrogen metabolism on the plant response during WB by proteomic analysis of the mutant strain Xaj argG-. Phenotypically, the mutant strain produced 42% fewer symptoms and survived in the plant tissue with 2.5-fold reduced growth compared to wild-type (WT) while auxotrophic for arginine in vitro. Proteomic analysis of infected tissue enabled the profiling of 676 Xaj proteins and 3,296 walnut proteins using isobaric labeling in a data-dependent acquisition approach. Comparative analysis of differentially expressed proteins revealed distinct plant responses. Xaj WT triggered processes of catabolism and oxidative stress in the host under observed disease symptoms, while most host’s biosynthetic processes triggered by Xaj WT were inhibited during Xaj argG- infection. Overall, the Xaj proteins revealed a drastic shift in carbon and energy management induced by disruption of nitrogen metabolism while the top differentially expressed proteins included a Fis transcriptional regulator and a peptidyl-prolyl isomerase. Our results show the critical role of de novo arginine biosynthesis to sustain virulence and minimal growth during WB. This study is timely and critical as current copper-based control methods are losing their effectiveness, and new sustainable methods are urgently needed in orchard environments.

2020 ◽  
Vol 17 ◽  
Author(s):  
Qian Lu ◽  
Hai-Zhu Xing ◽  
Nian-Yun Yang

Background: CCl4 acute liver injury (ALI) is a classical model for experimental research. However, there are few reports involved in the fundamental research of CCl4-induced ALI Ligustri Lucidi Fructus (LLF) are and its prescription have been used to treat hepatitis illness clinically. LLF and its active ingredients displayed anti-hepatitis effects, but the mechanism of function has not been fully clarified Objective: To investigate the proteomic analysis of CCl4-induced ALI, and examine the effects of active total glycosides (TG) from LLF on ALI of mice4, including histopathological survey and proteomic changes of liver tissues, and delineate the possible underlying mechanism. Methods: CCl4 was used to produce ALI mice model. The model mice were intragastrically administrated with TG and the liver his-topathological changes of mice were examined. At the end of test, mice liver samples were collected, after protein denaturation, re-duction, desalination and enzymatic hydrolysis, identification was carried out by nano LC-ESI-OrbiTrap MS/MS technology. The data was processed by Maxquant software. The differentially-expressed proteins were screened and identified, and their biological information was also analyzed based on GO and KEGG analysis. Key protein expression was validated by Western blot analysis Results: A total of 705 differentially-expressed proteins were identified during the normal, model and administration group. 9 signifi-cant differential proteins were focused based on analysis. Liver protein expression changes of CCl4-induced ALI mice were mainly involved in several important signal channels, namely FoxO signaling pathway, autophagy-animal, insulin signaling pathway. TG has anti-liver damnification effect in ALI mice, the mechanism of which is related to FoxO1 and autophagy pathways Conclusion: CCl4 inhibited expression of insulin-Like growth factor 1 (Igf1) and 3-phosphoinositide-dependent protein kinase 1 (Pdpk1) in liver cells and induced insulin resistance, thus interfered with mitochondrial autophagy and regeneration of liver cells and the metabolism of glucose and lipid, and caused hepatic necrosis in mice. TG resisted liver injury in mice. TG adjusted the expression level of key proteins Igf1 and Pdpk1 after liver injury and improved insulin resistance, thus promoted autophagy and resisted the liver damage


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Huiyi Song ◽  
Ni Lou ◽  
Jianjun Liu ◽  
Hong Xiang ◽  
Dong Shang

Abstract Background Escherichia coli (E. coli) is the principal pathogen that causes biofilm formation. Biofilms are associated with infectious diseases and antibiotic resistance. This study employed proteomic analysis to identify differentially expressed proteins after coculture of E. coli with Lactobacillus rhamnosus GG (LGG) microcapsules. Methods To explore the relevant protein abundance changes after E. coli and LGG coculture, label-free quantitative proteomic analysis and qRT-PCR were applied to E. coli and LGG microcapsule groups before and after coculture, respectively. Results The proteomic analysis characterised a total of 1655 proteins in E. coli K12MG1655 and 1431 proteins in the LGG. After coculture treatment, there were 262 differentially expressed proteins in E. coli and 291 in LGG. Gene ontology analysis showed that the differentially expressed proteins were mainly related to cellular metabolism, the stress response, transcription and the cell membrane. A protein interaction network and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis indicated that the differentiated proteins were mainly involved in the protein ubiquitination pathway and mitochondrial dysfunction. Conclusions These findings indicated that LGG microcapsules may inhibit E. coli biofilm formation by disrupting metabolic processes, particularly in relation to energy metabolism and stimulus responses, both of which are critical for the growth of LGG. Together, these findings increase our understanding of the interactions between bacteria under coculture conditions.


Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5311
Author(s):  
Fawaz Alasmari ◽  
Sary Alsanea ◽  
Assim A. Alfadda ◽  
Ibrahim O. Alanazi ◽  
Mohthash Musambil ◽  
...  

Cannabis use has been growing recently and it is legally consumed in many countries. Cannabis has a variety of phytochemicals including cannabinoids, which might impair the peripheral systems responses affecting inflammatory and immunological pathways. However, the exact signaling pathways that induce these effects need further understanding. The objective of this study is to investigate the serum proteomic profiling in patients diagnosed with cannabis use disorder (CUD) as compared with healthy control subjects. The novelty of our study is to highlight the differentially changes proteins in the serum of CUD patients. Certain proteins can be targeted in the future to attenuate the toxicological effects of cannabis. Blood samples were collected from 20 male individuals: 10 healthy controls and 10 CUD patients. An untargeted proteomic technique employing two-dimensional difference in gel electrophoresis coupled with mass spectrometry was employed in this study to assess the differentially expressed proteins. The proteomic analysis identified a total of 121 proteins that showed significant changes in protein expression between CUD patients (experimental group) and healthy individuals (control group). For instance, the serum expression of inactive tyrosine protein kinase PEAK1 and tumor necrosis factor alpha-induced protein 3 were increased in CUD group. In contrast, the serum expression of transthyretin and serotransferrin were reduced in CUD group. Among these proteins, 55 proteins were significantly upregulated and 66 proteins significantly downregulated in CUD patients as compared with healthy control group. Ingenuity pathway analysis (IPA) found that these differentially expressed proteins are linked to p38MAPK, interleukin 12 complex, nuclear factor-κB, and other signaling pathways. Our work indicates that the differentially expressed serum proteins between CUD and control groups are correlated to liver X receptor/retinoid X receptor (RXR), farnesoid X receptor/RXR activation, and acute phase response signaling.


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