Latest Publications

@article{uhlik_bacterial_2014,

title = {Bacterial acquisition of hexachlorobenzene-derived carbon in contaminated soil.},

author = {Ondrej Uhlik and Michal Strejcek and Jan Vondracek and Lucie Musilova and Jakub Ridl and Petra Lovecka and Tomas Macek},

doi = {10.1016/j.chemosphere.2014.04.110},

issn = {1879-1298 0045-6535},

year  = {2014},

date = {2014-10-01},

journal = {Chemosphere},

volume = {113},

pages = {141–145},

abstract = {Pesticides are a class of xenobiotics intentionally released into the environment. Hexachlorobenzene (HCB) was used as a fungicide from 1945, leaving behind many contaminated sites. Very few studies have examined the biodegradation of HCB or the fate of HCB-derived carbon. Here we report that certain bacterial populations are capable of deriving carbon from HCB in contaminated soil under aerobic conditions. These populations are primarily Proteobacteria, including Methylobacterium and Pseudomonas, which predominated as detected by stable isotope probing (SIP) and 16S rRNA gene amplicon pyrosequencing. Due to the nature of SIP, which can be used as a functional method solely for assimilatory processes, it is not possible to elucidate whether these populations metabolized directly HCB or intermediates of its metabolism produced by different populations. The possibility exists that HCB is degraded via the formation of pentachlorophenol (PCP), which is further mineralized. With this in mind, we designed primers to amplify PCP 4-monooxygenase-coding sequences based on the available pcpB gene sequence from Methylobacterium radiotolerans JCM 2831. Based on 16S rRNA gene analysis, organisms closely related to this strain were detected in (13)C-labeled DNA. Using the designed primers, we were able to amplify pcpB genes in both total community DNA and (13)C-DNA. This indicates that HCB might be transformed into PCP before it gets assimilated. In summary, this study is the first report on which bacterial populations benefit from carbon originating in the pesticide HCB in a contaminated soil.},

note = {Place: England},

keywords = {*Soil Microbiology, 16S rRNA genes, 16S/genetics, Amplicon pyrosequencing, Biodegradation, Bioremediation, Carbon Isotopes/metabolism, Czech Republic, DNA, DNA Primers, Environmental, Hexachlorobenzene/chemistry/*metabolism, Isotope Labeling, Methylobacterium/*metabolism, Mixed Function Oxygenases/metabolism, Molecular Structure, Pentachlorophenol 4-monooxygenase, Pentachlorophenol/chemistry/metabolism, Pesticides, Pseudomonas/*metabolism, Real-Time Polymerase Chain Reaction, Ribosomal, RNA, Sequence Analysis, Soil Pollutants/*metabolism, Stable isotope probing},

pubstate = {published},

tppubtype = {article}

}

@article{jendzelovsky_drug_2009,

title = {Drug efflux transporters, MRP1 and BCRP, affect the outcome of hypericin-mediated photodynamic therapy in HT-29 adenocarcinoma cells.},

author = {Rastislav Jendzelovský and Jaromír Mikes and Ján Koval' and Karel Soucek and Jirina Procházková and Martin Kello and Veronika Sacková and Jirina Hofmanová and Alois Kozubík and Peter Fedorocko},

doi = {10.1039/b9pp00086k},

issn = {1474-9092 1474-905X},

year  = {2009},

date = {2009-12-01},

journal = {Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology},

volume = {8},

number = {12},

pages = {1716–1723},

abstract = {Photodynamic therapy (PDT) is a flexible multi-target therapeutic approach. One of the main requirements of successful PDT is sufficient intracellular concentration of an applicable photosensitizer. Mechanisms of anticancer drug elimination by tumour cells are mostly linked to the elevated expression and activity of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), breast cancer resistance protein (BCRP) and P450 monooxygenases. The interaction of hypericin with this cell drug-defence system is still unclear. We report here for the first time increased activity of MRP1 and BCRP in HT-29 colon cancer cells treated with hypericin per se. On the contrary, pre-treatment with proadifen (SKF525A) affected the function of MRP1 and BCRP leading to increased hypericin content, which might indicate a possible link between proadifen and these ABC transporter proteins. Subsequent enhanced intracellular oxidative stress was accompanied by loss of mitochondrial membrane potential, activation of caspase-9 and -3, PARP cleavage and onset of apoptosis. In conclusion, our study suggests that drug efflux transporters MRP1 and BCRP affect the pharmacokinetics of hypericin in HT-29 colon adenocarcinoma cells, and the action of hypericin-mediated PDT (HY-PDT) should be modulated by pre-treatment with their specific inhibitors.},

note = {Place: England},

keywords = {Adenocarcinoma/*drug therapy/secondary, Anthracenes, ATP Binding Cassette Transporter, ATP-Binding Cassette Transporters/*metabolism, Caspase 3/metabolism, Caspase 9/metabolism, Colonic Neoplasms/*drug therapy, Enzyme Inhibitors/pharmacology, HT29 Cells, Humans, Light, Member 1/metabolism, Member 2, Membrane Potential, Mitochondrial/drug effects, Mixed Function Oxygenases/metabolism, Multidrug Resistance-Associated Proteins/*metabolism, Neoplasm Proteins/*metabolism, Perylene/*analogs & derivatives/pharmacology, Photochemotherapy, Photosensitizing Agents/*pharmacology, Proadifen/pharmacology, Reactive Oxygen Species/metabolism, Subfamily B, Subfamily G},

pubstate = {published},

tppubtype = {article}

}