Project description:Complex microbial metabolism is key to taste formation in high-quality fish sauce during fermentation. To guide quality supervising and targeted regulation, we analyzed the function of microbial flora during fermentation based on a previous metagenomic database. Most of the identified genes involved in metabolic functions showed an upward trend in abundance during fermentation. In total, 571 proteins extracted from fish sauce at different fermentation stages were identified. The proteins were mainly derived from Halanaerobium, Psychrobacter, Photobacterium, and Tetragenococcus. Functional annotation showed 15 pathways related to amino acid metabolism, including alanine, aspartate, glutamate, and histidine metabolism; lysine degradation; and arginine biosynthesis.
Project description:Fireflies and their luminous courtships have inspired centuries of scientific study. Today firefly luciferase is widely used in biotechnology, but the evolutionary origin of bioluminescence within beetles remains unclear. To shed light on this long-standing question, we sequenced the genomes of two firefly species that diverged over 100 million-years-ago: the North American Photinus pyralis and Japanese Aquatica lateralis. To compare bioluminescent origins, we also sequenced the genome of a related click beetle, the Caribbean Ignelater luminosus, with bioluminescent biochemistry near-identical to fireflies, but anatomically unique light organs, suggesting the intriguing hypothesis of parallel gains of bioluminescence. Our analyses support independent gains of bioluminescence in fireflies and click beetles, and provide new insights into the genes, chemical defenses, and symbionts that evolved alongside their luminous lifestyle.
Project description:Transcriptomics ananlysis of olfactory organs of Atlantic salmon. Controls/untreated (C) fish were compared to fish that were exposed to low (L) or high (H) concentrations of hydrogen sulphide.
Project description:Enteropathogenic Yersinia enterocolitica and Yersinia pseudotuberculosis share many traits in terms of infections they cause, but their epidemiology and ecology seem to differ in many ways. Pigs are the only known reservoir for Y. enterocolitica 4/O:3 strains while Y. pseudotuberculosis strains have been isolated from variety of sources including fresh vegetables and wild animals. A comparative genomic hybridization (CGH) analysis with a DNA microarray based on three Yersinia enterocolitica and four Yersinia pseudotuberculosis genomes was conducted to shed light on genomic differences between the enteropathogenic Yersinia. In total 99 strains isolated from various sources were hybridized and analyzed.
Project description:This experiment was set up to evaluate the effect of the duration of a short photoperiod (winter-like conditions, 8 hours light, 14 hours dark) on the smolt transcriptome in liver and gill. Fish were kept at constant light before fish were split between treatment tank or control tanks. Treatment tanks either experienced 2 weeks of short photoperiod or 8 weeks of short photoperiod. The control fish were kept in constant winter-like conditions. After winter, the fish were brought back to constant light for 4 weeks. Sampling was done before transition to short photoperiod, at the end of winter period and four weeks after transition back to constant light. Control fish were sampled at the same time points as the treatment group.
Project description:Using criteria based on known examples, we identified approximately 1.7 million and 2.4 million sequences encoding putative miRNA precursor (stem-loop) structures in the mouse and human genomes, respectively, as well as large numbers of such structures in the genomes of fish, fruitfly and nematode worm. These predictions were then tested using high density custom microarrays containing modified oligonucleotides interrogated with purified small RNAs from different tissues. We found that 19% of 4,006 randomly chosen mouse predictions and 40% of 1,859 randomly chosen human predictions gave positive signals with small RNA isolated from whole 10-12 day embryos and a mixture of brain and testis, respectively, 84% of which hybridized to only one strand of the predicted stem-loop structure, whereas only 2% and 12% of equivalent random mouse and human predictions were positive. There was no difference in the validation rates between sequences exhibiting conservation and those that did not. High validation rates were also observed with predictions from fish, fly and worm genomes. Northern blot analysis of the array-positive mouse predictions confirmed that the vast majority of these sequences were detectable as small RNAs whose sizes ranged from 20-110 nucleotides. Taking into account false negative rates of the prediction and detection of known miRNAs, and assuming that this holds for other small RNAs, we estimate that there are 1 million small RNAs expressed in mouse and 3 million small RNAs in human. Keywords: genomic survey of small RNAs