scholarly journals Ceruloplasmin-derived peptide is the strongest regulator of oxidative stress and leukotriene synthesis in neutrophils

2017 ◽  
Vol 95 (3) ◽  
pp. 445-449 ◽  
Author(s):  
Ekaterina A. Golenkina ◽  
Alexey D. Livenskyi ◽  
Galina M. Viryasova ◽  
Yulia M. Romanova ◽  
Galina F. Sud’ina ◽  
...  

Ceruloplasmin, an acute-phase protein, can affect the activity of leukocytes through its various enzymatic activities and protein–protein interactions (with lactoferrin, myeloperoxidase, eosinophil peroxidase, serprocidins, and 5-lipoxygenase (5-LOX), among others). However, the molecular mechanisms of ceruloplasmin activity are not clearly understood. In this study, we tested the ability of two synthetic peptides, RPYLKVFNPR (883–892) (P1) and RRPYLKVFNPRR (882–893) (P2), corresponding to the indicated fragments of the ceruloplasmin sequence, to affect neutrophil activation. Leukotriene (LT) B4 is the primary eicosanoid product of polymorphonuclear leukocytes (PMNLs, neutrophils). We studied leukotriene synthesis in PMNLs upon interaction with Salmonella enterica serovar Typhimurium. Priming of neutrophils with phorbol 12-myristate 13-acetate (PMA) elicited the strong regulatory function of P2 peptide as a superoxide formation inducer and leukotriene synthesis inhibitor. Ceruloplasmin-derived P2 peptide appeared to be a strong inhibitor of 5-LOX product synthesis under conditions of oxidative stress.

2018 ◽  
Vol 25 (1) ◽  
pp. 5-21 ◽  
Author(s):  
Ylenia Cau ◽  
Daniela Valensin ◽  
Mattia Mori ◽  
Sara Draghi ◽  
Maurizio Botta

14-3-3 is a class of proteins able to interact with a multitude of targets by establishing protein-protein interactions (PPIs). They are usually found in all eukaryotes with a conserved secondary structure and high sequence homology among species. 14-3-3 proteins are involved in many physiological and pathological cellular processes either by triggering or interfering with the activity of specific protein partners. In the last years, the scientific community has collected many evidences on the role played by seven human 14-3-3 isoforms in cancer or neurodegenerative diseases. Indeed, these proteins regulate the molecular mechanisms associated to these diseases by interacting with (i) oncogenic and (ii) pro-apoptotic proteins and (iii) with proteins involved in Parkinson and Alzheimer diseases. The discovery of small molecule modulators of 14-3-3 PPIs could facilitate complete understanding of the physiological role of these proteins, and might offer valuable therapeutic approaches for these critical pathological states.


PLoS ONE ◽  
2014 ◽  
Vol 9 (4) ◽  
pp. e95271 ◽  
Author(s):  
David T. Fox ◽  
Emily N. Schmidt ◽  
Hongzhao Tian ◽  
Suraj Dhungana ◽  
Michael C. Valentine ◽  
...  

2008 ◽  
Vol 412 (1) ◽  
pp. 163-170 ◽  
Author(s):  
Alon Herschhorn ◽  
Iris Oz-Gleenberg ◽  
Amnon Hizi

The RT (reverse transcriptase) of HIV-1 interacts with HIV-1 IN (integrase) and inhibits its enzymatic activities. However, the molecular mechanisms underling these interactions are not well understood. In order to study these mechanisms, we have analysed the interactions of HIV-1 IN with HIV-1 RT and with two other related RTs: those of HIV-2 and MLV (murine-leukaemia virus). All three RTs inhibited HIV-1 IN, albeit to a different extent, suggesting a common site of binding that could be slightly modified for each one of the studied RTs. Using surface plasmon resonance technology, which monitors direct protein–protein interactions, we performed kinetic analyses of the binding of HIV-1 IN to these three RTs and observed interesting binding patterns. The interaction of HIV-1 RT with HIV-1 IN was unique and followed a two-state reaction model. According to this model, the initial IN–RT complex formation was followed by a conformational change in the complex that led to an elevation of the total affinity between these two proteins. In contrast, HIV-2 and MLV RTs interacted with IN in a simple bi-molecular manner, without any apparent secondary conformational changes. Interestingly, HIV-1 and HIV-2 RTs were the most efficient inhibitors of HIV-1 IN activity, whereas HIV-1 and MLV RTs showed the highest affinity towards HIV-1 IN. These modes of direct protein interactions, along with the apparent rate constants calculated and the correlations of the interaction kinetics with the capacity of the RTs to inhibit IN activities, are all discussed.


2021 ◽  
Vol 72 (3) ◽  
pp. 30-36
Author(s):  
Tatjana Simić

Studies of the molecular mechanisms regarding interaction of different viruses with receptors on the host cell surface have shown that the viral entry depends on the specific relationship between free thiol (SH) groups and disulfides on the virus surface, as well as the thiol disulfide balance on the host cell surface. The presence of oxidizing compounds or alkylating agents, which disturb the thiol-disulfide balance on the surface of the virus, can also affect its infectious potential. Disturbed thiol-disulfide balance may also influence protein-protein interactions between SARS-CoV-2 protein S and ACE2 receptors of the host cell. This review presents the basic mechanisms of maintaining intracellular and extracellular thiol disulfide balance and previous experimental and clinical evidence in favor of impaired balance in SARS-CoV-2 infection. Besides, the results of the clinical application or experimental analysis of compounds that induce changes in the thiol disulfide balance towards reduction of disulfide bridges in proteins of interest in COVID-19 infection are presented.


Author(s):  
Meng-Ke Zhang ◽  
Meng-Yao Zhang ◽  
Shuo-Bo Liu ◽  
Ying-Ying Yang ◽  
Ya-Jun Zhai ◽  
...  

Abstract Background The increasing use of colistin causes a serious breach in our last line of defence against MDR Gram-negative pathogens. Our previous study showed that CpxR overexpression increases the susceptibility of acrB and cpxR double-deleted Salmonella enterica serovar Typhimurium to colistin. Objectives To identify the mechanism of CpxAR and efflux pumps that synergistically enhance the susceptibility of S. Typhimurium to colistin. Methods A series of cpxR- and tolC-deleted mutants and a cpxR-complemented strain from a multidrug-susceptible standard strain of S. Typhimurium (JS) were generated in our previous study. Herein, we investigated the susceptibility of these strains to colistin through the broth microdilution method, time–kill curves and survival assays. Growth curves were measured by OD600 in LB broth, tryptone-soy broth (TSB) and M9-glucose (0.2%) minimal media. Finally, molecular mechanisms underlying the mode of action were elucidated by transcriptomic analysis. Results We found that in contrast to JS (0.8 mg/L), the MIC of colistin for JSΔtolC::kan showed a 16-fold decrease (0.05 mg/L). Notably, JSΔcpxRΔtolC and JSΔcpxRΔtolC/pcpxR were associated with a 256-fold decrease (0.0031 mg/L) compared with JS. Growth curves identified that JSΔcpxRΔtolC and JSΔcpxRΔtolC/pcpxR displayed a markedly lower growth rate and poorer adaptability. In addition, time–kill curves and survival assays showed that JSΔcpxRΔtolC and JSΔcpxRΔtolC/pcpxR were more susceptible to colistin. Lastly, double deletion of cpxR and tolC enhanced oxidative damage through promoting oxidative phosphorylation, the tricarboxylic acid (TCA) cycle and trimethylamine N-oxide (TMAO) respiration. Conclusions Our findings revealed that double deletion of cpxR and tolC significantly increases the susceptibility of S. Typhimurium to colistin.


2018 ◽  
Vol 15 (4) ◽  
Author(s):  
Olga V. Saik ◽  
Pavel S. Demenkov ◽  
Timofey V. Ivanisenko ◽  
Elena Yu. Bragina ◽  
Maxim B. Freidin ◽  
...  

AbstractComorbid states of diseases significantly complicate diagnosis and treatment. Molecular mechanisms of comorbid states of asthma and hypertension are still poorly understood. Prioritization is a way for identifying genes involved in complex phenotypic traits. Existing methods of prioritization consider genetic, expression and evolutionary data, molecular-genetic networks and other. In the case of molecular-genetic networks, as a rule, protein-protein interactions and KEGG networks are used. ANDSystem allows reconstructing associative gene networks, which include more than 20 types of interactions, including protein-protein interactions, expression regulation, transport, catalysis, etc. In this work, a set of genes has been prioritized to find genes potentially involved in asthma and hypertension comorbidity. The prioritization was carried out using well-known methods (ToppGene and Endeavor) and a cross-talk centrality criterion, calculated by analysis of associative gene networks from ANDSystem. The identified genes, including IL1A, CD40LG, STAT3, IL15, FAS, APP, TLR2, C3, IL13 and CXCL10, may be involved in the molecular mechanisms of comorbid asthma/hypertension. An analysis of the dynamics of the frequency of mentioning the most priority genes in scientific publications revealed that the top 100 priority genes are significantly enriched with genes with increased positive dynamics, which may be a positive sign for further studies of these genes.


2020 ◽  
Vol 26 (70) ◽  
pp. 16690-16705
Author(s):  
Francesco Bellia ◽  
Giuseppa Ida Grasso ◽  
Ikhlas Mohamed Mohamud Ahmed ◽  
Valentina Oliveri ◽  
Graziella Vecchio

2020 ◽  
pp. 1-14
Author(s):  
Md. Jahangir Alam ◽  
Md. Alamin ◽  
Most. Humaira Sultana ◽  
Md. Asif Ahsan ◽  
Md. Ripter Hossain ◽  
...  

Abstract Leaf morphology of crop plants has significant value in agronomy. Leaf rolling in rice plays a vital role to increase grain yield. However, collective information on the rolling leaf (RL) genes reported to date and different comparative bioinformatics studies of their sequences are still incomplete. This bioinformatics study was designed to investigate structures, functions and diversifications of the RL related genes reported till now through several studies. We performed different comparative and functional analyses of the selected 42 RL genes among 103 RL genes using different bioinformatics techniques including gene structure, conserved domain, phylogenetic, gene ontology (GO), transcription factor (TF), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein–protein network. Exon-intron organization and conserved domain analysis showed diversity in structures and conserved domains of RL genes. Phylogenetic analysis classified the proteins into five major groups. GO and TF analyses revealed that regulation-related genes were remarkably enriched in biological process and 10 different TF families were involved in rice leaf rolling. KEGG analysis demonstrated that 14 RL genes were involved in the KEGG pathways, among which 50% were involved in the metabolism pathways. Of the selected RL proteins, 55% proteins were non-interacting with other RL proteins and OsRL9 was the most interacting RL protein. These results provide important information regarding structures, conserved domains, phylogenetic revolution, protein–protein interactions and other genetic bases of RL genes which might be helpful to the researchers for functional analysis of new candidate RL genes to explore their characteristics and molecular mechanisms for high yield rice breeding.


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