Determination and transferability of plasmid‐mediated antibiotic resistance genes of the bacteria isolated from rainbow trout

Antibiotic resistance and the presence of resistance genes (ARGs) were investigated in the bacteria isolated from rainbow trout (Oncorhynchus mykiss) from different trout farms located in Turkey. The most frequent types of antibiotic resistance were towards β‐lactams (cephalothin [70% of bacterial isolates], amoxicillin [63%], ampicillin [62%], ticarcillin [56%], aztreonam [51%]), macrolide [erythromycin, 68%] and sulphonamide [sulphamethoxazole, 51%]. Of bacterial isolates, 51% were multiple drug resistant (MDR), while 35% of the isolates were extensively drug resistant (XDR). None of isolates were pandrug resistant (PDR). The most common ARGs were ampC (36%) and sul1 (24%). The class 1 integron gene cassette was detected in 51% of the bacteria. There was a strong positive correlation between the antibiotic resistance rate and the presence of ARGs (r² = .932). Gene encodes bla_CTX‐M1, one of the extended spectrum beta‐lactamase enzymes, was first described in Aeromonas caviae, Photobacterium damselae, Pseudomonas luteola and Burkholderia cepacia. It was determined that 35% of the bacteria harboured at least one plasmid. Plasmid‐mediated ARGs were identified to be tetracyclines (tetA, tetB, tetC, tetD), sulphonamides (sul1, sul3) and β lactams (ampC, bla_pse). Thus, results suggest that ARG contamination situation deliberates resistance to tetracycline, aminoglycoside, chloramphenicol and sulphonamide. Therefore, the presence and activity of ARGs in fish and in environmental bacteria may play an important role in the spread of resistance genes among bacteria by transposition or integron gene cassettes.     

Cross-border molecular tracing of brucellosis in Europe

To assess the general impact of endemic countries on the re-emergence of brucellosis in non-endemic regions of the European Union, the genetic fingerprints of Brucella melitensis strains imported to Germany were compared to ovine strains from Turkey in a molecular epidemiological study. Genotyping of 66 Brucella strains (based on Multiple Locus of Variable number of tandem repeats Analysis) isolated from German travellers and Turkish immigrants living in Germany revealed epidemiological concordance with 20 sheep isolates originating from Eastern Anatolia, Turkey. In summary, cross-border molecular tracing confirmed brucellosis being a zoonosis of concern for European public health.     

A parasitological, molecular and serological survey of Hepatozoon canis infection in dogs around the Aegean coast of Turkey

Canine hepatozoonosis is caused by the tick-borne protozoon Hepatozoon spp. The prevalence of the infection in the Aegean coast of Turkey was investigated by examination of blood smear parasitology and polymerase chain reaction (PCR) using blood samples from 349 dogs collected from Central Aydin, Kusadasi, Selcuk, Central Manisa, Bodrum and Marmaris within the Aegean coast of Turkey. The indirect fluorescent antibody test (IFAT) for the detection of Hepatozoon canis antibodies was also used to detect the exposure rate to H. canis. PCR amplifying a 666bp fragment of 18S rRNA gene of Hepatozoon spp. was used in the epidemiological survey. The prevalence of Hepatozoon spp. infection was 10.6% by blood smear parasitology and 25.8% by PCR. IFAT revealed that 36.8% of serum samples were positive for antibodies reactive with Hepatozoon spp. The PCR products of 18S rRNA gene of Hepatozoon spp. isolated from six infected dogs, one isolate originating from each of the six different locations, were sequenced. The results of sequence analysis indicate that they are closely related to Indian and Japanese isolates of H. canis. This is the first epidemiological study on the prevalence of H. canis infection in the dog, in Turkey.     

INFLUENCE OF ALUMINUM ON MINERAL NUTRIENT UPTAKE AND ACCUMULATION IN URTICA PILULIFERA L.

Pollutants can have detrimental effects on living organisms. They can cause toxicity, damaging cells, tissues and organs because of their high concentrations or activities. Plants provide a useful system for screening and monitoring environmental pollutants. Among pollutants, aluminum is considered as a primary growth limiting factor for plants resulting in decreased plant growth and development. Although considered to be a non-essential and highly toxic metal ion for growth and development, aluminum (Al) is easily absorbed by plants. Urticaceae family members have high nutrient requirements demonstrated by leaves containing high levels of calcium (Ca), iron (Fe), magnesium (Mg), and nitrogen (N). Urtica pilulifera is one of the important traditional medicinal plants in Turkey. In this study, U. pilulifera was used as a bioindicator to investigate the possible differences in the absorption and accumulation of mineral nutrients at different levels of the Al exposure and examine the mineral nutrition composition of U. pilulifera under Al stress. Also, some growth parameters (leaf-stem fresh and dry weights, root dry weights, stem lengths and leaf surface area) were investigated. U. pilulifera seedlings were grown for two months in growth-room conditions and watered with spiked Hoagland solution, which contained 0, 100, and 200 μM aluminium chloride (AlCl₃). It was observed that macro- and micro-nutritional status of roots and leaves was altered by Al exposure. The concentrations of some macro- and micronutrients were reduced while concentrations of others were increased by excess of Al. Some macro- and micronutrients were increased at low level of Al whereas reductions were observed at high level of Al, and vice versa. The patterns were dependent on the macro- or micronutrient and the plant part.     

Analysis of EST-SSRs in silver birch (<Emphasis Type="Italic">Betula pendula</Emphasis> Roth.)

Simple sequence repeats (SSRs) defined as sequence repeat units between 1 and 6 bp occur abundantly in both coding and non-coding regions in eukaryotic genomes and these repeats can affect gene expression. In this study, ESTs (expressed sequence tags) of Betula pendula (silver birch) were analyzed for in silico mining of EST-SSRs, protein annotation, open reading frames (ORFs), designing primers, and identifying codon repetitions. In B. pendula, the frequency of ESTs containing SSRs was 7.8 % with an average of 1SSR/4. 78 kb of EST sequences. A total of 188 SSRs was identified by using MISA software and di-nucleotide SSR motifs (65.9 %) were found to be the most abundant type of repeat motif followed by tri- (27.1 %), tetra- (4.8 %), and penta- (2.2 %) motifs. Based on ORF analysis, 175 of 178 sequences were predicted as ORFs and the most frequent SSRs were detected in 5′ UTR (58.43 %), followed by in ORF (31.46 %) and in 3′ UTR (8.43 %). 102 of 178 ESTs were annotated as ribosomal protein, transport protein, membrane protein, carrier protein, binding protein, and transferase protein. For a total of 102 SSRs (57.3 %) with significant matches, a set of 102 primers (100 %) with forward and reverse strands was designed by using Primer3 software. Serine (Ser, 19.6 %) was predominant in putative encoded amino acids and most of amino acids showed nonpolar (35.3 %) nature. Our data provide resources for B. pendula and can be useful for in silico comparative analyses of Betulaceae species, including SSR mining.     

Prevention of surface death of horse mackerel (Trachurus mediterraneus) larvae by the addition of egg white and camphor grain to rearing water

To prevent surface tension‐related deaths in horse mackerel larvae, Trachurus mediterraneus, camphor grain (CG; 26 and 52 mg L^?1 with and without ethanol) and chicken egg white (EW; 40 and 80 μL L^?1) were added to rearing water. Compared with the control groups, supplementation of EW (40–80 μL) and CG (52 mg L^?1, dissolved in ethanol) significantly improved the survivals of horse mackerel larvae (P<0.05). At the end of the 10 days after hatching, the survival rates of EW‐40 and EW‐80 were 64% and 72% respectively. No clear correlation was found between surface tension and survival rate.     

Disease of rainbow trout caused by Pseudomonas luteola

Bacteria isolated from rainbow trout, Oncorhynchus mykiss, kept in a farm, in Turkey. During the outbreak, 40% of the rainbow trout (10-40 g) died. Typical clinical signs were exophthalmia, dark pigmentation, hemorrhage at the base of the pectoral, pelvic, anal fins and around the vent. Internal signs were enlarged spleen, pale liver and intestine filled with yellowish fluid. Liver, kidney and spleen of diseased fish, were aseptically streaked on Tryptic Soy Agar. After incubation, pure cultured colonies were observed and biochemically characterized with API 20 NE and other biochemical tests. Cultured bacterial 16 S rDNA gene was sequenced. Based on biochemical characteristics and sequence of 16 S rRNA, the causative bacteria were identified as Pseudomonas luteola. This study reports the first P. luteola infection in fish.