Tailed-Hoogsteen Triplex DNA Silver Nanoclusters Emit Red Fluorescence upon Target miRNA Sensing.

MicroRNAs (miRNAs) are small RNA molecules, typically 21‒22 nucleotides in size, which play a crucial role in regulating gene expression in most eukaryotes. Their significance in various biological processes and disease pathogenesis has led to considerable interest in their potential as biomarkers for diagnosis and therapeutic applications. In this study, a novel method for sensing target miRNAs using Tailed-Hoogsteen triplex DNA-encapsulated Silver Nanoclusters (DNA/AgNCs) is introduced. Upon hybridization of a miRNA with the tail, the Tailed-Hoogsteen triplex DNA/AgNCs exhibit a pronounced red fluorescence, effectively turning on the signal. It is successfully demonstrated that this miRNA sensor not only recognized target miRNAs in total RNA extracted from cells but also visualized target miRNAs when introduced into live cells, highlighting the advantages of the turn-on mechanism. Furthermore, through gel-fluorescence assays and small-angle X-ray scattering (SAXS) analysis, the turn-on mechanism is elucidated, revealing that the Tailed-Hoogsteen triplex DNA/AgNCs undergo a structural transition from a monomer to a dimer upon sensing the target miRNA. Overall, the findings suggest that Tailed-Hoogsteen triplex DNA/AgNCs hold great promise as practical sensors for small RNAs in both in vitro and cell imaging applications.

Energy Transfer Between i-Motif DNA Encapsulated Silver Nanoclusters and Fluorescein Amidite Efficiently Visualizes the Redox State of Live Cells.

The redox regulation, maintaining a balance between oxidation and reduction in living cells, is vital for cellular homeostasis, intricate signaling networks, and appropriate responses to physiological and environmental cues. Here, a novel redox sensor, based on DNA-encapsulated silver nanoclusters (DNA/AgNCs) and well-defined chemical fluorophores, effectively illustrating cellular redox states in live cells is introduced. Among various i-motif DNAs, the photophysical property of poly-cytosines (C20)-encapsulated AgNCs that sense reactive oxygen species (ROS) is adopted. However, the sensitivity of C20/AgNCs is insufficient for evaluating ROS levels in live cells. To overcome this drawback, the ROS sensing mechanism of C20/AgNCs through gel electrophoresis, mass spectrometry, and small-angle X-ray scattering is primarily defined. Then, by tethering fluorescein amidite (FAM) and Cyanine 5 (Cy5) dyes to each end of the C20/AgNCs sensor, an Energy Transfer (ET) between AgNCs and FAM is achieved, resulting in intensified green fluorescence upon ROS detection. Taken together, the FAM-C20/AgNCs-Cy5 redox sensor enables dynamic visualization of intracellular redox states, yielding insights into oxidative stress-related processes in live cells.

Guanidinium and amide CEST mapping of human brain by high spectral resolution CEST at 3 T.

PURPOSE: To extract guanidinium (Guan) and amide CEST on the human brain at 3 T MRI with the high spectral resolution (HSR) CEST combined with the polynomial Lorentzian line-shape fitting (PLOF). METHODS: Continuous wave (cw) turbo spin-echo (TSE) CEST was implemented to obtain the optimum saturation parameters. Both Guan and amide CEST peaks were extracted and quantified using the PLOF method. The NMR spectra on the egg white phantoms were acquired to reveal the fitting range and the contributions to the amide and GuanCEST. Two types of CEST approaches, including cw gradient- and spin-echo (cwGRASE) and steady state EPI (ssEPI), were implemented to acquire multi-slice HSR-CEST. RESULTS: GuanCEST can be extracted with the PLOF method at 3 T, and the optimum B 1 = 0.6 µ T $$ {\mathrm{B}}_1=0.6\kern0.2em \upmu \mathrm{T} $$ was determined for GuanCEST in white matter (WM) and 1.0 µT in gray matter (GM). The optimum B1  = 0.8-1 µT was found for amideCEST. AmideCEST is lower in both WM and GM collected with ssEPI compared to those by cwGRASE (ssEPI = [1.27-1.63]%; cwGRASE = [2.19-2.25]%). The coefficients of variation (COV) of the amide and Guan CEST in both WM and GM for ssEPI (COV: 28.6-33.4%) are significantly higher than those of cwGRASE (COV: 8.6-18.8%). Completely different WM/GM contrasts for Guan and amide CEST were observed between ssEPI and cwGRASE. The amideCEST was found to have originated from the unstructured amide protons as suggested by the NMR spectrum of the unfolded proteins in egg white. CONCLUSION: Guan and amide CEST mapping can be achieved by the HSR-CEST at 3 T combing with the PLOF method.

The exchange rate of creatine CEST in mouse brain.

PURPOSE: To estimate the exchange rate of creatine (Cr) CEST and to evaluate the pH sensitivity of guanidinium (Guan) CEST in the mouse brain. METHODS: Polynomial and Lorentzian line-shape fitting (PLOF) were implemented to extract the amine, amide, and Guan CEST signals from the brain Z-spectrum at 11.7T. Wild-type (WT) and knockout mice with the guanidinoacetate N-methyltransferase deficiency (GAMT-/- ) that have low Cr and phosphocreatine (PCr) concentrations in the brain were used to extract the CrCEST signal. To quantify the CrCEST exchange rate, a two-step Bloch-McConnell (BM) fitting was used to fit the CrCEST line-shape, B1 -dependent CrCEST, and the pH response with different B1 values. The pH in the brain cells was altered by hypercapnia to measure the pH sensitivity of GuanCEST. RESULTS: Comparison between the Z-spectra of WT and GAMT-/- mice suggest that the CrCEST is between 20% and 25% of the GuanCEST in the Z-spectrum at 1.95 ppm between B1 = 0.8 and 2 µT. The CrCEST exchange rate was found to be around 240-480 s-1 in the mouse brain, which is significantly lower than that in solutions (∼1000 s-1 ). The hypercapnia study on the mouse brain revealed that CrCEST at B1 = 2 µT and amineCEST at B1 = 0.8 µT are highly sensitive to pH change in the WT mouse brain. CONCLUSIONS: The in vivo CrCEST exchange rate is slow, and the acquisition parameters for the CrCEST should be adjusted accordingly. CrCEST is the major contribution to the opposite pH-dependence of GuanCEST signal under different conditions of B1 in the brain.

Advanced low blaze angle x-ray gratings via nanoimprint replication and plasma etch.

We developed a new method of making ultra-low blaze angle diffraction gratings for x-ray applications. The method is based on reduction of the blaze angle of a master grating by nanoimprint replication followed by a plasma etch. A master blazed grating with a relatively large blaze angle is fabricated by anisotropic wet etching of a Si single crystal substrate. The surface of the master grating is replicated by a polymer material on top of a quartz substrate by nanoimprinting. Then a second nanoimprinting is performed using the 1st replica as a mold to replicate the saw-tooth surface into a resist layer on top of a Si grating substrate. A reactive ion etch is used to transfer the grating grooves into the Si substrate. The plasma etch provides reduction of the groove depth by a factor defined by the ratio of the etch rates for the resist and Si. We demonstrate reduction of the blaze angle of a master grating by a factor of 5 during fabrication of a 200 lines/mm blazed grating with a blaze angle of 0.2°. We investigated the quality and performance of the fabricated low blaze angle gratings and evaluate process accuracy and reproducibility. The new blaze angle reduction method preserves the planarity of the optical surface of the grating substrate and at the same time provides improvement in the grating groove quality during the reduction process.

Roseobacter insulae sp. nov. and Loktanella gaetbuli sp. nov., isolated from tidal flats in the Yellow Sea in Korea.

Two bacterial strains (designated as YSTF-M11T and TSTF-M6T) were isolated from tidal flat sediments of the Yellow Sea, Republic of Korea, and taxonomically characterized. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain YSTF-M11T clusters with the type strains of Roseobacter species and strain TSTF-M6T clusters with the type strains of Loktanella salsilacus, Loktanella fryxellensis and Loktanella atrilutea. Strains YSTF-M11T and TSTF-M6T exhibited 16S rRNA gene sequence similarity values of 97.5-98.9 % and 94.1-97.2 % to the type strains of four Roseobacter species and to the type strains of four Loktanella species, respectively. An UBCG tree based on genomic sequences and a tree based on AAI showed that strains YSTF-M11T and TSTF-M6T form a cluster with the type strains of Roseobacter species and with the type strains of L. salsilacus, L. fryxellensis and L. atrilutea, respectively. The ANI and dDDH values between genomic sequences of strain YSTF-M11T and the type strains of four Roseobacter species and between those of strain TSTF-M6T and the type strains of the three Loktanella species were in ranges of 74.0-75.9 and 18.2-19.7 % and 74.7-75.5 and 18.8-19.3 %, respectively. The DNA G+C contents of strains YSTF-M11T and TSTF-M6T were 60.3 and 61.9 % based on their genomic sequences. Both strains contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c as the major fatty acid. Strains YSTF-M11T and TSTF-M6T were separated from recognized Roseobacter species and L. salsilacus, L. fryxellensis and L. atrilutea, respectively, by their phenotypic properties together with the phylogenetic and genetic distinctiveness. Based on data presented in this study, strains YSTF-M11T (=KACC 21642T =NBRC 115155T) and TSTF-M6T (=KACC 21643T =NBRC 115154T) are considered to represent novel species of the genera Roseobacter and Loktanella, respectively, for which the names Roseobacter insulae sp. nov. and Loktanella gaetbuli sp. nov. are proposed.

Tianweitania aestuarii sp. nov., isolated from a coastal dune, reclassification of Corticibacterium populi as Tianweitania populi comb. nov., and emended description of the genus Tianweitania.

A Gram-stain-negative, aerobic, non-flagellated and coccoid or ovoid bacterial strain, BSSL-BM11T, was isolated from sand of coastal dunes along the Yellow Sea of the Korean peninsula. Strain BSSL-BM11T grew optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2.0-3.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences, the up-to-date bacterial core gene set and average amino acid identity (AAI) showed that strain BSSL-BM11T forms a cluster with the type strains of Tianweitania sediminis and Corticibacterium populi. Strain BSSL-BM11T showed 16S rRNA gene sequence similarities of 98.3 and 98.0 % to the type strains of T. sediminis and C. populi, respectively, and less than 96.4 % to the type strains of the other recognized species. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain BSSL-BM11T and the type strains of T. sediminis and C. populi were 77.0-84.8 % and 20.0-28.1 %, respectively. The 16S rRNA gene similarity, AAI, ANI and dDDH values between T. sediminis Z8T and C. populi KCTC 42249T were 98.0, 77.4, 76.7 and 20.1 %, respectively. The DNA G+C content of strain BSSL-BM11T from genomic sequence data was 61.3 mol%. Strain BSSL-BM11T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c, C16 : 0 and cyclo C19 : 0 ω8c as the major fatty acids. The major polar lipids of strain BSSL-BM11T were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. Based on the polyphasic data, it is proposed that C, populi be reclassified as a member of the genus Tianweitania. Phenotypic and phylogenetic analyses revealed that strain BSSL-BM11T is separated from T. sediminis and C. populi. On the basis of the data presented here, strain BSSL-BM11T (=KACC 21634T=NBRC 114503T) is considered to represent a novel species of the genus Tianweitania, for which the name Tianweitania aestuarii sp. nov. is proposed.

Exploring the Effect of Deep-Sea Water on the Therapeutic Potential of the Anti-Inflammatory Response in an Indomethacin-Induced Gastric Ulcer Rat Model.

Gastric ulcers are often exacerbated by factors such as nonsteroidal anti-inflammatory drugs (NSAIDs) and inflammation, and they have a substantial impact on a significant portion of the population. Notably, indomethacin is recognized as a prominent contributor to ulcers. This study investigated this potential method, with normalization to the anti-inflammatory and antiulcer properties of deep-sea water (DSW)-derived mineral water, using an indomethacin-induced gastric ulcer model in rats. The study involved four groups (n = 6 rats/group): normal control group (CON), indomethacin-only group (IND), indomethacin with trace mineral water group (TM), and indomethacin with high magnesium low sodium water group (HMLS). For three weeks, the CON and IND groups consumed tap water, while the TM and HMLS groups had access to mineral water. Gastric ulcers were induced on the final day using indomethacin, for all groups except the CON group. The results demonstrated that HMLS intake significantly improved gastric mucosal damage, preserved mucin stability, and increased gastric thickness, indicating its potential to prevent and alleviate indomethacin-induced gastric ulcers. Furthermore, HMLS consumption led to the upregulation of key genes associated with inflammation and a reduction in inflammatory cytokines. These findings suggest that DSW-derived mineral water, and particularly its high Mg2+ content, may offer promising health benefits including anti-inflammatory and anti-ulcer properties.

Devosia litorisediminis sp. nov., isolated from a sand dune.

A Gram-negative, aerobic, non-motile, and rod-shaped bacterial strain, designated BSSL-BM10T, was isolated from sand of a dune that was collected from the Yellow Sea, Republic of Korea. It was subjected to a polyphasic taxonomic study. 16S rRNA gene sequence analysis showed that strain BSSL-BM10T fell phylogenetically within the radiation comprising type strains of Devosia species. The 16S rRNA gene sequence of strain BSSL-BM10T shared sequence similarities of 98.2% with the type strain of D. naphthalenivorans and 93.5-97.7% with type strains of other Devosia species. ANI and dDDH values between strain BSSL-BM10T and type strains of 18 Devosia species were 71.0-78.4% and 18.8-21.5%, respectively. The DNA G + C content of strain BSSL-BM10T was 60.9% based on its genomic sequence data. Strain BSSL-BM10T contained Q-10 as the predominant ubiquinone and 11-methyl C18:1 ω7c, C18:1 ω7c, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), and C16:0 as its major fatty acids. Major polar lipids of strain BSSL-BM10T were phosphatidylglycerol and two unidentified glycolipids. Strain BSSL-BM10T showed distinguishable phenotypic properties with its phylogenetic and genetic distinctiveness separated from recognized Devosia species. Based on data presented in this study, strain BSSL-BM10T should be placed in the genus Devosia. The name Devosia litorisediminis sp. nov. is proposed for strain BSSL-BM10T (= KACC 21633T = NBRC 115152T).

Mesonia aestuariivivens sp. nov., isolated from a tidal flat.

A Gram-negative, aerobic, non-flagellated and ovoid or rod-shaped bacterial strain (JHPTF-M18T), which was isolated from a tidal flat sediment in Republic of Korea, was taxonomically characterized. Strain JHPTF-M18T grew optimally at 25 °C, at pH 7.0-7.5 and in the presence of 2.0-3.0% (w/v) NaCl. 16S rRNA gene sequence analysis showed that strain JHPTF-M18T forms a phylogenetic lineage within the radiation comprising type strains of Mesonia species. The 16S rRNA gene of strain JHPTF-M18T shared sequence similarities of 97.7% with that of type strain of M. mobilis and 92.5-96.8% with those of type strains of the other nine Mesonia species. The DNA G+C content was 33.1% based on its genomic sequence. AAI, ANI and dDDH values between strain JHPTF-M18T and the type strains of M. mobilis, M. hitae, M. oceanica, M. phycicola and M. algae were 72.1-83.7%, 73.1-79.7% and 18.5-22.8%, respectively. Strain JHPTF-M18T contained MK-6 as the predominant menaquinone and iso-C15:0, iso-C17:0 3-OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) as its major fatty acids. Major polar lipids of strain JHPTF-M18T were phosphatidylethanolamine and two unidentified lipids. Strain JHPTF-M18T was separated from recognized Mesonia species by its phenotypic properties together with the phylogenetic and genetic distinctiveness. Based on data presented in this study, strain JHPTF-M18T is considered to represent a novel species of the genus Mesonia. The name Mesonia aestuariivivens sp. nov. is proposed for JHPTF-M18T (=KACC 22185T = NBRC 115119T).

Enterovibrio paralichthyis sp. nov., isolated from the gut of an olive flounder Paralichthys olivaceus.

A Gram-stain-negative, facultatively anaerobic, flagellated and coccoid, ovoid or rod-shaped bacterial strain, NIFS-20-8T, was isolated from the intestine of an olive flounder (Paralichthys olivaceus) from the East Sea, Republic of Korea. The neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain NIFS-20-8T fell within the clade comprising the type strains of Enterovibrio species. Strain NIFS-20-8T exhibited 16S rRNA gene sequence similarities of 97.2 and 97.1 % to the type strains of Enterovibrio nigricans and Enterovibrio norvegicus, respectively, and of 96.6-97.0 % to the type strains of the other Enterovibrio species. The average nucleotide identity and digital DNA-DNA hybridization values between the genomic sequence of strain NIFS-20-8T and those of the type strains of four Enterovibrio species were 73.8-75.0 and 19.8-21.1 %, respectively. The DNA G+C content of strain NIFS-20-8T from genomic sequence data was 50.55 mol%. Strain NIFS-20-8T contained Q-8 as the predominant ubiquinone and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C16 : 0 and C18 : 1 ω7c as the major fatty acids. The major polar lipids detected in stain NIFS-20-8T were phosphatidylethanolamine and phosphatidylglycerol. Distinguishing phenotypic properties, together with phylogenetic and genetic distinctiveness, revealed that strain NIFS-20-8T is separated from recognized Enterovibrio species. On the basis of the data presented here, strain NIFS-20-8T is considered to represent a novel species of the genus Enterovibrio, for which the name Enterovibrio paralichthyis sp. nov. is proposed. The type strain is NIFS-20-8T (= KCTC 82873T=NBRC 115237T).

Sulfitobacter aestuariivivens sp. nov., isolated from a tidal flat.

A Gram-stain-negative, aerobic, non-flagellated, coccoid, ovoid or rod-shaped bacterial strain, TSTF-M16T, was isolated from a tidal flat on the Yellow Sea, Republic of Korea. The neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain TSTF-M16T fell within a clade comprising the type strains of Sulfitobacter species. Strain TSTF-M16T exhibited 16S rRNA gene sequence similarities of 98.5 and 98.1 % to the type strains of Sulfitobacter mediterraneus and Sulfitobacter sabulilitoris, respectively, and 96.2-97.8 % to the type strains of the other Sulfitobacter species. The average nucleotide identity and digital DNA-DNA hybridization values between the genomic sequences of strain TSTF-M16T and the type strains of 16 Sulfitobacter species were 70.6-74.2 and 17.9-19.0 %, respectively. The DNA G+C content of strain TSTF-M16T from genomic sequence data was 59.26 mol%. Strain TSTF-M16T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c as the major fatty acid. The major polar lipids of strain TSTF-M16T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. Distinguished phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain TSTF-M16T is separated from recognized Sulfitobacter species. On the basis of the data presented here, strain TSTF-M16T is considered to represent a novel species of the genus Sulfitobacter, for which the name Sulfitobacter aestuariivivens sp. nov. is proposed. The type strain is TSTF-M16T (=KACC 21645T=NBRC 114501T).

Kordia aestuariivivens sp. nov. and Olleya sediminilitoris sp. nov., isolated from a tidal flat.

Two Gram-stain-negative and non-flagellated bacteria, YSTF-M3T and YSTF-M6T, were isolated from a tidal flat from Yellow Sea, Republic of Korea, and subjected to a polyphasic taxonomic study. Neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strains YSTF-M3T and YSTF-M6T belong to the genera Kordia and Olleya of the family Flavobacteriaceae, respectively. The 16S rRNA gene sequence similarities between strain YSTF-M3T and the type strains of Kordia species and between strain YSTF-M6T and the type strains of Olleya species were 94.1-98.4 and 97.3-98.3 %, respectively. The ANI and dDDH values between genomic sequences of strain YSTF-M3T and the type strains of five Kordia species and between those of strain YSTF-M6T and the type strains of three Olleya species were in ranges of 77.0-83.2 and 20.7-27.1 % and 79.4-81.5 and 22.3-23.9 %, respectively. The DNA G+C contents of strain YSTF-M3T and YSTF-M6T from genomic sequences were 34.1 and 31.1 %, respectively. Both strains contained MK-6 as predominant menaquinone and phosphatidylethanolamine as only major phospholipid identified. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strains YSTF-M3T and YSTF-M6T are separated from recognized species of the genera Kordia and Olleya, respectively. On the basis of the data presented, strains YSTF-M3T (=KACC 21639T=NBRC 114499T) and YSTF-M6T (=KACC 21640T=NBRC 114500T) are considered to represent novel species of the genera Kordia and Olleya, respectively, for which the names Kordia aestuariivivens sp. nov. and Olleya sediminilitoris sp. nov. are proposed.

Paenihalocynthiibacter styelae gen. nov., sp. nov., isolated from stalked sea squirt Styela clava.

A Gram-stain-negative, strictly aerobic, non-motile and rod-shaped bacterial strain, MYP1-1T, was isolated from the intestine of a stalked sea squirt (Styela clava) of the South Sea in the Republic of Korea. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain MYP1-1T clustered with the type strains of Halocynthiibacter species and Pseudohalocynthiibacter aestuariivivens. Strain MYP1-1T exhibited 16S rRNA gene sequence similarity values of 97.0-97.6 % to the type strains of Halocynthiibacter namhaensis, Halocynthiibacter arcticus and P. aestuariivivens. The phylogenetic tree based on genomic sequences showed that strain MYP1-1T formed a distinct branch separating it from the type strains of two Halocynthiibacter species and P. aestuariivivens and other taxa. The DNA G+C content of strain MYP1-1T from its genomic sequence was 55.0 mol%. Strain MYP1-1T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c as the major fatty acid. The major polar lipids of strain MYP1-1T were phosphatidylcholine, phosphatidylglycerol, one unidentified lipid and one unidentified aminolipid. The differences in fatty acid and polar lipid profiles and other differential phenotypic properties made it reasonable to distinguish strain MYP1-1T from the genera Halocynthiibacter and Pseudohalocynthiibacter. On the basis of the polyphasic taxonomic investigations, we conclude that strain MYP1-1T constitutes a new genus and species within the class Alphaproteobacteria, for which the name Paenihalocynthiibacter styelae gen. nov., sp. nov. is proposed. The type strain is MYP1-1T (=KCTC 82143T=NBRC 114355T).

Programmed cell death 5 suppresses AKT-mediated cytoprotection of endothelium.

Programmed cell death 5 (PDCD5) has been associated with human cancers as a regulator of cell death; however, the role of PDCD5 in the endothelium has not been revealed. Thus, we investigated whether PDCD5 regulates protein kinase B (PKB/AKT)-endothelial nitric oxide synthase (eNOS)-dependent signal transduction in the endothelium and affects atherosclerosis. Endothelial-specific PDCD5 knockout mice showed significantly reduced vascular remodeling compared with wild-type (WT) mice after partial carotid ligation. WT PDCD5 competitively inhibited interaction between histone deacetylase 3 (HDAC3) and AKT, but PDCD5L6R, an HDAC3-binding-deficient mutant, did not. Knockdown of PDCD5 accelerated HDAC3-AKT interaction, AKT and eNOS phosphorylation, and nitric oxide (NO) production in human umbilical vein endothelial cells. Moreover, we found that serum PDCD5 levels reflect endothelial NO production and are correlated with diabetes mellitus, high-density lipoprotein cholesterol, and coronary calcium in human samples obtained from the cardiovascular high-risk cohort. Therefore, we conclude that PDCD5 is associated with endothelial dysfunction and may be a novel therapeutic target in atherosclerosis.

Effect of Mineral-Balanced Deep-Sea Water on Kidney Function and Renal Oxidative Stress Markers in Rats Fed a High-Salt Diet.

This study investigated the effect of mineral-balanced deep-sea water (DSW) on kidney health using an animal model of kidney injury due to a high-sodium diet. High magnesium/low sodium (HMLS) and high magnesium/high calcium (HMHC) DSW samples with different mineral contents were prepared. Sprague-Dawley rats were fed an 8% sodium chloride (NaCl) diet for four weeks to induce kidney injury, and each group was supplied with purified water or mineral water. Kidney injury was observed in the NaCl group according to increased kidney injury markers and malondialdehydes, providing evidence of oxidative stress. However, the kidney injury was repaired by the intake of mineral-balanced DSW. It was confirmed that the HMLS and HMHC groups showed improved Na+ excretion through the urine. Kidney injury markers in urine decreased and upregulation of low-density lipoprotein receptor-related protein2 mRNA expression was observed in the HMLS and HMHC groups. In addition, superoxide dismutase activity was increased in the HMHC groups. The gene expression patterns of the RNA sequencing were similar between the CON and HMLS groups. These results suggest that DSW has beneficial effects on kidney health due to the balanced magnesium and calcium levels in models of kidney injury caused by excessive sodium intake.

Erythrobacter insulae sp. nov., isolated from a tidal flat.

A Gram-staining-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated as JBTF-M21T, was isolated from a tidal flat sediment on the Yellow Sea, Republic of Korea. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences indicated that JBTF-M21T fell within the clade comprising the type strains of species of the genus Erythrobacter. JBTF-M21T exhibited 16S rRNA gene sequence similarities of 97.0-98.4 % to the type strains of Erythrobacter longus, Erythrobacter aquimaris, Erythrobacter nanhaisediminis, Erythrobacter vulgaris, Erythrobacter seohaensis, Erythrobacter litoralis and Erythrobacter citreus and 93.7-96.6 % to the type strains of the other species of the genus Erythrobacter. The ANI and dDDH values between JBTF-M21T and the type strains of E. longus, E. nanhaisediminis, E. seohaensis and E. litoralis were 70.83-72.93 % and 18.0-18.8 %, respectively. Mean DNA-DNA relatedness values between JBTF-M21T and the type strains of E. aquimaris, E. vulgaris and E. citreus were 12-24 %. The DNA G+C content of JBTF-M21T was 57.0 mol%. JBTF-M21T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and C17 : 1ω6c as the major fatty acids. The major polar lipids ofJBTF-M21T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid. Distinguishing phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that JBTF-M21T is separated from species of the genus Erythrobacter with validly published names. On the basis of the data presented, strain JBTF-M21T is considered to represent a novel species of the genus Erythrobacter, for which the name Erythrobacter insulae sp. nov. is proposed. The type strain is JBTF-M21T (=KACC 19864T=NBRC 113584T).

Alteromonas ponticola sp. nov., a gammaproteobacterium isolated from seawater.

A Gram-stain-negative, aerobic, non-spore-forming, non-motile and ovoid or rod-shaped bacterial strain, MYP5T, was isolated from seawater in Jeju island of South Korea. MYP5T grew optimally at 30-35 °C and in the presence of 2.0 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that MYP5T fell within the clade enclosed by the type strains of species of the genus Alteromonas, clustering with the type strains of Alteromonas confluentis and Alteromonas halophila. MYP5T exhibited the highest 16S rRNA gene sequence similarity value (98.0 %) to the type strain of A. confluentis and similarities of 95.1-97.9 % to the type strains of the other species of the genus Alteromonas. ANI and dDDH values of genomic sequences between MYP5T and the type strains of 22 species of the genus Alteromonas were 66.8-70.5 % and 18.6-27.5 %, respectively. The DNA G+C content of MYP5T, determined from the genome sequence, was 46.1 %. MYP5T contained Q-8 as the predominant ubiquinone and C18 : 1 ω7c, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C16 : 0 and 10-methyl C17 : 0 as the major fatty acids. The major polar lipids of MYP5T were phosphatidylethanolamine and phosphatidylglycerol. Distinguishing phenotypic properties, along with the phylogenetic and genetic distinctiveness, revealed that MYP5T is separated from species of the genus Alteromonas. On the basis of the data presented, MYP5T is considered to represent a novel species of the genus Alteromonas, for which the name Alteromonas ponticola sp. nov. is proposed. The type strain is MYP5T (=KCTC 82144T=NBRC 114354T).

Pseudoalteromonas caenipelagi sp. nov., isolated from a tidal flat.

A Gram-stain-negative, aerobic, non-spore-forming, motile by single polar flagellum and ovoid or rod-shaped bacterial strain, designated JBTF-M23T, was isolated from tidal flat sediment collected from the Yellow Sea, Republic of Korea. Neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain JBTF-M23T fell within the clade comprising the type strains of Pseudoalteromonas species, clustering with the type strains of P. byunsanensis and P. amylolytica. Strain JBTF-M23T exhibited the highest 16S rRNA gene sequence similarity value (98.6 %) to the type strain of P. rubra and sequence similarities of 98.3 and 97.7 % to the type strains of P. byunsanensis and P. amylolytica, respectively. The DNA G+C content of strain JBTF-M23T from genomic sequence data was 41.98 %. The ANI and dDDH values between strain JBTF-M23T and the type strains of P. rubra, P. byunsanensis and P. amylolytica were 71.3-76.6 and 19.4-19.9 %, respectively. Strain JBTF-M23T contained Q-8 as the predominant ubiquinone and C16 : 1 ω7c and/or C16 : 1 ω6c, C16 : 0 and C18 : 1 ω7c as the major fatty acids. The major polar lipids of strain JBTF-M23T were phosphatidylethanolamine and one unidentified aminolipid. Distinguished phenotypic properties, along with the phylogenetic and genetic distinctiveness, revealed that strain JBTF-M23T is separated from recognized Pseudoalteromonas species. On the basis of the data presented, strain JBTF-M23Tis considered to represent a novel species of the genus Pseudoalteromonas, for which the name Pseudoalteromonas caenipelagi sp. nov. is proposed. The type strain is JBTF-M23T(=KACC 19900T=NBRC 113647T).

Shewanella insulae sp. nov., isolated from a tidal flat.

A Gram-stain-negative, aerobic, non-spore-forming, motile by single polar flagellum and ovoid or rod-shaped bacterial strain, designated JBTF-M18T, was isolated from tidal-flat sediment collected from the Yellow Sea, Republic of Korea. The neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain JBTF-M18T fell within the clade comprising the type strains of Shewanella species. Strain JBTF-M18T exhibited 16S rRNA gene sequence similarity values of 97.1-98.8 % to the type strains of S. loihica, S. aquimarina, S. waksmanii and S. marisflavi and of less than 96.9 % to the type strains of the other Shewanella species. The average nucleotide identity and digital DNA-DNA hybridization values between strain JBTF-M18T and the type strains of S. waksmanii and S. loihica were 72.0 and 89.5% and 18.9 and 38.1 %, respectively. DNA-DNA relatedness values between strain JBTF-M18T and the type strains of S. aquimarina and S. marisflavi were 14 and 19 %, respectively. The DNA G+C content of strain JBTF-M18T from genomic sequence data was 52.9 %. Strain JBTF-M18Tcontained MK-6 as the predominant menaquinone and Q-7 and Q-8 as the predominant ubiquinones. It had iso-C15 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and C16 : 0 as the major fatty acids. The major polar lipids of strain JBTF-M18T were phosphatidylethanolamine and phosphatidylglycerol. Distinguished phenotypic properties, along with the phylogenetic and genetic distinctiveness, revealed that strain JBTF-M18T is separated from recognized Shewanella species. On the basis of the data presented, strain JBTF-M18T is considered to represent a novel species of the genus Shewanella, for which the name Shewanella insulae sp. nov. is proposed. The type strain is JBTF-M18T (=KACC 19869T=NBRC 113583T).