Aged related human skin microbiome and mycobiome in Korean women.

We examined differences in the skin microbiome of two separate age groups to find key microbial and skin physiological indicators associated with aging. We recruited healthy Korean women 19-28 years old (Y-group) and 60-63 years old (O-group) and evaluated their cheek and forehead skin microbiome, including bacteria and fungi. The microbiome was significantly different by age group, with bacterial and fungal communities displaying higher alpha-diversity in the O-group than in the Y-group. We identified amplicon sequence variants affiliated with Cutibacterium and Lactobacillus and fungi Malassezia restricta as microbial biomarkers showing significant differences between the Y and O-group. There are more microbial communities and metabolic processes related to skin health in the Y-group than in the O-group, and there are more microbial interactions to increase the stability of the network structure of the skin. Skin physical metadata, including transepidermal water loss and sebum content, differed by two age groups. The crucial skin microbes, skin physical parameters, and microbial network found through this research will be useful key indicators in associating skin aging and skin microbiome research.

Changes in Fecal Pellet Microbiome of the Cold-Adapted Antarctic Copepod Tigriopus kingsejongensis at Different Temperatures and Developmental Stages.

Tigriopus kingsejongensis, a copepod species reported from the King Sejong Station, Antarctica, serves as a valuable food resource in ecosystems. We cultured T. kingsejongensis at three different temperatures (2 °C, 8 °C, and 15 °C) in a laboratory to observe the changes in its fecal pellet microbiome depending on the cultivation temperatures and developmental stages. We observed that the fecal pellet microbiome of the copepod changed with temperature: a lower microbial diversity, higher abundance of the aquatic bacterium Vibrio, and lower abundance of the psychrophilic bacterium Colwellia were noted at higher temperatures. In addition, the fecal pellet microbiome of the copepod changed according to the developmental stage: a lower microbial diversity was noted in egg-attached copepods than in nauplii at 8 °C. We further analyzed three shotgun metagenomes from the fecal pellet samples of T. kingsejongensis at different temperatures and obtained 44 metagenome-assembled genomes (MAGs). We noted that MAGs of V. splendidus D contained glycosyl hydrolases (GHs) encoding chitinases and virulence factors at a higher relative abundance at 15 °C than at lower temperatures. These results indicate that increasing temperature affects the fecal pellet microbiome and the development of copepods. The findings are helpful to understand the changes in cold-adapted copepods and the effect of temperature on their growth.

Antarctic tundra soil metagenome as useful natural resources of cold-active lignocelluolytic enzymes.

Lignocellulose composed of complex carbohydrates and aromatic heteropolymers is one of the principal materials for the production of renewable biofuels. Lignocellulose-degrading genes from cold-adapted bacteria have a potential to increase the productivity of biological treatment of lignocellulose biomass by providing a broad range of treatment temperatures. Antarctic soil metagenomes allow to access novel genes encoding for the cold-active lignocellulose-degrading enzymes, for biotechnological and industrial applications. Here, we investigated the metagenome targeting cold-adapted microbes in Antarctic organic matter-rich soil (KS 2-1) to mine lignolytic and celluloytic enzymes by performing single molecule, real-time metagenomic (SMRT) sequencing. In the assembled Antarctic metagenomic contigs with relative long reads, we found that 162 (1.42%) of total 11,436 genes were annotated as carbohydrate-active enzymes (CAZy). Actinobacteria, the dominant phylum in this soil's metagenome, possessed most of candidates of lignocellulose catabolic genes like glycoside hydrolase families (GH13, GH26, and GH5) and auxiliary activity families (AA7 and AA3). The predicted lignocellulose degradation pathways in Antarctic soil metagenome showed synergistic role of various CAZyme harboring bacterial genera including Streptomyces, Streptosporangium, and Amycolatopsis. From phylogenetic relationships with cellular and environmental enzymes, several genes having potential for participating in overall lignocellulose degradation were also found. The results indicated the presence of lignocellulose-degrading bacteria in Antarctic tundra soil and the potential benefits of the lignocelluolytic enzymes as candidates for cold-active enzymes which will be used for the future biofuel-production industry.

Analysis of excreta bacterial community after forced molting in aged laying hens.

OBJECTIVE: As laying hens become aged, laying performance and egg quality are generally impaired. One of the practical methods to rejuvenate production and egg quality of aged laying hens with decreasing productivity is a forced molting. However, the changes in intestinal microbiota after forced molting of aged hens are not clearly known. The aim of the present study was to analyze the changes in excreta bacterial communities after forced molting of aged laying hens. METHODS: A total of one hundred 66-wk-old Hy-Line Brown laying hens were induced to molt by a 2-d water removal and an 11-d fasting until egg production completely ceased. The excreta samples of 16 hens with similar body weight were collected before and immediately after molting. Excreta bacterial communities were analyzed by high-throughput sequencing of bacterial 16S rRNA genes. RESULTS: Bacteroidetes, Firmicutes, and Proteobacteria were the three major bacterial phyla in pre-molting and immediate post-molting hens, accounting for more than 98.0%. Lactobacillus genus had relatively high abundance in both group, but decreased by molting (62.3% in pre-molting and 24.9% in post-molting hens). Moreover, pathogenic bacteria such as Enterococcus cecorum and Escherichia coli were more abundant in immediate post-molting hens than in pre-molting hens. Forced molting influenced the alpha diversity, with higher Chao1 (p = 0.012), phylogenetic diversity whole tree (p = 0.014), observed operational taxonomic unit indices (p = 0.006), and Simpson indices (p<0.001), which indicated that forced molting increased excreta bacterial richness of aged laying hens. CONCLUSION: This study improves the current knowledge of bacterial community alterations in the excreta by forced molting in aged laying hens, which can provide increasing opportunity to develop novel dietary and management skills for improving the gastrointestinal health of aged laying hens after molting.

Butyrate attenuated fat gain through gut microbiota modulation in db/db mice following dapagliflozin treatment.

We investigated the effect of a combination treatment with dapagliflozin (Dapa), a sodium-glucose cotransporter-2 inhibitor and butyrate on weight change in db/db mice. Six-week-old male db/db mice were assigned to four groups: vehicle with normal chow diet (NCD), Dapa with NCD, vehicle with 5% sodium butyrate-supplemented NCD (NaB), or Dapa with 5% NaB. After six weeks of treatment, faecal microbiota composition was analysed by sequencing 16S ribosomal RNA genes. In the vehicle with NaB and Dapa + NaB groups, body weight increase was attenuated, and amount of food intake decreased compared with the vehicle with the NCD group. The Dapa + NaB group gained the least total and abdominal fat from baseline. Intestinal microbiota of this group was characterized by a decrease of the Firmicutes to Bacteroidetes ratio, a decrease of Adlercreutzia and Alistipes, as well as an increase of Streptococcus. In addition, the proportion of Adlercreutzia and Alistipes showed a positive correlation with total fat gain, whereas Streptococcus showed a negative correlation. Inferred metagenome function revealed that tryptophan metabolism was upregulated by NaB treatment. We demonstrated a synergistic effect of Dapa and NaB treatment on adiposity reduction, and this phenomenon might be related to intestinal microbiota alteration.

Metagenomic SMRT Sequencing-Based Exploration of Novel Lignocellulose-Degrading Capability in Wood Detritus from Torreya nucifera in Bija Forest on Jeju Island.

Lignocellulose, composed mostly of cellulose, hemicellulose, and lignin generated through secondary growth of woody plant, is considered as promising resources for biofuel. In order to use lignocellulose as a biofuel, biodegradation besides high-cost chemical treatments were applied, but knowledge on the decomposition of lignocellulose occurring in a natural environment is insufficient. We analyzed the 16S rRNA gene and metagenome to understand how the lignocellulose is decomposed naturally in decayed Torreya nucifera (L) of Bija forest (Bijarim) in Gotjawal, an ecologically distinct environment. A total of 464,360 reads were obtained from 16S rRNA gene sequencing, representing diverse phyla; Proteobacteria (51%), Bacteroidetes (11%) and Actinobacteria (10%). The metagenome analysis using single molecules real-time sequencing revealed that the assembled contigs determined originated from Proteobacteria (58%) and Actinobacteria (10.3%). Carbohydrate Active enZYmes (CAZy)- and Protein families (Pfam)-based analysis showed that Proteobacteria was involved in degrading whole lignocellulose, and Actinobacteria played a role only in a part of hemicellulose degradation. Combining these results, it suggested that Proteobacteria and Actinobacteria had selective biodegradation potential for different lignocellulose substrates. Thus, it is considered that understanding of the systemic microbial degradation pathways may be a useful strategy for recycle of lignocellulosic biomass, and the microbial enzymes in Bija forest can be useful natural resources in industrial processes.