Natalija Topić Popović, Slavko Kepec, Snježana P. Kazazić, Josip Barišić, Ivančica Strunjak-Perović, Sanja Babić and Rozelindra Čož-Rakovac
Wastewaters from a treatment plant discharging into a canal harboring fish may present sources of microbiological hazard for wild fish. Such fish, inhabiting microbiologically polluted bodies of water, can be contaminated by human pathogens and, if used for human consumption, may pose a risk to public health. Hence, in this work the aim was to identify tested strains from tissues of wild fish living in the receiving water bodies, captured from locations up to 12 km from the point of discharge of treated water of town Virovitica in order to assess the bacterial threat of the WWTP on fish and potentially on public health. A rather rich diversity of bacterial genera was isolated from gill tissues and internal organs. The most frequent isolate was Aeromonas hydrophila which has gained public health recognition as an opportunistic pathogen. Vibrio cholerae, an indicator bacterium for aquatic contamination, was retrieved from all investigated tissues. Opportunistic human pathogens as well as some zoonotic agents were also retrieved from fish tissues (Enterobacter amnigenus, Acinetobacter spp., Ochrobactrum anthropi, Pseudomonas aeruginosa, Flavimonas (Pseudomonas) oryzihabitans, Shewanella putrefaciens and others). Public health hazard is particularly pronounced regarding local recreational fishermen who fish out, handle and consume fish from respective waters.
Ivana Bošnjak, Ana Bielen, Sanja Babić, Lidija Šver, Natalija Topić Popović, Ivančica Strunjak-Perović, Rozelinda Čož-Rakovac and Roberta Sauerborn Klobučar
Multixenobiotic resistance (MXR) is an important mechanism of cellular efflux mediated by ATP binding cassette (ABC) transporters that bind and actively remove toxic substrates from the cell. This study was the first to identify ABC transporter P-glycoprotein (P-gp/ABCB1) as a representative of the MXR phenotype in earthworm (Eisenia fetida). The identified partial cDNA sequence of ABCB1 overlapped with ABCB1 homologues of other organisms from 58.5 % to 72.5 %. We also studied the effect of five modulators (verapamil, cyclosporine A, MK571, probenecid, and orthovanadate) on the earthworm’s MXR activity by measuring the accumulation of model substrates rhodamine B and rhodamine 123 in whole body tissue of the adult earthworm. MK571, orthovanadate, and verapamil significantly inhibited MXR activity, and rhodamine 123 turned out to better reflect MXR activity in that species than rhodamine B. Our results show that E. fetida can serve well as a test organism for environmental pollutants that inhibit MXR activity.