- Volume 69, Issue 4, 2019

A lipolytic, Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated BPTF-M16T, was isolated from tidal flat sediment on the Yellow Sea in the Republic of Korea. Strain BPTF-M16T grew optimally at 30 °C and in the presence of 2.0–3.0 % (w/v) NaCl. A phylogenetic tree of 16S rRNA gene sequences showed that strain BPTF-M16T fell within the clade comprising the type strains of Altererythrobacter species. Strain BPTF-M16T exhibited 16S rRNA gene sequence similarity values of 98.0 and 97.1 % to the type strains of Altererythrobacter ishigakiensis and A ltererythrobacter marinus , respectively, and of less than 97.0 % to the type strains of the other recognized species. Strain BPTF-M16T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c as the major fatty acid. The major polar lipids detected in strain BPTF-M16T were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid and one unidentified glycolipid. Mean DNA–DNA relatedness values of strain BPTF-M16T with the type strains of A. ishigakiensis and A. marinus were 22 and 13 %, respectively. The average nucleotide identity value between strain BPTF-M16T and the type strain of A. ishigakiensis was 76.80 %. Differential phenotypic properties, together with the phylogenetic and genetic data, revealed that strain BPTF-M16T is separated from recognized Altererythrobacter species. On the basis of the data presented here, strain BPTF-M16T is considered to represent a novel species of the genus Altererythrobacter , for which the name Altererythrobacter insulae sp. nov. is proposed. The type strain is BPTF-M16T (=KCTC 62421T=KACC 19609T=NBRC 113190T).

Cells of bacterial strains 4 G-K06T and 4MSK11T, isolated from soil samples collected from monsoon evergreen broad-leaved forest of the Dinghushan Mountain (112° 31′ E 23° 10′ N), Guangdong Province, PR China, were Gram-stain-negative, aerobic, non-spore-forming, non-motile and rod-shaped. Strain 4 G-K06T grew at 10–37 °C, pH 3.5–7.5 and 0–3.5 % (w/v) NaCl; while 4MSK11T grew at 4–42 °C, pH 3.5–7.5 and 0–2.5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed strain 4 G-K06T formed a clade with Dyella flagellata 4 M-K16T, Dyella acidisoli 4M-Z03T, Dyella humi DHG40T and Dyella nitratireducens DHG59T, while strain 4MSK11T formed a clade with Dyella caseinilytica DHOB09T and Dyella mobilis DHON07T, both within the genus Dyella . The result of the partial atpD, gyrB and lepA gene sequence analysis supported the conclusion based on 16S rRNA gene sequence analysis, which showed that these two strains represent two novel species of Dyella . The average nucleotide identity and digital DNA–DNA hybridization value for the whole genomes were 75.0–79.0 and 20.3–22.6 % between strains 4 G-K06T, 4MSK11T and those described Dyella species with genome sequences; while the DNA–DNA hybridization rates between strains 4 G-K06T, 4MSK11T and closely related Dyella species (without genome sequence) were 29.5–41.8 %. The major cellular fatty acids of these two strains were iso-C15 : 0, iso-C16 : 0 and iso-C17 : 1 ω9c, while the major polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and several unidentified phospholipids and aminophospholipids. The only ubiquinone of these two strains was ubiquinone-8. The DNA G+C contents of 4 G-K06T and 4MSK11T were 60.4 and 61.3 mol%, respectively. On the basis of the evidence presented here, strains 4 G-K06T and 4MSK11T represent two novel species of the genus Dyella , for which the names Dyella monticola sp. nov. (type strain 4 G-K06T=LMG 30268T=GDMCC 1.1188T) and Dyella psychrodurans sp. nov. (type strain 4MSK11T=KCTC 62280T=GDMCC 1.1185T) are proposed.

A Gram-staining-negative, strictly aerobic, non-motile strain, SYSUP0001T, was isolated from tubers of Gastrodia elata Blume. The 16S rRNA gene sequence result indicated that SYSUP0001T represents a member of the genus Sphingomonas , with the highest sequence similarity (97.7 %) to the type strain of Sphingomonas ginsengisoli . SYSUP0001T grew at 14–37 °C and pH 6–8, with optimum growth at 28 °C and pH 7. Tolerance to NaCl was up to 3 % (w/v) with optimum growth in the absence of NaCl. The respiratory quinone was Q-10. The major fatty acids were C18 : 1ω7c, Summed feature 3 (C16 : 1ω7c/C16 : 1ω6c), and C16 : 0. The polar lipids were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), sphingoglycolipid (SGL), phosphatidylcholine (PC) and four unidentified polar lipids (L). The DNA G+C content was 67.5 %. The average nucleotide identity (ANI) values between SYSUP0001T and closely related members of the genus Sphingomonas were below the cut-off level (95–96 %) for species delineation. On the basis of the phenotypic, phylogenetic and chemotaxonomic characterizations, SYSUP0001T represents a novel species of the genus Sphingomonas , for which the name Sphingomonasmesophila sp. nov. is proposed. The type strain is SYSUP0001T (=KCTC 62179 T=CGMCC 1.16462T).

A novel marine Gram-stain-negative, non-spore-forming, motile, aerobic, coccoid or ovoid bacterium, designated as strain DSL-16T, was isolated from a tidal flat sediment on the East China Sea and characterized phylogenetically and phenotypically. Optimal growth of the strain occurred at 35 °C (range 4–40 °C), at pH 6 (range 5–11) and with 4 % (w/v) NaCl (range 1–14 %). The nearest phylogenetic neighbour was Paracoccus seriniphilus DSM 14827T (98.2 % 16S rRNA gene sequence similarity). The digital DNA–DNA hybridization value between strain DSL-16T and P. seriniphilus DSM 14827T was 19.5±2.2 %. The average nucleotide identity value between strain DSL-16T and P. seriniphilus DSM 14827T was 83.6 %. The sole respiratory ubiquinone was Q-10. The major polar lipids were phosphatidylmonomethylethanolamine (PME), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylethanolamine (PE), diphosphatidyglycerol (DPG) and glycolipid (GL). The predominant cellular fatty acids of strain DSL-16T were C18 : 1ω7c, C18 : 0 and 11-methyl C18 : 1ω7c. The G+C content of the genomic DNA was 64.5 mol%. The combined genotypic and phenotypic data indicated that strain DSL-16T represents a novel species of the genus Paracoccus , for which the name Paracoccus sediminilitoris sp. nov. is proposed. The type strain is DSL-16T (=KCTC 62644T=MCCC 1K03534T).

A Gram-stain-negative, motile bacterium, designated strain YE3T, was isolated from activated sludge obtained from a municipal wastewater treatment plant in Daejeon Metropolitan City, Republic of Korea. The cells were oxidase- and catalase-positive, and grew under aerobic conditions at 10–40 °C (optimum, 30 °C), with 1.0–8.0 % (w/v) NaCl (1.0 %) and at pH 5.5–9.0 (pH 7.0). Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain YE3T was most closely related to Pusillimonas harenae KACC 14927T (98.2 % sequence similarity) and Pusillimonas ginsengisoli KCTC 22046T (98.0 %). DNA–DNA relatedness values for strain YE3T and P. harenae KACC 14927T, P. ginsengisoli KCTC 22046T and P. soli KCTC 22455T were 28.7±2.27 %, 21.3±1.16 %, and 14.0±0.67 %, respectively. The genomic G+C content of the type strain YE3T was 59.3 mol%, as determined by whole-genome sequencing. The dominant fatty acids were C16 : 0 (39.2 %) and C17 : 0cyclo (37.5 %). The major polar lipids of strain YE3T were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Two aminophospholipids and four unidentified lipids were also detected. Furthermore, strain YE3T was able to oxidize thiosulfate under heterotrophic conditions. Based on the phenotypic, genotypic, chemotaxonomic and phylogenetic analyses, strain YE3T represents a novel species of the genus Pusillimonas , for which the name Pusillimonas thiosulfatoxidans sp. nov. is proposed. The type strain is YE3T (=KCTC 62737T=NBRC 113113T).

A psychrotolerant non-spore-forming sulfate-reducing bacterium, strain K3ST, was isolated from a Yamal Peninsula cryopeg within permafrost. Strain K3ST grew at subzero temperatures and required Na+ for growth. The new bacterium was able to use lactate, formate, pyruvate, fumarate, alanine, ethanol and molecular hydrogen as electron donors in the presence of sulfate, and used sulfate, sulfite, thiosulfate and elemental sulfur as electron acceptors in the presence of lactate. Fe(III)-citrate and Fe(III)-EDTA were reduced without visible growth. Major polar lipids were рhosphatidylserine, рhosphatidylethanolamine, phospholipids, cardiolipin and aminolipid; major cellular fatty acids were C16 : 1ω7, C16 : 0 and C18 : 1ω7; and the predominant isoprenoid quinone was MK-6 (H2). The genomic DNA G+C content was found to be 42.33 mol%. Phylogenetic analysis showed that the closest relative of the new isolate was Desulfovibrio ferrireducens strain 61T with 97.1 % 16S rRNA gene similarity. In addition, the ANI value between strain K3ST and D. ferrireducens 61T was 82.1 %. On the basis of the genomic and polyphasic taxonomy data of strain K3ST, we conclude that the strain is a representative of a novel species Desulfovibrio gilichinskyi sp. nov. (=VKM B-2877T=DSM 100341T).

A taxonomic study was carried out on strain HN-E23T, which was isolated from sponge collected from Yangpu Bay, Hainan, China. Cells of strain HN-E23T were Gram-stain-negative, non-motile, orange-yellow-pigmented, short rods, that could grow at 10–40 °C (optimum, 28 °C), at pH 5–11 (optimun, pH 7) and in 0.5–12 % (w/v) NaCl (optimum, 3 %). This isolate was positive for oxidase, catalase, and the hydrolysis of aesculin, but negative for indole production and the reduction of nitrate. The phylogenetic tree based on 16S rRNA gene sequences revealed that strain HN-E23T formed a distinct phylogenetic lineage within the cluster comprising Erythrobacter strains. Strain HN-E23T shared the highest 16S rRNA gene sequence similarity to Erythrobacter aquimixticola JSSK-14T (97.2 %), followed by Erythrobacter atlanticus s21-N3T (96.6 %), Erythrobacter luteus KA37T (96.5 %) and Erythrobacter citreus RE35F/1T (96.4 %). The digital DNA–DNA hybridization (dDDH) and the average nucleotide identity (ANI) values between strain HN-E23T and JSSK-14T were 18.8 and 74.9 %, respectively. The dDDH and ANI values are below the standard cut-off criteria for delineation of bacterial species. The dominant fatty acids were summed feature 8 (C18 : 1ω7c/ω6c), C16 : 0 and summed feature 3 (C16 : 1ω7c/ω6c). The major polar lipids comprised phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, sphingoglycolipid, an unidentified glycolipid and six unidentified lipids. The respiratory lipoquinone was identified as Q-10. The G+C content of the genomic DNA was 65.5 mol%. Based on the phenotypic and phylogenetic data, strain HN-E23T represents a novel species of the genus Erythrobacter , for which the name Erythrobacter spongiae sp. nov. is proposed, with the type strain HN-E23T (=MCCC 1K03331T=LMG 30457T).

A Gram-stain-negative, aerobic, non-flagellated, non-motile bacterium, designated strain WRN-8T, was isolated from marine sediment of the Yellow Sea, China (36° 5′ 33′′ N, 121° 20′ 37′′ E). Colonies of strain WRN-8T were 0.2–0.3 µm wide, 2.1–2.8 µm long, catalase-positive and oxidase-positive. Colonies on marine agar solid media were circular, wet, smooth, light yellow and approximately 1.3 mm in diameter. Growth occurred optimally at 33–37 °C, pH 7.0–7.5 and in the presence of 2–4 % NaCl (w/v). Phylogenetic analysis of the 16S rRNA gene indicated that strain WRN-8T is a member of the genus Microbulbifer within the family Microbulbiferaceae , and the closest described neighbour in terms of 16S rRNA gene sequence identity is Microbulbifer aestuariivivens KCTC 52569T (98.1 %). The major respiratory quinone of strain WRN-8T is Q-8, its predominant fatty acids are iso-C15 : 0, iso-C17 : 0, C16 : 0, iso-C11 : 03-OH and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), and its major polar lipids are phosphatidylethanolamine, phosphatidylglycerol, glycolipid, an unidentified phospholipid and an unidentified lipid. The draft genome obtained in this study was 3 643 020 bp, and the G+C content was 59.2 mol%. DNA–DNA hybridization (<46.3 %) and average nucleotide identity (<86.7 %) values between strain WRN-8T and the closest-related recognized Microbulbifer species confirmed the novelty of this new species. Therefore, we propose a novel species in the genus Microbulbifer to accommodate the novel isolate: Microbulbifer flavimaris sp. nov. (type strain WRN-8T=KCTC 42989T=ACCC 19926T).

A Gram-stain-negative, rod-shaped and aerobic bacterium, designated HYN0004T, was isolated from lake water. The strain grew at 15–35 °C and pH 7.0–9.0 on R2A. The isoprenoid quinone was Q10 and major polar lipids were phosphatidylglycerol and one unidentified glycolipid. The genome was 2.83 Mb with a DNA G+C content of 69.9 mol%. 16S rRNA gene sequence analyses revealed that HYN0004T represented a member of the genus Phenylobacterium and shared sequence similarities with Phenylobacterium conjunctum (97.8 %), Phenylobacterium koreense (97.5 %), Phenylobacterium aquaticum (97.2 %), and Phenylobacterium heamatophilum (97.0 %). In addition to the low sequence similarities, the phylogenetic tree shapes indicated that HYN0004Trepresents an independent species of this genus. The genomic and phenotypic properties, including small genome size, inability to carry out numerous enzymatic reactions and high ratio of C18 : 1ω6c and/or C18 : 1ω7c in fatty acids, verified the differentiation between HYN0004T and related species. Thus, we propose a novel species of the genus Phenylobacterium , named as Phenylobacterium parvum sp. nov. The type strain is HYN0004T (=KACC 19185T=NBRC 112736T).

A Gram-staining negative, aerobic, oval-shaped bacterium, designated strain PTG4-2T, was isolated from deep-sea sediment of the Indian Ocean. Growth was observed with 1–9 % (w/v) NaCl with optimal growth with 3 %, at pH 6.0–10.0 with an optimum of pH 7.0, and at 4–40 °C with an optimum of 30 °C. Positive for catalase and oxidase. The results of a 16S rRNA gene sequence comparison indicated that PTG4-2T was most closely related to Acuticoccus yangtzensis JL1095T (97.3 %), followed by Acuticoccus kandeliae J103T (96.5 %), all other species shared <93 % sequence similarity. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that PTG4-2T forms a distinct lineage within the genus Acuticoccus , and revealed that the genus Acuticoccus forms a novel family-level clade in the order Rhizobiales . The ANI and the DNA–DNA hybridization estimate values between PTG4-2T and two type strains (A. yangtzensis JL1095T and A. kandeliae J103T) were 79.9–76.2 % and 23.1–20.8 %, respectively. PTG4-2T contained Q-10 as the predominant ubiquinone. The principal fatty acids (>5 %) were summed feature 8 [C18 : 1 ω7c/ω6c (72.2 %)], C18 : 0 (8.4 %), C20 : 1 ω7c (6.4 %) and C16 : 0 (6.3 %). The polar lipids consisted of phosphatidylglycerol, three unidentified phospholipids, two unidentified glycolipids, one unidentified aminolipid and one unknown lipid. The DNA G+C content of PTG4-2T is 69.2 mol%. On the basis of the polyphasic taxonomic evidence presented in this study, PTG4-2T should be classified as representing a novel species of the genus Acuticoccus , for which the name Acuticoccus sediminis sp. nov. is proposed, with the type strain PTG4-2T (=MCCC 1A01274T=KCTC 52323T). In addition, a novel family, Acuticoccaceae fam. nov., is proposed to accommodate the genus Acuticoccus .

We isolated five novel bacterial strains from symptomatic bark tissue of Populus × euramericana canker that were Gram-stain-negative, non-motile, aerobic oxidase-negative and catalase-positive. Growth occurred at 10–41 °C and at pH 5.0–7.0, with optimum growth at 30 °C and pH 7.0. Additionally, growth occurred in conditions of 0–5 % (w/v) salinity, but not above 7 % NaCl. The 16S rRNA gene sequences of the novel strains shared the highest similarity with Sinorhodobacter ferrireducens SgZ-3T (97.1 %). The average nucleotide identity values between the novel strains and two type strains (S.inorhodobacter ferrireducens CCTCC AB2012026T and ‘ S inorhodobacter hungdaonensis’ CGMCC 1.12963T) were 78.4–78.9 %, which were lower than the proposed species boundary cut-off (95–96 %). The main polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified lipid and phosphatidylcholine. The main respiratory quinone was Q-10, and major fatty acids were C18 : 1ω7c and/or C18 : 1 ω6c. Based on data from a polyphasic taxonomy study, the novel strains represent a novel species of the genus Sinorhodobacter , for which the name Sinorhodobacter populi sp. nov. is proposed. The type strain is sk2b1T (=CFCC 14580T=KCTC 52802T).

An aerobic, motile, Gram-stain-negative bacterium, designated strain NS1T, was isolated from interfacial sediment from Taihu Lake, China. The strain formed yellow colonies on R2A medium. Cells were ovoid to rod-shaped and non-spore-forming. Growth occurred at 15–40 °C (optimum, 28 °C), at pH 5.0–10.5 (optimum, 6.5–7.5) and in the presence of 0–1 % (w/v) NaCl (optimum, 0 %). Phylogenetic trees based on 16S rRNA gene sequences showed that strain NS1T represented a member of the genus Altererythrobacter and had the highest sequence similarity to Altererythrobacter troitsensis CCTCC AB 2015180T (97.1 %). The average nucleotide identity value between strain NS1T and the closest related strain based on their genomes was 78.6 %. The predominant ubiquinone was Q-10. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, an unidentified phospholipid, an unidentified glycolipid and six unidentified lipids. The genomic DNA G+C content was 66.6 mol%. On the basis of phenotypic and genotypic characteristics, strain NS1T represents a novel species of the genus Altererythrobacter , for which the name Altererythrobacter amylolyticus sp. nov. is proposed. The type strain is NS1T (=CGMCC 1.13679T=NBRC 113553T).

Four strains isolated from sediment sampled at the front of a retreating glacier on northern Ellesmere Island in the Canadian high Arctic, namely JCM 32575T, JCM 32576, JCM 32577 and JCM 32578, belong to a novel psychrophilic basidiomycetous yeast species in the genus Mrakia. Molecular phylogenetic analysis indicated that these strains are most closely related to the type strains of Mrakia aquatica and Mrakianic combsii, but with 8–9 and 7–12 nt substitutions in ITS and in the D1/D2 domain of the LSU rRNA gene, respectively. The strains grew at sub-zero temperatures and in vitamin-free media, with lipase and cellulase highly active even at −3 °C. These characteristics likely allow this yeast species to grow and survive in extremely cold, oligotrophic environments, such as the fronts of retreating glaciers in the high Arctic. The name Mrakia hoshinonis sp. nov. is proposed, with type strain JCM 32575T (UAMH 11969) and MycoBank number MB 825484.

In this study, we propose a new genus, Victoriomyces, with a new species, Victoriomyces antarcticus, isolated from soil samples collected in Victoria Land, Antarctica. To determine its taxonomic status and evolutionary relationships, phylogenetic analysis was performed on DNA sequences from the nuclear 18S rRNA, 28S rRNA and the second largest subunit of RNA polymerase II (RPB2) genes. Victoriomyces antarcticus constitutes one well-supported distinct lineage within the Cephalothecaceae (family incertae sedis in Sordariomycetes), in which the only recognised asexual morphs belong to the genus Phialemonium and to Acremonium thermophilum. Victoriomyces antarcticus can be clearly distinguished from these taxa by means of DNA sequence analysis and its morphological traits that consist in having a Metarhizium-like asexual morph, dark red-coloured disk-like structures, immature bodies and the production of an intense red pigment in the growth media. Finally, we inferred the divergence time of V. antarcticus and the Cephalothecaceae using Bayesian analysis and secondary calibration. The holotype of V. antarcticus is FBL 165. The ex-type strain has been deposited as MUT 3686T and CCF 6158T. An additional strain of the species is FBL 577. The MycoBank number is MB 823713 for the genus and MB 823714 for the species.