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Mitochondrial genomes were sequenced from five Raja pulchra individuals, and single-nucleotide polymorphisms (SNPs) were identified by comparing previously announced sequences in this study. Total 117 SNPs were detected and they were present in 2 rRNA genes, 9 tRNA genes, 13 protein coding genes and non-coding region. One deleted polymorphic site, which was located in 16S rRNA gene, was observed in two individuals. Six polymorphic sites were non-synonymous SNPs, which were distributed in ND1, ND2, ATP6 and ND4 gene. Phylogenic analysis validated current taxa. The genome sequences of R. pulchra mitochondria could be comparable information for understanding species divergence and genomic variation among the populations.

Lactobacillus plantarum is a lactic acid bacterium that promotes animal intestinal health as a probiotic and is found in a wide variety of habitats. Here, we investigated the genomic features of different clusters of L. plantarum strains via pan-genomic analysis. We compared the genomes of 108 L. plantarum strains that were available from the NCBI GenBank database. These genomes were 2.9-3.7 Mbp in size and 44-45% in G+C content. A total of 8,847 orthologs were collected, and 1,709 genes were identified to be shared as core genes by all the strains analyzed. On the basis of SNPs from the core genes, 108 strains were clustered into five major groups (G1-G5) that are different from previous reports and are not clearly associated with habitats. Analysis of group-specific enriched or depleted genes revealed that G1 and G2 were rich in genes for carbohydrate utilization (L-arabinose, L-rhamnose, and fructooligosaccharides) and that G3, G4, and G5 possessed more genes for the restriction-modification system and MazEF toxin-antitoxin. These results indicate that there are critical differences in gene content and survival strategies among genetically clustered L. plantarum strains, regardless of habitats.

The gut microbiota in chicken has long been studied, mostly from the perspective of growth performance. However, there are some immunological studies regarding gut homeostasis in chicken. Although CD4+CD25+ T cells are reported to act as regulatory T cells (Tregs) in chicken, there have been no studies showing the relationship between gut microbiota and Tregs. Therefore, we established a model for ‘antibiotics (ABX)-treated chickens’ through administration of an antibiotic cocktail consisting of ampicillin, gentamycin, neomycin, metronidazole, and vancomycin in water for 7 days. CD4+CD8−CD25+ and CD4+CD8+CD25+ T cells in cecal tonsils were significantly decreased in this model. Gram-positive bacteria, especially Clostridia, was responsible for the changes in CD4+CD8−CD25+ or CD4+CD8+CD25+ T cells in cecal tonsils. Feeding ABX-treated chickens with acetate recovered CD4+CD8−CD25+ and CD4+CD8+CD25+ T cells in cecal tonsils. GPR43, a receptor for acetate, was highly expressed in CD4+CD8−CD25+ T cells. In conclusion, our study demonstrated that the gut microbiota can regulate the population of CD4+CD8−CD25+ and CD4+CD8+CD25+ T cells, and that acetate is responsible for the induction of CD4+CD8−CD25+ T cells in cecal tonsils via GPR43.

The gut microbiota in chicken has long been studied, mostly from the perspective of growth performance. However, there are some immunological studies regarding gut homeostasis in chicken. Although CD4

Age-associated molecular changes are deleterious and causally linked with aging and may affect life span through diet., Transition through life span is accompanied by numerous molecular changes, such as dysregulated gene expression, altered metabolite levels, and accumulated molecular damage. These changes are thought to be causal factors in aging; however, because they are numerous and are also influenced by genotype, environment, and other factors in addition to age, it is difficult to characterize the cumulative effect of these molecular changes on longevity. We reasoned that age-associated changes, such as molecular damage and tissue composition, may influence life span when used in the diet of organisms that are closely related to those that serve as a dietary source. To test this possibility, we used species-specific culture media and diets that incorporated molecular extracts of young and old organisms and compared the influence of these diets on the life span of yeast, fruitflies, and mice. In each case, the “old” diet or medium shortened the life span for one or both sexes. These findings suggest that age-associated molecular changes, such as cumulative damage and altered dietary composition, are deleterious and causally linked with aging and may affect life span through diet.

After the introduction of a ban on the use of antibiotic growth promoters (AGPs) for livestock, the feeding environment, including the composition of animal intestinal microbiota, has changed rapidly. We hypothesized that the microbial genomes have also been affected by this legal prohibition, and investigated an important member of the swine gut microbiota, Lactobacillus salivarius, with a pan-genomic approach. Here, we isolated 21 L. salivarius strains composed of 6 strains isolated before the AGP prohibition (SBPs) and 15 strains isolated after the AGP prohibition (SAPs) at an interval of a decade, and the draft genomes were generated de novo. Several genomic differences between SBPs and SAPs were identified, although the number and function of antibiotic resistance genes were not different. SBPs showed larger genome size and a higher number of orthologs, as well as lower genetic diversity, than SAPs. SBPs had genes associated with the utilization of L-rhamnose and D-tagatose for energy production. Because these sugars are also used in exopolysaccharide (EPS) synthesis, we tried to identify differences in biofilm formation-associated genes. The genes for the production of EPSs and extracellular proteins were different in terms of amino acid sequences. Indeed, SAPs formed dense biofilm and survived better than SBPs in the swine intestinal environment. These results suggest that SAPs have evolved and adapted to protect themselves from new selection pressure of the swine intestinal microenvironment by forming dense biofilms, adopting a distinct antibiotic resistance strategy. This finding is particularly important to understand the evolutionary changes in host-microbe interaction and provide detailed insight for the development of effective probiotics for livestock.

Mitochondrial genomes were sequenced from five Raja pulchra individuals, and single-nucleotide polymorphisms (SNPs) were identified by comparing previously announced sequences in this study. Total 117 SNPs were detected and they were present in 2 rRNA genes, 9 tRNA genes, 13 protein coding genes and non-coding region. One deleted polymorphic site, which was located in 16S rRNA gene, was observed in two individuals. Six polymorphic sites were non-synonymous SNPs, which were distributed in ND1, ND2, ATP6 and ND4 gene. Phylogenic analysis validated current taxa. The genome sequences of R. pulchra mitochondria could be comparable information for understanding species divergence and genomic variation among the populations.

Herein we report a draft genome sequence for Lactobacillus plantarum SNU.Lp177, which was isolated from animal gut pig feces in South Korea. The draft genome of L. plantarum SNU.Lp177 contains 3,204,772 bp with a G+C content of 44.98% in 101 contigs ( N 50 = 116,595 bp).

Complete mitochondria genome sequences of myotis petax (Chiroptera; Microchiroptera; Vespertilionidae) were first identified in the present study. The sequences were obtained from the four individuals and composition of nucleotide AT and GC was about 64.58% and 35.42%, respectively. The lengths of mitogenomes were ranged from 17 296 to 17 299 bp. Total 51 variable sites were observed in the four mitogenomes and 38 sites were singleton polymorphic sites. Phylogenic study revealed that the species would have relatively closed evolutionary distance with m. macrodactylus rather than other species in the genus, myotis. Present study will provide important genomic materials supporting confirmation of taxon of species called bats, which is included in one of the largest orders among the mammals.

Certain strains of Enterococcus faecium contribute beneficially to human health and food fermentation. However, other E. faecium strains are opportunistic pathogens due to the acquisition of virulence factors and antibiotic resistance determinants. To characterize E. faecium from soybean fermentation, we sequenced the genomes of 10 E. faecium strains from Korean soybean-fermented foods and analyzed their genomes by comparing them with 51 clinical and 52 non-clinical strains of different origins. Hierarchical clustering based on 13,820 orthologous genes from all E. faecium genomes showed that the 10 strains are distinguished from most of the clinical strains. Like non-clinical strains, their genomes are significantly smaller than clinical strains due to fewer accessory genes associated with antibiotic resistance, virulence, and mobile genetic elements. Moreover, we identified niche-associated gene gain and loss from the soybean strains. Thus, we conclude that soybean E. faecium strains might have evolved to have distinctive genomic features that may contribute to its ability to thrive during soybean fermentation.