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Development of biomaterials for hernia and pelvic organ prolapse (POP) repair is encouraged because of high local complication rates with current materials. Therefore, we aimed to develop a functionalized electrospun mesh that promotes tissue ingrowth and provides adequate mechanical strength and compliance during degradation. We describe the in vivo function of a new supramolecular bioactivated polycarbonate (PC) material based on fourfold hydrogen bonding ureidopyrimidinone (UPy) units (UPy-PC). The UPy-PC material was functionalized with UPy-modified cyclic arginine-glycine-aspartic acid (cRGD) peptide additives. Morphometric analysis of the musculofascial content during wound healing showed that cRGD functionalization promotes myogenesis with inhibition of collagen deposition at 14 days. It also prevents muscle atrophy at 90 days and exerts an immunomodulatory effect on infiltrating macrophages at 14 days and foreign body giant cell formation at 14 and 90 days. Additionally, the bioactivated material promotes neovascularization and connective tissue ingrowth. Supramolecular cRGD-bioactivation of UPy-PC-meshes promotes integration of the implant, accelerates tissue ingrowth and reduces scar formation, resulting in physiological neotissue formation when used for abdominal wall reconstruction in the rat hernia model. Moreover, cRGD-bioactivation prevents muscle atrophy and modulates the inflammatory response. Our results provide a promising outlook towards a new type of biomaterial for the treatment of hernia and POP. Statement of Significance: Development of biomaterials for hernia and pelvic organ prolapse (POP) repair is encouraged because of high local complication rates with current materials. Ureidopyrimidinone-polycarbonate is a elastomeric and biodegradable electrospun mesh, which could mimic physiological compliance. The UPy-PC material was functionalized with UPy-modified cyclic arginine-glycine-aspartic acid (cRGD) peptide additives. Supramolecular cRGD-bioactivation of UPy-PC-meshes promotes integration of the implant, accelerates tissue ingrowth and reduces scar formation, resulting in physiological neotissue formation when used for abdominal wall reconstruction in rat hernia model. Moreover, cRGD-bioactivation prevents muscle atrophy and modulates the inflammatory response. These data provide a promising outlook towards a new type of biomaterial for the treatment of hernia and POP.

A hybrid material incorporating gold nanoparticles (Au-NPs) in polydimethylsiloxane (PDMS) has been synthesized. Gold nanoparticles gained wide interest for their optical, chemical and physical properties, such as surface plasmon oscillations resonant absorption, chemical structure, imaging and sensing. Au-NPs can be conjugated with several functionalizing agents, such as polymeric chains, improving their properties and performances. PDMS composites with weight percentages ranging between 0.1 and 0.2% of spherical Au-NPs (10 nm diameter), were produced. In this work, we report on different dispersion effects of gold nanoparticles in PDMS. The surface morphology was investigated by atomic force microscopy (AFM) and wetting ability analyses. The presence of structures inside both virgin and hybrid PDMS containing Au-NPs was preliminary investigated by Small Angle X-ray Scattering (SAXS). The optical performance of such hybrid material was studied by UV-VIS spectroscopy, in transmission mode. An enhancement of the absorption was reported as a function of increasing percentage of gold nanoparticles and changing the nanoparticles dispersion approach. The presented hybrid material could be promising for many useful applications, such as optical waveguides, sensors and switches in optoelectronics.

Background/Aims: The ewe is increasingly being used as an animal model for pelvic floor disorders. The aim was to further characterize changes in the vaginal properties during its entire lifespan. Methods: Vaginal tissues were collected at different stages of reproductive life (neonatal, prepubescence, nulliparous, primiparous, multiparous, and menopausal; ≥6 ewes/group). Vaginal size, as well as active and passive biomechanics, was measured. Microscopy included thickness of glycogen, epithelium, lamina propria and muscularis thickness, densities of collagen, elastin, smooth muscle, and nerves. Results: Vaginal dimensions increase during adolescence, peak at reproductive levels, and decrease sharply after ovariectomy. One year after first delivery, the distal vagina gets more compliant, yet this is reversed later in life. The thickness of glycogen staining epithelial layers changed with puberty and menopause. The epithelium was markedly thicker after multiple deliveries. The thickness of lamina propria and muscularis increased in puberty and in nulliparous. Semi-quantitative collagen assessment demonstrated a lower collagen and higher elastin content after first and multiple deliveries. Conclusion: The changes in the ovine vaginal wall during representative moments of her lifespan parallel those observed in women.

Objective In sheep of reproductive age, we aimed to document decrease in epithelial thickness, glycogen amount, and other vaginal changes after castration and the effect of Er:YAG laser as used clinically. Methods On day 0, 16 sheep underwent ovariectomy. They were randomized to sham or three vaginal Er:YAG laser applications at monthly intervals. Primary outcome was vaginal epithelial thickness (d60, d71, d73, d77, and d160). Secondary outcomes included indicators of atrophy (vaginal health index = VHI), pH, cytology, morphology at the above time points, microcirculation focal depth (FD; d70 and d160), and at sacrifice (d160) vaginal dimensions and active and passive biomechanical testing. Results Menopausal changes between 60 and 160 days after ovariectomy included a progressive decrease in epithelial thickness, in VHI, FD, glycogen, elastin content and vasculature, and an increase in pH and collagen content. In lasered animals, the first day a few white macroscopic foci were visible and an increase in pH was measured. Both disappeared within 3 days. Seven days after laser the epithelial thickness increased. At sacrifice (d160), there were no differences between sham and laser group in vaginal dimensions, morphometry, mitotic and apoptotic activity, active contractility, vaginal compliance, except for a lower blood vessel density in the lamina propria of the midvagina in the laser group. Conclusions In reproductive sheep, ovariectomy induces vaginal atrophy evidenced in different outcome measurements. Vaginal Er:YAG laser induced visual impact, a short-term increase in epithelial thickness yet no long-term changes compared to sham therapy in menopausal controls.

A common shortcoming of current tissue engineered constructs is the lack of a functional vasculature, limiting their size and functionality. Prevascularization is a possible strategy to introduce vascular networks in these constructs. It includes among others co-culturing target cells with endothelial (precursor) cells that are able to form endothelial networks through vasculogenesis. In this paper, we compared two different prevascularization approaches of bio-artificial skeletal muscle tissue (BAM) in vitro and in vivo. In a one-stage approach, human muscle cells were directly co-cultured with endothelial cells in 3D. In a two-stage approach, a one week old BAM containing differentiated myotubes was coated with a fibrin hydrogel containing endothelial cells. The obtained endothelial networks were longer and better interconnected with the two-stage approach. We evaluated whether prevascularization had a beneficial effect on in vivo perfusion of the BAM and improved myotube survival by implantation on the fascia of the latissimus dorsi muscle of NOD/SCID mice for 5 or 14 d. Also in vivo, the two-stage approach displayed the highest vascular density. At day 14, anastomosis of implanted endothelial networks with the host vasculature was apparent. BAMs without endothelial networks contained longer and thicker myotubes in vitro, but their morphology degraded in vivo. In contrast, maintenance of myotube morphology was well supported in the two-stage prevascularized BAMs. To conclude, a two-stage prevascularization approach for muscle engineering improved the vascular density in the construct and supported myotube maintenance in vivo.

Variants of L1210 leukemia cells-namely, parental P-glycoprotein-negative S cells and R and T cells expressing P-glycoprotein, due to selection with vincristine and transfection with the human p-glycoprotein gene, respectively-were used. The responses of these cell variants to two naturally occurring isothiocyanates-sulforaphane (SFN, from cruciferous vegetables) and allyl isothiocyanate (AITC, from mustard, radish, horseradish and wasabi)-were studied. We obtained conflicting results for the cell death effects induced by isothiocyanates, as measured by i. cell counting, which showed inhibited proliferation, and ii. cell metabolic activity via an MTS assay, which showed an increased MTS signal. These results indicated the hyperactivation of cell metabolism induced by treatment with isothiocyanates. In more detailed study, we found that, depending on the cell variants and the isothiocyanate used in treatment, apoptosis and necrosis (detected by annexin-V cells and propidium iodide staining), as well as autophagy (detected with monodansylcadaverine), were involved in cell death. We also determined the cell levels/expression of Bcl-2 and Bax as representative anti- and pro-apoptotic proteins of the Bcl-2 family, the cell levels/expression of members of the canonical and noncanonical NF-&kappa, B pathways, and the cell levels of 16 and 18 kDa fragments of LC3B protein as markers of autophagy.

Glasses doped with Er and Yb show strong luminescence around 1530 nm, which makes them attractive luminophores for the preparation of multifunctional optical components. This article is focused on the influence of ZnO on the optical and luminescence properties of Er-Yb zinc-silicate glasses. The influence of silver doping on the resulting luminescence properties of the prepared glasses has also been investigated. Three types of silicate glasses containing different amounts of ZnO and RE ions (Er and Yb) were prepared. For all the glasses prepared, their density, glass-transformation temperature and refractive index were determined. Moreover, these glasses were doped with silver using two methods - ion implantation and ion exchange. The presence of silver metal nanoparticles was observed using optical absorption in the UV-VIS range. Photoluminescence spectroscopy was used to observe the effect of the presence silver or zinc oxide on the intensity of luminescence. The results have shown that the enhancement of ZnO content positively influenced erbium luminescence at 1530 nm without affecting the transparency or homogeneity of the glass matrix. Moreover, the presence Ag+ ions in this special type of glass matrix positively contributed to the enhancement of erbium photoluminescence.

Contributions of voltage sensing S4 segments in domains I – IV of CaV3.1 channel to channel activation were analyzed. Neutralization of the uppermost charge in individual S4 segments by exchange of arginine for cysteine was employed. Mutant channels with single exchange in domains I – IV, in two adjacent domains, and in all four domains were constructed and expressed in HEK 293 cells. Changes in maximal gating charge Qmax and the relation between Qmax and maximal conductance Gmax were evaluated. Qmax was the most affected by single mutation in domain I and by double mutations in domains I + II and I + IV. The ratio Gmax/Qmax proportional to opening probability of the channel was significantly decreased by the mutation in domain III and increased by mutations in domains I and II. In channels containing double mutations Gmax/Qmax ratio increased significantly when the mutation in domain I was included. Mutations in domains II and III zeroed each other. Mutation in domain IV prevented the decrease ca...

Purpose Cardiomyocytes progenitor cells (CMPCs) are a candidate cell source for cardiac regenerative therapy. To assess their full potential for cardiac regeneration, it is essential to know if and how CMPCs sense and respond to the three-dimensional (3D) environment and the mechanical stimuli provided by the beating heart. Therefore, we study the response to cyclic strain of undifferentiated and predifferentiated human CMPCs in a 2D environment, as well as CMPC responses to unidirectionally constrained versus stress-free (unconstrained) 3D environments. The latter responses were studied using a hydrogel system that allows for interaction of the cells with a simulated ‘host’ tissue. Methods To test mechanosensitivity of CMPCs in 2D and 3D environments, the response of L9TB CMPCs to uniaxial (cyclic) strain (10% with 0.5 Hz) was investigated. To represent the 3D environment, CMPCs were cultured in unidirectionally constrained and stress-free collagen/Matrigel hydrogels, where the constrainment provides a static strain to the cells. The cellular mechanoresponse to the applied (cyclic) strain was quantified by cellular re-orientation away from the strain direction (strain avoidance). Next to cellular re-orientation, the effect of strain on cell differentiation was analyzed. Results Our results indicate that while undifferentiated cells maintain their original orientation, upon early cardiomyogenic differentiation (predifferentiated) CMPCs exhibit a distinct strain avoidance response during 48hrs of cyclic straining in a 2D environment. In 3D unidirectionally constrained hydrogels, undifferentiated CMPCs retain their cardiomyogenic profile. CMPCs cultured in 3D collagen/Matrigel hydrogels respond to static mechanical strains as expected by cell alignment. Conclusions Our results suggest that CMPCs respond to the presence of mechanical stimuli, in this research mimicked by the application of uniaxial (cyclic) strain in 2D and 3D environments, suggesting that CMPCs are indeed mechanosensitive. Although in 2D environments, mechanosensitivity of the CMPCs is dependent on their differentiation status. Our findings provide the first understanding of the ability of human CMPCs to sense mechanical stimuli, which is the first initial step in mechanotransduction. Mechanotransduction is essential for optimal recruitment, migration, and mechanical integration of progenitor cells into the injured myocardium. Therefore, the presented results can contribute to enhance efficacy of current treatments of cardiac disease, as well as to develop novel endogenous regeneration strategies.

Treatment of infections caused by pathogenic bacteria is still harder. Due to increasing number of microbial species resistant against so far invented antibiotics. This presents great problem for public health. One of the potential solutions seems to be antimicrobial peptides. Those peptides are synthetized in all organisms as a part of innate immunity with rapid mode of antimicrobial action. Lot of them have been isolated from bacteria, plants, insects and mammals as well. Our project was aimed on finding such peptides in plant extracts, respectively in leaves of Brassica napus (canola), Solanum lycopersicum (tomato) and Tetragonia tetragonioides (New Zealand spinach). We used several separation techniques to obtain fractions containing compounds of peptide nature with hydrophobic character. Antimicrobial activity of these fractions was tested against several gram-positive and gram-negative bacteria. Mass spectrometry analysis of antimicrobial active fractions proved presence of low molecular peptides with molecular masses 1.9 - 4.9 kDa and a partial amino acid sequence in hydrophobic part of Tetragonia extract. In hydrophilic fraction of the Solanum extract with proved antibacterial activity two patogenesis-related proteins with antifungal activity NP24 and TPM-1 were detected.

The aim of the study was to investigate how selected natural compounds (naringin, caffeic acid, and limonene) induce shifts in both bacterial community structure and degradative activity in long-term polychlorinated biphenyl (PCB)-contaminated soil and how these changes correlate with changes in chlorobiphenyl degradation capacity. In order to address this issue, we have integrated analytical methods of determining PCB degradation with pyrosequencing of 16S rRNA gene tag-encoded amplicons and DNA-stable isotope probing (SIP). Our model system was set in laboratory microcosms with PCB-contaminated soil, which was enriched for 8 weeks with the suspensions of flavonoid naringin, terpene limonene, and phenolic caffeic acid. Our results show that application of selected plant secondary metabolites resulted in bacterial community structure far different from the control one (no natural compound amendment). The community in soil treated with caffeic acid is almost solely represented by Proteobacteria, Acidobacteria, and Verrucomicrobia (together over 99 %). Treatment with naringin resulted in an enrichment of Firmicutes to the exclusion of Acidobacteria and Verrucomicrobia. SIP was applied in order to identify populations actively participating in 4-chlorobiphenyl catabolism. We observed that naringin and limonene in soil foster mainly populations of Hydrogenophaga spp., caffeic acid Burkholderia spp. and Pseudoxanthomonas spp. None of these populations were detected among 4-chlorobiphenyl utilizers in non-amended soil. Similarly, the degradation of individual PCB congeners was influenced by the addition of different plant compounds. Residual content of PCBs was lowest after treating the soil with naringin. Addition of caffeic acid resulted in comparable decrease of total PCBs with non-amended soil; however, higher substituted congeners were more degraded after caffeic acid treatment compared to all other treatments. Finally, it appears that plant secondary metabolites have a strong effect on the bacterial community structure, activity, and associated degradative ability.

The fungus Geotrichum candidum 4013 produces two types of lipases (extracellular and cell-bound). Both enzymes were tested for their hydrolytic ability to p-nitrophenyl esters and compounds having a structure similar to the original substrate (triacylglycerols). Higher lipolytic activity of extracellular lipase was observed when triacylglycerols of medium- (C12) and long- (C18) chain fatty acids were used as substrates. Cell-bound lipase preferentially hydrolysed trimyristate (C14). The differences in the abilities of these two enzymes to hydrolyse p-nitrophenyl esters were observed as well. The order of extracellular lipase hydrolysis relation velocity was as follows: p-nitrophenyl decanoate > p-nitrophenyl caprylate > p-nitrophenyl laurate > p-nitrophenyl palmitate > p-nitrophenyl stearate. The cell-bound lipase indicates preference for p-nitrophenyl palmitate. The most striking differences in the ratios between the activity of both lipases (extracellular : cell-bound) towards different fatty acid methyl esters were 2.2 towards methyl hexanoate and 0.46 towards methyl stearate (C18). The Michaelis constant (K(m) ) and maximum reaction rate (V(max) ) for p-nitrophenyl palmitate hydrolysis of cell-bound lipase were significantly higher (K(m) 2.462 mM and V(max) 0.210 U/g/min) than those of extracellular lipase (K(m) 0.406 mM and V(max) 0.006 U/g/min).

Two types of lipases (extracellular and cell-bound) were produced by Geotrichum candidum 4013 in liquid medium and were used as biocatalysts in blackcurrant oil hydrolysis. Reaction products were analysed for the degree of conversion from which enzyme activity was evaluated, and the composition of free fatty acids was compared to the composition of oil substrate. The enzyme activity was measured also before and after the reaction in SC-CO 2 . The fatty acid composition of the acids liberated from oil by hydrolysis suggests a specificity of the cell-bound and extracellular enzymes from Geotrichum candidum 4013. The extracellular lipase displays low selectivity to the polyunsaturated fatty acids, and the cell-bound lipase possesses selectivity to the saturated fatty acids. Enantioselectivity of the tested processes achieved with both induced enzymes was high (from 43 to 242). The activity of all enzymes has markedly increased after their exposure to SC-CO 2 . The treatment of enzymes by SC-CO 2 could be easy-to-use approaches to improve the efficiency of enzymatic reactions.

A highly selective whole cell optical biosensor for semi-quantitative detection of polychlorinated biphenyls (PCBs) with three chlorine substitutions is described. The biosensor is based on the formation of yellow meta ring fission products by silica entrapped cells. The reusable whole cell biosensor (WCB) was prepared by immobilizing cells of Pseudomonas sp. P2 in a silica matrix containing biphenyl 0.01 mg g−1 gel. Whole cell biosensors were exposed to 17 individual PCB congeners, or to the commercial PCB mixture Delor 103 (D103), toluene, xylene, naphthalene, 1-methylnaphthalene, anthracene, pyrene, phenanthrene, or dibenzofuran. The results show that silica entrapped cells produce yellow meta ring-fission products (absorbance λmax = 398 nm) selectively in the presence of three PCB congeners: 2,3,4′-trichlorobiphenyl, 2,4,4′-trichlorobiphenyl, and 2,5,4′-trichlorobiphenyl, and also with the commercial mixture Delor 103. PCB detection was not influenced by anthracene, phenanthrene, or pyrene. Naphthalene, toluene, 1-methylnaphthalene, and xylene decreased the production of yellow intermediates. Dibenzorufan was metabolized to an orange metabolite that interfered with PCB detection. The WCB's detection limit was 0.5 mgD103 l−1 and 0.2 mg2,4,4′CB l−1, repeatability ±10%, reusability 4 times and 2 weeks storage stability were demonstrated. Mineral oil and two soil samples from a landfill were analysed and compared by WCB and GC-ECD. This confirmed the ability of WCB to be used in screening tests.

Summary. Background: Carboxypeptidase N (CPN) is a constitutively active basic carboxypeptidase sharing specificity with activated thrombin-activable fibrinolysis inhibitor (TAFIa). Generally, CPN is regarded as being non-antifibrinolytic. However, this assumption has not been thoroughly investigated, particularly with respect to long-term antifibrinolysis. In addition, a recent report has shown that plasmin cleavage increases the catalytic activity of CPN. Therefore, we investigated the antifibrinolytic properties of CPN and plasmin-cleaved CPN (CPNc). Methods: CPN was incubated with plasmin for various periods of time and the prolongation of clot lysis at various concentrations of CPN/CPNc mixture was investigated in TAFI-depleted plasma. CPN cleavage was analyzed by electrophoresis and catalytic activity was determined by monitoring cleavage of the small substrate, FA-Ala-Lys. Results: CPN exhibited antifibrinolytic properties in plasma clot lysis assays when present at supraphysiological concentrations. Depletion of CPN from plasma decreased the lysis time of clots formed from minimally diluted plasma at low tissue-type plasminogen activator (t-PA) concentrations. Plasmin cleavage of CPN markedly increased the antifibrinolytic properties. CPN and CPNc prolonged lysis in a non-saturable, dose-dependent, and t-PA-dependent manner. At sufficient concentration, CPN and CPNc prolonged lysis at least forty-fivefold. CPNc was 700% more antifibrinolytic than CPN but only 7% more active toward FA-Ala-Lys. The active site inhibitor GEMSA eliminated the antifibrinolytic effects of CPN and CPNc. Antifibrinolytic activity correlated with cleavage of active and/or regulatory subunits, presumably generating heterodimeric CPNc. Conclusions: Limited proteolysis of CPN by plasmin generates an enzyme with greatly increased antifibrinolytic properties. We speculate that (patho)physiological proteolysis of CPN may generate a long-term antifibrinolytic enzyme.

We chose the larvae of fleshfly Sarcophaga bullata to map the peptide and protein immune response. The hemolymph of the third-instar larvae of S. bullata was used for isolation. The larvae were injected with bacterial suspension to induce an antimicrobial response. The hemolymph was separated into crude fractions, which were subdivided by RP-HPLC, gel electrophoresis, and free-flow electrophoresis. In several fractions, we determined significant antimicrobial activities against the pathogenic bacteria Escherichia coli, Staphylococcus aureus, or Pseudomonas aeruginosa. Among antimicrobially active compounds we identified dipeptide β-alanyl- L-tyrosine, protein transferrin, and two variants of peptide sapecin. We also partially characterized two novel antimicrobially active polypeptides; odorant-binding protein 99b, and a peptide which remains unidentified. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.

The present study is intended to determine metabolites of 12 dichlorinated, seven trichlorinated, five tetrachlorinated and one pentachlorinated PCB congener transformed by black nightshade ( Solanum nigrum ) hairy root culture SNC-9O. Free hydroxylated PCB metabolites were identified based on the mass spectra characteristics after gas chromatography separation. The number of metabolites decreases with an increasing number of chlorine atoms per molecule of PCB. Dichlorinated PCBs lead always to at least two metabolites. In the case of PCB 9 some metabolites could be identified by comparing their RF values due to available standards. The 2′,5′-dichloro-2-biphenylol, 2′,5′-dichloro-3-biphenylol and 2′,5′-dichloro-4-biphenylol, present as the main metabolite, were found in biomass of SNC-9O hairy root culture. Two monochlorinated biphenylols were found in biomass of SNC-9O degrading PCB 9 congener. It was the only case when metabolites with decreased number of chlorine atoms compared to parent PCB were found. Trichlorinated PCBs mostly lead to a lower number of metabolites but tetrachlorinated and pentachlorinated PCBs mostly did not give any metabolites. In the media, only traces of metabolites were found in sporadic cases, so exudation of unbound biphenylols from the cells is not expected.

Plant-microbial interactions within rhizosphere can evolve beneficial effect on degradation or increased accumulation of organic and inorganic contaminants. Our study shows the possibility of additional metabolic interactions between bacteria and plants in contaminated environment on level of their intermediates and their transformation. On example of model contaminants – PCBs, we give more detailed information about abilities of biological systems to metabolise original xenobiotics and also their intermediates and products. The enzymes of bacterial biphenyl operon were able to metabolise intermediates of plant PCB transformation namely 2-chloro-4-hydroxy biphenyl (2Cl-4OHBP) and 3-chloro-4-hydroxybiphenyl (3Cl-4OHBP). In case of other tested hydroxylated chlorobiphenyls the mode of oxygenation as well as the stability of the metabolites produced, greatly differed depending on the type of substituents. Similarly plant cells were able to metabolize, in limited extent, bacterial products of PCB degradation – chlorobenzoates (CBAs). From the four tested plant species tobacco, horseradish, nightshade and alfalfa showed significant transformation abilities only horseradish and black nightshade. Both metabolized in 2 weeks more than 90% of 2-chlorobenzoate and 20–40% of 2,3-; 2,4-; 2,5- and 2,6-dichlorobenzoates.

Substrate specificity (typoselectivity), regioselectivity and hydrolytic activity of induced lipases from three strains (4012, 4013, 4166) of Geotrichum candidum and that of Geotrichum ludwigii (48) were investigated. The lipases were induced in two types of culture media, of which the medium containing peptone as nitrogen source was proved to give better results. Olive oil was employed as inductor for the lipase activity. Activated lipases represented mostly extracelullar lipases, which penetrated through cellular membrane into medium. The activity of cell-bound lipase was also determined. Most of lipases belong to the group of specific lipases able to hydrolyse ester bonds in the positions sn-1 and sn-3 ester of triacylglycerols (1,3-selective lipases) and display specificity to saturated fatty acids. All activated lipases from Geotrichum sp., extracellular and cell-bound, were used as biocatalyst in the blackcurrant oil hydrolysis.

An extracellular alpha-d-galactosidase from Talaromyces flavus CCF 2686 with extremely broad and unusual acceptor specificity is produced exclusively in the presence of the specific inducer--6-deoxy-D-glucose (quinovose). The procedure for the preparation of this very expensive substance has been modified and optimized. Surprisingly, any of other common alpha-D-galactosidase inducers or substrates, e.g., D-galactose, melibiose and raffinose, did not stimulate its production. The crude alpha-D-galactosidase preparation was purified by anion-exchange chromatography and three isoenzymes with different substrate specificities were identified. The main isoenzyme (alphaGal1) was further purified by cation-exchange chromatography and fully characterized. When compared with other alpha-galactosidases and also with other isoenzymes produced by T. flavus, it showed a markedly different regioselectivity and also negligible hydrolytic activity towards melibiose. Moreover, it was active on polymeric substrates (locust bean gum, guar gum) and significantly inhibited by alpha-D-galactopyranosyl azide, D-galactose, D-xylose, melibiose, methyl alpha- and beta-D-galactopyranoside and lactose.

Aspergillus niger K10 cultivated on 2-cyanopyridine produced high levels of an intracellular nitrilase, which was partially purified (18.6-fold) with a 24% yield. The N-terminal amino acid sequence of the enzyme was highly homologous with that of a putative nitrilase from Aspergillus fumigatus Af293. The enzyme was copurified with two proteins, the N-terminal amino acid sequences of which revealed high homology with those of hsp60 and an ubiquitin-conjugating enzyme. The nitrilase exhibited maximum activity (91.6 U mg(-1)) at 45 degrees C and pH 8.0. Its preferred substrates, in the descending order, were 4-cyanopyridine, benzonitrile, 1,4-dicyanobenzene, thiophen-2-acetonitrile, 3-chlorobenzonitrile, 3-cyanopyridine, and 4-chlorobenzonitrile. Formation of amides as by-products was most intensive, in the descending order, for 2-cyanopyridine, 4-chlorobenzonitrile, 4-cyanopyridine, and 1,4-dicyanobenzene. The enzyme stability was markedly improved in the presence of D: -sorbitol or xylitol (20% w/v each). p-Hydroxymercuribenzoate and heavy metal ions were the most powerful inhibitors of the enzyme.

The transglycosylation potential of the extracellular α-d-galactosidase from the filamentous fungus Talaromyces flavus CCF 2686, chosen as the best enzyme from the screening, was investigated using a series of sterically hindered alcohols (primary, secondary and tertiary) as galactosyl acceptors. Nine alkyl α-d-galactopyranosides derived from the following alcohols – tert-butyl alcohol, 2-methyl-2-butyl alcohol, 2-methyl-1-propyl alcohol, 2,2,2-trifluoroethyl alcohol, 2-propyn-1-ol, n-pentyl alcohol, 3,5-dihydroxybenzyl alcohol, 1-phenylethyl alcohol and 1,4-dithio-dl-threitol – were prepared on a semi-preparative scale. This demonstrates a broad synthetic potential of the T. flavus α-d-galactosidase that has not been observed with another enzyme tested. Moreover, this enzyme exhibits good transglycosylation yields (6–34%). The enzymatic synthesis of tert-butyl α-d-galactopyranoside by transglycosylation was studied in detail.

The abundance, identities, and degradation abilities of indigenous polychlorinated biphenyl (PCB)-degrading bacteria associated with five species of mature trees growing naturally in a contaminated site were investigated to identify plants that enhance the microbial PCB degradation potential in soil. Culturable PCB degraders were associated with every plant species examined in both the rhizosphere and root zone, which was defined as the bulk soil in which the plant was rooted. Significantly higher numbers of PCB degraders (2.7- to 56.7-fold-higher means) were detected in the root zones of Austrian pine ( Pinus nigra ) and goat willow ( Salix caprea ) than in the root zones of other plants or non-root-containing soil in certain seasons and at certain soil depths. The majority of culturable PCB degraders throughout the site and the majority of culturable PCB degraders associated with plants were identified as members of the genus Rhodococcus by 16S rRNA gene sequence analysis. Other taxa of PCB-degrading bacteria included members of the genera Luteibacter and Williamsia , which have not previously been shown to include PCB degraders. PCB degradation assays revealed that some isolates from the site have broad congener specificities; these isolates included one Rhodococcus strain that exhibited degradation abilities similar to those of Burkholderia xenovorans LB400. Isolates with broad congener specificity were widespread at the site, including in the biostimulated root zone of willow. The apparent association of certain plant species with increased abundance of indigenous PCB degraders, including organisms with outstanding degradation abilities, throughout the root zone supports the notion that biostimulation through rhizoremediation is a promising strategy for enhancing PCB degradation in situ.

Extracts from Arabidopsis thaliana leaves and inflorescence stalks and from Lepidium sativa (Brassicaceae) seedlings were analysed by HPLC-MS-SIM and by five isoflavonoid-specific ELISA methods after the HPLC fractionation of samples, in order to determine presence of isoflavonoids. Individual ELISAs were specific for daidzein, genistein, biochanin A and for their derivatives substituted either at the 4'- or at the 7- positions. Both analytical approaches revealed homologous spectra of isoflavonoids in both plant species. As the ononin specific immunoassay was not available this compound was only detected by HPLC-MS. Formononetin and prunetin represented the main aglycones followed by biochanin A, daidzein and genistein; sissotrin was the most abundant isoflavonoid glycoside followed by ononin, daidzin and genistin. The content of individual compounds ranged from a few micrograms up to 2.2 mg kg(-1) (dry weight). Expression profiles of A. thaliana genes homologous to enzymes involved in isoflavonoid synthesis and metabolism were extracted from publicly available transcriptomic datasets for various tissues. Genes likely to be involved in important steps of the isoflavonoid metabolism in A. thaliana were identified. However, in accord with the previously published data, no homologue to isoflavone synthases known from the Fabaceae plants was found. These aryl migrating enzymes belong to the CYP93C family that is absent in A. thaliana. We conclude that another gene must be responsible for biosynthesis of the isoflavone skeleton in Brassicaceae.

The Bordetella adenylate cyclase toxoid (CyaA) targets cells expressing the alphaMbeta2 integrin receptor CD11b/CD18 (CR3 or Mac-1) and can penetrate into cytosol of professional antigen-presenting cells, such as dendritic cells. This allows us to use CyaA for delivery of passenger antigens into the cytosolic pathway of processing and MHC class I-restricted presentation, which can promote induction of antigen-specific CD8+ cytotoxic T-lymphocyte immune responses. We show here that vaccination with a genetically detoxified CyaA336/E7 protein, carrying the full-length oncoprotein E7 of the human papilloma virus 16 inserted at position 336 of the cell-invasive AC domain of CyaA, induces an E7-specific CD8+ T-cell immune response and confers on mice protective, as well as therapeutic immunity against challenge with TC-1 tumor cells expressing the E7 oncoprotein. The therapeutic efficacy of priming with the CyaA336/E7 vaccine could further be enhanced by a heterologous booster immunization with a highly attenuated modified vaccinia virus Ankara (MVA) expressing the E7 protein fused to the lysosome-associated membrane protein (LAMP1). These results establish the potential of CyaA as a new antigen delivery tool for prime/boost immunotherapy of tumors.

Epidermal growth factor (EGF) reduces apoptosis in primary cytotrophoblast (CT) in culture through two separate pathways: the extracellular signal related kinase (ERK) 1/2 and phosphatidyl inositol 3-kinase (PI-3 kinase) paths. Whether other pathways are involved in survival signalling is unknown. We here show that the c-Jun NH2 terminal kinase (JNK) and the mitogen activated kinase (MAPK) p38 are also activated by EGF as seen by increases in JNK and p38 phosphorylation. However, inhibition of JNK phosphorylation with the specific inhibitor SP600125 increases apoptosis in a manner refractory to the addition of EGF but inhibition of p38 phosphorylation with its specific inhibitor SB 203580 does not increase apoptosis. EGF also activates sphingosine kinase-1 (SPHK-1), which converts sphingosine to sphingosine-1-phosphate, and its inhibition with dimethyl sphingosine (DMS) increased trophoblast death. Inhibition of SPHK-1 also did not affect EGF stimulated phosphorylation of PI-3 kinase, Akt, ERK1/2 or p38 but inhibition of PI-3 kinase with a specific inhibitor LY294002 partly (40%) inhibited the EGF-stimulated increase in SPHK-1 activity. We conclude that, in addition to the PI-3 kinase and ERK1/2 pathways, EGF acts through its receptor to stimulate JNK, p38 and SPHK-1 pathways, but that the JNK and SPHK-1, and not the p38, pathways are involved in suppressing apoptosis. This information provides evidence that EGF stimulates survival along multiple pathways that differ in trophoblast and other cell types.

In this study, we investigated adrenergic and photoneural regulation of p38MAPK phosphorylation in the rat pineal gland. Norepinephrine (NE), the endogenous neurotransmitter, dose-dependently increased the levels of phosphorylated MAPK kinase 3/6 (MKK3/6) and p38MAPK in rat pinealocytes. Time-course studies showed a gradual increase in MKK3/6 and p38MAPK phosphorylation that peaked between 1 and 2 h and persisted for 4 h post NE stimulation. In cells treated with NE for 2 and 4 h, the inclusion of prazosin or propranolol reduced NE-induced MKK3/6 and p38MAPK phosphorylation, indicating involvement of both α- and β-adrenergic receptors for the sustained response. Whereas treatment with dibutyryl cAMP or ionomycin mimicked the NE-induced MKK3/6 and p38MAPK phosphorylation, neither dibutyryl cGMP nor 4β-phorbol 12-myristate 13-acetate had an effect. The NE-induced increase in MKK3/6 and p38MAPK phosphorylation was blocked by KT5720 (a protein kinase A inhibitor) and KN93 (a Ca2+/calmodulin-dependent kinase inhibitor), but not by KT5823 (a protein kinase G inhibitor) or calphostin C (a protein kinase C inhibitor). In animals housed under a lighting regimen with 12 h of light, MKK3/6 and p38MAPK phosphorylation increased in the rat pineal gland at zeitgeber time 18. The nocturnal increase in p38MAPK phosphorylation was blocked by exposing the animal to constant light and reduced by treatment with propranolol, a β-adrenergic blocker. Together, our results indicate that activation of p38MAPK is under photoneural control in the rat pineal gland and that protein kinase A and intracellular Ca2+ signaling pathways are involved in NE regulation of p38MAPK.

Cadmium accumulation and tolerance were tested using tobacco, Nicotiana tabacum L. var. Wisconsin 38 as the control (WSC) and a genetically modified line of the same variety bearing the transgene coding for the polyhistidine cluster, combined with yeast metallothionein (HisCUP). The screening test was conducted on sand nutrient medium with the addition of Knop's nutrient solution, modified by addition of various quantities of cadmium. Relative to the control, there were significant increases in cadmium accumulation in the aerial parts of HisCUP tobacco growing in cadmium concentrations of 0.2 and 0.6 mg cadmium l −1 nutrient solution. Addition of 5.4 mg cadmium l −1 induced symptoms of cadmium toxicity in the control tobacco, and the highest dose of cadmium was lethal. HisCUP showed increasing resistance to the stress response induced by cadmium. Experiments were continued in pots with two differently polluted soils. The cadmium content in the aerial biomass of transgenic tobacco increased by 45–75% compared with the control.

The regioselectivity of 20 extracellular β- N -acetylhexosaminidases of fungal origin was screened in the reverse hydrolysis with 2-acetamido-2-deoxy- d -glucopyranose. Most of the enzymes used yielded 2-acetamido-2-deoxy-β- d -glucopyranosyl-(1→4)-2-acetamido-2-deoxy- d -glucopyranose ( 3 ) and 2-acetamido-2-deoxy-β- d -glucopyranosyl-(1→6)-2-acetamido-2-deoxy- d -glucopyranose ( 4 ). So far unknown product of enzymatic condensation, 2-acetamido-2-deoxy-β- d -glucopyranosyl-(1→3)-2-acetamido-2-deoxy- d -glucopyranose ( 2 ) was synthesised using the β- N -acetylhexosaminidases from Penicillium funiculosum CCF 1994, P. funiculosum CCF 2325 and Aspergillus tamarii CCF 1665. Addition of salts ((NH 4 ) 2 SO 4 or MgSO 4 (0.1–1.0 M)) to the reaction increased the yields and also enhanced the β- N -acetylhexosaminidase regioselectivity.

A large panel of fungal β- N -acetylhexosaminidases was tested for the regioselectivity of the β-GlcNAc transfer onto galacto -type acceptors ( d -galactose, lactose, 2-acetamido-2-deoxy- d -galactopyranose). A unique, non-reducing disaccharide β- d -Glc p NAc-(1→1)-β- d -Gal p and trisaccharides β- d -Glc p NAc-(1→4)-β- d -Glc p NAc-(1→1)-β- d -Gal p , β- d -Gal p -(1→4)-β- d -Glc p -(1→1)-β- d -Glc p NAc and β- d -Gal p -(1→4)-α- d -Glc p -(1→1)-β- d -Glc p NAc were synthesised under the catalysis of the β- N -acetylhexosaminidase from the Aspergillus flavofurcatis CCF 3061 with d -galactose and lactose as acceptors. The use of 2-acetamido-2-deoxy- d -galactopyranose as an acceptor with the β- N -acetylhexosaminidases from A. flavofurcatis CCF 3061, A. oryzae CCF 1066 and A. tamarii CCF 1665 afforded only β- d -Glc p NAc-(1→6)- d -Gal p NAc.

Geotrichum ludwigii , Geotrichum candidum , and Saccharomyces cerevisiae whole cells were used for bioreduction of ethyl N -{2-{4-[(2-oxocyclohexyl)methyl]phenoxy}ethyl}carbamate 1 , an insect juvenile hormone bioanalog, to produce the stereoisomers of ethyl N -{2-{4-[(2-hydroxycyclohexyl)methyl]phenoxy}ethyl}carbamate 2 – 5 with as high as possible enantiomeric purity (>99% ee for 2 and 3 in several cases). Hydrophobic polymer Amberlite XAD-7 was used for potential modification of the reaction course mediated by isoenzymes present in the yeast whole cell bioreactors. Only stereoisomers 2 and 3 of ethyl N -{2-{4-[(2-hydroxycyclohexyl)methyl]phenoxy}ethyl}carbamate were obtained as major products of the studied enzymic process mediated by selected microorganisms.

The development of polyclonal antibody-based enzyme-linked immunosorbent assays (ELISA) for the determination of individual isoflavones, i.e. daidzein, genistein and biochanin and their homologues, is presented in this work. Isoflavone conjugates with bovine serum albumin were used as immunogens, coupled at the position C 7 and C 4’ via a carboxy methyl spacer. The developed ELISAs are highly specific, I50 values of the standard curves range between 0.3–1.2 ng/ml. The cross reactivities to other isoflavones are in acceptable range and the interference of non-isoflavonoid molecules is negligible. The immunoassays have been used for monitoring of changes in isoflavone levels in alimentary important plants, such as Medicago sativa, during germination; and during different vegetation stages of the Rutaceae family plants.

In failing myocytes, impaired E-C coupling is often associated with loss of t-tubules and appearance of orphaned calcium release units. Impairment of communication between Ca-channels of sarcolemma and of sarcoplasmic reticulum (SR) has been observed in non-failing stages of cardiac hypertrophy. We therefore studied the relationship between Ca-signaling and ultrastructure of dyadic junctions in early stages of myocardial injury.Myocardial injury (IMI) was induced by a single dose of isoproterenol (150 mg/kg, i.p.) in adult male rats. On day 15, isolated myocytes were studied using laser scanning fluorescence confocal microscopy: Ca-spikes were activated by whole-cell patch-clamp and t-tubules were visualized by di-8-ANEPPS. Ultrastructure of dyadic junctions was evaluated from electron-microscopic images.Our results show that remodeling of IMI myocytes transpired as increased proportion of longitudinal elements of tubular system as well as increased proportion of dyads with defective contact between the membranes of sarcolemma and SR; however, there was no actual loss of t-tubules and ultrastructure of t-tubules in dyads of IMI myocytes was similar to control (CTR). In parallel, Ca-spike activation was slower and less synchronized in IMI. In both CTR and IMI, distribution of latencies of Ca-spikes and the time profile of Ca-release flux measured from whole cells consisted of two components. The fraction of the slow component of calcium release in IMI was close to the fraction of dyads with defective contact between the membranes of sarcolemma and SR.We conclude that overload of cardiac myocytes of the working part of injured myocardium leads to damage of tubulo-reticular junctions of dyadic microdomains, which results in impairment of local calcium signaling.Support: APVV-0721-10, VEGA 2/047/14 and VEGA 2/0095/15

Villous trophoblasts undergo increased apoptosis and experience a wider gradient of oxygen tensions (pO(2)) in pregnancies complicated by intrauterine growth restriction. We hypothesize that pO(2)affects trophoblast apoptosis by altering survival signalling through the phosphatidylinositol-3 (PI-3)-kinase and mitogen activated protein kinase (MAPK) pathways. Cytotrophoblasts were cultured at pO(2)from

A novel route to chiral ferrocene derivatives involving the application of hydroxynitrile lyase from Hevea brasiliensis has been developed. The method allows the conversion of formylferrocene 1 and 1,1′-diformylferrocene 2 into their corresponding chiral cyanohydrins. (R)-(Cyanohydroxymethyl)ferrocene 3 and (R,R)-1,1′-bis(cyanohydroxymethyl)ferrocene 4 were obtained in high yield and stereochemical purity using this method. The full structural characterisation of the latter including the determination of diastereomeric purity and the assignment of the absolute configuration is disclosed.

5-Hydroxypiperidin-2-one is a versatile building block for the preparation of potentially biologically active compounds. We detail an enantioselective biocatalytic approach towards its synthesis using (S)-hydroxynitrile lyase (HNL)-mediated cyanohydrin formation, followed by hydrogenation. By adjusting the conditions of the latter step, we were able to obtain 5-hydroxypiperidinone-derived (bicyclic) N,N-acetals via an unprecedented reductive amination of the nitrile group, as well as form N-alkylated 5-hydroxypiperidinone in a single step from the same cyanohydrin intermediate.

An extracellular H2O2-requiring Remazol Brilliant Blue R (RBBR) decolorizing enzyme activity was detected after cultivation of cells of various plant species both in liquid medium and when growing on agar plates containing RBBR. Level of the enzyme activity was compared with the ability to metabolize polychlorinated biphenyls (PCBs). The ability to decolorize RBBR was tested in the presence and absence of PCBs. The cultures with high PCB-transforming activity proved to exhibit RBBR oxidase much more resistant towards the influence of PCBs. In addition low activities of lignin peroxidase (LiP) and manganese dependent peroxidase (MnP) were detected in medium and in plant cells. No correlation of MnP and LiP activities with PCB degradation could be found. The RBBR decolorization could be used as a rough screening method for plant cultures able to metabolize PCBs.

The degradation of Delor 103, a mixture of polychlorinated biphenyl (PCB) congeners, by Pseudomonas sp. P2, an indigenous soil bacterium was studied. In mineral medium with biphenyl as sole carbon source the extent of PCB degradation monitored by GC exceeded 70%. The efficiency of Delor 103 degradation by strain P2 was compared with that of Ralstonia eutropha H850. The addition of saccharose or agar improved PCB degradation, whereas the addition of glycerol or pyruvate substantially reduced the degradation efficiency. The presence of an amino acid mixture enhanced PCB degradation. The following chlorobenzoic acids (CBA): 2,5 CBA, 2,4 CBA, 4 CBA, 2 CBA and 2,5-diCBA were detected as metabolites of Delor 103, with 2,5-diCBA as the major product. Although 2,5-diCBA inhibited the growth of Pseudomonas sp. P2 the degradation of 2,5-diCBA was unaffected for upto 14 days.

Recently it has been shown that plants are able to transform polychlorinated biphenyls (PCBs) as well as polycyclic aromatic hydrocarbons (PAHs), but the knowledge of enzymes involved in these metabolic processes is limited. Plant peroxidases generally play an important role in plant metabolism. On the other hand, cytochrome P450 is involved in the detoxification of various xenobiotics in the cells of higher organisms. In this work, several in vitro cultures of different plant species were screened for their ability to transform PCBs or PAHs, and compared regarding their total extra- and intracellular peroxidase activity. Cultures with good transformation ability exhibited in the presence of xenobiotics the same or higher levels of peroxidases as the controls incubated without contaminants. Cultures with markedly lower peroxidase activity exhibited also lower PCB/PAH conversion in the presence of PCBs/PAHs. It was attempted to identify lignin peroxidase and Mn-peroxidase in plants, originally described in white rot fungi to be responsible for the degradation of PCBs and other environmental pollutants. In addition to different types of peroxidases, RBBR oxidase was also detected in plants. The decolourisation of RBBR during the growth on agar plates was used as a rough screening method for plant cells able to metabolise PCBs/PAHs efficiently. The exact type of transformation reaction (peroxidative or oxidative) was studied using various inhibitors and inducers of peroxidases and cytochrome P450. It was shown that both enzymatic systems are partially involved in the detoxification mechanism of chosen xenobiotics in plants.

Especially tailored transgenic plants were prepared for the purpose of phytoremediation. In the case of heavy metals, high accumulation in plants is the main requirement, particularly in the harvestable parts. Improvement in a plant's ability to tolerate heavy metals via the introduction of metallothionein (MT) genes has already been demonstrated by different authors. In this study, an additional metal binding domain to the implemented protein was introduced in order to further enhance the metal binding capacity. For this reason, gene coding a peptide containing six histidine moieties was combined with a CUP1 yeast metallothionein gene originating from Saccharomyces cerevisiae, which was introduced into tobacco plants using an Agrobacterium tumefaciens vector. Transformants selected on the basis of the kanamycine resistance were checked for the presence of transgenes by RNA isolation of aseptic plants and RT-PCR. The effectiveness of the obtained lines of genetically modified tobacco plants to accumulate heavy metals was tested on sand media with the addition of KNOP'S nutrient solution modified by the addition of cadmium (0.2 mg Cd/l as Cd (NO 3 ) 2 x 4 H 2 O), and compared with non-transformed control plants (the average of the controls was 16.9 mg Cd/kg of dry matter (DM) above ground and 14.3 mg Cd/kg DM in roots). The best performing line HisCUP-X accumulated 90% more Cd in above-ground parts (31.3 mg Cd/kg DM above ground, 10.6 mg Cd/kg DM in roots) during the six-week test period without visible differences in the growth characteristics. Increased translocation into the harvestable parts of the plant is considered as especially important.

The performance of ( S )-oxynitrilase from Hevea brasiliensis (HbHNL) has been investigated with several α- and β-substituted alkyl or alkoxy aldehydes and the results have been compared to the data previously obtained with the ( R )-specific enzyme from almonds (PaHNL). With both enzymes there was no chiral discrimination between the enantiomers of the racemic substrates, therefore this reaction cannot be used as a preparative method to achieve both the kinetic resolution of the starting racemic aldehyde and the production of diastereomerically pure (or enriched) cyanohydrins. Additionally, in comparison with the ( R )-PaHNL the ( S )-selective enzyme from Hevea gave products with higher de, but was more negatively effected by oxygenated substituents.

The effects of p38 mitogen-activated protein kinase (p38MAPK) inhibitors on the adrenergic-stimulated cyclic nucleotide production in rat pinealocytes were investigated. Treatment with SB202190 [4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)IH-imidazole] and SB203580 [4-(4-fluoropheny)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)IH-imidazole] (1–100 μM), two pyridinyl imidazole compounds that inhibit p38MAPK, as well as SB202474 [4-(ethyl)-2-(4-methoxyphenyl)-5-(4-pyridyl)IH-imidazole], an inactive analog, was effective in potentiating norepinephrine- and isoproterenol-stimulated cyclic AMP (cAMP) and cyclic GMP (cGMP) accumulation in a concentration-dependent manner. All three compounds caused a greater increase in the cGMP than the cAMP response, with SB202474 being substantially more potent than the two active analogs. At 100 μM, SB202474 potentiated the isoproterenol-stimulated cAMP and cGMP accumulation by 65 and 500%, respectively. Pharmacological studies indicated that the potentiating effect of SB202474 was independent of protein kinase C activation, intracellular calcium elevation, or serine/threonine phosphatase inhibition, three pathways known to potentiate the β-adrenergic-stimulated cyclic nucleotide responses in rat pinealocytes. In contrast, the potentiating effect of SB202474 was abolished in the presence of a phosphodiesterase inhibitor, isobutylmethylxanthine. At 100 μM, all three compounds inhibited cAMP- and cGMP-phosphodiesterase activities by 50 and 80%, respectively. These results suggest that the commonly used p38MAPK inhibitors can modulate cyclic nucleotide responses through phosphodiesterase inhibition, a mechanism that appears to be independent of p38MAPK inhibition.

Transformation of polychlorinated biphenyls was studied using different strains of in vitro cultured cells of horseradish (Armoracia rusticana L.). Time and concentration dependence of this process and production of intracellular and extracellular peroxidases were measured with differentiated shooty teratoma culture K54. The yield of PCB transformation and the viability of the cells were highly dependent on PCB concentration. 100 ppm PCB totally inhibited growth of the cells, and reduced their metabolism of xenobiotics. Experiments with a peroxidase (POX) inhibitor, propylgallate, and a cytochrome P450 inhibitor, aminobenztriazole, indicated the involvement of both enzymatic systems in PCB metabolism.

The ability of in vitro cultured cells of black nightshade, wheat, barley, soybean, tomato, mulberry and birch to grow in the presence of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) and to metabolise them was compared. No correlation was found between the resistance of the plants and removal of xenobiotics. Up to 20% of PCBs and over 90% of PAHs were removed by wheat cells from nutrient media in two weeks.