Application of the filter plate microbial trap (FPMT), for cultivating thermophilic bacteria from thermal springs in Barguzin area, eastern Baikal, Russia.

Hot springs are regarded as treasury of valuable thermophiles. Like other bacteria, thermophiles are not easily cultivated using conventional culture methods. We used an advanced cultivation method, the filter plate microbial trap (FPMT), to isolate bacteria from thermal springs. In total, 184 isolates were obtained from five thermal springs using the FPMT and standard agar plate method, and their 16S rRNA gene sequences were analyzed. FPMT allowed us to obtain a culture collection that was larger, richer, and more novel than that obtained by standard cultivation. Seven novel species were obtained using the FPMT technique, whereas only one was isolated using a standard cultivation. We also found clear differences in the patterns of phylogenetic diversity and physiological properties between isolates from two cultivation methods. The results have encouraged us to apply the FPMT method in other extreme environments and offer further support for fostering the development of new cultivation methods.

Flavobacterium paronense sp. nov., isolated from freshwater of an artificial vegetated island.

A Gram-stain-negative, motile by gliding, yellow-pigmented bacterial strain, designated KNUS1T, was isolated from Lake Paro in Korea. The phylogenetic tree based on 16S rRNA gene sequences showed that strain KNUS1T formed a distinct lineage within the genus Flavobacterium. Strain KNUS1T was closely related to Flavobacterium cheonhonense ARSA-15T (96.8 %16S rRNA gene sequence similarity), Flavobacterium pectinovorum DSM 6368T (96.3 %) and Flavobacterium dankookense ARSA-19T (96.1 %). The major fatty acids of strain KNUS1T were iso-C15 : 0 and iso-C15 : 1 G. The major polyamine was sym-homospermidine. The major polar lipids of strain KNUS1T were phosphatidylethanolamine, five unidentified aminolipids and three unidentified polar lipids. The major respiratory'quinone was menaquinone 6 (MK-6). The DNA G+C content of strain KNUS1T was 34.2 mol%. On the basis of the evidence presented in this study, strain KNUS1T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium paronense sp. nov. is proposed. The type strain is KNUS1T ( = KACC 17692T = CECT 8460T).

Apoptosis of AGS human gastric adenocarcinoma cells by methanolic extract of Dictamnus.

BACKGROUND: The root bark of Dictamnus dasycarpus Turcz has traditionally been used in East Asia to treat skin diseases such as eczema, atopic dermatitis, and psoriasis. However, it has also been reported to exhibit an anti-proliferative effect on cancer cells. OBJECTIVE: To investigate the anti-cancer effects of a methanol extract of Dictamnus dasycarpus root bark (MEDD) on AGS cells (a human gastric adenocarcinoma cell-line). MATERIALS AND METHODS: An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium assay, a caspase activity assay, cell cycle analysis, mitochondrial membrane potential (MMP) measurements, and western blotting were used to investigate the anti-cancer effects of MEDD on AGS cells. RESULTS: Treatment with MEDD significantly and concentration-dependently inhibited AGS cell growth. MEDD treatment in AGS cells led to increased accumulation of apoptotic sub-G1 phase cells in a concentration-dependent manner. Also, MEDD reduced the expressions of pro-caspase-3, -8 and -9, and increased the active form of caspase-3. Furthermore, subsequent Western blotting revealed elevated levels of poly (ADP-ribose) polymerase protein. MEDD treatment reduced levels of MMP and anti-apoptotic Bcl-2 and Bcl-xL proteins. Pretreatment with SB203580 (a specific inhibitor of p38 mitogen-activated protein kinases), SP600125 (a potent inhibitor of C-Jun N-terminal kinases), or PD98059 (a potent inhibitor of extracellular signal-regulated kinases) did not modify the effects of MEDD treatment. However, pretreatment with LY294002 (a specific inhibitor of Akt) significantly enhanced MEDD-induced cell death. CONCLUSION: These results suggest that MEDD-mediated cell death is associated with the intrinsic apoptotic pathway and that inhibition of Akt signaling contributes to apoptosis induction by MEDD.

Emticicia aquatica sp. nov., a species of the family Cytophagaceae isolated from fresh water.

A Gram-staining-negative, non-gliding, orange-pigmented bacterial strain, designated HMF2925T, was isolated from fresh water in Korea. The phylogenetic tree based on 16S rRNA gene sequences showed that strain HMF2925T formed a distinct lineage within the genus Emticicia. Strain HMF2925T was closely related to Emticicia oligotrophica DSM 17448T (95.5 %) and Emticicia ginsengisoli Gsoil 085T (94.1 %). The major fatty acids of strain HMF2925T were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), iso-C15 : 0, C16 : 1ω5c and C16 : 0.The major polar lipids of strain HMF2925T were phosphatidylethanolamine, phosphatidylinositol, diphosphatidylglycerol, phosphatidylglycerol, an unidentified glycolipid, two unidentified amino lipids and three unidentified polar lipids. The DNA G+C content of strain HMF2925T was 36.5 mol%. On the basis of the evidence presented in this study, strain HMF2925T represents a novel species of the genus Emticicia, for which the name Emticicia aquatica sp. nov. is proposed. The type strain is HMF2925T ( = KCTC 42574T = CECT 8858T).

Effects of Dangkwisoo­san, a traditional herbal medicine for treating pain and blood stagnation, on the pacemaker activities of cultured interstitial cells of Cajal.

The interstitial cells of Cajal (ICCs) are the pacemaker cells in the gastrointestinal (GI) tract. In the present study, the effects of Dangkwisoo­san (DS) on pacemaker potentials in cultured ICCs from the small intestine of the mouse were investigated. The whole­cell patch­clamp configuration was used to record pacemaker potentials from cultured ICCs and the increase in intracellular Ca2+ concentration ([Ca2+i) was analyzed in cultured ICCs using fura­2­acetoxymethyl ester. The generation of pacemaker potentials in the ICCs was observed. DS produced pacemaker depolarizations in a concentration dependent manner in current clamp mode. The 4­diphenylacetoxy­N­methyl­piperidine methiodide muscarinic M3 receptor antagonist inhibited DS­induced pacemaker depolarizations, whereas methoctramine, a muscarinic M2 receptor antagonist, did not. When guanosine 5'­[ß­thio] diphosphate (GDP­ß­S; 1 mM) was in the pipette solution, DS marginally induced pacemaker depolarizations, whereas low Na+ solution externally eliminated the generation of pacemaker potentials and inhibited the DS­induced pacemaker depolarizations. Additionally, the nonselective cation channel blocker, flufenamic acid, inhibited the DS­induced pacemaker depolarizations. Pretreatment with Ca2+­free solution and thapsigargin, a Ca2+­ATPase inhibitor in the endoplasmic reticulum, also eliminated the generation of pacemaker currents and suppressed the DS­induced pacemaker depolarizations. In addition, [Ca2+]i analysis revealed that DS increased [Ca2+]i. These results suggested that DS modulates pacemaker potentials through muscarinic M3 receptor activation in ICCs by G protein­dependent external and internal Ca2+ regulation and external Na+. Therefore, DS were observed to affect intestinal motility through ICCs.

Association of a Methanol Extract of Rheum undulatum L. Mediated Cell Death in AGS Cells with an Intrinsic Apoptotic Pathway.

OBJECTIVES: Rheum undulatum L. has traditionally been used for the treatment of many diseases in Asia. However, its anti-proliferative activity in cancer has still not been studied. In the present study, we investigated the anti-cancer effects of methanol extract of Rheum undulatum L. (MERL) on human adenocarcinoma gastric cell lines (AGS). METHODS: To investigate the anti-cancer effect of MERL on AGS cells, we treated the AGS cells with varying con¬centrations of MERL and performed 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays. Cell cycle analyses, measurements of the mitochondrial membrane potential (MMP), caspase activity assays and Western blots were conducted to determine whether AGS cell death occurred by apoptosis. RESULTS: Treatment with MERL significantly inhibited growth of AGS cells in a concentration dependent manner. MERL treatment in AGS cells leaded to increased accumulation of apoptotic sub G1 phase cells in a concentration dependent manner. In control cultures, 5.38% of the cells were in the sub G1 phase. In MERL treated cells, however, this percentage was significantly increased (9.95% at 70 µg/mL, 15.94% at 140 µg/mL, 26.56% at 210 µg/mL and 38.08% at 280 µg/mL). MERL treatment induced the decreased expression of pro-caspase-8 and -9 in a concentration dependent manner, whereas the expression of the active form of caspase-3 was increased. A subsequent Western blot analysis revealed increased cleaved levels of poly (ADP-ribose) polymerase (PARP) protein. Also, treatment with MERL increased the activities of caspase-3 and -9 compared with the control. MERL treatment increased the levels of the pro-apoptotic truncated Bid (tBid) and Bcl2 Antagonist X (Bax) proteins and decreased the levels of the anti-apoptotic B-cell lymphoma 2 (Bcl-2) protein, whose is the stabilization of mitochondria. However, inhibitions of p38, extracellular signal regulated kinases (ERKs) and C-Jun N-terminal kinases (JNK) by MERL treatment did not affect cell death. CONCLUSION: These results suggest that MERL mediated cell death is associated with an intrinsic apoptotic pathway in AGS cells.

Effects of Schisandra chinensis extract on gastrointestinal motility in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Schisandra chinensis (Turcz.) Baill. (SC) continues to be used as a traditional folk medicine in Asia, especially for the treatment of gastrointestinal (GI) disorders related to gastritis, diarrhea, enterocolitis and abnormal GI motility. AIM OF THE STUDY: Because GI disorders, especially abnormal GI motility, are major lifelong problems, we investigated the effects of SC on the pacemaker activity of the interstitial cells of Cajal (ICCs) in murine small intestine and GI motility. MATERIALS AND METHODS: Enzymatic digestions were used to dissociate ICCs from small intestines, and the whole-cell patch-clamp configuration was used to record potentials generated by cultured ICCs. In vivo effects of SC on GI motility were investigated by measuring the intestinal transit rate (ITR) of Evans blue in normal and GI motility dysfunction mice. RESULTS: SC extracts depolarized the membrane potentials of ICCs in a dose dependent manner. Pretreatment with Ca(2+) free solution or thapsigargin (a Ca(2+)-ATPase inhibitor in the endoplasmic reticulum) abolished the generation of pacemaker potentials by ICCs, and under these conditions, SC extract did not depolarize the membrane potentials of ICCs. In addition, membrane depolarizations were inhibited by intracellular GDPßS and by U-73122 (an active phospholipase C (PLC) inhibitor). In normal mice, ITRs were significantly increased by SC extract (0.1-1g/kg, intragastrically (i.g.)) in a dose dependent manner. Also, SC extract significantly recovered the GI motility dysfunctions in acetic acid (AA)-injected and streptozotocin (STZ)-induced diabetic mice, which are the GI motility animal models. MATERIALS AND METHODS: SC extract modulates pacemaker potentials in ICCs in a dose dependent manner via external and internal Ca(2+) regulations, and via G protein and the PLC pathway. In addition, SC extract increased ITRs in normal and abnormal GI motility mice models. This study shows that SC extract offers a basis for the development of a prokinetic agent that prevents or alleviates GI motility dysfunctions.

Highly heterogeneous soil bacterial communities around Terra Nova Bay of Northern Victoria Land, Antarctica.

Given the diminished role of biotic interactions in soils of continental Antarctica, abiotic factors are believed to play a dominant role in structuring of microbial communities. However, many ice-free regions remain unexplored, and it is unclear which environmental gradients are primarily responsible for the variations among bacterial communities. In this study, we investigated the soil bacterial community around Terra Nova Bay of Victoria Land by pyrosequencing and determined which environmental variables govern the bacterial community structure at the local scale. Six bacterial phyla, Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, Cyanobacteria, and Bacteroidetes, were dominant, but their relative abundance varied greatly across locations. Bacterial community structures were affected little by spatial distance, but structured more strongly by site, which was in accordance with the soil physicochemical compositions. At both the phylum and species levels, bacterial community structure was explained primarily by pH and water content, while certain earth elements and trace metals also played important roles in shaping community variation. The higher heterogeneity of the bacterial community structure found at this site indicates how soil bacterial communities have adapted to different compositions of edaphic variables under extreme environmental conditions. Taken together, these findings greatly advance our understanding of the adaption of soil bacterial populations to this harsh environment.

Effects of traditional Chinese herbal medicine San-Huang-Xie-Xin-Tang on gastrointestinal motility in mice.

AIM: To investigate the effects of San-Huang-Xie-Xin-Tang (SHXXT), a herbal product used in traditional Chinese medicine, on gastrointestinal (GI) motility in mice. METHODS: The in vivo effects of SHXXT on GI motility were investigated by measuring the intestinal transit rates (ITRs) using Evans blue in normal mice and in mice with experimentally induced GI motility dysfunction (GMD). RESULTS: In normal ICR mice, ITRs were significantly and dose-dependently increased by SHXXT (0.1-1 g/kg). GMD was induced by injecting acetic acid or streptozotocin intraperitoneally. The ITRs of GMD mice were significantly reduced compared to normal mice, and these reductions were significantly and dose-dependently inhibited by SHXXT (0.1-1 g/kg). CONCLUSION: These results suggest that SHXXT is a novel candidate for the development of a prokinetic agent that may prevent or alleviate GMD.

Ginsenoside Re inhibits pacemaker potentials via adenosine triphosphate-sensitive potassium channels and the cyclic guanosine monophosphate/nitric oxide-dependent pathway in cultured interstitial cells of Cajal from mouse small intestine.

BACKGROUND: Ginseng belongs to the genus Panax. Its main active ingredients are the ginsenosides. Interstitial cells of Cajal (ICCs) are the pacemaker cells of the gastrointestinal (GI) tract. To understand the effects of ginsenoside Re (GRe) on GI motility, the authors investigated its effects on the pacemaker activity of ICCs of the murine small intestine. METHODS: Interstitial cells of Cajal were dissociated from mouse small intestines by enzymatic digestion. The whole-cell patch clamp configuration was used to record pacemaker potentials in cultured ICCs. Changes in cyclic guanosine monophosphate (cGMP) content induced by GRe were investigated. RESULTS: Ginsenoside Re (20-40µM) decreased the amplitude and frequency of ICC pacemaker activity in a concentration-dependent manner. This action was blocked by guanosine 5'-[ß-thio]diphosphate [a guanosine-5'-triphosphate (GTP)-binding protein inhibitor] and by glibenclamide [an adenosine triphosphate (ATP)-sensitive K(+) channel blocker]. To study the GRe-induced signaling pathway in ICCs, the effects of 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (a guanylate cyclase inhibitor) and RP-8-CPT-cGMPS (a protein kinase G inhibitor) were examined. Both inhibitors blocked the inhibitory effect of GRe on ICC pacemaker activity. L-NG-nitroarginine methyl ester (100µM), which is a nonselective nitric oxide synthase (NOS) inhibitor, blocked the effects of GRe on ICC pacemaker activity and GRe-stimulated cGMP production in ICCs. CONCLUSION: In cultured murine ICCs, GRe inhibits the pacemaker activity of ICCs via the ATP-sensitive potassium (K(+)) channel and the cGMP/NO-dependent pathway. Ginsenoside Re may be a basis for developing novel spasmolytic agents to prevent or alleviate GI motility dysfunction.

Application of a new cultivation technology, I-tip, for studying microbial diversity in freshwater sponges of Lake Baikal, Russia.

One of the fundamental methods for cultivating bacterial strains is conventional plating on solid media, but this method does not reveal the true diversity of the bacterial community. In this study, we develop a new technique and introduce a new device we term, I-tip. The I-tip was developed as an in situ cultivation device that allows microorganisms to enter and natural chemical compounds to diffuse, thereby permitting the microorganisms to grow utilizing chemical compounds in their natural environment. The new method was used to cultivate microorganisms from Baikalian sponges, and the results were compared with conventional plating as well as a pyrosequencing-based molecular survey. The I-tip method produced cultures of 34 species from five major phyla, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, Firmicutes, and Gammaproteobacteria, 'missing' only two major phyla detected by pyrosequencing. Meanwhile, standard cultivation produced a smaller collection of 16 species from three major phyla, Betaproteobacteria, Firmicutes, and Gammaproteobacteria, failing to detect over half of the major phyla registered by pyrosequencing. We conclude that the I-tip method can narrow the gap between cultivated and uncultivated species, at least for some of the more challenging microbial communities such as those associated with animal hosts.

Lacihabitans soyangensis gen. nov., sp. nov., a new member of the family Cytophagaceae, isolated from a freshwater reservoir.

A Gram-staining-negative, non-motile and orange-pigmented bacterium, designated strain HME6675(T), was isolated from freshwater of a reservoir in Korea. The major fatty acids of strain HME6675(T) were iso-C15 : 0 (33.4 %) and summed feature 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c; 31.3 %). The major respiratory quinone was MK-7. The polar lipids were phosphatidylethanolamine, one unidentified aminolipid, one unidentified aminophospholipid and three unidentified polar lipids. The DNA G+C content of strain HME6675(T) was 37.7 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain HME6675(T) formed a lineage within the family Cytophagaceae and was related to Leadbetterella byssophila 4M15(T) (93.0 % sequence similarity), Fluviimonas pallidilutea TQQ6(T) (90.6 %) and Emticicia oligotrophica GPTSA100-15(T) (89.1 %). On the basis of the evidence presented in this study, strain HME6675(T) represents a novel genus and species of the family Cytophagaceae, for which the name Lacihabitans soyangensis gen. nov., sp. nov. is proposed. The type strain of Lacihabitans soyangensis is HME6675(T) ( = KCTC 23259(T) = CECT 7826(T)).

Mucilaginibacter soyangensis sp. nov., isolated from a lake.

A non-motile, yellow-orange-pigmented bacterial strain, designated HME6664(T), was isolated from Lake Soyang, Republic of Korea. The major fatty acids of strain HME6664(T) were summed feature 3 (comprising C16 : 1ω6c and/or C(16 : 1)ω7c; 44.7%) and iso-C15 : 0 (20.2%). The DNA G+C content was 40.8 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain HME6664(T) formed a lineage within the genus Mucilaginibacter. Strain HME6664(T) was closely related to Mucilaginibacter ximonensis (96.7%), Mucilaginibacter dorajii (96.5%) and Mucilaginibacter lappiensis (96.3%). On the basis of the evidence presented in this study, strain HME6664(T) represents a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter soyangensis sp. nov., is proposed. The type strain is HME6664(T) ( = KCTC 23261(T) = CECT 7824(T)).

Nationwide surveillance for pathogenic microorganisms in groundwater near carcass burials constructed in South Korea in 2010.

Widespread outbreaks of foot-and-mouth disease and avian influenza occurred in South Korea during 2010. In response to the culling of many animals to attenuate the spread of disease, South Korea used mass burial sites to dispose of the large number of carcasses; consequently, concerns about groundwater contamination by leachate from these burial sites are increasing. Groundwater is one of the main sources of drinking water, and its cleanliness is directly related to public health. Thus, this study aimed to evaluate the safety of groundwater around the burial sites (total of 600 sites). A total of 1,200 groundwater samples were collected though the country, and microbial analysis was conducted during two time periods: during the spring (n = 600; April to June 2012) and after rainfall (n = 600; August to October, 2012; fall). Fecal coliform and Escherichia coli were detected in 173 (14.4%) and 85 (7.1%) of the 1,200 samples, respectively. Salmonella spp. and Shigella spp. each were detected only once (0.083%). Clostridium perfringens was detected from 7 groundwater samples (0.583%), and E. coli O157:H7 was not detected. With respect to norovirus, only the GII type was detected from six groundwater samples (0.5%), and enterovirus was detected in 15 groundwater samples (1.25%). The frequency of E. coli that we detected was lower than that found in previous studies conducted in South Korea, but we detected higher frequency of fecal coliform than that observed in a previous report. The contamination frequencies of Salmonella spp. and Shigella spp. were very low, but C. perfringens, which could be an indicator of fecal pollution, was detected in seven regions. Overall, the results of the present study indicate a low possibility of contamination from burial sites. However, consistent monitoring is required to prevent microbial contamination of groundwater near the burial sites.

Installation of an artificial vegetating island in oligomesotrophic Lake Paro, Korea.

After cut off of inflowing water, Lake Paro, an oligomesotrophic lake lost littoral zone, an important region for the aquatic ecosystem. For the first step of restoration, the artificial vegetation island was installed. The concentration of nutrients in lake water was not sufficient for the growth of macrophyte as total phosphate was ranged from 58 to 83 µg L(-1). In order to overcome this problem, the hydrophobic substratum for bacterial attachment was selected as buoyant mat material of the artificial vegetation island. In this medium, total phosphate and total nitrogen were ranged from 190 to 1,060 µg L(-1) and from 4.9 to 9.1 mg L(-1), respectively. These concentrations were high enough for macrophytes growth. After launching 1,800 m(2) of AVI in Lake Paro, the macrophytes, Iris pseudoacorus and Iris ensata, grew well after five years of launching without the addition of fertilizer. Furthermore, fishes were plentiful under the artificial vegetation island, and ducks were observed on the artificial vegetation island. Bacteria using sunlight as energy source and self-designed ecotechnology can be used as an alternative method for the restoration of disturbed littoral zone in oligo-mesotrophic lakes.

Stratified distribution of nutrients and extremophile biota within freshwater ice covering the surface of Lake Baikal.

Biological entities and gradients of selected chemicals within the seemingly barren ice layers covering Lake Baikal were investigated. Ice cores 40-68 cm long were obtained from in shore and offshore sites of Southern Lake Baikal during the cold period of a year (March-April) in 2007 and 2008. In microscopic observations of the melted ice, both algae and bacteria were found in considerable numbers (>10(3) cells/L and >10(4) cells/ml, respectively). Among all organisms found, diatom was generally the most predominant taxon in the ice. Interestingly, both planktonic and benthic algae were present in considerable numbers (2-4×10(4) cells/L). Dominant phototrophic picoplankton were comprised of small green algae of various taxa and cyanobacteria of Synechococcus and Cyanobium. The bacterial community consisted mostly of short rod and cocci cells, either free-living or aggregated. Large numbers of yeast-like cells and actinomycete mycelium were also observed. Concentrations of silica, phosphorus, and nitrate were low by an order of magnitude where biota was abundant. The profile of the ice could be interpreted as vertical stratification of nutrients and biomass due to biological activities. Therefore, the organisms in the ice were regarded to maintain high activity while thriving under freezing conditions. Based on the results, it was concluded that the freshwater ice covering the surface of Lake Baikal is considerably populated by extremophilic microorganisms that actively metabolize and form a detritus food chain in the unique large freshwater ecosystem of Lake Baikal.

Flavobacterium yonginense sp. nov. and Flavobacterium myungsuense sp. nov., isolated from a mesotrophic artificial lake.

Two non-motile, Gram-staining-negative, yellow-pigmented bacterial strains designated HMD1001T and HMD1033T were isolated from the water of a mesotrophic artificial lake in Korea. A phylogenetic tree based on 16S rRNA gene sequences indicated that both strains could be assigned to the genus Flavobacterium; strain HMD1001T appeared most closely related to Flavobacterium fluvii H7T (96.8 % sequence similarity), F. succinicans DSM 4002T (96.6 %) and F. hydatis DSM 2063T (96.6 %) whereas strain HMD1033T appeared most closely related to Flavobacterium psychrolimnae LMG 2201T (96.2 %), F. segetis AT1048T (96.2 %) and F. weaverense AT1042T (96.2 %). The major fatty acids of strain HMD1001T were iso-C15:0 (21.5 %), summed feature 3 (comprising C16:1ω6c and/or C16:1ω7c; 18.0 %) and iso-C15:1 G (7.6 %), whereas those of HMD1033T were summed feature 3 (23.8 %), iso-C15:0 3-OH (16.9 %), iso-C15:0 (15.3 %) and anteiso-C15:0 (12.1 %). The genomic DNA G+C contents of strains HMD1001T and HMD1033T were 35.9 and 32.2 mol%, respectively. Phylogenetic and phenotypic evidence indicates that strains HMD1001T and HMD1033T represent two novel species of the genus Flavobacterium, for which the names Flavobacterium yonginense sp. nov. (type strain HMD1001T=KCTC 22796T=CECT 7594T) and Flavobacterium myungsuense sp. nov. (type strain HMD1033T=KCTC 22825T=CECT 7649T) are proposed.

Gramella jeungdoensis sp. nov., isolated from a solar saltern in Korea.

A non-motile, Gram-stain-negative, yellow pigmented, rod-shaped bacterium, strain HMD3159(T), was isolated from a solar saltern in Korea. The major fatty acids were iso-C(15:0) (26.3%), iso-C(17:0) 3OH (12.1%), iso-C(16:0) (12.0%), summed feature 3 (comprising C(16:1) ω7c and/or C(16:1) ω6c; 11.0%) and summed feature 9 (iso-C17:1 ω9c and/or 10-methyl C(16:0); 10.0%). The major respiratory quinone was MK-6. The DNA G+C content was 40.9 mol%. The phylogenetic tree based on 16S rRNA gene sequences showed that strain HMD3159(T) formed a lineage within the genus Gramella and closely related to Gramella gaetbulicola (95.5% sequence similarity), Gramella portivictoriae (94.9%), Gramella echinicola (94.6%), and Gramella marina (93.6%). On the basis of the evidence presented in this study, strain HMD3159(T) represents a novel species of the genus Gramella, for which the name Gramella jeungdoensis sp. nov., is proposed. The type strain is HMD3159(T) (=KCTC 32123(T) =CECT 7683(T)).

Ecological development and genetic diversity of Microcystis aeruginosa from artificial reservoir in Russia.

Microcystis aeruginosa is a well-known Cyanobacterium responsible for the formation of toxic water blooms around the world. Shallow, warm, and eutrophic reservoirs provide the most favourable conditions for M. aeruginosa development. Numerous studies have been devoted to this species, but there still is a necessity to develop additional approaches for the monitoring of cyanobacteria in reservoirs. In this study, M. aeruginosa in the water column of a hypereutrophic Siberian reservoir was investigated by fluorescence, light, and electron microscopy as well as genetic analysis using a mcyE marker. Here, we demonstrate the genetic diversity and features of the fluorescence spectra for different ecotypes of this species. We suggest that a fluorescence approach can be used to identify M. aeruginosa in a natural environment in order to increase the effectiveness of ecological monitoring and water quality evaluation.

Pontibacter salisaro sp. nov., isolated from a clay tablet solar saltern in Korea.

A Gram-negative, aerobic, rod-shaped, and red-pigmented bacterial strain, HMC5104(T), was isolated from a solar saltern, found in Jeungdo, Republic of Korea (34°59'47″N 126°10'02″E). The major fatty acids were summed feature 4 (comprising iso-C(17:1) I and/or anteiso-C(17:1) B; 37.2%), iso-C(15:0) (20.4%), and iso-C(17.0) 30H (15.3%). The DNA G+C content was 46.0 mol%. The major isoprenoid quinone was menaquinone-7 (MK-7). A phylogenetic tree based on 16S rRNA gene sequences showed that strain HMC5104(T) formed a lineage within the genus Pontibacter, and was closely related to Pontibacter korlensis (95.9%), P. roseus (94.9%), and P. actiniarum (94.3%). Similarities to all other Pontibacter species were between 95.9-93.9%. On the basis of the evidence presented in this study, strain HMC5104(T) represents a novel species of the genus Pontibacter, for which the name Pontibacter salisaro sp. nov. is proposed. The type strain is HMC5104(T) (=KCTC 22712(T) = NBRC 105731(T)).