The convergent application of metabolites from Avena sativa and gut microbiota to ameliorate non-alcoholic fatty liver disease: a network pharmacology study.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a serious public health issue globally, currently, the treatment of NAFLD lies still in the labyrinth. In the inchoate stage, the combinatorial application of food regimen and favorable gut microbiota (GM) are considered as an alternative therapeutic. Accordingly, we integrated secondary metabolites (SMs) from GM and Avena sativa (AS) known as potent dietary grain to identify the combinatorial efficacy through network pharmacology. METHODS: We browsed the SMs of AS via Natural Product Activity & Species Source (NPASS) database and SMs of GM were retrieved by gutMGene database. Then, specific intersecting targets were identified from targets related to SMs of AS and GM. The final targets were selected on NAFLD-related targets, which was considered as crucial targets. The protein-protein interaction (PPI) networks and bubble chart analysis to identify a hub target and a key signaling pathway were conducted, respectively. In parallel, we analyzed the relationship of GM or AS─a key signaling pathway─targets─SMs (GASTM) by merging the five components via RPackage. We identified key SMs on a key signaling pathway via molecular docking assay (MDA). Finally, the identified key SMs were verified the physicochemical properties and toxicity in silico platform. RESULTS: The final 16 targets were regarded as critical proteins against NAFLD, and Vascular Endothelial Growth Factor A (VEGFA) was a key target in PPI network analysis. The PI3K-Akt signaling pathway was the uppermost mechanism associated with VEGFA as an antagonistic mode. GASTM networks represented 122 nodes (60 GM, AS, PI3K-Akt signaling pathway, 4 targets, and 56 SMs) and 154 edges. The VEGFA-myricetin, or quercetin, GSK3B-myricetin, IL2-diosgenin complexes formed the most stable conformation, the three ligands were derived from GM. Conversely, NR4A1-vestitol formed stable conformation with the highest affinity, and the vestitol was obtained from AS. The given four SMs were no hurdles to develop into drugs devoid of its toxicity. CONCLUSION: In conclusion, we show that combinatorial application of AS and GM might be exerted to the potent synergistic effects against NAFLD, dampening PI3K-Akt signaling pathway. This work provides the importance of dietary strategy and beneficial GM on NAFLD, a data mining basis for further explicating the SMs and pharmacological mechanisms of combinatorial application (AS and GM) against NAFLD.

Identification of Gut Microbiome Metabolites via Network Pharmacology Analysis in Treating Alcoholic Liver Disease.

Alcoholic liver disease (ALD) is linked to a broad spectrum of diseases, including diabetes, hypertension, atherosclerosis, and even liver carcinoma. The ALD spectrum includes alcoholic fatty liver disease (AFLD), alcoholic hepatitis, and cirrhosis. Most recently, some reports demonstrated that the pathogenesis of ALD is strongly associated with metabolites of human microbiota. AFLD was the onset of disease among ALDs, the initial cause of which is alcohol consumption. Thus, we analyzed the significant metabolites of microbiota against AFLD via the network pharmacology concept. The metabolites from microbiota were retrieved by the gutMGene database; sequentially, AFLD targets were identified by public databases (DisGeNET, OMIM). The final targets were utilized for protein-protein interaction (PPI) networks and signaling pathway analyses. Then, we performed a molecular docking test (MDT) to verify the affinity between metabolite(s) and target(s) utilizing the Autodock 1.5.6 tool. From a holistic viewpoint, we integrated the relationships of microbiota-signaling pathways-targets-metabolites (MSTM) using the R Package. We identified the uppermost six key targets (TLR4, RELA, IL6, PPARG, COX-2, and CYP1A2) against AFLD. The PPI network analysis revealed that TLR4, RELA, IL6, PPARG, and COX-2 had equivalent degrees of value (4); however, CYP1A2 had no associations with the other targets. The bubble chart showed that the PI3K-Akt signaling pathway in nine signaling pathways might be the most significant mechanism with antagonistic functions in the treatment of AFLD. The MDT confirmed that Icaritin is a promising agent to bind stably to RELA (known as NF-Κb). In parallel, Bacterium MRG-PMF-1, the PI3K-Akt signaling pathway, RELA, and Icaritin were the most significant components against AFLD in MSTM networks. In conclusion, we showed that the Icaritin-RELA complex on the PI3K-Akt signaling pathway by bacterial MRG-PMF-1 might have promising therapeutic effects against AFLD, providing crucial evidence for further research.

The Link between Gut Microbiota and Hepatic Encephalopathy.

Hepatic encephalopathy (HE) is a serious complication of cirrhosis that causes neuropsychiatric problems, such as cognitive dysfunction and movement disorders. The link between the microbiota and the host plays a key role in the pathogenesis of HE. The link between the gut microbiome and disease can be positively utilized not only in the diagnosis area of HE but also in the treatment area. Probiotics and prebiotics aim to resolve gut dysbiosis and increase beneficial microbial taxa, while fecal microbiota transplantation aims to address gut dysbiosis through transplantation (FMT) of the gut microbiome from healthy donors. Antibiotics, such as rifaximin, aim to improve cognitive function and hyperammonemia by targeting harmful taxa. Current treatment regimens for HE have achieved some success in treatment by targeting the gut microbiota, however, are still accompanied by limitations and problems. A focused approach should be placed on the establishment of personalized trial designs and therapies for the improvement of future care. This narrative review identifies factors negatively influencing the gut-hepatic-brain axis leading to HE in cirrhosis and explores their relationship with the gut microbiome. We also focused on the evaluation of reported clinical studies on the management and improvement of HE patients with a particular focus on microbiome-targeted therapy.

Microbiome-Based Metabolic Therapeutic Approaches in Alcoholic Liver Disease.

Alcohol consumption is a global healthcare problem. Chronic alcohol consumption generates a wide spectrum of hepatic lesions, the most characteristic of which are steatosis, hepatitis, fibrosis, and cirrhosis. Alcoholic liver diseases (ALD) refer to liver damage and metabolomic changes caused by excessive alcohol intake. ALD present several clinical stages of severity found in liver metabolisms. With increased alcohol consumption, the gut microbiome promotes a leaky gut, metabolic dysfunction, oxidative stress, liver inflammation, and hepatocellular injury. Much attention has focused on ALD, such as alcoholic fatty liver (AFL), alcoholic steatohepatitis (ASH), alcoholic cirrhosis (AC), hepatocellular carcinoma (HCC), a partnership that reflects the metabolomic significance. Here, we report on the global function of inflammation, inhibition, oxidative stress, and reactive oxygen species (ROS) mechanisms in the liver biology framework. In this tutorial review, we hypothetically revisit therapeutic gut microbiota-derived alcoholic oxidative stress, liver inflammation, inflammatory cytokines, and metabolic regulation. We summarize the perspective of microbial therapy of genes, gut microbes, and metabolic role in ALD. The end stage is liver transplantation or death. This review may inspire a summary of the gut microbial genes, critical inflammatory molecules, oxidative stress, and metabolic routes, which will offer future promising therapeutic compounds in ALD.

The Gut Microbiota-Derived Immune Response in Chronic Liver Disease.

In chronic liver disease, the causative factor is important; however, recently, the intestinal microbiome has been associated with the progression of chronic liver disease and the occurrence of side effects. The immune system is affected by the metabolites of the microbiome, and diet is the primary regulator of the microbiota composition and function in the gut-liver axis. These metabolites can be used as therapeutic material, and postbiotics, in the future, can increase or decrease human immunity by modulating inflammation and immune reactions. Therefore, the excessive intake of nutrients and the lack of nutrition have important effects on immunity and inflammation. Evidence has been published indicating that microbiome-induced chronic inflammation and the consequent immune dysregulation affect the development of chronic liver disease. In this research paper, we discuss the overall trend of microbiome-derived substances related to immunity and the future research directions.

T Cell Subsets and Natural Killer Cells in the Pathogenesis of Nonalcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) is a condition characterized by hepatic accumulation of excess lipids. T cells are commonly classified into various subsets based on their surface markers including T cell receptors, type of antigen presentation and pathophysiological functions. Several studies have implicated various T cell subsets and natural killer (NK) cells in the progression of NAFLD. While NK cells are mainly components of the innate hepatic immune system, the majority of T cell subsets can be part of both the adaptive and innate systems. Several studies have reported that various stages of NAFLD are accompanied by the accumulation of distinct T cell subsets and NK cells with different functions and phenotypes observed usually resulting in proinflammatory effects. More importantly, the overall stimulation of the intrahepatic T cell subsets is directly influenced by the homeostasis of the gut microbiota. Similarly, NK cells have been found to accumulate in the liver in response to pathogens and tumors. In this review, we discussed the nature and pathophysiological roles of T cell subsets including γδ T cells, NKT cells, Mucosal-associated invariant T (MAIT) cells as well as NK cells in NAFLD.

Diet-Regulating Microbiota and Host Immune System in Liver Disease.

The gut microbiota has been known to modulate the immune responses in chronic liver diseases. Recent evidence suggests that effects of dietary foods on health care and human diseases are related to both the immune reaction and the microbiome. The gut-microbiome and intestinal immune system play a central role in the control of bacterial translocation-induced liver disease. Dysbiosis, small intestinal bacterial overgrowth, translocation, endotoxemia, and the direct effects of metabolites are the main events in the gut-liver axis, and immune responses act on every pathways of chronic liver disease. Microbiome-derived metabolites or bacteria themselves regulate immune cell functions such as recognition or activation of receptors, the control of gene expression by epigenetic change, activation of immune cells, and the integration of cellular metabolism. Here, we reviewed recent reports about the immunologic role of gut microbiotas in liver disease, highlighting the role of diet in chronic liver disease.

Lewinella litorea sp. nov., isolated from marine sand.

A Gram-stain-negative, aerobic, non-motile and ovoid- or rod-shaped bacterial strain, designated HSMS-39T, was isolated from marine sand sampled at Hongsung, Republic of Korea. Strain HSMS-39T grew optimally at 30 °C and in the presence of 1.0-2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences showed that strain HSMS-39T fell within the clade comprising the type strains of Lewinella species, clustering with the type strain of Lewinella marina showing 16S rRNA gene sequence similarity of 99.1 %. It exhibited 16S rRNA gene sequence similarities of less than 95.5 % to the type strains of the other Lewinella species. Strain HSMS-39T contained MK-7 as the predominant menaquinone and iso-C17 : 1ω9c, iso-C15 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as the major fatty acids. The major polar lipids of strain HSMS-39T were phosphatidylethanolamine and one unidentified phospholipid. The DNA G+C content of strain HSMS-39T was 60.0 mol%. The mean DNA-DNA relatedness value between strain HSMS-39T and the type strain of L. marina was 15 %. The average nucleotide identity value between strain HSMS-39Tand the type strain of L. marina was 81.87 %. The phylogenetic and genetic data and differential phenotypic properties indicated that strain HSMS-39T is separated from other recognized species of the genus Lewinella. On the basis of the polyphasic data, strain HSMS-39T is considered to represent a novel species of the genus Lewinella, for which the name Lewinella litorea sp. nov. is proposed. The type strain is HSMS-39T (=KACC 19866T=NBRC 113585T).

Croceicoccus ponticola sp. nov., a lipolytic bacterium isolated from seawater.

A lipolytic, Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated GM-16T, was isolated from seawater around Pohang in the Republic of Korea. Strain GM-16T grew optimally at 30 °C and in the presence of 1.0-2.0 % (w/v) NaCl. The neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain GM-16T fell within the clade comprising the type strains of Croceicoccus species. Strain GM-16T exhibited the highest 16S rRNA gene sequence similarity (97.7 %) to the type strain of Croceicoccus pelagius and sequence similarities of 96.3-96.7 % to the type strains of the other Croceicoccus species. Strain GM-16T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as major fatty acids. The major polar lipids of strain GM-16T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid and one unidentified glycolipid. The DNA G+C content of strain GM-16T was 62.6 mol%. The mean DNA-DNA relatedness value between strain GM-16T and C. pelagius DSM 101479T was 16 %. The average nucleotide identity values between strain GM-16T and the type strains of C.roceicoccus pelagius, C.roceicoccus marinus, C.roceicoccus naphthovorans and C.roceicoccus mobilis were 83.96-84.44 %. The phylogenetic and genetic data and differential phenotypic properties indicated that strain GM-16T is separated from recognized Croceicoccus species. On the basis of the data presented here, strain GM-16T is considered to represent a novel species of the genus Croceicoccus, for which the name Croceicoccus ponticola sp. nov. is proposed. The type strain is GM-16T (=KACC 19611T=KCTC 62423T=NBRC 113192T).

Erythrobacter marisflavi sp. nov., isolated from isolated from estuary water.

A Gram-stain-negative, aerobic, non-motile and coccoid-, ovoid- or rod-shaped bacterial strain, designated KEM-5T, was isolated from water sampled at an estuary environment on the Yellow Sea, Republic of Korea. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain KEM-5T fell within the clade comprising the type strains of Erythrobacter species. Strain KEM-5T exhibited 16S rRNA gene sequence similarities of 97.01-97.66 % to the type strains of E.rythrobacter citreus, E.rythrobacter seohaensis and E.rythrobacter pelagi and of 94.18-96.95 % to the type strains of the other Erythrobacter species. The genomicaverage nucleotide identity values of strain KEM-5T with a non-type strain (LAMA 915) of E. citreus and E. seohaensis SW-135T were 76.04 and 74.98 %, respectively. Mean DNA-DNA relatedness values between strain KEM-5T and the type strains of E. citreus, E. seohaensis and E. pelagi were 10-18 %. Strain KEM-5T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C17 : 1ω6c as the major fatty acids. The major polar lipids of strain KEM-5T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid. The DNA G+C content of strain KEM-5T was 62.4 mol%. Distinguishing phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain KEM-5T is separated from recognized Erythrobacter species. On the basis of the data presented here, strain KEM-5T is considered to represent a novel species of the genus Erythrobacter, for which the name Erythrobacter marisflavi sp. nov. is proposed. The type strain is KEM-5T (=KACC 19865T=KCTC 62896T=NBRC 113546T).

Paenimaribius caenipelagi gen. nov., sp. nov., isolated from a tidal flat.

A Gram-stain-negative, strictly aerobic, non-motile and ovoid- or rod-shaped bacterial strain, JBTF-M29T, was isolated from tidal flat sediment sampled from the Yellow Sea, Republic of Korea. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain JBTF-M29T clustered with the type strains of Maribius species and this cluster joined the clade comprising Pseudomaribius and Palleronia species. Strain JBTF-M29T exhibited 16S rRNA gene sequence similarity values of 96.2-96.6 % to the type strains of three Maribius species, of 96.4 % to the type strain of Pseudomaribius aestuariivivens and of 93.9-94.7 % to the type strains of three Palleronia species. In the UPGMA dendrogram based on the ANI values of genomic sequences, strain JBTF-M29T formed an evolutionary lineage independent of the genera Maribius and Palleronia and some other taxa. Strain JBTF-M29T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c and C18 : 0 as the major fatty acids. The major polar lipids of strain JBTF-M29T were phosphatidylglycerol and one unidentified aminolipid. The DNA G+C content of strain JBTF-M29T was 64.5 mol%. The differences in fatty acid and polar lipid profiles and other differential phenotypic properties including nitrate reduction and casein hydrolysis made it reasonable to distinguish strain JBTF-M29T from the genera Maribius, Pseudomaribius and Palleronia. Therefore, on the basis of the polyphasic taxonomic data presented here, strain JBTF-M29T constitutes a new genus and species within the class Alphaproteobacteria, for which the name Paenimaribius caenipelagi gen. nov., sp. nov. is proposed. The type strain is JBTF-M29T (=KACC 19867T=NBRC 113548T).

Aliishimia ponticola gen. nov., sp. nov., isolated from seawater.

A Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated MYP11T, was isolated from seawater around Jeju island, Republic of Korea and identified by polyphasic taxonomic study. A neighbour-joining phylogenetic tree of 16S rRNA gene sequences showed that strain MYP11T joined the cluster comprising the type strains of Shimiaabyssi, Shimiaaestuarii and Shimiaaquaeponti, showing 16S rRNA gene sequence similarities of 96.3-96.8 %. Strain MYP11T exhibited 16S rRNA gene sequence similarity values of 94.2-94.9 % to the type strains of other Shimia species. In the upgma dendrogram based on the average nucleotide identity values of genomic sequences, strain MYP11T formed an evolutionary lineage independent of those of Shimia species and other taxa. Strain MYP11T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c and cyclo C19 : 0 ω8c as the major fatty acids. The major polar lipids of strain MYP11T were phosphatidylcholine, phosphatidylglycerol, two unidentified lipids and one unidentified aminolipid. The DNA G+C content of strain MYP11T was 63.1 or 61.5 mol%. The differences in the fatty acid and polar lipid profiles and DNA G+C contents made it reasonable to distinguish strain MYP11T from the type strains of S. abyssi, S. aestuarii and S. aquaeponti and those of other Shimia species. On the basis of the polyphasic data presented here, strain MYP11T is considered to constitute a new genus and species within the class Alphaproteobacteria, for which the name Aliishimia ponticola gen. nov., sp. nov. is proposed. The type strain is MYP11T (=KCTC 62899T=NBRC 113544T).

Jannaschia confluentis sp. nov., isolated from the junction between the ocean and a freshwater spring.

A Gram-stain-negative, aerobic, non-motile and ovoid or rod-shaped bacterial strain, designated JSSK-16T, was isolated from the place where the ocean and a freshwater spring meet at Jeju Island, South Korea. Strain JSSK-16T grew optimally at 30 °C, at pH 6.5-8.0 and in the presence of 2.0-4.0 % (w/v) NaCl. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain JSSK-16T joined the clade comprising the type strains of Jannaschia species. Strain JSSK-16T exhibited 16S rRNA gene sequence similarity values of 97.5 and 97.1 % to the type strains of Jannaschia donghaensis and Jannaschia faecimaris, respectively, and of 94.1-96.6 % to the type strains of the other Jannaschia species. Strain JSSK-16T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c, 11-methyl C18 : 1ω7c and C18 : 0 as the major fatty acids. The major polar lipids detected in strain JSSK-16T were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content of strain JSSK-16T was 68.8 mol% and its DNA-DNA relatedness values with the type strains of J. donghaensis and J. faecimaris were 18 and 12, respectively. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain JSSK-16T is separated from recognized species of the genus Jannaschia. On the basis of the data presented, strain JSSK-16T is considered to represent a novel species of the genus Jannaschia, for which the name Jannaschia confluentis sp. nov. is proposed. The type strain is JSSK-16T (=KACC 19436T=KCTC 62137T=NBRC 113018T).

Thalassotalea insulae sp. nov., isolated from tidal flat sediment.

A Gram-stain-negative, aerobic, motile and rod-shaped or ovoid bacterial strain, designated JDTF-40T, was isolated from a tidal flat in Jindo, an island of the Republic of South Korea. Strain JDTF-40T grew optimally at pH 7.0-8.0, at 30 °C and in the presence of 2 % (w/v) NaCl. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain JDTF-40T fell within the cluster comprising the type strains of Thalassotalea species. Strain JDTF-40T exhibited 16S rRNA gene sequence similarity values of 93.8-95.7 % to the type strains of Thalassotalea species. Strain JDTF-40T contained Q-8 as the predominant ubiquinone and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0 as the major fatty acids. The major polar lipids of strain JDTF-40T were phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid, one unidentified glycolipid and three unidentified lipids. The DNA G+C content of strain JDTF-40T was 41.3 mol%. Differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain JDTF-40T is distinct from recognized species of the genus Thalassotalea. On the basis of the data presented here, strain JDTF-40T is considered to represent a novel species of the genus Thalassotalea, for which the name Thalassotalea insulae sp. nov. is proposed. The type strain is JDTF-40T (=KACC 19433T=KCTC 62186T=NBRC 113040T).

Aestuariibius insulae gen. nov., sp. nov., isolated from a tidal flat sediment.

A Gram-stain-negative, non-motile and ovoid or rod-shaped bacterial strain, DBTF-13T, which was isolated from a tidal flat sediment of the Yellow Sea in South Korea, was characterized taxonomically. Strain DBTF-13T grew optimally at 25-30 °C and pH 7.0-8.0, and in the presence of 2.0 % (w/v) NaCl. The phylogenetic trees based on 16S rRNA gene sequences revealed that strain DBTF-13T formed an evolutionary lineage independent of other genera, including the genera Pseudooctadecabacter and Octadecabacter. Strain DBTF-13T exhibited 16S rRNA gene sequence similarity values of 96.9 % to the type strain of Pseudooctadecabacter jejudonensis, and of 95.8-96.5 % to the type strains of Octadecabacter species. Strain DBTF-13T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and C16 : 0 as the major fatty acids. The major polar lipids of strain DBTF-13T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain DBTF-13T was 61.6 mol%. The chemotaxonomic data and other differential phenotypic properties made it reasonable to differentiate strain DBTF-13T from the genera Pseudooctadecabacter and Octadecabacter. On the basis of the data presented, strain DBTF-13T constitutes a new genus and species within the class Alphaproteobacteria, for which the name Aestuariibius insulae gen. nov., sp. nov. is proposed. The type strain is DBTF-13T (=KACC 19432T=NBRC 113038T).

Paracoccus alimentarius sp. nov., isolated from a Korean foodstuff, salted pollack.

A Gram-stain-negative, aerobic, non-motile and coccoid or ovoid bacterial strain, designated LB2T, was isolated from a Korean foodstuff, salted pollack. Strain LB2T grew optimally at 25-30 °C, at pH 7.0-8.0 and in the presence of 0-2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences showed that strain LB2T belonged to the genus Paracoccus, coherently clustering with the type strain of Paracoccus sulfuroxidans. Strain LB2T exhibited 16S rRNA gene sequence similarity values of 98.0 and 97.0 % to the type strains of P. sulfuroxidans and Paracoccus halophilus, respectively, and of less than 96.9 % to the type strains of other Paracoccus species. Strain LB2T contained Q-10 as the predominant ubiquinone. Major fatty acids of strain LB2T were cyclo C19 : 0ω8c, C18 : 1ω7c and C16 : 0 (when grown on MA) or C18 : 1ω7c and C16 : 0 (on TSA). The major polar lipids detected in strain LB2T were phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified aminolipid and one unidentified glycolipid. The DNA G+C content of strain LB2T was 61.4 mol% and its DNA-DNA relatedness values with the type strains of P. sulfuroxidans and P. halophilus were 26 and 18 %, respectively. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain LB2T is separated from recognized Paracoccus species. On the basis of the data presented, strain LB2T is considered to represent a novel species of the genus Paracoccus, for which the name Paracoccus alimentarius sp. nov. is proposed. The type strain is LB2T (=KCTC 62138T=NBRC 113023T).

Dokdonia ponticola sp. nov., A Carrageenan-Degrading Bacterium of the Family Flavobacteriaceae Isolated from Seawater.

A Gram-stain-negative, aerobic, non-motile, and carrageenan-degrading bacterial strain, designated OISW-17T, was isolated from seawater around Oido, an island of South Korea, and its taxonomic position was determined using a polyphasic study. Optimal growth of the novel strain occurred at 20-25 °C and in the presence of 2.0% (w/v) NaCl. Phylogenetic trees using 16S rRNA gene sequences showed that strain OISW-17T forms a cluster with the type strains of Dokdonia species. The novel strain exhibited 16S rRNA gene sequence similarities of 95.7-96.3% to the type strains of Dokdonia species and of < 93.4% to the type strains of the other recognized species. Menaquinone-6 (MK-6) was found as the predominant menaquinone and iso-C15:0, iso-C15:1 G, and iso-C17:0 3-OH were the major fatty acids. Phosphatidylethanolamine, one unidentified lipid, and one unidentified aminolipid were major polar lipids detected in strain OISW-17T. Strain OISW-17T had DNA G+C content of 39.7 mol%. The differential phenotypic characteristics, along with the phylogenetic data, made strain OISW-17T to be distinct from recognized species of the genus Dokdonia. On the basis of the data given, strain OISW-17T represents a novel species of the genus Dokdonia, for which the name Dokdonia ponticola sp. nov. is proposed. The type strain of the novel species is OISW-17T (= KACC 19437T = KCTC 62187T = CGMCC 1.16527T).

Loktanella acticola sp. nov., isolated from seawater.

A Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated OISW-6T, was isolated from seawater near Oido, a South Korean island, and subjected to a polyphasic taxonomic study. Strain OISW-6T grew optimally at 25 °C, at pH 7.0-8.0 and in the presence of 2.0-3.0 % (w/v) NaCl. The phylogenetic trees based on 16S rRNA gene sequences showed that strain OISW-6T fell within the clade comprising the type strains of Loktanella species. Strain OISW-6T exhibited 16S rRNA gene sequence similarity values of 97.0-98.9 % to Loktanellamaricola, Loktanellatamlensis, Loktanellarosea, Loktanellamaritima, Loktanellasediminilitoris and Loktanellalitorea, and of 94.0-96.3 % to the type strains of the other Loktanella species. Strain OISW-6T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the major fatty acid. The major polar lipids detected in strain OISW-6T were phosphatidylcholine, phosphatidylglycerol and one unidentified aminolipid. The DNA G+C content of strain OISW-6T was 57.3 mol% and its DNA-DNA relatedness values with the type strains of the six phylogenetically closely related Loktanella species were 8-25 %. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain OISW-6T is separated from recognized species of the genus Loktanella. On the basis of the data presented, strain OISW-6T is considered to represent a novel species of the genus Loktanella, for which the name Loktanellaacticola sp. nov. is proposed. The type strain is OISW-6T (=KCTC 52837T=NBRC 112781T).

Tenacibaculum aestuariivivum sp. nov., isolated from a tidal flat.

A Gram-stain-negative, aerobic, non-motile, non-spore-forming bacterial strain, designated JDTF-79T, was isolated from a tidal flat in Jindo, an island of South Korea, and subjected to a taxonomic study using a polyphasic approach. Strain JDTF-79T grew optimally at 25 °C and in the presence of 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences showed that strain JDTF-79T fell within the clade comprising the type strains of species of the genus Tenacibaculum, clustering with the type strains of Tenacibaculum dicentrarchi, Tenacibaculum ovolyticum, 'Tenacibaculum haliotis' and Tenacibaculum soleae. The novel strain exhibited highest 16S rRNA gene sequence similarity (98.3 %) to the type strain of T. dicentrarchi and sequence similarities of 93.5-96.9 % to the type strains of the other species of the genus Tenacibaculum. Strain JDTF-79T contained MK-6 as the predominant menaquinone and anteiso-C15 : 0, iso-C15 : 0 3-OH and iso-C15 : 0 as the major fatty acids. The major polar lipids of strain JDTF-79T were phosphatidylethanolamine, one unidentified lipid and one unidentified aminophospholipid. The DNA G+C content of strain JDTF-79T was 30.3 mol%. Strain JDTF-79T had a mean DNA-DNA relatedness value of 19 % with the type strain of T. dicentrarchi. The differential phenotypic properties, together with the phylogenetic and genetic data, revealed that strain JDTF-79T is separated from other recognized species of the genus Tenacibaculum. On the basis of the data presented, strain JDTF-79T is considered to represent a novel species of the genus Tenacibaculum, for which the name Tenacibaculum aestuariivivum sp. nov. is proposed. The type strain is JDTF-79T (=KCTC 52980T=NBRC 112903T).

Demequina litorisediminis sp. nov., isolated from a tidal flat, and emended description of the genus Demequina.

A Gram-stain-positive, facultatively anaerobic, non-spore-forming, non-flagellated and rod-shaped or ovoid bacterial strain, GHD-1T, was isolated from a tidal flat sediment on the Yellow Sea, South Korea. It grew optimally at 30 °C, at pH 6.5-8.0 and in the presence of 1.0-2.0 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain GHD-1T fell within the cluster comprising the type strains of species of the genus Demequina. Strain GHD-1T exhibited 16S rRNA gene sequence similarity values of 97.0-98.8 % to the type strains of Demequinaglobuliformis, D. salsinemoris, D. flava, D. sediminicola and D. activiva, and of 95.5-96.9 % to the type strains of the other species of the genus Demequina. The peptidoglycan type of strain GHD-1T is A4ß based on l-Orn-l-Ser-l-Asp. It contained DMK-9(H4) and DMK-8(H4) as the major menaquinones and anteiso-C15 : 0, C16 : 0, iso-C16 : 0 and anteiso-C17 : 0 as the major fatty acids. The major polar lipids were phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside and one unidentified glycolipid. The DNA G+C content of strain GHD-1T was 68.7 mol%, and its DNA-DNA relatedness values with the type strains of five phylogenetically related species of the genus Demequina were 13-29 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain GHD-1T is separated from other recognized species of the genus Demequina. On the basis of the data presented, strain GHD-1T is considered to represent a novel species of the genus Demequina, for which the name Demequina litorisediminis sp. nov. is proposed. The type strain is GHD-1T (=KCTC 52260T=NBRC 112299T).