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Collagen hydrolysis, catalyzed by Zn(II)-dependent matrix metalloproteinases (MMPs), is a critical physiological process. Despite previous computational investigations into the catalytic mechanisms of MMP-mediated collagenolysis, a significant knowledge gap in understanding remains regarding the influence of conformational sampling and entropic contributions at physiological temperature on enzymatic collagenolysis. In our comprehensive multilevel computational study, employing quantum mechanics/molecular mechanics (QM/MM) metadynamics (MetD) simulations, we aimed to bridge this gap and provide valuable insights into the catalytic mechanism of MMP-1. Specifically, we compared the full enzyme–substrate complex in solution, clusters in solution, and gas-phase to elucidate insights into MMP-1-catalyzed collagenolysis. Our findings reveal significant differences in the catalytic mechanism when considering thermal effects and the dynamic evolution of the system, contrasting with conventional static potential energy surface QM/MM reaction path studies. Notably, we observed a significant stabilization of the critical tetrahedral intermediate, attributed to contributions from conformational flexibility and entropy. Moreover, we found that protonation of the scissile bond nitrogen occurs via proton transfer from a Zn(II)-coordinated hydroxide rather than from a solvent water molecule. Following C–N bond cleavage, the C-terminus remains coordinated to the catalytic Zn(II), while the N-terminus forms a hydrogen bond with a solvent water molecule. Subsequently, the release of the C-terminus is facilitated by the coordination of a water molecule. Our study underscores the pivotal role of protein conformational dynamics at physiological temperature in stabilizing the transition state of the rate-limiting step and key intermediates, compared to the corresponding reaction in solution. These fundamental insights into the mechanism of collagen degradation provide valuable guidance for the development of MMP-1-specific inhibitors.

Human matrix metalloproteinase-1 (MMP-1) is a zinc(II)-dependent enzyme that catalyzes collagenolysis. Despite the availability of extensive experimental data, the mechanism of MMP-1-catalyzed collagenolysis remains poorly understood due to the lack of experimental structure of a catalytically productive enzyme–substrate complex of MMP-1. In this study, we apply molecular dynamics and combined quantum mechanics/molecular mechanics to reveal the reaction mechanism of MMP-1 based on a computationally modeled structure of the catalytically competent complex of MMP-1 that contains a large triple-helical peptide substrate. Our proposed mechanism involves the participation of an auxiliary (second) water molecule (wat2) in addition to the zinc(II)-coordinated water (wat1). The reaction initiates through a proton transfer to Glu219, followed by a nucleophilic attack by a zinc(II)-coordinated hydroxide anion nucleophile at the carbonyl carbon of the scissile bond, leading to the formation of a tetrahedral intermediate (IM2). The process continues with a hydrogen-bond rearrangement to facilitate proton transfer from wat2to the amide nitrogen of the scissile bond and, finally, C–N bond cleavage. The calculations indicate that the rate-determining step is the water-mediated nucleophilic attack with an activation energy barrier of 22.3 kcal/mol. Furthermore, the calculations show that the hydrogen-bond rearrangement/proton-transfer step can proceed in a consecutive or concerted manner, depending on the conformation of the tetrahedral intermediate, with the consecutive mechanism being energetically preferable. Overall, the study reveals the crucial role of a second water molecule and the dynamics for effective MMP-1-catalyzed collagenolysis.

Co-existence of four Phytophthoraspecies in a small river in Bulgaria was established—P. plurivora, P. gonapodyides, P. chlamydosporaand P. gallica. The species identification was performed by DNA sequence analysis of the ITS region and the presence of a rare Phytophthoraspecies, P. gallica, which was isolated for the first time in Bulgaria, was recognized. Additional sequencing of the mitochondrial cox1gene and two other nuclear genes (tef1and Btub)confirmed the species identification of the four isolates. P. gallicabelongs to clade 10 and was characterized using classical morphological and physiological methods. Pathogenicity testing of collected Phytophthoraisolates on detached leaves and cuttings of poplar (Populus nigra), black locust (Robinia pseudoacacia), hawthorn (Crataegus monogyna) and blackberry (Rubus fruticosus) was conducted. All Phytophthoraisolates were able to cause leaf necrosis on each of tested plant species with varying intensity, except for P. gallicathat did not infect only poplar leaves, but induced disease symptoms on the other three plant species. Additional experiments with cuttings of the analyzed plants confirmed the ability of P. gonapodyides, P. chlamydosporaand P. plurivorato infect poplar, black locust and hawthorn. All isolated Phytophthoraspecies were determined as a potential threat for the riparian ecosystems in the region based on the result of pathogenicity analyses.

Fe(II)-dependent oxygenases employ hydrogen atom transfer (HAT) to produce a myriad of products. Understanding how such enzymes use dynamic processes beyond the immediate vicinity of the active site to control the selectivity and efficiency of HAT is important for metalloenzyme engineering; however, obtaining such knowledge by experiments is challenging. This study develops a computational framework for identifying second coordination sphere (SCS) and especially long-range (LR) residues relevant for catalysis through dynamic cross-correlation analysis (DCCA) using the human histone demethylase PHF8 (KDM7B) as a model oxygenase. Furthermore, the study explores the mechanistic pathways of influence of the SCS and LR residues on the HAT reaction. To demonstrate the plausibility of the approach, we investigated the effect of a PHF8 F279S clinical mutation associated with X-linked intellectual disability, which has been experimentally shown to ablate PHF8-catalyzed demethylation. In agreement, the molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) studies showed a change in the H31–14K9me2 substrate orientation and an increased HAT barrier. We systematically analyzed the pathways by which the identified SCS and LR residues may influence HAT by exploring changes in H3K9me2 substrate orientation, interdomain correlated motions, HAT transition state stabilization, reaction energetics, electron transfer mechanism, and alterations in the intrinsic electric field of PHF8. Importantly, SCS and LR variations decrease key motions of α9−α12 of the JmjC domain toward the Fe(IV)-center that are associated with tighter binding of the H31–14K9me2 substrate. SCS and LR residues alter the intrinsic electric field of the enzyme along the reaction coordinate and change the individual energetic contributions of residues toward TS stabilization. The overall results suggest that DCCA can indeed identify non-active-site residues relevant for catalysis. The substitutions of such dynamically correlated residues might be used as a tool to tune HAT in non-heme Fe(II)- and 2OG-dependent enzymes.

The growth response of three phytopathogens to inhibitory activity of essential oils (EOs), derived from three monarda (Monarda didymaL.) genotypes, was evaluated. The antimicrobial effect was assayed by agar diffusion method. The pathogens expressed distinct growth response to the oils. As compared to colony growth of non-treated controls, all EOs remarkably suppressed Phytophthora plurivora; EO1 inhibited Diaporthe nobilisto 31.5% and Alternaria alternatato 35.5% of the controls; EO2 restricted the growth of the latter two species to 41.3% and 50.5% from the control, respectively. The weakest inhibitory effect was established for EO3 which stopped the development of A. alternatato 67.2% and of D. nobilisto 59.1% of their controls. GC–MS analyses of the oils identified altogether 46 chemical compounds. The largest group of constituents was the group of oxygenated monoterpenes (61.6–66.0%), followed by monoterpene hydrocarbons (16.6–17.7%), non-terpenes (12.6–15.5%) and sesquiterpene hydrocarbons (2.3–3.5%). Considering the most abundant compound, EO1 and EO3 were determined of thymol and EO2 of carvacrol chemotypes. P. plurivorawas equally strongly susceptible to the EOs of both chemotypes, whereas the behavior of the other two species suggested different susceptibility to the prevailing EO constituents. The total antioxidant activity was very high but differed between the oils. The obtained results add novel information on the inhibitory activity of EOs from various M. didymagenotypes and indicate specificity of the growth response of the studied microorganisms to the chemical ingredients in the applied plant products.

ABSTRACTDuring an investigation of rivers in Bulgaria, an isolate of Phytophthora(RLKam2016/61c) was recovered and initially identified as Phytophthora sansomeanabased on internal transcribed spacer region (ITS) sequence data. However, the sequencing of the mitochondrial cytochrome coxidase subunit I (cox1) gene revealed high similarity to Phytophthorasp. kelmania, and sequencing of other nuclear regions (β-tubulin [Btub] and translation elongation factor 1-alpha [tef1]) revealed a significant number of polymorphisms, indicating a possible hybridization event. Additional cloning and sequencing of the nuclear ITS and Btubregions showed the presence of two distinct groups of alleles, one of which was highly similar to P. sansomeana, whereas the other was similar to a species complex that includes Phytophthorasp. kelmania. Therefore, the new hybrid was named Phytophthora× sansomeana. It is characterized by fast growth on V8 juice agar (V8A) and carrot agar (CA), moderate aerial mycelium with radiate pattern of the colonies and relatively slower growth rate on malt extract agar (MEA) and potato dextrose agar (PDA), and petaloid to rosaceous pattern of the colonies with fluffy aerial mycelium. The optimum growth temperature for P. × sansomeanawas at 25 C, with an average growth rate of 9 mm per day. Abundant sporangium formation of the isolate in spring water was observed, but the hybrid was sterile in culture. Pathogenicity analyses of the hybrid were conducted in comparison with the most closely related subclade 8a species from our collection, P. pseudocryptogea. The inhibition effect on the root growth of young seedlings of two legumes, common pea and vetch, as well as on cuttings of the ornamental plant coleus induced by both phytopathogens was significant. No effect of either the new hybrid or P. pseudocryptogeaon the growth of maize seedlings was observed.

Pathogenicity of seven Phytophthoraspecies (P. plurivora, P. citricola, P. lacustris, P. gonapodyides, P. chlamydospora, P. pseudocryptogeaand P. hydropathica) to ornamental plant Plectranthus scutellarioideswas evaluated. Susceptibility of the tested plant to the selected pathogens was analyzed by a baiting technique with detached leaves and an infection of cuttings. P. pseudocryptogeawas determined as the most aggressive pathogen to the coleus plant according to the results of both methods. P. lacustris, P. gonapodyides, P. chlamydosporaand P. hydropathicainduced comparable disease symptoms on tested leaves as well as cuttings. P. plurivoraand P. citricolademonstrated less aggressiveness to leaves of P. scutellarioides, but strongly inhibited the growth of the roots of the cuttings. All tested Phytophthoraspecies were recognized as a real threat for coleus plants in their natural habitat, but they could also compromise its cultivation in greenhouses, nurseries and parks. In addition, the ability of the fungicide azoxystrobin for an effective control of Phytophthoraspecies was proved.

AlkB and its human homologue AlkBH2 are Fe(II)- and 2-oxoglutarate (2OG)-dependent oxygenases that repair alkylated DNA bases occurring as a consequence of reactions with mutagenic agents. We used molecular dynamics (MD) and combined quantum mechanics/molecular mechanics (QM/MM) methods to investigate how structural dynamics influences the selectivity and mechanisms of the AlkB- and AlkBH2-catalyzed demethylation of 3-methylcytosine (m3C) in single (ssDNA) and double (dsDNA) stranded DNA. Dynamics studies reveal the importance of the flexibility in both the protein and DNA components in determining the preferences of AlkB for ssDNA and of AlkBH2 for dsDNA. Correlated motions, including of a hydrophobic β-hairpin, are involved in substrate binding in AlkBH2–dsDNA. The calculations reveal that 2OG rearrangement prior to binding of dioxygen to the active site Fe is preferred over a ferryl rearrangement to form a catalytically productive Fe(IV)═O intermediate. Hydrogen atom transfer proceeds via a σ-channel in AlkBH2–dsDNA and AlkB–dsDNA; in AlkB–ssDNA, there is a competition between σ- and π-channels, implying that the nature of the complexed DNA has potential to alter molecular orbital interactions during the substrate oxidation. Our results reveal the importance of the overall protein–DNA complex in determining selectivity and how the nature of the substrate impacts the mechanism.

Organosulfur silanes grafted on an aluminum current collector have been proposed and demonstrated to function as a sulfur source in the cathode for a lithium–sulfur (Li–S) battery. Bis[3-(triethoxysilyl)propyl]disulfide silane (TESPD) and bis[3-(triethoxysilyl)propyl]tetrasulfide silane (TESPT) are typical examples of organosulfur complexes used for the study. These organosulfur silanes act as an insulator. Formation of polysulfides (Li2Sx), which is a major bottleneck in the case of elemental sulfur, can be eliminated using this novel cathode. In the absence of charge-carrying polysulfide species, the role of insulating TESPD/TESPT in the charge conduction pathway is an open question. Insight into the interface between the Al current collector and grafted TESPD/TESPT at an atomic level is a prerequisite for addressing the charge conduction pathway. The systematic theoretical methodology is developed based on electronic structure calculations and ab initio molecular dynamics simulations to propose the realistic cathode model (hydration environment) for the Li–S battery. A cluster model is developed to predict the reduction potentials of TESPD/TESPT disclosing the reduction reaction with Li, resulting in the intramolecular S–S bond breaking which is validated by experimental cyclic voltammetry measurements. A realistic cathode model between the aluminum current collector and TESPD/TESPT is also proposed to mimic the experimental conditions where the Al surface was exposed to O2and H2O. The top few layers of Al are transformed into α-Al2O3and covered with H2O molecules in the vicinity of grafted TESPD/TESPT. The structural models are further validated by comparing simulated S 2p binding energies with experimental X-ray photoelectron spectroscopy studies.

Nature uses 64 codons to encode the synthesis of proteins from the genome, and chooses 1 sense codon—out of up to 6 synonyms—to encode each amino acid. Synonymous codon choice has diverse and important roles, and many synonymous substitutions are detrimental. Here we demonstrate that the number of codons used to encode the canonical amino acids can be reduced, through the genome-wide substitution of target codons by defined synonyms. We create a variant of Escherichia coliwith a four-megabase synthetic genome through a high-fidelity convergent total synthesis. Our synthetic genome implements a defined recoding and refactoring scheme—with simple corrections at just seven positions—to replace every known occurrence of two sense codons and a stop codon in the genome. Thus, we recode 18,214 codons to create an organism with a 61-codon genome; this organism uses 59 codons to encode the 20 amino acids, and enables the deletion of a previously essential transfer RNA.

AbstractBulgaria, like many other countries, has experienced the far-reaching consequences of the Coronavirus disease 2019 (COVID-19) pandemic. Seroprevalence studies serve as a crucial method for assessing the exposure and immunity levels within a population. In this serosurvey, which is the first of this kind conducted in Bulgaria, we enrolled 104 healthcare workers (HCWs) from one front-line Bulgarian hospital and 237 individuals from the general population. Serum samples were collected in December 2021 from the general population and in February 2023 from HCWs and the general population. The presence of four anti-SARS-CoV-2 antibodies was evaluated: anti-Spike 1-IgG, anti-Nucleoprotein-IgG, anti-Spike1-IgA and anti-Recombinant binding domain neutralizing antibodies. Our results showed high percentages of seropositivity in both the HCWs and the general population (99% and 78%, respectively) in February 2023. HCWs had significantly higher mean IgA and mean anti-S1-IgG antibody levels compared to the general population. The seropositivity in the general population in December 2021 was 79%. The mean levels of IgA and anti-NCP-IgG were significantly higher, whereas the mean anti-S1-IgG levels were significantly lower in February 2023 compared to December 2021. We found a strong correlation between neutralizing antibodies and anti-S1-IgA and anti-S1-IgG antibodies for all tested groups. It is necessary to perform large-scale serosurveys to provide analysis of the seroprevalence in a larger population and its dynamics over time and to facilitate evidence-based strategies that will safeguard the health and well-being of the Bulgarian population and contribute to the global efforts in combating the COVID-19 pandemic.

AbstractIn this study, we investigated the potential association between the severity of COVID-19 (coronavirus disease 2019) and nasopharyngeal viral loads or serum antibody levels and evaluate the temporal dynamics of antibodies against SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Using ELISA (enzyme-linked immunosorbent assay), we determined the presence of IgA, IgM and IgG antibodies in 450 serum samples from 122 patients for a period of 9 months after disease onset. Viral burden was quantified by RT-PCR (reverse transcription polymerase chain reaction) in 270 nasopharyngeal swab samples from 122 patients for a period of 4 weeks after the onset of the symptoms. Higher antibody values were generally seen in patients with moderate and severe disease compared to patients with mild COVID-19. Significant differences were established in IgA and IgG antibody levels at weeks 3–4 and 5–13 after the disease onset. In all severity groups, seroconversion rates were high and a similar pattern was observed with IgM antibodies quickly decreasing after reaching peak levels and IgA and IgG antibodies persisting at high values up to 9 months. The mean viral loads were higher in the mild group during the first 2 weeks and in the moderate and severe groups later on. However, the differences were not statistically significant. The IgA and IgG antibody response was significantly stronger in patients with moderate/severe disease around the time of peak antibody production as well as in vaccinated patients. No definitive association between viral load levels and the severity of COVID-19 was observed.

AbstractNew bacterial strain BN66 was isolated by selective enrichment, identified as Bacillus cereusand proved to degrade crude oil, together with biosurfactant synthesis. Free and cryogel immobilized Bacillus cereuscells were involved in a crude oil degradation process. The studied strain degraded 93% of the aliphatic fraction for 48 h. We immobilized cells in two types of cryogels synthesized from high molar mass polyacrylamide or acrylamide precursors and explored the degradation capability and possibility for re-use of the preparations. Reusability tests revealed that the oil degradation ability of immobilized cells was stable after 47 days (28 °C and shaker speed 120 rpm) and the degradation rate of immobilized cells was maintained at a high level up to the 20thcycle of operation. The matrices obtained from high molar mass polyacrylamide appeared to be more suitable due to their ability to keep the cells within the carrier. The cells immobilized in cryogels exhibited more effective degradation for 22 active cycles at semicontinuous mode of operation compared to only three cycles performed by free cells.

In this study sol-gel hybrid materials in the system SiO2-chitosan (CS) - polyethylene glycol (PEG), as novel structures with potential application in bioremediation were investigated. The organic components - CS and PEG were used as structural modifiers for functionality improvement. The catabolic activity to n-hexadecane of Pseudomonas aeruginosaBN10 free and immobilized cells was estimated. The cell immobilization technique was employed to evaluate its efficiency on biodegradation and protective effect from high levels of hydrocarbons. The characteristics of obtained hybrid materials were investigated via X-ray Diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Atomic-force microscopy(AFM) analyses. The obtained results revealed that the organic part in the synthesized hybrids is important for microstructure and defined properties creation. The rate of n-hexadecane mineralization by the bacterial strain was influenced by variation in cell densities applied in the immobilization procedures. Semi-continuous processes with multiple xenobiotic supplies were carried out. The synthesized by the sol-gel method hybrid matrices proved to be suitable carriers for realizing an effective biodegradation process of n-hexadecane by Pseudomonas aeruginosaBN10. Biodegradation of 50 kg/m3of n-hexadecane was realized by free cells. Significantly greater quantity (150 kg/m3) was mineralized for 15 active cycles by entrapped bacterial cells. Biodegradation process with gradual increase of xenobiotic concentration reaching 30 kg/m3for 120 h was also accomplished.

The fat-mass and obesity-associated protein (FTO) is an Fe(II)- and 2-oxoglutarate (2OG)-dependent oxygenase of the AlkB family and is linked with obesity and cancer. The enzyme is identified as a single-stranded (ss)DNA/RNA demethylase with N6-methyladenine (m6A) modification in RNA as its most favorable substrate. Here we used molecular dynamics (MD), metadynamics (MetD), and hybrid quantum mechanics/molecular mechanics (QM/MM) calculations to reveal the catalytic mechanism of FTO with pentanucleotide-ssRNA(m6A) substrate and elucidate the effects of clinically significant mutations R316Q and S319F. The calculations explored the catalytic mechanism of the O2activation and substrate oxidation in the wild-type (WT) FTO, revealing that different networks of residues stabilize the transition states of the different reaction steps. The mutations influence the interactions in the jelly-roll motif and loops in FTO, and, in particular, S319F strongly affects the substrate binding. The R316Q mutant slows down the O2activation and hydrogen atom transfer (HAT) rates, in agreement with experimental studies.

Total hip joint replacement considered one of the success sections of the modern medicine, but still the wear of total hip prostheses is a significant clinical problem and this problem might be increasingly complex with adding the influence of pelvis width and leg length during the preclinical testing. This study aims to analyze the effect of the leg length (femur and tibia) and the pelvis width on the wear behavior of ultra-high molecular weight polyethylene (UHMWPE) hip cup. The experiments have been carried out on a total leg joint’s simulator (TLJS), which was particularly designed for this purpose according to ISO 14242-1 standard. The TLJS consists of three units: leg components (femur, tibia, and foot), quick-return mechanism, and cam mechanism were used to reproduce the flexion–extension and external–internal movement, respectively, and upper body was used to stimulate the pelvis construction and applied load. The wear behavior of the tested cups (in weight loss form) was evaluated under dry lubricating conditions, and then the wear mechanism of worm cups was examined by using scanning electron microscopy. The results showed that the length of the femur, tibia, and pelvis width have a positive effect on the wear rate of the tested cups due to flexion and pelvic moment which is resulted by the ground reaction force and pelvic rotation force.

Objectives Cytokine dysregulation has been proposed as one of the main culprits for severe COVID-19 and poor prognosis. We examined the parallel presence of lymphopoietic, proinflammatory, Th1, Th2, regulatory cytokines, and chemokines in the serum of 47 patients with mild, moderate, and severe COVID-19 and evaluated the association between cytokine concentrations and disease severity.Methods A multiplex quantitative cytokine analysis ProcartaPlex™ immunoassay was applied, using the LuminexTM200X detection system (Invitrogen).Results The concentrations of twelve cytokines: IL-18, IFN-gamma, TNF-alpha; IL-21; IL-1alpha, IL-1beta, IL-6, IL-22; IL-10, IL-1RA; IL-7 and IFN-alpha were consistently elevated in the studied serum samples. All examined chemokines—Eotaxin, GRO-alpha, IL-8, IP-10, MCP-1, MIP-1alpha, MIP-1beta, SDF-1alpha, and RANTES, were detectable in all studied groups, confirming their importance in mediating the adaptive immune response regardless of disease severity. The serum concentrations of six mediators: IL-1beta, IL-6, IL-18, IL-10, IL-8, and IP-10, showed statistically significant differences among the groups with different disease severity. IL-6, IL-1beta, and IL-10 were more significantly elevated in severe cases while milder symptoms were associated with lower levels of IL-8 and IP-10.Conclusion Overall, the studied chemokines demonstrated an associated production in acute COVID-19 infection. A strong correlation was observed between the Th1 mediators IL-18 and IL-10 and the proinflammatory IL-6 in the severe COVID-19 group. Our results indicated that severe COVID-19 was characterized by a dysregulated cytokine pattern whereby the Th1 immune response is outweighed by the immunoregulatory response, while inhibitory signals cannot balance the hyperinflammatory response.

Backround: Ginkgo biloba extract (GBE) is one of the most widely used extracts in food supplements and herbal medicines with wide spectrum of activities. Introduction: Extracts of Ginkgo leaves contain biologically active flavonoid glycosides from different types mainly flavonol derivatives such as rutin. The amounts of flavone glycosides, one of the key active components in GBE, vary in accordance with the source of the Ginkgo leaves and the extraction and other used procedures. Method: With respect to quality control optimization solutions, a simple, precise, accurate and reproducible HPLC method for assay of flavonol glucoside rutin is developed and applied to supplements containing GBE. The method is based on the use of isocratic mobile phase regimen with UV detection. Result: Rutin is successfully separated using 4.6 x 150 mm column RP-18, ODS with particle size 5 μm without preliminary hydrolysis. The proposed method is validated in accordance with ICH and European Pharmacopoeia 8.0 requirements and compared with HPLC methods in European Pharmacopoeia and US Pharmacopoeia. Conclusion: The proposed method could be applicable for identification, purity and assay tests of supplements containing Ginkgo biloba extract according to Pharmacopoeia requirements.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne human viral disease with fatality rate up to 30%. Two genetic lineages of CCHF virus (CCHFV) are present in Europe – lineage Europe 1 which contains pathogenic CCHFV strains, and lineage Europe 2 consisting of AP92 and AP92-like strains. In order to investigate CCHFV distribution and potential risk for humans, ticks were collected from livestock in the five districts where CCHF cases have been reported in the last five years in Bulgaria. CCHFV lineage Europe 1 was detected in 39 of 623 Hyalomma marginatumticks (6.3%; range per village 2.7–15.2%), while CCHFV lineage Europe 2 was detected for the first time in Bulgaria in 49 of 415 Rhipicephalus sanguineussensu lato ticks (11.8%; range 0–58.3%). The present study shows that both Europe 1 and Europe 2 CCHFV lineages are present in Bulgaria. The pathogenic role of the AP92-like strains remains to be elucidated.

The capability of the biosurfactant-producing strain Rhodococcus wratislawiensisBN38 to mineralize both aromatic and aliphatic xeno- biotics was proved. During semicontinuous cultivation 11 g/l phenol was completely degraded within 22 cycles by Rhodococcusfree cells. Immobilization in a cryogel matrix was performed for the first time to enhance the biodegradation at multiple use. A stable simultaneous hydrocarbon biodegradation was achieved until the total depletion of 20 g/l phenol and 20 g/l n-hexadecane (40 cycles). The alkanotrophic strain R. wratislawiensisBN38 preferably degraded hexadecane rather than phenol. SEM revealed well preserved cells entrapped in the heterogeneous super-macroporous structure of the cryogel which allowed unhindered mass transfer of xenobiotics. The immobilized strain can be used in real conditions for the treatment of contaminated industrial waste water.

The capability of the biosurfactant-producing strain Rhodococcus wratislawiensisBN38 to mineralize both aromatic and aliphatic xeno- biotics was proved. During semicontinuous cultivation 11 g/l phenol was completely degraded within 22 cycles by Rhodococcusfree cells. Immobilization in a cryogel matrix was performed for the first time to enhance the biodegradation at multiple use. A stable simultaneous hydrocarbon biodegradation was achieved until the total depletion of 20 g/l phenol and 20 g/l n-hexadecane (40 cycles). The alkanotrophic strain R. wratislawiensisBN38 preferably degraded hexadecane rather than phenol. SEM revealed well preserved cells entrapped in the heterogeneous super-macroporous structure of the cryogel which allowed unhindered mass transfer of xenobiotics. The immobilized strain can be used in real conditions for the treatment of contaminated industrial waste water.

Every day, academic world is confronted with new challenges and possible scams and awareness of them is necessary for researchers. Lack of information about these issues would lead to serious problems including the difficulties at finding validated academic resource. Journals are the most important academic resource for a researcher however certain unethical practices have come to light regarding authenticity of certain Journals. Journals with names that are similar to existing (and reputed) journals is one of the recently noted problem. These names occasionally are used by 'certain dubious publishers' to deceive researchers. In this short paper we address this issue of similar names in academic literature and the way it is used to deceive researchers.