Simiduia aestuariiviva sp. nov., a gammaproteobacterium isolated from a tidal flat sediment

A Gram-stain negative, aerobic, motile and rod-shaped bacterial strain, designated J-MY2^T, was isolated from a tidal flat sediment of the South Sea, South Korea. Strain J-MY2^T was found to grow optimally at 30 °C, at pH 7.0–8.0 and in the presence of 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain J-MY2^T forms a cluster with the type strains of Simiduia species. Strain J-MY2^T exhibited 16S rRNA gene sequence similarity values of 97.62–98.77 % to the type strains of four Simiduia species and of <92.95 % sequence similarity to the type strains of the other recognized species. Strain J-MY2^T was found to contain Q-8 as the predominant ubiquinone and summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c), C_16:0, C_18:1 ω7c and C_17:1 ω8c as the major fatty acids. The major polar lipids of strain J-MY2^T were identified as phosphatidylethanolamine, phosphatidylglycerol, three unidentified glycolipids and one unidentified lipid. The DNA G+C content of strain J-MY2^T was determined to be 54.8 mol% and its mean DNA–DNA relatedness values with the type strains of the four Simiduia species were in the range 21–34 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain J-MY2^T is separated from other Simiduia species. On the basis of the data presented, strain J-MY2^T is considered to represent a novel species of the genus Simiduia, for which the name Simiduia aestuariiviva sp. nov. is proposed. The type strain is J-MY2^T ( = KCTC 42073^T = CECT 8571^T).     

Shewanella litorisediminis sp. nov., a gammaproteobacterium isolated from a tidal flat sediment

A Gram-negative, facultatively anaerobic, non-motile and rod-shaped bacterial strain, designated SMK1-12^T, was isolated from a tidal flat sediment on the western coast of Korea. Phylogenetic analyses based on 16S rRNA and gyrB gene sequences showed that strain SMK1-12^T belonged to the genus Shewanella, clustering with the type strain of Shewanella amazonensis. Strain SMK1-12^T exhibited the highest 16S rRNA gene sequence similarity value (97.0 %) and the highest gyrB sequence similarity value (87.8 %) to S. amazonensis SB2B^T, respectively. Strain SMK1-12^T contained simultaneously both menaquinones and ubiquinones; the predominant menaquinone was MK-7 and the predominant ubiquinones were Q-7 and Q-8. The major fatty acids (>10 % of the total fatty acids) detected in strain SMK1-12^T were the MIDI system summed feature 3 (iso-C_15:0 2-OH and/or C_16:1 ω7c), iso-C_15:0, C_17:1 ω8c and C_16:0. The DNA G+C content of strain SMK1-12^T was 58.0 mol% and its mean DNA–DNA relatedness value with S. amazonensis ATCC 700329^T was 15 ± 4.6 %. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain SMK1-12^T is distinguishable from recognized Shewanella species. On the basis of the data presented, strain SMK1-12^T is considered to represent a novel Shewanella species, for which the name Shewanella litorisediminis sp. nov. is proposed. The type strain is SMK1-12^T (=KCTC 23961^T = CCUG 62411^T).     

Pelagicola litorisediminis sp. nov., a novel alphaproteobacterium isolated from tidal flat sediment

A Gram-negative, aerobic, non-motile and rod-shaped or ovoid bacterial strain, designated D1-W8^T, was isolated from a tidal flat on the South Sea in South Korea. Strain D1-W8^T was found to grow optimally at 25 °C, at pH 7.0–8.0 and in the presence of 2.0–3.0 % (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain D1-W8^T clustered with the type strain of Pelagicola litoralis showing 97.1 % sequence identity. 16S rRNA gene sequences of the type strains of other species exhibited lower similarity values. Strain D1-W8^T was determined to contain Q-10 as the predominant ubiquinone and C_18:1 ω7c as the predominant fatty acid. The major polar lipids of strain D1-W8^T were identified as phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain D1-W8^T was determined to be 57.9 mol% and its DNA–DNA relatedness value with the type strain of P. litoralis was 17 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain D1-W8^T is separate from P. litoralis. On the basis of the data presented, strain D1-W8^T is considered to represent a novel species of the genus Pelagicola, for which the name Pelagicola litorisediminis sp. nov. is proposed. The type strain is D1-W8^T (= KCTC 32327^T = CECT 8287^T).     

Aestuariihabitans beolgyonensis gen. nov., sp. nov., a novel alphaproteobacterium isolated from tidal flat sediment

A Gram-negative, non-motile and rod-shaped bacterial strain, designated BB-MW15^T, was isolated from a tidal flat of the southern coast of the Korean peninsula, and its taxonomic position was investigated by using a polyphasic taxonomic approach. Strain BB-MW15^T grew optimally at 30 °C, at pH 7.0–8.0 and in the presence of 2–3 % (w/v) NaCl. Strain BB-MW15^T exhibited the highest 16S rRNA gene sequence similarity values to the type strains of Marivita byunsanensis (96.8 %), Thalassobius maritimus (96.6 %), Sulfitobacter marinus (96.4 %) and Marinovum algicola (96.3 %). Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain BB-MW15^T forms an independent lineage within the evolutionary radiation encompassed by the Roseobacter clade of the class Alphaproteobacteria. Strain BB-MW15^T contained Q-10 as the predominant ubiquinone and C_18:1 ω7c as the predominant fatty acid. The major polar lipids detected in strain BB-MW15^T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain BB-MW15^T is 62.7 mol%. Based on phylogenetic, chemotaxonomic and other phenotypic characteristics, strain BB-MW15^T represents a new genus and a new species within Alphaproteobacteria, for which the name Aestuariihabitans beolgyonensis gen. nov., sp. nov. is proposed. The type strain of A. beolgyonensis is BB-MW15^T (= KCTC 32324^T = CCUG 63829^T).     

Roseovarius gaetbuli sp. nov., a novel alphaproteobacterium isolated from a tidal flat sediment

A Gram-negative, aerobic, non-motile and ovoid or rod-shaped bacterial strain, designated YM-20^T, was isolated from a tidal flat of the Yellow Sea in South Korea. Strain YM-20^T was found to grow optimally at 30 °C, at pH 7.0–8.0 and in the presence of 2.0–3.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain YM-20^T clustered consistently with the type strains of ‘Roseovarius marisflavi’ and Roseovarius lutimaris, with which it exhibited 16S rRNA gene sequence similarities of 99.86 and 98.71 %, respectively. Strain YM-20^T was found to contain Q-10 as the predominant ubiquinone and C_18:1 ω7c as the predominant fatty acid. The major polar lipids of strain YM-20^T were identified as phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain YM-20^T was determined to be 60.9 mol% and its DNA–DNA relatedness values with the type strains of ‘R. marisflavi’, R. lutimaris and Pelagicola litorisediminis were 53 ± 7.1, 22 ± 5.5 and 13 ± 4.7  %, respectively. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain YM-20^T is separated from ‘R. marisflavi’, R. lutimaris, the other Roseovarius species and P. litorisediminis. On the basis of the data presented, strain YM-20^T is considered to represent a novel species of the genus Roseovarius, for which the name Roseovarius gaetbuli sp. nov. is proposed. The type strain is YM-20^T (= KCTC 32428^T = CECT 8370^T).     

Shewanella seohaensis sp. nov., isolated from a tidal flat sediment

A Gram-negative, motile and rod-shaped bacterial strain, designated S7-3^T, was isolated from a tidal flat sediment at Saemankum on the western coast of Korea. Phylogenetic analyses based on 16S rRNA gene and gyrB sequences showed that strain S7-3^T belonged to the genus Shewanella, clustering with Shewanella decolorationis S12^T. Strain S7-3^T exhibited 98.8 % 16S rRNA gene sequence similarity and 96.8 % gyrB sequence similarity to S. decolorationis S12^T, respectively. The 16S rRNA gene sequence similarity values between strain S7-3^T and other members of the genus Shewanella were in the range of 93.0–98.0 %. Strain S7-3^T contained simultaneously both menaquinones (MK) and ubiquinones (Q); the predominant menaquinone was MK-7 and the predominant ubiquinones were Q-7 and Q-8. The fatty acid profiles of strain S7-3^T and S. decolorationis JCM 21555^T were similar; major components were C_17:1 ω8c, iso-C_15:0 and iso-C_15:0 2-OH and/or C_16:1 ω7c. The DNA G+C content of strain S7-3^T was 51.8 mol% and its mean DNA–DNA relatedness value with S. decolorationis JCM 21555^T was 43 %. Differential phenotypic properties of strain S7-3^T, together with the phylogenetic and genetic distinctiveness, revealed that this strain is distinguishable from recognized Shewanella species. On the basis of the data presented, strain S7-3^T is considered to represent a novel Shewanella species, for which the name Shewanella seohaensis sp. nov. is proposed. The type strain is S7-3^T (=KCTC 23556^T = CCUG 60900^T).     

Thalassobius aestuarii sp. nov., isolated from tidal flat sediment

A strictly aerobic, non-motile, ovoid-shaped Alphaproteobacteria, designated strain JC2049(T), was isolated from a tidal flat sediment sample. The results of 16S rRNA gene sequence analysis indicated that this isolate belonged to the genus Thalassobius, with a sequence similarity of 96.9-97.3% to other valid Thalassobius spp. The cells required 1-7% NaCl for growth (optimum 2%) and accumulated poly-beta-hydroxybutyrate. Nitrite was reduced to nitrogen, but nitrate was not reduced to nitrite. No genetic potential for aerobic anoxygenic photosynthesis was detected. The primary isoprenoid quinone (Ubiquinone-10), predominant cellular fatty acids (C(18:1)omega7c, 11 methyl C(18:1)omega7c and C(16:0)) and DNA G+C content (61 mol%) were all consistent with the assignment of this isolate to the genus Thalassobius. Several phenotypic characteristics clearly distinguished our isolate from other Thalassobius species. The degree of genomic relatedness between strain JC2049(T) and other Thalassobius species was in a range of 20-43%. The polyphasic data presented in this study indicates that our isolate should be classified as a novel species within the genus Thalassobius. The name Thalassobius aestuarii sp. nov. is therefore proposed for this isolate; the type strain is JC2049(T) (= IMSNU 14011(T) = KCTC 12049(T) = DSM 15283(T)).     

Bacillus gaemokensis sp. nov., isolated from foreshore tidal flat sediment from the Yellow Sea

A Gram-positive, rod-shaped, endospore-forming organism, strain BL3-6^T, was isolated from tidal flat sediments of the Yellow Sea in the region of Tae-An. A 16S rRNA gene sequence analysis demonstrated that this isolate belongs to the Bacillus cereus group, and is closely related to Bacillus mycoides (99.0% similarity), Bacillus thuringiensis (99.0%), Bacillus weihenstephanensis (99.0%), Bacillus cereus (98.9%), Bacillus anthracis (98.8%), and Bacillus pseudomycoides (98.1%). The phylogenetic distance from any validly described Bacillus species outside the Bacillus cereus group was less than 95.6%. The DNA G+C content of the strain was 39.4 mol% and the major respiratory quinone was menaquinone-7. The major cellular fatty acids were iso-C_14:0 (17.8%), iso-C_16:0 (15.8%), and iso-C_12:0 (11.3%). The diagnostic amino acid of the cell wall was meso-diaminopimelic acid and the major cell wall sugar was galactose. The results of DNA-DNA hybridization (<55.6%) and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain BL3-6^T from the published Bacillus species. BL3-6^T therefore represents a new species, for which the name Bacillus gaemokensis sp. nov. is proposed, with the type strain BL3-6^T (=KCTC 13318^T =JCM 15801^T).     

Tenacibaculum caenipelagi sp. nov., a member of the family Flavobacteriaceae isolated from tidal flat sediment

A Gram-stain-negative, non-spore-forming, aerobic, non-flagellated, gliding and rod-shaped bacterial strain, designated HJ-26M^T, was isolated from a tidal flat sediment in the Korean peninsula. It grew optimally at 25–30 °C, at pH 7.0–8.0 and in the presence of 2 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that the strain fell within the clade comprising Tenacibaculum species, clustering coherently with the type strains of Tenacibaculum lutimaris and Tenacibaculum aestuarii. Strain HJ-26M^T exhibited the highest 16S rRNA gene sequence similarity values of 98.4 and 98.2 % to T. lutimaris TF-26^T and T. aestuarii SMK-4^T, respectively, and of 94.9–97.4 % to the type strains of the other Tenacibaculum species. Strain HJ-26M^T contained MK-6 as the predominant menaquinone and iso-C_15:0 and iso-C_17:0 3-OH as the major fatty acids. The DNA G+C content of strain HJ-26M^T was 34.5 mol% and its mean DNA–DNA relatedness values with the type strains of T. lutimaris and T. aestuarii were 19 and 23 %, respectively. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain HJ-26M^T is separate from other Tenacibaculum species. On the basis of the data presented, strain HJ-26M^T is considered to represent a novel species of the genus Tenacibaculum, for which the name Tenacibaculum caenipelagi sp. nov. is proposed. The type strain is HJ-26M^T (= KCTC 32323^T = CECT 8283^T).     

Marinitalea sucinacia gen. nov., sp. nov., a marine bacterium of the family Flavobacteriaceae isolated from tidal flat sediment

An amber-pigmented, Gram-negative, rod-shaped and aerobic bacterial strain devoid of flagella, designated strain JC2131(T) , was isolated from tidal flat sediment of Dongmak in Ganghwa island, South Korea. Identification was carried out on the basis of polyphasic taxonomy. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the isolate belonged to the family Flavobacteriaceae and showed the highest sequence similarity of 94.5% with Lutibacter litoralis KCCM 42118(T). The predominant cellular fatty acids were iso-C(15:0) (25.9%), iso-C(15:0) 3-OH (20.0%) and iso-C(13:0) (12.7%). Flexirubin-type pigments were absent. The major isoprenoid quinone was MK-6. The DNA G+C content was 43.7 mol%. Several phenotypic and chemotaxonomic properties including growth at pH 6, sea salts requirement, aesculin hydrolysis, carbon utilization, DNA G+C content and fatty acid profiles also differentiated the strain from the related members of the family. Therefore, results from the polyphasic taxonomy study suggested that strain JC2131(T) represents a novel genus and species in the family Flavobacteriaceae for which the name Marinitalea sucinacia gen. nov., sp. nov. is proposed (type strain JC2131(T)=KCTC 12705(T)=JCM 14003(T)).     

Loktanella aestuariicola sp. nov., an alphaproteobacterium isolated from a tidal flat

A Gram-stain negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, J-TF4^T, which was isolated from a tidal flat in the South Sea of South Korea, was characterized taxonomically. Strain J-TF4^T was found to grow optimally at 30 °C, at pH 7.0–8.0 and in presence of 2.0–3.0 % (w/v) NaCl. In the neighbour-joining phylogenetic tree based on 16S rRNA gene sequences, strain J-TF4^T fell within the clade comprising the type strains of Loktanella species, clustering with the type strains of Loktanella cinnabarina, Loktanella hongkongensis, Loktanella soesokkakensis, Loktanella pyoseonensis and ‘Loktanella variabilis’ showing sequence similarity values of 97.2–98.4 %. The strain exhibited 16S rRNA gene sequence similarity values of 94.1–95.4 % to the type strains of the other Loktanella species. Strain J-TF4^T was found to have Q-10 as the predominant ubiquinone and C_18:1 ω7c as the major fatty acid. The major polar lipids of strain J-TF4^T were identified as phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified glycolipid and an unidentified aminolipid. The DNA G+C content of strain J-TF4^T was determined to be 67.9 mol% and its mean DNA–DNA relatedness values with the type strains of five phylogenetically related Loktanella species were 17.7–23.3 %. Differential phenotypic properties, together with the phylogenetic and genetic data, demonstrate that strain J-TF4^T is separated from other Loktanella species. On the basis of the data presented, strain J-TF4^T is considered to represent a novel species of the genus Loktanella, for which the name Loktanella aestuariicola sp. nov. is proposed. The type strain is J-TF4^T (=KCTC 42135^T=NBRC 110408^T).     

Salinimonas lutimaris sp. nov., a polysaccharide-degrading bacterium isolated from a tidal flat

A Gram-negative, non-motile, non-endospore-forming bacterial strain, designated DPSR-4^T, was isolated from a tidal flat sediment on the southern coast of Korea. Strain DPSR-4^T grew optimally at 25–30°C, at pH 7.0–7.5 and in the presence of 2% (w/v) NaCl. A Neighbour-Joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain DPSR-4^T clustered with Salinimonas chungwhensis BH030046^T by a high bootstrap resampling value of 99.7%. Strain DPSR-4^T exhibited 96.2% 16S rRNA gene sequence similarity to that of S. chungwhensis BH030046^T and 93.7–96.6% sequence similarity to the sequences of type strains of Alteromonas species. Strain DPSR-4^T contained Q-8 as the predominant ubiquinone and iso-C_15:0 2-OH and/or C_16:1 ω7c, C_16:0 and C_18:1 ω7c as the major fatty acids. The major polar lipids detected in strain DPSR-4^T and S. chungwhensis KCTC 12239^T were phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid. The DNA G+C content was 53.4 mol%. Differential phenotypic properties and phylogenetic distinctiveness of strain DPSR-4^T demonstrated that this strain is distinguishable from the sole recognized species of the genus Salinimonas, S. chungwhensis. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain DPSR-4^T is considered to represent a novel species of the genus Salinimonas, for which the name Salinimonas lutimaris sp. nov. is proposed. The type strain is DPSR-4^T (KCTC 23464^T, CCUG 60743^T).     

Colwellia meonggei sp. nov., a novel gammaproteobacterium isolated from sea squirt Halocynthia roretzi

A Gram-negative, non-spore-forming, aerobic, motile and rod-shaped or ovoid bacterial strain, designated MA1-3^T, was isolated from a sea squirt (Halocynthia roretzi) collected from the South sea in South Korea. Strain MA1-3^T was found to grow optimally at 25 °C, at pH 7.0–8.0 and in the presence of 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain MA1-3^T fell within the clade comprising Colwellia species, clustering coherently with the type strains of Colwellia aestuarii, Colwellia polaris and Colwellia chukchiensis, showing sequence similarity values of 97.2, 96.4 and 95.6 %, respectively. It exhibited 16S rRNA gene sequence similarity values of 93.9–96.1 % to the type strains of the other Colwellia species. Strain MA1-3^T was found to contain Q-8 as the predominant ubiquinone and C_16:1 ω7c and/or C_16:1 ω6c, C_16:0 and C_16:1 ω9c as the major fatty acids. The DNA G+C content of strain MA1-3^T was determined to be 39.1 mol% and its mean DNA–DNA relatedness value with the type strain of C. aestuarii was 13 ± 5.4 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that the novel strain is separated from other Colwellia species. On the basis of the data presented, strain MA1-3^T is considered to represent a novel species of the genus Colwellia, for which the name Colwellia meonggei sp. nov. is proposed. The type strain is MA1-3^T (=KCTC 32380^T = CECT 8302^T).     

Glaciecola aquimarina sp. nov., a gammaproteobacterium isolated from coastal seawater

A Gram-negative, aerobic, non-motile and ovoid or rod-shaped bacterial strain, GGW-M5^T, was isolated from seawater on the southern coast in Korea, and its taxonomic position was investigated by using a polyphasic approach. Strain GGW-M5^T grew optimally at pH 7.0–8.0, at 30 °C and in the presence of 2 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain GGW-M5^T belonged to the genus Glaciecola, joining the cluster comprising the type strains of G. agarilytica, G. arctica, G. chathamensis, G. mesophila, G. polaris and G. psychrophila, with which it exhibited 16S rRNA gene sequence similarity values of 95.9–96.7 %. Strain GGW-M5^T exhibited sequence similarity values of 93.2–94.8 % to the type strains of the other Glaciecola species. Strain GGW-M5^T contained Q-8 as the predominant ubiquinone and C_16:1 ω7c and/or iso-C_15:0 2-OH, C_16:0 and C_14:0 2-OH as the major fatty acids. Major polar lipids were phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. The DNA G+C content was 42.4 mol%. Differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain GGW-M5^T could be distinguished from other Glaciecola species. On the basis of the data presented, strain GGW-M5^T is considered to represent a novel species of the genus Glaciecola, for which the name Glaciecola aquimarina sp. nov. is proposed. The type strain is GGW-M5^T (=KCTC 32108^T = CCUG 62918^T).     

Spongiibacter pelagi sp. nov., a marine gammaproteobacterium isolated from coastal seawater

A novel gammaproteobacterium, designated as KMU-158^T, was isolated from seawater collected on the coastline of Dadaepo in the Republic of Korea, and characterized using a polyphasic taxonomic approach. Strain KMU-158^T was Gram-staining-negative, pale beige-colored, strictly aerobic, rod-shaped, motile, and chemoorganoheterotrophic. The novel isolate was able to grow at 0–3% NaCl concentrations (w/v), pH 6.5–9.5, and 15–40 °C. The analysis based on 16S rRNA gene sequences indicated that strain KMU-158^T belongs to the family Spongiibacteraceae and shared the highest similarity with Spongiibacter tropicus CL-CB221^T (96.1%). The major cellular fatty acids were summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c) and C_17:1 ω8c. The only respiratory quinone was identified as ubiquinone-8. The polar lipids of strain KMU-158^T contained phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and two unidentified lipids. The assembled draft genome size of strain KMU-158^T was 3.29 Mbp with a DNA G?+?C content of 51.3%. The average nucleotide identity, digital DNA–DNA hybridization, and average amino acid identity values of KMU-158^T and the representatives of the genus Spongiibacter were found to be 78.5–79.1%, 13.8–14.1%, and 66.6–66.8%, respectively. From the distinct phenotypic, phylogenetic, genomic, and chemotaxonomic properties, the strain KMU-158^T is considered to represent a novel species of the genus Spongiibacter, for which the name Spongiibacter pelagi sp. nov. is proposed. The type strain of the species S. pelagi sp. nov. is KMU-158^T (=?KCCM 90448^T?=?NBRC 114307^T).

     

Aceticlastic and NaCl-requiring methanogen "Methanosaeta pelagica" sp. nov., isolated from marine tidal flat sediment

Among methanogens, only 2 genera, Methanosaeta and Methanosarcina, are known to contribute to methanogenesis from acetate, and Methanosaeta is a specialist that uses acetate specifically. However, Methanosaeta strains so far have mainly been isolated from anaerobic digesters, despite the fact that it is widespread, not only in anaerobic methanogenic reactors and freshwater environments, but also in marine environments, based upon extensive 16S rRNA gene-cloning analyses. In this study, we isolated an aceticlastic methanogen, designated strain 03d30q(T), from a tidal flat sediment. Phylogenetic analyses based on 16S rRNA and mcrA genes revealed that the isolate belongs to the genus Methanosaeta. Unlike the other known Methanosaeta species, this isolate grows at Na(+) concentrations of 0.20 to 0.80 M, with an optimum concentration of 0.28 M. Quantitative estimation using real-time PCR detected the 16S rRNA gene of the genus Methanosaeta in the marine sediment, and relative abundance ranged from 3.9% to 11.8% of the total archaeal 16S rRNA genes. In addition, the number of Methanosaeta organisms increased with increasing depth and was much higher than that of Methanosarcina organisms, suggesting that aceticlastic methanogens contribute to acetate metabolism to a greater extent than previously thought in marine environments, where sulfate-reducing acetate oxidation prevails. This is the first report on marine Methanosaeta species, and based on phylogenetic and characteristic studies, the name "Methanosaeta pelagica" sp. nov. is proposed for this novel species, with type strain 03d30q.     

Bacillus manliponensis sp. nov., a new member of the Bacillus cereus group isolated from foreshore tidal flat sediment

A Gram-positive, endospore-forming, new Bacillus species, strain BL4-6^T, was isolated from tidal flat sediment of the Yellow Sea. Strain BL4-6^T is a straight rod, with motility by peritrichate flagella. The cell wall contains meso-diaminopimelic acid, and the major respiratory quinone is menaquinone-7. The major fatty acids are iso-C_15:0 and summed feature 3 (containing C_16:1 ω7c/iso-C_15:0 2OH, and/or iso-C_15:0 2OH/C_16:1 ω7c). Cells are catalase-positive and oxidase-negative. The G+C content of the genomic DNA is 38.0 mol%. Based on a comparative 16S rRNA gene sequence analysis, the isolate belongs to the genus Bacillus, forms a clade with the Bacillus cereus group, and is closely related to Bacillus mycoides (98.5%), Bacillus cereus (98.5%), Bacillus anthracis (98.4%), Bacillus thuringiensis (98.4%), Bacillus weihenstephanensis (98.1%), and Bacillus pseudomycoides (97.5%). The isolate showed less than 85% similarity of the gyrA gene sequence and below 95% similarity of the rpoB gene sequence to the members of this group. DNA-DNA relatedness between strain BL4-6^T and B. cereus group was found to be in a range of 22.8–42.3%, and thus BL4-6^T represents a unique species. On the basis of these studies, strain BL4-6^T (=KCTC 13319^T =JCM 15802^T) is proposed to represent the type strain of a novel species, Bacillus manliponensis sp. nov.     

<Emphasis Type="Italic">Aliihoeflea aestuarii</Emphasis> gen. nov., sp. nov., a novel bacterium isolated from tidal flat sediment

A novel Gram-negative and rod-shaped bacterium, designated N8^T, was isolated from tidal flat sediment. Phylogenetic analysis based on 16S rRNA gene sequences showed that N8^T strain is associated with the family Phyllobacteriaceae: two uncultured clones (98.4 and 99.8% 16S rRNA gene sequence similarity) and the genus Mesorhizobium (≤97.0%). The novel strain formed a separate clade with uncultured clones in the phylogenetic tree based on 16S rRNA gene sequences. Cellular fatty acid profiles predominately comprised C_18:1 ω7c and C_19:0 cyclo ω8c. The major isoprenoid quinone is ubiquinone-10 and genomic DNA G+C content is 53.4 mol%. The polyphasic taxonomic study indicates that the novel strain N8^T represents a novel species of the new genus in the family Phyllobacteriaceae, named Aliihoeflea aestuarii. The type strain is N8^T (= KCTC 22052^T= JCM 15118^T= DSM 19536^T).     

Streptosporangium shengliensis sp. nov., a novel actinomycete isolated from a lake sediment

A novel actinomycete, designated strain NEAU-GH7^T, was isolated from a lake sediment and characterized using a polyphasic approach. Strain NEAU-GH7^T was Gram-stain positive, aerobic, non-spore-forming and produced spherical sporangia. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain NEAU-GH7^T formed a monophyletic clade with the closest relative Streptosporangium longisporum DSM 43180^T (99.0 %), an association that was supported by a bootstrap value of 74 % in the neighbour-joining tree and also recovered with the maximum-likelihood algorithm. However, the low level of DNA–DNA relatedness allowed the strain to be differentiated from its closest relative. Moreover, strain NEAU-GH7^T could also be differentiated from S. longisporum DSM 43180^T and other Streptosporangium species showing high 16S rRNA gene sequence similarity (>98.0 %) by morphological and physiological characteristics. On the basis of phylogenetic analysis, DNA–DNA hybridization and phenotypic characteristics, strain NEAU-GH7^T should be classified as a new species of the genus Streptosporangium, for which the name Streptosporangium shengliensis sp. nov. is proposed. The type strain is NEAU-GH7^T (=CGMCC 4.7105^T=DSM 45881^T).