Chlorine is deployed worldwide to clean waters and prevent water-originated illnesses. However, chlorine has a limited disinfection capacity against biofilms. Microorganisms form biofilms to protect themselves from biological threats such as disinfectant chemicals. Pseudomonas aeruginosa is an opportunistic pathogen and its biofilm form attaches to surfaces, living buried into exopolysaccharides, can be present in all watery environments including tap water and drinking water. This research aimed to study the biofilm trigger mechanism of the opportunistic pathogen P. aeruginosa PAO1 strain, which is known to form biofilm in water supply systems and human body, under chlorine stress levels. In addition to biofilm staining, certain genes that are relevant to the stress condition were selected for gene expression analysis. The bacteria cultures were grown under chlorine stress with concentrations of 0.5, 0.7 and 1 mg/l. Six gene regions were determined related to biofilm and stress response: rpoS, bifA, migA, katB, soxR, and algC. Biofilm formation was analyzed by basic fuchsin staining, and gene expressions were quantified by quantitative real-time PCR. According to the results, highest biofilm production was observed in P. aeruginosa PAO1 wild strain under no stress conditions. Higher biofilm amounts were observed for bacteria under 0.5 and 0.7 mg/l chlorine stress compared to 1 mg/l chlorine stress.

Antidiabetic therapy was found to increase adiposity in omental and subcutaneous fat. Further research is needed with larger samples to explore the exact role of FTO in obesity.

Heat shock proteins are a family of highly conserved cellular proteins present in all organisms including fish. Fish represent an ideal model organism to understand the regulation and functional significance of heat shock proteins (Hsps). The mechanism regulating the expression of Hsp genes in fish have not been studied in detail. In this review, the function, genomic structure and environmental adaptation of the major fish Hsps were discussed. Future research evaluating the functional genomics of Hsps in fish will provide substantial insight into the physiological and ecological roles of these highly conserved proteins.

Over the past decade aquatic environments have become more contaminated by insecticides.Insecticides have a toxic effect on aquatic organisms and they become a part of the food chain by accumulation. Therefore it is very important to study the effects of subchronic exposure to environmental concentrations of insecticides on aquatic organisms. The aim of this review is to investigate different effects of insecticide groups on aquatic organisms in aquatic environment.

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