Paucibacter sediminis sp. nov., isolated from sediment in a freshwater pond.

A Gram-stain-negative, aerobic, oxidase-positive, weakly catalase-positive, motile by means of a single polar flagellum, rod-shaped bacterium designated as strain S2-9T was isolated from sediment sampled in Wiyang pond, Republic of Korea. Growth of this strain was observed at 10-40 °C (optimum, 35 °C) and pH 5.5-9.5 (optimum, pH 7.0-8.0) and in the presence of 0-0.5 % NaCl in Reasoner's 2A broth. The major fatty acids (>10 %) of strain S2-9T were C16 : 0 and summed feature 3 (comprising a mixture of C16 : 1 ω7c and/or C16 : 1 ω6c). Ubiquinone-8 was detected as the respiratory quinone. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Strain S2-9T showed the highest 16S rRNA gene sequence similarity to Paucibacter oligotrophus CHU3T (98.7 %), followed by 'Paucibacter aquatile' CR182 (98.4 %), all type strains of Pelomonas species (98.1-98.3 %), Mitsuaria chitosanitabida NBRC 102408T (97.9 %), Kinneretia asaccharophila KIN192T (97.8 %), Mitsuaria chitinivorans HWN-4T (97.4 %), and Paucibacter toxinivorans 2C20T (97.4 %). Phylogenetic trees based on the 16S rRNA gene and whole-genome sequences showed that strain S2-9T formed a tight phylogenetic lineage with Paucibacter species (CHU3T, CR182, and 2C20T). Average nucleotide identity and digital DNA-DNA hybridization values between strain S2-9T and Paucibacter strains were 76.6-79.3% and 19.5-21.5 %, respectively. The genomic DNA G+C content of strain S2-9T was 68.3 mol%. Notably, genes responsible for both sulphur oxidation and reduction and denitrification were found in the genome of strain S2-9T, suggesting that strain S2-9T is involved in the nitrogen and sulphur cycles in pond ecosystems. Based on the polyphasic taxonomic results, strain S2-9T represents a novel species of the genus Paucibacter, for which the name Paucibacter sediminis sp. nov. is proposed. The type strain is S2-9T (= KACC 22267T= JCM 34541T).

Tahibacter soli sp. nov., isolated from soil and Tahibacter amnicola sp. nov., isolated from freshwater.

Two Gram-stain-negative, facultative aerobic, catalase- and oxidase-positive, and non-motile rod bacteria, strains BLT and W38T, that were isolated from soil and freshwater, respectively, were taxonomically characterized. Both strains optimally grew at 30 °C and pH 7.0 in Reasoner's 2A medium and contained ubiquinone-8 as the sole respiratory quinone. As major fatty acids (>10 %), strain BLT contained iso-C15 : 0 and summed features 3 and 9 (comprising iso-C15 : 0 2-OH and/or C16 : 1 ω7c/ω6c and iso-C17 : 1 ω9c and/or C16 : 0 10-methyl, respectively), whereas strain W38T contained iso-C15 : 0, iso-C16 : 0 and summed feature 9. Diphosphatidylglycerol and phosphatidylmonomethylethanolamine as major polar lipids and phosphatidylethanolamine and phosphatidylglycerol as minor polar lipids were detected in both strains. The DNA G+C contents of strains BLT and W38T were 68.3 and 65.3 %, respectively. Phylogenetic analyses based on 16S rRNA gene and genome sequences revealed that strains BLT and W38T formed a tight phylogenetic lineage with Tahibacter species, and they shared 98.8 % 16S rRNA gene sequence similarity and 75.5 % average nucleotide identity (ANI) and 16.6 % digital DNA-DNA hybridization (dDDH) values, indicating that they are different species. Strains BLT and W38T were most closely related to Tahibacter caeni BUT-6T and Tahibacter aquaticus PYM5-11T with 97.7 and 98.0 % 16S rRNA gene sequence similarities, respectively. ANI and dDDH values between strain BLT and T. caeni BUT-6T and between strain W38T and T. aquaticus DSM 21667T were 78.5 and 21.6% and 75.3 and 21.0 %, respectively. Based on their phenotypic, chemotaxonomic and genomic properties, strains BLT and W38T represent two different novel species of the genus Tahibacter, for which the names Tahibacter soli sp. nov. and Tahibacter amnicola sp. nov. are proposed. The type strains of T. soli and T. amnicola are BLT (=KACC 22831T=JCM 35402T) and W38T (=KACC 22832T=JCM 35749T), respectively.

Solitalea lacus sp. nov., isolated from pond sediment.

A Gram-stain-negative, strictly aerobic, oxidase-positive, catalase-negative, motile by gliding, creamy white-pigmented bacterium, designated strain S2-8T, isolated from a sediment sample from a Wiyang pond in the Republic of Korea, was subjected to polyphasic taxonomic analysis. Growth was observed at 10-40 °C (optimum: 30 °C), pH 7-8 and 0-0.5% NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain S2-8T belonged to the family Sphingobacteriaceae in the phylum Bacteroidota and was closely related to Solitalea longa HR-AVT, Solitalea canadensis DSM 3403T and Solitalea koreensis R2A36-4T with 97.2, 96.7 and 93.7 % 16S rRNA gene sequence similarities, respectively. Average nucleotide identity and digital DNA-DNA hybridization values for these type strains were 72.0-75.2% and 21.2-21.9 %, respectively. The major respiratory quinone is menaquinone-7. The major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c). The major polar lipids were phosphatidylethanolamine, two unidentified amino acids and four unidentified lipids. The G+C content of genomic DNA was 37.9 mol%. Based on polyphasic taxonomic analysis, it was observed that strain S2-8T is a novel species belonging to the genus Solitalea, for which the name Solitalea lacus sp. nov. is proposed. The type strain is S2-8T (= KACC 22266T= JCM 34533T).

Attenuation of Methane Oxidation by Nitrogen Availability in Arctic Tundra Soils.

CH4 emission in the Arctic has large uncertainty due to the lack of mechanistic understanding of the processes. CH4 oxidation in Arctic soil plays a critical role in the process, whereby removal of up to 90% of CH4 produced in soils by methanotrophs can occur before it reaches the atmosphere. Previous studies have reported on the importance of rising temperatures in CH4 oxidation, but because the Arctic is typically an N-limited system, fewer studies on the effects of inorganic nitrogen (N) have been reported. However, climate change and an increase of available N caused by anthropogenic activities have recently been reported, which may cause a drastic change in CH4 oxidation in Arctic soils. In this study, we demonstrate that excessive levels of available N in soil cause an increase in net CH4 emissions via the reduction of CH4 oxidation in surface soil in the Arctic tundra. In vitro experiments suggested that N in the form of NO3- is responsible for the decrease in CH4 oxidation via influencing soil bacterial and methanotrophic communities. The findings of our meta-analysis suggest that CH4 oxidation in the boreal biome is more susceptible to the addition of N than in other biomes. We provide evidence that CH4 emissions in Arctic tundra can be enhanced by an increase of available N, with profound implications for modeling CH4 dynamics in Arctic regions.

Does the fixture thread depth affect the accuracy of implant placement during fully guided immediate implant placement?: A human cadaver study.

BACKGROUND: The fixture thread depth reportedly influences the primary stability of dental implant, but its effect on the positional accuracy in immediate implant placement has not been reported previously. MATERIALS AND METHODS: Fifty-six single-rooted, anterior and premolar teeth were extracted from six human cadavers, followed by installing either regular-threaded implants (RT group, N = 30) or deep-threaded implants (DT group, N = 26) completely relying on the surgical guide. Optical impressions taken after osteotomy and fixture installation were superimposed with the preoperative virtual planning data to measure the vertical, angular, platform and apex deviations that occurred during osteotomy and installation. RESULTS: While the osteotomy deviations were similar between the two groups, the angular and apex deviation of the DT group (2.67 ± 2.56°; 1.04 ± 0.49 mm, respectively) were significantly larger than those of the RT group (1.61 ± 1.04°; 0.67 ± 0.41 mm, respectively) during installation (p < .05). When the installation deviations were analysed in the anterior and premolar areas separately, the angular, platform and apex deviations of the DT group (3.05 ± 3.26°; 0.75 ± 0.32 mm; 1.08 ± 0.56 mm, respectively) were significantly larger than those of the RT group (1.56 ± 0.73°, 0.59 ± 0.28 mm; 0.62 ± 0.38 mm, respectively) in the anterior site (p < .05), whereas there was no significant intergroup difference in the premolar site. CONCLUSION: In immediate-implant surgery, using an implant with a deeper thread might increase the deviations during installation, especially in the anterior area.

Temporal Variations Rather than Long-Term Warming Control Extracellular Enzyme Activities and Microbial Community Structures in the High Arctic Soil.

In Arctic soils, warming accelerates decomposition of organic matter and increases emission of greenhouse gases (GHGs), contributing to a positive feedback to climate change. Although microorganisms play a key role in the processes between decomposition of organic matter and GHGs emission, the effects of warming on temporal responses of microbial activity are still elusive. In this study, treatments of warming and precipitation were conducted from 2012 to 2018 in Cambridge Bay, Canada. Soils of organic and mineral layers were collected monthly from June to September in 2018 and analyzed for extracellular enzyme activities and bacterial community structures. The activity of hydrolases was the highest in June and decreased thereafter over summer in both organic and mineral layers. Bacterial community structures changed gradually over summer, and the responses were distinct depending on soil layers and environmental factors; water content and soil temperature affected the shift of bacterial community structures in both layers, whereas bacterial abundance, dissolved organic carbon, and inorganic nitrogen did so in the organic layer only. The activity of hydrolases and bacterial community structures did not differ significantly among treatments but among months. Our results demonstrate that temporal variations may control extracellular enzyme activities and microbial community structure rather than the small effect of warming over a long period in high Arctic soil. Although the effects of the treatments on microbial activity were minor, our study provides insight that microbial activity may increase due to an increase in carbon availability, if the growing season is prolonged in the Arctic.

Companilactobacillus pabuli sp. nov., a lactic acid bacterium isolated from animal feed.

A Gram-positive, facultative anaerobic, catalase-negative, non-motile, non-spore-forming and rod-shaped lactic acid bacterium strain, denoted as NFFJ11T and isolated from total mixed fermentation feed in the Republic of Korea, was characterized through polyphasic approaches, including sequence analyses of the 16S rRNA gene and housekeeping genes (rpoA and pheS), determination of average nucleotide identity and in silico DNA-DNA hybridization, fatty acid methyl ester analysis, and phenotypic characterization. Phylogenetic analyses based on 16S rRNA, rpoA and pheS gene sequences revealed that strain NFFJ11T belonged to the genus Companilactobacillus. The 16S rRNA gene sequence of strain NFFJ11T exhibited high similarity to Companilactobacillus formosensis S215T (99.66 %), Companilactobacillus farciminis Rv4 naT (99.53 %), Companilactobacillus crustorum LMG 23699T (99.19 %), Companilactobacillus futsaii YM 0097T (99.06 %), Companilactobacillus zhachilii HBUAS52074T (98.86 %) and Companilactobacillus heilongiiangensis S4-3T (98.66 %). However, average nucleotide identity and in silico DNA-DNA hybridization values for these type strains were in the range of 79.90-92.93 % and 23.80-49.30 %, respectively, which offer evidence that strain NFFJ11T belongs to a novel species of the genus Companilactobacillus. The cell-wall peptidoglycan type was A4α (l-Lys-d-Asp) and the G+C content of the genomic DNA was 35.7 mol%. The main fatty acids of strain NFFJ11T were C18 : 1 ω9c (43.3 %), C16 : 0 (20.1 %) and summed feature 7 (18.3 %; comprising any combination of C19 : 1 ω7c, C19 : 1 ω6c and C19 : 0 cyclo ω10c). Through polyphasic taxonomic analysis, it was observed that strain NFFJ11T represents a novel species belonging to the genus Companilactobacillus, for which the name Companilactobacillus pabuli sp. nov. is proposed. The type strain is NFFJ11T (= KACC 21771T= JCM 34088T).

In vitro test systems to determine tetracycline residue binding to human feces.

The use of antimicrobials, such as tetracycline, in food-producing animals may result in antimicrobial drug residues (ADR) in edible tissues from treated animals and contribute to the emergence of antibiotic resistant bacteria. The Veterinary International Conference on Harmonization (VICH) document (VICH GL36(R)/FDA-CVM Guidance for Industry#159) provides guidance on evaluating the safety of veterinary ADR in the human foods as related to effects on the human intestinal microbiome. One recognized research gap is a need for additional data and testing requirements to determine the fraction of an oral dose of ADR available to intestinal microorganisms. In the present study, we address this need by examining the binding of tetracycline to human feces using chemical and microbiological assays. High-performance liquid chromatography and liquid chromatography mass spectrometry assays showed that 25% (w/v) diluted steam sterilized feces dosed with 0.15 and 1.5 µg/ml tetracycline had binding of 58.2 ±â€¯10.8% and 56.9 ±â€¯9.1%, respectively. Tetracycline binding to fecal slurries gave similar results. Microbiological assays with two reference bacterial strains validated the results of the chemical assays. Based on data from chemical and microbiological assays methods, the fraction of dose available to microorganisms was 0.418 and 0.431 of the 0.15 and 1.5 µg/ml tetracycline treatments, respectively. This study also proposes factors to be considered when designing and conducting experiments to determine the percent of an antimicrobial agents that is available to microorganisms in the gastrointestinal tract.

Nurses' needs for care robots in integrated nursing care services.

AIMS: To determine the need for care robots among nurses and to suggest how robotic care should be prioritized in integrated nursing care services. BACKGROUND: Korea is expected to be a super-aged society by 2030. To solve care issues with elderly inpatient caused by informal caregivers, the government introduced "integrated nursing care services"; these are comprehensive care systems staffed by professionally trained nurses. To assist them, a care robot development project has been launched. DESIGN: The study applied a cross-sectional survey. METHODS: In 2016, we conducted a multicentre survey involving 302 Registered Nurses in five hospitals including three tertiary and two secondary hospitals in Korea. The questionnaire consisted of general characteristics of nurses and their views on and extents of agreement about issues associated with robotic care. RESULTS: Trial centre nurses and those with ≥10 years of experience reported positively on the prospects for robotic care. The top-three desired primary roles for care robots were "measuring/monitoring", "mobility/activity" and "safety care". "Reduction in workload", especially in terms of "other nursing services" which were categorized as nonvalue-added nursing activities, was the most valued feature. The nurses approved of the aid by care robots but were concerned about device malfunction and interruption of rapport with patients. CONCLUSION: Care robots are expected to be effective in integrated nursing care services, particularly in "measuring/monitoring". Such robots should decrease nurses' workload and minimize nonvalue-added nursing activities efficiently. No matter how excellent care robots are, they must cooperate with and be controlled by nurses.

An in vitro study to assess the impact of tetracycline on the human intestinal microbiome.

The human intestinal microbiome, a generally stable ecosystem, could be potentially altered by the ingestion of antimicrobial drug residues in foods derived from animals. Data and the scientific published literature on the effects of antimicrobial residues on the human intestinal microbiome are reviewed by national regulatory authorities as part of the human food safety evaluation of veterinary antimicrobial agents used in food-producing animals. In this study, we determined if tetracycline, at low residue concentrations, could impact the human intestinal microbiome structure and the resistance-gene profile, following acute and subchronic exposure. The effects of 0.15, 1.5, 15, and 150 µg/ml of tetracycline, after 24 h and 40 days of exposure, in 3% human fecal suspensions, collected from three individuals (A, B, and C) were investigated using in vitro batch cultures. Results were variable, with either no change or minor changes in total bacterial 16S rRNA gene copies after exposure of fecal samples to tetracycline, because of the inter-individual variation of human gastrointestinal tract microbiota. Bacterial community analysis using rRNA-based pyrosequencing revealed that Firmicutes and Bacteroidetes were the predominant phyla in the three fecal samples; the ratio of phylotypes varied among individuals. The evaluation of bacterial community changes at the genus level, from control to tetracycline-treated fecal samples, suggested that tetracycline under the conditions of this study could lead to slight differences in the composition of intestinal microbiota. The genus Bacteroides (of the Bacteroidetes) was consistently altered from 1.68 to 5.70% and 4.82-8.22% at tetracycline concentrations of 0.15 µg/ml or above at both time points for individual A, respectively, and increased 5.13-13.50% and 10.92-22.18% for individual B, respectively. Clostridium family XI increased 3.50-25.34% in the presence of tetracycline at 40 days for individual C. Principal Component Analysis (PCA) confirmed the pyrosequencing findings of inter-individual variability of the ratio of phylotypes and the effect of tetracycline. Among the 23 tetracycline resistance genes (TRGs) screened, four tet genes (tetO, Q, W, and X) were major TRGs in control and tetracycline-dosed fecal samples. A variable to slight increase of copy number of TRGs appeared to be related to tetracycline treatment, interindividual variability and duration of exposure. Despite, the inherent variability of the intestinal microbiota observed among or within individuals, this pilot study contributes to the knowledge base of the impact of low residue concentrations of tetracycline on the human intestinal microbiome on the potential for antimicrobial resistance.

Counter-Based Broadcast Scheme Considering Reachability, Network Density, and Energy Efficiency for Wireless Sensor Networks.

A wireless sensor network (WSN) is emerging as an innovative method for gathering information that will significantly improve the reliability and efficiency of infrastructure systems. Broadcast is a common method to disseminate information in WSNs. A variety of counter-based broadcast schemes have been proposed to mitigate the broadcast-storm problems, using the count threshold value and a random access delay. However, because of the limited propagation of the broadcast-message, there exists a trade-off in a sense that redundant retransmissions of the broadcast-message become low and energy efficiency of a node is enhanced, but reachability become low. Therefore, it is necessary to study an efficient counter-based broadcast scheme that can dynamically adjust the random access delay and count threshold value to ensure high reachability, low redundant of broadcast-messages, and low energy consumption of nodes. Thus, in this paper, we first measure the additional coverage provided by a node that receives the same broadcast-message from two neighbor nodes, in order to achieve high reachability with low redundant retransmissions of broadcast-messages. Second, we propose a new counter-based broadcast scheme considering the size of the additional coverage area, distance between the node and the broadcasting node, remaining battery of the node, and variations of the node density. Finally, we evaluate performance of the proposed scheme compared with the existing counter-based broadcast schemes. Simulation results show that the proposed scheme outperforms the existing schemes in terms of saved rebroadcasts, reachability, and total energy consumption.

Bio-Inspired Distributed Transmission Power Control Considering QoS Fairness in Wireless Body Area Sensor Networks.

Recently, the development of wireless body area sensor network (WBASN) has accelerated due to the rapid development of wireless technology. In the WBASN environment, many WBASNs coexist where communication ranges overlap with each other, resulting in the possibility of interference. Although nodes in a WBASN typically operate at a low power level, to avoid adversely affecting the human body, high transmission rates may be required to support some applications. In addition to this, since many varieties of applications exist in the WBASN environment, each prospective user may have different quality of service (QoS) requirements. Hence, the following issues should be considered in the WBASN environment: (1) interference between adjacent WBASNs, which influences the performance of a specific system, and (2) the degree of satisfaction on the QoS of each user, i.e., the required QoS such as user throughput should be considered to ensure that all users in the network are provided with a fair QoS satisfaction. Thus, in this paper, we propose a transmission power adjustment algorithm that addresses interference problems and guarantees QoS fairness between users. First, we use a new utility function to measure the degree of the satisfaction on the QoS for each user. Then, the transmission power of each sensor node is calculated using the Cucker-Smale model, and the QoS satisfaction of each user is synchronized dispersively. The results of simulations show that the proposed algorithm performs better than existing algorithms, with respect to QoS fairness and energy efficiency.

Sensitive change of iso-branched fatty acid (iso-15:0) in Bacillus pumilus PAMC 23174 in response to environmental changes.

In this study, the environmental adaptive metabolic processes were investigated using a psychrotrophic polar bacterium Bacillus pumilus PAMC 23174 in response to various temperatures and nutrients, especially in regard to the synthesis of fatty acids. Fatty acid methyl ester analysis was performed using gas chromatography-mass spectrometry and we found that a sensitive changes in iso-branched fatty acid (iso-15:0) synthesis occurred when adjusting the nutritional ratio of branched chain fatty acids (anteiso/iso) with different temperatures, resulting in a change in the balance of anteiso- and iso-form fatty acids. We also observed that this Arctic bacterium preferred amino acid leucine for the synthesis of fatty acids. The increased and decreased synthesis of iso-form fatty acids in response to different temperatures and leucine preference, changes the fatty acid ratio in bacteria, which further affects the membrane fluidity and it is also directly correlated with survival of bacteria in an extreme environment. Hence, this study suggests that B. pumilus PAMC 23174 is a potential model organism for the analysis of the unique ecological adaptations of polar bacteria in changing and the extreme environments.

Dynamic Power-Saving Method for Wi-Fi Direct Based IoT Networks Considering Variable-Bit-Rate Video Traffic.

With the arrival of the era of Internet of Things (IoT), Wi-Fi Direct is becoming an emerging wireless technology that allows one to communicate through a direct connection between the mobile devices anytime, anywhere. In Wi-Fi Direct-based IoT networks, all devices are categorized by group of owner (GO) and client. Since portability is emphasized in Wi-Fi Direct devices, it is essential to control the energy consumption of a device very efficiently. In order to avoid unnecessary power consumed by GO, Wi-Fi Direct standard defines two power-saving methods: Opportunistic and Notice of Absence (NoA) power-saving methods. In this paper, we suggest an algorithm to enhance the energy efficiency of Wi-Fi Direct power-saving, considering the characteristics of multimedia video traffic. Proposed algorithm utilizes the statistical distribution for the size of video frames and adjusts the lengths of awake intervals in a beacon interval dynamically. In addition, considering the inter-dependency among video frames, the proposed algorithm ensures that a video frame having high priority is transmitted with higher probability than other frames having low priority. Simulation results show that the proposed method outperforms the traditional NoA method in terms of average delay and energy efficiency.

Dibenzothiopheno[6,5-b:6',5'-f]thieno[3,2-b]thiophene (DBTTT): high-performance small-molecule organic semiconductor for field-effect transistors.

We present the synthesis, characterization, and structural analysis of a thiophene-rich heteroacene, dibenzothiopheno[6,5-b:6',5'-f]thieno[3,2-b]thiophene (DBTTT) as well as its application in field-effect transistors. The design of DBTTT is based on the enhancement of intermolecular charge transfer through strong S-S interactions. Crystal structure analysis showed that the intermolecular π-π distance is shortened and that the packing density is higher than those of the electronically equivalent benzene analogue, dinaphtho-[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT). The highest hole mobility we obtained in polycrystalline DBTTT thin-film transistors was 19.3 cm(2)·V(-1)·s(-1), six times higher than that of DNTT-based transistors. The observed isotropic angular mobilities and thermal stabilities at temperatures up to 140 °C indicate the great potential of DBTTT for attaining device uniformity and processability.

Garicola koreensis gen. nov., sp. nov., isolated from saeu-jeot, traditional Korean fermented shrimp.

A novel Gram-staining-positive, non-endospore-forming, aerobic bacterium, designated strain SJ5-4(T), was isolated from seau-jeot, a traditional food that is made by fermentation of highly salted [approximately 25 % (w/v)] shrimp in Korea. Cells were moderately halophilic, non-motile cocci or short rods that showed catalase- and oxidase-positive reactions. Growth of strain SJ5-4(T) was observed at 15-40 °C (optimum, 30 °C), at pH 6.0-9.5 (optimum, pH 6.5-7.0) and in the presence of 1-17 % (w/v) NaCl (optimum, 6 %). The major cellular fatty acids of strain SJ5-4(T) were anteiso-C15 : 0, iso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0 and C16 : 0. Phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, an unidentified phospholipid, three glycolipids and an unidentified lipid were detected as the polar lipids. Strain SJ5-4(T) belonged to the exceptionally small group of strains within the order Micrococcales that show a peptidoglycan cross-linked according to the A-type but containing 2,4-diaminobutyric acid. The G+C content of the genomic DNA was 61.8 mol%. MK-7, MK-8 and MK-9 were detected as the isoprenoid quinones. Strain SJ5-4(T) was most closely related to members of the genus Nesterenkonia, with 16S rRNA gene sequence similarities of 93.1-94.8 %. However, phylogenetic inference based on 16S rRNA gene sequences showed that strain SJ5-4(T) formed a phyletic lineage distinct from members of the genus Nesterenkonia within the family Micrococcaceae. On the basis of its phenotypic and molecular features, strain SJ5-4(T) represents a novel genus and species of the family Micrococcaceae, for which the name Garicola koreensis gen. nov., sp. nov. is proposed. The type strain of Garicola koreensis is SJ5-4(T) ( = KACC 16909(T) = JCM 18572(T) = DSM 28238(T)).

Chronic sleep deprivation-induced proteome changes in astrocytes of the rat hypothalamus.

Sleep deprivation (SD) can influence cognition, memory, and sleep/wake homeostasis and can cause impairments in many physiological processes. Because the homeostatic control of the sleep/wake cycle is closely associated with the hypothalamus, the current study was undertaken to examine proteomic changes occurring in hypothalamic astrocytes following chronic partial SD. After chronic partial SD for 7 days, astrocytes were prepared from rat hypothalamus using a Percoll gradient method, and their proteome profiles were determined by LC-MS/MS. Comparisons of the proteome profiles of hypothalamic astrocytes revealed that chronic partial SD increased (≥1.5-fold) 89 proteins and decreased (≤0.7-fold) 50 proteins; these changes in protein expression were validated by western blot or immunohistochemistry. DAVID and IPA analyses of these proteins suggested that SD may influence gliotransmission and astrocyte activation. PPP2R1A, RTN4, VAMP-2, LGI-1, and SLC17A7 were identified and validated as the main targets of SD in astrocytes. Our results suggest that SD may modulate gliotransmission in the hypothalamus, thereby disturbing sleep/wake homeostasis and increasing susceptibility to neurological disease; however, further studies are required to confirm whether the proteome changes are specific to SD.

Kimchi microflora: history, current status, and perspectives for industrial kimchi production.

Kimchi, a traditional Korean food made by the fermentation of vegetables, has become popular globally because of its organoleptic, beneficial, and nutritional properties. Spontaneous kimchi fermentation in unsterilized raw materials leads to the growth of various lactic acid bacteria (LAB), which results in variations in the taste and sensory qualities of kimchi products and difficulties in the standardized industrial production of kimchi. Raw materials, kimchi varieties, ingredients, and fermentation conditions have significant effects on the microbial communities and fermentative characteristics of kimchi during fermentation. Heterofermentative LAB belonging to the genera Leuconostoc, Lactobacillus, and Weissella are likely to be key players in kimchi fermentation and have been subjected to genomic and functional studies to gain a better understanding of the fermentation process and beneficial effects of kimchi. The use of starter cultures has been considered for the industrial production of high quality, standardized kimchi. Here, we review the composition and biochemistry of kimchi microflora communities, functional and genomic studies of kimchi LAB, and perspectives for industrial kimchi production.

Effects of temperature on microbial succession and metabolite change during saeu-jeot fermentation.

To investigate the effects of temperature on saeu-jeot (shrimp) fermentation, four sets of saeu-jeot samples with approximately 25% (w/v) NaCl were fermented at 10 °C, 15 °C, 20 °C, and 25 °C. The pH values of the 10 °C and 15 °C samples were relatively constant during the entire fermentation period, whereas those of the 20 °C and 25 °C samples gradually decreased after 25 days of fermentation. Quantitative PCR showed that the maximum bacterial abundance was greater in higher temperature samples, and the bacterial abundance in the 10 °C samples steadily decreased during the entire fermentation period. Community analysis using pyrosequencing revealed that the initially dominant Proteobacteria including Pseudoalteromonas, Photobacterium, Vibrio, Aliivibrio, and Enterovibrio were replaced rapidly with Firmicutes such as Psychrobacter, Staphylococcus, Salimicrobium, Alkalibacillus, and Halanaerobium as the fermentation progressed. However, Vibrio, Photobacterium, Aliivibrio, and Enterovibrio, which may include potentially pathogenic strains, remained even after 215 days in the 10 °C samples. Metabolite analysis using (1)H NMR showed that amino acid profiles and initial quick increases of glucose and glycerol were similar and independent of bacterial growth in all temperature samples. After 25 days of fermentation, the levels of glucose, glycerol, and trimethylamine N-oxide decreased with the growth of Halanaerobium and the increase of acetate, butyrate, and methylamines in the 20 °C and 25 °C samples although the amino acid concentrations steadily increased until approximately 105 days of fermentation. Statistical triplot analysis showed that the bacterial successions occurred similarly regardless of the fermentation temperature, and Halanaerobium was likely responsible for the production of acetate, butyrate, and methylamines. This study suggests that around 15 °C might be the optimum temperature for the production of safe and tasty saeu-jeot.

Complete genome sequence of Levilactobacillus brevis NSMJ23, makgeolli isolate with antimicrobial activity.

We report the complete genome sequence of Levilactobacillus brevis NSMJ23 with probiotic properties. The final genome assembly consisted of a 2,389,998-bp chromosome and seven plasmids with 45.59% GC content, which comprised 2,624 genes including 2,457 protein coding sequences.