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Environmental factors can influence the composition of gut microbiota, but understanding the combined effect of lifestyle factors on adult gut microbiota is limited. Here, we investigated whether changes in the modifiable lifestyle factors, such as cigarette smoking, alcohol consumption, sleep duration, physical exercise, and body mass index affected the gut microbiota of Korean navy trainees. The navy trainees were instructed to stop smoking and alcohol consumption and follow a sleep schedule and physical exercise regime for eight weeks. For comparison, healthy Korean civilians, who had no significant change in lifestyles for eight weeks were included in this study. A total of 208 fecal samples were collected from navy trainees (n = 66) and civilians (n = 38) at baseline and week eight. Gut flora was assessed by sequencing the highly variable region of the 16S rRNA gene. The &alpha, and &beta, diversity of gut flora of both the test and control groups were not significantly changed after eight weeks. However, there was a significant difference among individuals. Smoking had a significant impact in altering &alpha, diversity. Our study showed that a healthy lifestyle, particularly cessation of smoking, even in short periods, can affect the gut microbiome by enhancing the abundance of beneficial taxa and reducing that of harmful taxa.

Many bacteria found in the rhizosphere provide contribution for the host plant’s growth and protection that are known as plant growth-promoting rhizobacteria (PGPR). Plant–microbe interactions in the rhizosphere are important factors in determining the health of plants. Research for commercialization of these PGPR as an alternative to the use of chemical fertilizers for a more environmentally friendly treatment is continuously being improved. In this review, we discuss the essential traits that rhizobacteria must possess for them to be considered PGPR and report the bacterial species that exhibit these essential plant growth-promoting activities and which are approved for use by the South Korean regulations.

The enzyme xylose isomerase (E.C. 5.3.1.5, XI) is responsible for the conversion of an aldose to ketose, especially xylose to xylulose. Owing to the ability of XI to isomerize glucose to fructose, this enzyme is used in the food industry to prepare high-fructose corn syrup. Therefore, we studied the characteristics of XI from Anoxybacillus kamchatkensis G10, a thermophilic bacterium. First, the gene coding for XI (xylA) was inserted into the pET-21a(+) expression vector and the construct was transformed into the Escherichia coli competent cell BL21 (DE3). The expression of recombinant XI was induced in the absence of isopropyl-thio-β-galactopyranoside and purified using Ni-NTA affinity chromatography. The optimum temperature of recombinant XI was 80°C and measurement of the heat stability indicated that 55% of residual activity was maintained after 2 h incubation at 60°C. The optimum pH was found to be 7.5 in sodium phosphate buffer. Magnesium, manganese, and cobalt ions were found to increase the enzyme activity; manganese was the most effective. Additionally, recombinant XI was resistant to the presence of Ca²⁺ and Zn²⁺ ions. The kinetic properties, Km and Vmax, were calculated as 81.44 mM and 2.237 μmol/min/mg, respectively. Through redundancy analysis, XI of A. kamchatkensis G10 was classified into a family containing type II XIs produced by the genera Geobacillus, Bacillus, and Thermotoga. These results suggested that the thermostable nature of XI of A. kamchatkensis G10 may be advantageous in industrial applications and food processing.

Paenibacillus donghaensis JH8T (KCTC 13049T=LMG 23780T) is a Gram-positive, mesophilic, endospore-forming bacterium isolated from East Sea sediment at depth of 500m in Korea. The strain exhibited plant cell wall hydrolytic and plant growth promoting abilities. The complete genome of P. donghaensis strain JH8T contains 7602 protein-coding sequences and an average GC content of 49.7% in its chromosome (8.54Mbp). Genes encoding proteins related to the degradation of plant cell wall, nitrogen-fixation, phosphate solubilization, and synthesis of siderophore were existed in the P. donghaensis strain JH8T genome, indicating that this strain can be used as an eco-friendly microbial agent for increasing agricultural productivity.

A microbial imbalance called dysbiosis leads to inflammatory bowel disease (IBD), which can include ulcerative colitis (UC). Fecal microbiota transplantation (FMT), a novel therapy, has recently been successful in treating gut dysbiosis in UC patients. For the FMT technique to be successful, the gut microbiota of both the healthy donors and UC patients must be characterized. For decades, next-generation sequencing (NGS) has been used to analyze gut microbiota. Despite the popularity of NGS, the cost and time constraints make it difficult to use in emergency services and activities related to the periodic monitoring of microbiota profile alterations. Hence, in this study, we developed a multiplex TaqMan qPCR assay (MTq-PCR) with novel probes to simultaneously determine the relative proportions of the three dominant microbial phyla in the human gut: Bacteroidetes, Firmicutes, and Proteobacteria. The relative proportions of the three phyla in fecal samples of either healthy volunteers or UC patients were similar when assessed NGS and the MTq-PCR. Thus, our MTq-PCR assay could be a practical microbiota profiling alternative for diagnosing and monitoring gut dysbiosis in UC patients during emergency situations, and it could have a role in screening stool from potential FMT donors.

The great spotted woodpecker Dendrocopos major (Aves, Piciformes, Picidae) are the widespread woodpeckers from Eurasia and Northern Africa. The complete mitochondrial genome sequence consisted of 1...

The Indian scops owl Otus bakkamoena (Aves, Strigiformes, Strigidae) is a small resident owl in southern Asia. The complete mitochondrial genome sequence consisted of 17,389 base pairs (bp) encodin...

The Eurasian scops owl Otus scops (Aves, Strigiformes, Strigidae) is small typical owl belonging to the family Strigidae. The complete mitochondrial genome sequence consisted of 17413 base pairs en...

Macrophthalmus japonicus is located in the Macrophthalmidae family, but genetic research about the whole mitochondrial genome in Macrophthalmidae family doesn’t exist. Here, we report the first com...

Pyrhila pisum is known as leucosiid crab. So far, there is no study about whole mitochondrial genome in Leucosiidae family. Here, we report first the complete sequence of the mitochondrial genome from P. pisum, which is composed of 15,516 base pair encoding 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and A + T-rich region. The nucleotide composition of P. pisum was G + C: 25.5%, A + T: 74.5%, with a strong AT bias. In phylogenetic analysis using whole mitogenome, it was figured out that P. pisum was closely related to Sesarma neglectum but their family is different.

The larva of Galleria mellonella is widely used as a model organism for in vivo toxicology and pathogenicity testing. Here, we report complete sequence of the mitochondrial genome (mitogenome) from G. mellonella, which is comprised of 15,320 base pairs encoding 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and an A + T rich region. The overall base composition was G + C: 19.6%, A + T: 80.4%, with an apparent AT bias. Phylogenetic analysis using whole mitogenome revealed that G. mellonella was closely related to Corcyra cephalonica, which is in the same Pyralidae family.