MSK
Search
- Page Path
- HOME > Search
Journal Articles
- Rasiella rasia gen. nov. sp. nov. within the family Flavobacteriaceae isolated from seawater recirculating aquaculture system
- Seong-Jin Kim , Young-Sam Kim , Sang-Eon Kim , Hyun-Kyoung Jung , Jeeeun Park , Min-Ju Yu , Kyoung-Ho Kim
- J. Microbiol. 2022;60(11):1070-1076. Published online October 17, 2022
- DOI: https://doi.org/10.1007/s12275-022-2099-7
- 17 View
- 0 Download
- 1 Citations
-
Abstract
- A novel bacterium designated RR4-40T was isolated from a biofilter of seawater recirculating aquaculture system in Busan, South Korea. Cells are strictly aerobic, Gram-negative, irregular short rod, non-motile, and oxidase- and catalase-negative. Growth was observed at 15–30°C, 0.5–6% NaCl (w/v), and pH 5.0–9.5. The strain grew optimally at 28°C, 3% salinity (w/v), and pH 8.5. The phylogenetic analysis based on 16S rRNA gene sequences showed that strain RR4-40T was most closely related to Marinirhabdus gelatinilytica NH83T (94.16% of 16S rRNA gene similarity) and formed a cluster with genera within the family Flavobacteriaceae. The values of the average nucleotide identity (ANI), digital DNA-DNA hybridization (dDDH), and average amino acid identity (AAI) between genomes of strain RR4-40T and M. gelatinilytica NH83T were 72.91, 18.2, and 76.84%, respectively, and the values against the strains in the other genera were lower than those. The major fatty acids were iso-C15:0 (31.34%), iso-C17:0 3-OH (13.65%), iso-C16:0 3-OH (10.61%), and iso-C15:1 G (10.38%). The polar lipids comprised phosphatidylglycerol, diphosphatidylglycerol, aminophospholipid, aminolipid, glycolipid, and sphingolipid. The major respiratory quinone was menaquinone-6 (MK-6) and the DNA G + C content of strain RR4-40T was 37.4 mol%. According to the polyphasic analysis, strain RR4-40T is considered to represent a novel genus within the family Flavobacteriaceae, for which the name Rasiella rasia gen. nov, sp. nov. is proposed. The type strain is RR4-40T (= KCTC 52650T = MCCC 1K04210T).
- Role of melatonin in murine “restraint stress”-induced dysfunction of colonic microbiota
- Rutao Lin , Zixu Wang , Jing Cao , Ting Gao , Yulan Dong , Yaoxing Chen
- J. Microbiol. 2021;59(5):500-512. Published online February 25, 2021
- DOI: https://doi.org/10.1007/s12275-021-0305-7
- 15 View
- 0 Download
- 12 Citations
-
Abstract
- Intestinal diseases caused by physiological stress have become a severe public health threat worldwide. Disturbances in the gut microbiota-host relationship have been associated with irritable bowel disease (IBD), while melatonin (MT) has antiinflammatory and antioxidant effects. The objective of this study was to investigate the mechanisms by which MT-mediated protection mitigated stress-induced intestinal microbiota dysbiosis and inflammation. We successfully established a murine restraint stress model with and without MT supplementation. Mice subjected to restraint stress had significantly elevated corticosterone (CORT) levels, decreased MT levels in their plasma, elevated colonic ROS levels and increased bacterial abundance, including Bacteroides and Tyzzerella, in their colon tract, which led to elevated expression of Toll-like receptor (TLR) 2/4, p-P65 and p-IκB. In contrast, supplementation with 20 mg/kg MT reversed the elevation of the plasma CORT levels, downregulated the colon ROS levels and inhibited the changes in the intestinal microbiota induced by restraint stress. These effects, in turn, inhibited the activities of TLR2 and TLR4, p-P65 and p-IκB, and decreased the inflammatory reaction induced by restraint stress. Our results suggested that MT may mitigate “restraint stress”-induced colonic microbiota dysbiosis and intestinal inflammation by inhibiting the activation of the NF-κB pathway.
First
Prev
TOP
