imagine (Institute of molecular genetics and genetic engineering)
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Decarbonylation of Aromatic Aldehydes and Dehalogenation of Aryl Halides Using Maghemite-Supported Palladium Catalyst
No full textA facile decarbonylation reaction of a variety of aromatic and heteroaromatic aldehydes using maghemite-supported palladium catalyst has been developed. The magnetic properties of catalyst facilitated an easy and efficient recovery of the catalyst from the reaction mixture using an external magnet. It was found that the catalyst could be reused up to four consecutive catalytic runs without a significant change in activity. In addition, the catalyst was also very effective in the dehalogenation of aryl halides. This is the first report on efficient utilization of directly immobilized Pd on maghemite in decarbonylation and dehalogenation reactions.Supporting Information: [https://imagine.imgge.bg.ac.rs/handle/123456789/2815
Class III peroxidases: Functions, localization and redox regulation of isoenzymes
No full textClass III peroxidases (POXs; EC. 1.11.1.7), are secretory, multifunctional plant enzymes that catalyze the oxidation of a variety of substrates by hydrogen peroxide (H2O2). They show a remarkable diversity of isoenzymes, are encoded by a large number of paralogous genes, and are involved in a broad range of metabolic processes throughout plant growth and development. Peroxidases isoenzymes are located in the cell wall, apoplast and vacuole, and may be either soluble or ionically and covalently cell wall bound. They are involved in cell wall cross-linking and loosening, lignification and suberization, auxin catabolism and secondary metabolism. Due to their ability to control the levels of reactive oxygen species (ROS), POXs are efficient components of the antioxidative system induced in response to environmental stress, such as pathogen attack, metal excess, salinity, drought and high light intensity. In addition to the peroxidative function, POXs can catalyze H2O2 production in the oxidative cycle. Peroxidases are responsible either for cell elongation or cell wall stiffening, affecting carbon allocation, auxin level and redox homeostasis, which implicates their key role as being in the regulation of growth and defence under stress condition. This chapter will discuss novel insights into the functions of PODs with special emphasis on their localization, substrate specificity and the regulation of redox homeostasis
Association between the-174 C/G polymorphism in the interleukin-6 (IL-6) gene and gastrointestinal involvement in patients with systemic sclerosis
No full textGenetic predisposition to systemic sclerosis (SSc) has still not been fully revealed. Interleukin-6 (IL-6) is a mediator of T cell proliferation and fibrotic events in SSc. Polymorphisms in the IL-6 are found to be important in susceptibility to development of SSc. We aimed to assess the frequency of -174 C/G of IL-6 gene polymorphism in SSc patients and healthy controls, as well as correlation with disease manifestations. In the case-control study, 102 patients with SSc and 93 controls were included. PCR-RFLP method was performed for genotyping promotor variants -174 C/G of IL-6 gene. The expression level of IL-6 was determined by qRT-PCR on subset of 50 patients and 13 healthy controls with different IL-6 genotypes. We used UCLA GIT 2.0 questionnaire to assess gastrointestinal involvement in SSc patients. The expression level of IL-6 gene was significantly higher in patients with SSc in comparison with healthy controls (p lt 0.05). Carriers of C-allele of IL-6 gene compared to those with G allele, showed higher expression of IL-6 gene (95.8 vs. 41.2, p lt 0.05), higher GIT total score (0.85 vs. 0.5, p lt 0.05) and higher distension scale score (1.4 +/- 0.9 vs. 0.78 +/- 0.8, p = 0.05). No significant differences in genotype distribution and allele frequency were observed between patients and controls. The expression of IL6 gene varies significantly during the course of SSc. The IL-6 gene variant -174 C/G (presence of C-allele) is associated with higher IL-6 gene expression and greater GIT impairment in patients with SSc
Acinetobacter spp. porin Omp33-36: Classification and transcriptional response to carbapenems and host cells
Get PDFAcinetobacter baumannii has been recognized as one of the most challeging pathogens in clinical settings worldwide. Outer membrane porins play a significant role in Acinetobacter antibiotic resistance and virulence. A. baumannii carbapenem resistance and virulence factor porin Omp33-36 was the subject of this study. We investigated the omp33-36 gene transcriptional response in the growth phase, its response to carbapenems, and the effect of contact with host cells. Additionally, the cytotoxic effect of A. baumannii towards keratinocytes was assessed, as well as correlation between omp33-36 gene transcription and cytotoxicity. Further, Acinetobacter spp. Omp33-36 was classified and its characteristics relevant for vaccine candidature were determined. The level of the omp33-36 gene transcription varied between growth phases, but a common pattern could not be established among different strains. Treatment with subinhibitory concentrations of carbapenems decreased, while contact with keratinocytes increased omp33-36 expression in the analysed A. baumannii strains. Variations in omp33-36 mRNA levels did not correlate with cytotoxicity levels. Decrease of omp33-36 mRNA during treatment with subinhibitory concentrations of carbapenems, indicated the importance of transcriptional changes in reversible resistance to carbapenems due to the absence of Omp33-36. The transcription of omp33-36 increased after contact with keratinocytes, indicating the important role of de novo transcription during the initial phase of A. baumannii infection. Primary structural analysis of Acinetobacter spp. Omp33-36 revealed three distinct groups (among four A. baumannii variants). Although we have shown that Omp33-36 was highly polymorphic, we propose a potential antigen (PLAEAAFL motif) for vaccine development. According to PROVEAN analysis, the highly polymorphic structure of Omp33-36 porin should not influence its function significantly
Pharmacotranscriptomic Biomarkers in Glucocorticoid Treatment of Pediatric Inflammatory Bowel Disease
No full textBackground: Pharmacotranscriptomics aims to reach more accurate drug dosing based on interindividual transcriptome variations. Here, we provide an overview of RNA biomarkers that could predict the response to glucocorticoids (GCs), considered the standard for treatment of inflammatory bowel diseases (IBD), both in adult and pediatric patients. Although new biological agents are very effective in IBD treatment, GCs are still widely used for induction of remission in patients with moderate to severe disease. It is important to identify patients that are poor responders to GCs therapy, because suboptimal response is frequent and associated with various side effects. A number of genetic variants related to GC mechanism of action has been studied. However, the majority of reported associations are not consistent. In this regard, pharmacogenomic research is now exploring the world of RNAs. An appropriate regulation of the transcriptome, which mainly comprises mRNAs and non-coding RNAs that control gene expression, has a strong impact in the modulation of GC activity. Aim: The aim of this review is to present the current knowledge of the role of the transcriptome in modulating GC response in pediatric IBD. Results: We will discuss the available literature, concerning the development of pharmacotranscriptomic biomarkers, focusing particularly on non-coding RNAs, and present the results in this field that elucidate a concrete benefit of translating the knowledge gained in the "omics" studies into clinical practice
Physiological and cell ultrastructure disturbances in wheat seedlings generated by Chenopodium murale hairy root exudate
No full textChenopodium murale L. is an invasive weed species significantly interfering with wheat crop. However, the complete nature of its allelopathic influence on crops is not yet fully understood. In the present study, the focus is made on establishing the relation between plant morphophysiological changes and oxidative stress, induced by allelopathic extract. Phytotoxic medium of C. murale hairy root clone R5 reduced the germination rate (24% less than control value) of wheat cv. Nataa seeds, as well as seedling growth, diminishing shoot and root length significantly, decreased total chlorophyll content, and induced abnormal root gravitropism. The R5 treatment caused cellular structural abnormalities, reflecting on the root and leaf cell shape and organization. These abnormalities mostly included the increased number of mitochondria and reorganization of the vacuolar compartment, changes in nucleus shape, and chloroplast organization and distribution. The most significant structural changes were observed in cell wall in the form of amoeboid protrusions and folds leading to its irregular shape. These structural alterations were accompanied by an oxidative stress in tissues of treated wheat seedlings, reflected as increased level of H2O2 and other ROS molecules, an increase of radical scavenging capacity and total phenolic content. Accordingly, the retardation of wheat seedling growth by C. murale allelochemicals may represent a consequence of complex activity involving both cell structure alteration and physiological processes
Silicon mediates sodium transport and partitioning in maize under moderate salt stress
Get PDFSilicon (Si) is known to alleviate salt stress in various crops; however, the influence of Si on sodium (Na) transport and partitioning at the tissue, cell and organelle levels is poorly understood. Maize (Zea mays L.) hybrid sensitive to salt stress was exposed to moderate salt stress (40 mM NaCl; simulating conditions in salinized agricultural soils) without or with supply of 1.5 mM Si(OH)(4). We investigated the expression of SOS genes encoding Na+ efflux transporter in various root tissues of maize, paralleled by measurements of tissue Na concentration. In addition, subcellular localization of Na (using Na fluorescent dye) within the leaf mesophyll cells was also performed. Silicon supplied plants accumulate less Na in both root apex and cortex, but allocate more Na+ to the leaves via the xylem. This was accompanied by increased expression of ZrnSOS1 and ZmSOS2 in the root apex and cortex facilitating Na+ exclusion, and in the root stele for enhanced Na+ loading into the xylem. Also, Si down-regulated the expression of ZmHKT1 in the root stele, which further decreased Na+ unloading from the xylem. Consequently, Si increased accumulation of Na in leaves, but also enhances sequestration of Na+ into the vacuoles thereby decreasing Na+ accumulation in the chloroplasts. In response to moderate salt stress in maize, Si shifts the typical glycophyte behavior of this species towards that of halophytes.This is the peer reviewed vesrion of the article: Bosnić, P., Bosnić, D., Jasnić, J.,& Nikolić, M.. (2018). Silicon mediates sodium transport and partitioning in maize under moderate salt stress. in Environmental and Experimental Botany
Pergamon-Elsevier Science Ltd, Oxford., 155, 681-687.
[https://doi.org/10.1016/j.envexpbot.2018.08.018][https://www.sciencedirect.com/science/article/abs/pii/S0098847218309493?via%3Dihub
Biosynthesis of 2-aminooctanoic acid and its use to terminally modify a lactoferricin B peptide derivative for improved antimicrobial activity
No full textTerminal modification of peptides is frequently used to improve their hydrophobicity. While N-terminal modification with fatty acids (lipidation) has been reported previously, C-terminal lipidation is limited as it requires the use of linkers. Here we report the use of a biocatalyst for the production of an unnatural fatty amino acid, (S)-2-aminooctanoic acid (2-AOA) with enantiomeric excess gt 98% ee and the subsequent use of 2-AOA to modify and improve the activity of an antimicrobial peptide. A transaminase originating from Chromobacterium violaceum was employed with a conversion efficiency 52-80% depending on the ratio of amino group donor to acceptor. 2-AOA is a fatty acid with amino functionality, which allowed direct C- and N-terminal conjugation respectively to an antimicrobial peptide (AMP) derived from lactoferricin B. The antibacterial activity of the modified peptides was improved by up to 16-fold. Furthermore, minimal inhibitory concentrations (MIC) of C-terminally modified peptide were always lower than N-terminally conjugated peptides. The C-terminally modified peptide exhibited MIC values of 25 mu g/ml for Escherichia coli, 50 mu g/ml for Bacillus subtilis, 100 mu g/ml for Salmonella typhimurium, 200 mu g/ml for Pseudomonas aeruginosa and 400 mu g/ml for Staphylococcus aureus. The C-terminally modified peptide was the only peptide tested that showed complete inhibition of growth of S. aureus
Distribution of EGFR SNPs-191C/A and 181946G/A in patients with lung cancer depending on smoking status in the Republic of Srpska, Bosnia and Herzegovina
No full textPurpose: To analyze the frequencies of two single nucleotide polymorphisms (SNPs) of EGFR gene, -191C/A and 181946G/A, among lung cancer patients from the Republic of Srpska, Bosnia and Hercegovina, as well as to assess the association of SNP genotypes with the cancer type and other demographic characteristics of patients, particularly with the smoking status. Methods: This study enrolled 41 lung cancer patients from the territory of Republic Srpska, Bosnia and Herzegovina. Detection EGFR SNPs was performed using PCR-RFLP methodology. PCR was performed on 2720 Thermal Cycler (Applied Biosystems, United States). PCR, as well as RFLP products, were detected by gel electrophoresis. SPSS-17 soft-ware (SPSS, Inc.) was used for statistical analyses. Results: There was significantly more male than female smokers in our cohort (p=0.006). In addition, the proportion of smokers was higher among patients with adenocarcinoma in comparison to patients with other lung cancer types p=0.044). Adenocarcinoma was less common in patients older than 64 years (p=0.035). The wild type homozygous genotype of both SNPs was the most frequent genotype in all the tested demographic groups. Using dominant genetic model for -191C/A SNP, we observed statistically significant association of -191CC genotype and adenocarcinoma (p=0.043) in the subgroup of patients younger than 64 years. Namely, patients younger than 64 years and carriers of -191CC genotype had higher risk (odds ratio/OR=9.6; 95% confidence interval/CI=0.8477 to 108.7214) for adenocarcinoma than the ones carrying -191CA or -191AA genotype. Conclusions: Patients younger than 64 years and carriers of -191CC genotype have significantly higher risk for adenocarcinoma than carriers of -191CA or -191AA genotype. Further studies on larger cohorts are necessary to evaluate -191C/A SNP as a potential biomarker
Novel 1,3,4-thiadiazole-chalcone hybrids containing catechol moiety: synthesis, antioxidant activity, cytotoxicity and DNA interaction studies
No full textHybrid compounds that combine the 1,3,4-thiadiazole-containing catechol moiety with a chalcone motif were synthesized and examined for their antioxidant activity, cytotoxicity, and DNA-binding activity. A series of thirteen compounds showed strong antioxidant and cytotoxic effects on human acute promyelocytic leukemia HL-60 cells. Several compounds exerted good cytotoxic activities on cervical adenocarcinoma HeLa cells. The treatment of HeLa cells with IC50 and double IC50 concentrations of the compounds 5a, 5c, 5f, and 5m induced a statistically significant increase in the percentage of cells within a subG1 cell cycle phase. The examined compounds caused G2/M cell cycle arrest in HeLa cells. Each of these compounds triggered apoptosis in HeLa cells through activation of caspase-3, the main effector caspase, caspase-8, which is involved in the extrinsic apoptotic pathway, and caspase-9, which is involved in the intrinsic apoptotic pathway. All of the examined compounds decreased the expression levels of MMP2 in HeLa cells and levels of protumorigenic miR-133b. Compounds 5a and 5m lowered the expression level of oncogenic miR-21 in HeLa cells. In addition, compounds 5a, 5f, and 5m decreased the expression levels of oncogenic miR-155 while the treatment of HeLa cells with compounds 5a, 5c, and 5f increased expression of tumor-suppressive miR-206. Observed effects of these compounds on expression levels of four examined miRNAs suggest their prominent cancer-suppressive activity. An investigation by absorption and fluorescence spectroscopy showed more efficient calf thymus DNA binding activity of the compound 5m in comparison to other tested compounds. Results of a pUC19 plasmid cleavage study and comet assay showed DNA damaging activities of compounds 5a and 5c.Peer-reviewed manuscript: [https://imagine.imgge.bg.ac.rs/handle/123456789/1767