Ru(III) kompleksi i njihovi ligandi izvedeni iz salicilaldehida i halogeniranih anilina: sinteza, karakterizacija i antioksidativno djelovanje

This work aimed to describe the synthesis and characterisation of two anionic Ru(III) complexes of the general formula Na[RuCl2(N-4-Cl-Ph-salim)2] and Na[RuCl2(N-3-Br-Ph-salim)2, their associated ligands, and determine their antioxidant activity. The ligands N-4-Cl-phenylsalicylidenimine (N-4-Cl-Ph-salimH, HLa) and N-3-Br-phenylsalicylidenimine (N-3-Br-Ph-salimH, HLb), Schiff bases, were synthesised from salicylaldehyde and chloroaniline or bromoaniline. The compounds were characterised using IR spectroscopy and ESI ToF mass spectrometry. The following was confirmed: coordination of ligands on the Ru(III) centre, the molecular formulas, and the corresponding M– ions: [C26H18N2O2Cl4Ru]–– ion, (m/z: 719.8283). The antioxidant activity was determined by the ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (1,1-diphenyl-2-picrylhydrazyl) assays. In contrast to the ligands, both complexes proved to be strong scavengers of the ABTS and DPPH radicals with IC50 (half maximal inhibitory concentration) values comparable to those of Trolox. As such, they present valuable candidates for further research related to their biological properties.Ovaj rad je imao cilj opisati sintezu i karakterizaciju dvaju anionskih Ru(III) kompleksa općenite formule Na[RuCl2(N-4-Cl-Ph-salim)2] i Na[RuCl2(N-3-Br-Ph-salim)2, njihove pridružene ligande i odrediti njihovu antioksidacijsku aktivnost. Ligandi N-4-Cl-fenilsalicilidenimin (N-4-Cl-Ph-salimH, HLa) i N-3-Br-fenilsalicilidenimin (N-3-Br-Ph-salimH, HLb), Schiffove baze, sintetizirani su iz salicilaldehida i kloranilina ili bromoanilina. Spojevi su karakterizirani primjenom IR spektroskopije i ESI ToF spektrometrije masa. Potvrđena je koordinacija liganada na Ru(III) centru, molekulske formule i odgovarajući M– ioni: [C26H18N2O2Cl4Ru]–– ion (m/z: 719.8283). Antioksidacijska aktivnost određena je metodama ABTS (2,2’-azino-bis(3-etilbenzotiazolin-6-sulfonska kiselina) i DPPH (1,1-difenil-2-pikrilhidrazil). Za razliku od liganda, oba kompleksa pokazala su se jakim hvatačima ABTS i DPPH radikala s IC50 vrijednostima (koncentracija koja postiže 50 % inhibicije) usporedivim s onima od Troloxa. Kao takvi, vrijedni su kandidati za daljnja istraživanja vezana uz njihova biološka svojstva

Effect of the kanamycin resistance marker on stability of 2μ-based expression plasmids

U ovom radu opisan je uticaj gena za kanamicinsku rezistenciju (Kmr) na održavanje 2μm plazmida u Saccharomyces cerevisiae. Prisustvo ovog marker gena dovodi do gubitka stabilnog model-vektora konstantnom stopom nezavisnom od izvora ugljenika i stope rasta kulture. Kod sojeva za sintezu heterolognih proteina sa galaktoznog promotora (GALUAS) uvođenje Kmr rezultira "čišćenjem" od kvaščevih epizomalnih plazmida (YEp) u svega nekoliko generacija. Primena selektivnog pritiska na sojeve koji proizvode rekombinantnu penicilin G amidazu (rPGA) nije dovela do očekivanog povećanja prinosa proteina. Ispitivanjem uticaja samih genetičkih elemenata za proizvodnju heterolognih proteina na stabilnost vektora pokazano je da najjače destabilišuće dejstvo ima prisustvo i eksprecija stranog gena.In this paper we describe the effect of the kanamycin resistance gene (Kmr) on 2μm-based plasmid maintenance in Saccharomyces cerevisiae. The influence of this marker gene on the loss of the stable model-vectors proved to be constant, as well as independent of carbon source and culture growth rates. In strains for GALUAS - driven heterologous protein production introduction of Kmr resulted in curing of the yeast episomal plasmid (YEp) from the population in a small number of generations. Application of selective pressure on the strain producing recombinant penicillin G amidase (rPGA) did not provide the expected increase of protein yield. The influence of genetic elements for heterologous protein production on vector stability was examined, and the most destabilizing factors prove to be the presence and expression of the foreign gene

Antimicrobial and genotoxic activity of novel ruthenium(III) complex with n-phenyl-5-nitrosalicylideneimine

In this study, novel hexa coordinated ruthenium(III) complex of the type Na[RuCl2L2)] (where L = monobasic bidentate Schiff base derived from the condensation of 5-nitrosalicyladehyde with aniline) has been synthesized and characterized by electrospray ionization time-of-flight mass spectrometry, infrared spectroscopy and ultraviolet/visible spectrophotometry. Schiff base N-phenyl-5-nitrosalicylideneimine is coordinated to the ruthenium via imine nitrogen and phenolic oxygen. Mass spectra showed molecular ion (M-) at m/z 653.9641 which corresponds to [C26H18Cl2N4O6Ru]-. The in vitro antimicrobial properties of the Schiff base and the complex were tested by micro-dilution technique and agar plate assay for determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The compounds showed a higher antibacterial activity against tested Gram-positive bacteria (Staphylococcus aureus ATCC 33591 and ATCC 29213), whereas against the Gram-negative bacteria (Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603) were ineffective. The genotoxic effects of Ru(III) complex were investigated using the Cytokinesis Block Micronucleus (CBMN) assay in human lymphocytes cultures. The cell culture treated with the complex at a concentration of 3.7 µg/mL exhibit the most prominent effect of decreasing the frequency of micronucleus for 44%, while at the concentrations of 1.5 and 7.4 µg/mL effect is slightly lower (40%), compared to the control cell culture

Glycosylation and pH stability of penicillin G acylase from providencia rettgeri produced in Pichia pastoris

Penicilin G acilaza (PAC) je jedan od najšire korišćenih enzima u industrijskoj sintezi polusintetskih antibiotika. U ovom radu dobijeni nivo ekspresije PAC gena iz Providencia rettgeri u ekspresionom sistemu Pichia pastoris iznosio je 2.7 U/ml. Rekombinantni enzim je prečišćen i određen je njegov glikozilacioni status. Nađeno je da osim što su obe subjedinice enzima (α i β) N-glikozilovane, β subjedinica sadrži još i O-glikane. Takođe je ustanovljeno da je rekombinantna PACP. rett. stabilna u širokom pH opsegu što ju je, zajedno sa predhodno ustanovljenom visokom termostabilnošću, učinilo izuzetno privlačnim biokatalizatorom sa industrijske tačke gledišta.Penicillin G acylase (PAC) is one of the most widely used enzymes in industrial synthesis of semi-synthetic antibiotics. The Providencia rettgeri pac gene was expressed to a level of 2.7 U/ml using the Pichia pastoris expression system. The recombinant enzyme was purified and its glycosylation status was determined. It was found that both subunits (α and β) of the enzyme were N-glycosylated, while the β-subunit also contained O-glycans. It was also observed that rPACP.rett. was stable in a wide range of pH, which, in addition to the previously proved high thermostability, makes it an attractive biocatalyst from an industrial point of view

Comparative study of anonymization methods on synthetically generated health database

By anonymizing data, we protect the identity of an individual from disclosing sensitive personal information. Hospitals store data on their patients in databases. Many of stored data is used for research purposes. According to the laws, personal data of patients must be anonymised in order to ensure the patient’s privacy. In this thesis we compared a set of anonymization methods on the synthetically generated database. The database was composed of Slovenian patients, where sensitive personal information of each patient is their cholesterol level. We used the ARX software tool to perform anonymization methods. When comparing the methods, we measured the speed of the algorithm and the quality of anonymous data

The acetyl xylan esterase of Bacillus pumilus belongs to a family of esterases with broad substrate specificity

The Bacillus pumilus gene encoding acetyl xylan esterase tare) was identified and characterized. The axe gene was expressed and the recombinant enzyme produced in Escherichia coli was purified and characterized. The recombinant enzyme displayed similar properties to the acetyl xylan esterase (AXE) from B. pumilus. The AXE primary structure was 76% identical to the cephalosporin C deacetylase of B. subtilis, and 40% to two recently identified AXEs from Thermoanaerobacterium and Thermotoga maritima. These four proteins are of similar sire and represent a new family of esterases having a broad substrate specificity. The recombinant AXE was demonstrated to have activity on several acetylated substrates, including on cephalosporin C

Comparative study of anonymization methods on synthetically generated health database

By anonymizing data, we protect the identity of an individual from disclosing sensitive personal information. Hospitals store data on their patients in databases. Many of stored data is used for research purposes. According to the laws, personal data of patients must be anonymised in order to ensure the patient’s privacy. In this thesis we compared a set of anonymization methods on the synthetically generated database. The database was composed of Slovenian patients, where sensitive personal information of each patient is their cholesterol level. We used the ARX software tool to perform anonymization methods. When comparing the methods, we measured the speed of the algorithm and the quality of anonymous data

ANTI-INFECTIVE AND ANTI-TUMOR ACTIVITY OF SOME METAL COMPLEXES (MII-MIV) WITH SCHIFF BASES

Research and application of metal complexes of ruthenium, platinum, palladium and other d-block elements has been popular in recent time because the complexes of said metals with a wide range of organic ligands shown to be extremely efficient in the treatment of infectious and malignant diseases. In addition to platinum used long time as Cisplatin, Carboplatin and oxaplatin, new generation of anticancer complexes in their structure containe mainly Ru(II) and Ru(III). In the synthesis of anti-infective and anti-tumor drugs, emphasis is indicated on their cytotoxicity. Specifically, the aim is that the new anti-infective and anti-tumor agent does not damage healthy cells and affects only malignant cells or infectious agents. In this paper we make reference on some recent and significant researches in the field of inorganic synthesis of metal complexes with strong anti-tumor and anti-infective properties. Special emphasis is placed on the Schiff bases as organic ligands which are specially used in the synthesis of such agents

An in silico approach for structural and functional analysis of heavy metal associated (HMA) proteins in Brassica oleracea

Heavy metal ATPases (HMAs) are the most important proteins involved in heavy metal accumulation process. Brassica oleracea has 5 HMA (1-5) homologues whose 3D structure has been predicted and validated in this study by different bioinformatics tools. Phylogenetic and multiple sequence alignment analyses showed high relationship between HMA2 and HMA4, while two same domains were identified in all five HMA proteins: E1-E2 ATPase and haloacid dehydrogenase (HAD) domain. Four HMA (2-5) proteins were identified to be localized in the plasma membrane, while HMA1 localization is predicted to be in plastid. Interactome analysis revealed high interaction of all HMA (1-5) proteins with many metal ion binding proteins and chaperones. Among these, interesting and strong interaction is observed between all HMA (1-5) proteins and ATX1, while HMA1, HMA2 and HMA4 have been found to strongly interact with FP3 (farnesylated protein 3) and FP6 (farnesylated protein 6) proteins. Docking site predictions and electrostatic potentials between HMA2/HMA4 and the interactome proteins were explained and discussed in this study

DNA Binding Properties of Two Ruthenium(III) Complexes Containing Schiff Bases Derived from Salicylaldehyde: Spectroscopic and Electrochemical Evidence of CT DNA Intercalation

The interaction of CT DNA by two anionic Ru(III) complexes with N-substituted salicylidenimine ligands was investigated by spectroscopic titration and cyclic voltammetry. The result gives a surprising evidence for intercalation of DNA by the negatively charged complex species containing non typical intercalating ligands with Kb of order 104 M−1. Na[RuCl2(N-R-5-X-salim)2], where R represents butyl or phenyl and X = H, Cl, were characterized on the basis of elemental analysis, MALDI-TOF mass spectrometry, infrared, UV / visible spectroscopic measurements and cyclic voltammetry. (doi: 10.5562/cca2216