- Volume 71, Issue 7, 2021

Taxonomic positions of six isolates, which were recovered from two different environments in Jeju, Republic of Korea, were examined by a polyphasic analysis. Cells of the isolates were Gram-reaction-negative, facultatively anaerobic, motile and rod-shaped and showed growth at 4–30 °C, pH 4.0–9.0 and with 0–6 (w/v) NaCl. In phylogenomic analysis based on 92 single-copy core genes, it was shown that the isolates belonged to the genus Rahnella and formed three distinct sublines within the genus. The isolates shared 16S rRNA gene sequence similarities of 97.9–100 % with one another. The isolates contained ubiquinone-8 was as the major isoprenoid quinone. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and an unidentified aminophospholipid. The predominant fatty acids were C16 : 0 and C17 : 0 cyclo. The G+C content of their genomic DNA was 52.8–53.1 %. Average nucleotide identity and digital DNA–DNA hybridization values supported that strains SAP-17T and Lac-M11T represented two new species of the genus Rahnella , whereas strain SAP-10 was a strain of Rahnella victoriana . Based on the results obtained here, Rahnella laticis sp. nov. (type strain SAP-17T=KCTC 72960T=NBRC 114723T=CCM 9079T) and Rahnella contaminans sp. nov. (type strain Lac-M11T=KACC 21743T=NBRC 114406T) are proposed. Also, an emended description of the genus Rahnella is given on the basis of our physiological and chemotaxonomic results.

A Gram-stain-negative, aerobic and non-motile bacterium, strain sand1-3T, was isolated from beach sand collected from Haeundae Beach located in Busan, Republic of Korea. Based on the results of 16S rRNA gene sequence and phylogenetic analyses, Sphingomonas daechungensis CH15-11T (97.0 %), Sphingomonas edaphi DAC4T (96.8 %), Sphingomonas xanthus AE3T (96.5 %) and Sphingomonas oryziterrae YC6722T (96.0 %) were selected for comparing phenotypic and chemotaxonomic characteristics. Cells of strain sand1-3T grew at 7–50 °C (optimum, 30–35 °C), pH 5.0–8.0 (optimum, pH 7.0–8.0) and in the presence of 0–0.5 % (w/v) NaCl (optimum, 0 %). Major polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid, one unidentified glycolipid and one unidentified phosphoglycolipid. The major fatty acids were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c) and C18 : 1 2-OH. Moreover, the sole respiratory quinone and major polyamine were identified as ubiquinone-10 and homospermidine, respectively. The genomic DNA G+C content was 65.9 mol%. The digital DNA–DNA hybridization, average nucleotide identity and average amino acid identity values of strain sand1-3T and its reference strains with publicly available genomes were 17.9–18.9 %, 72.0–75.3 % and 63.3–76.5 % respectively. Based on polyphasic evidence, we propose Sphingomonas sabuli sp. nov. as a novel species within the genus Sphingomonas . The type strain is sand1-3T (=KCTC 82358T=NBRC 114538T).

A novel Gram-stain-negative and rod-shaped bacterial strain, designated as 4Y14T, was isolated from aquaculture water and characterized by using a polyphasic taxonomic approach. Strain 4Y14T was found to grow at 10–40 °C (optimum, 28 °C), at pH 7.0–9.0 (optimum, 7.0–8.0) and with 0–2 % NaCl (optimum, 1 %, w/v). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 4Y14T belonged to the genus Chitinilyticum with high levels of similarity to Chitinilyticum litopenaei c1T (97.8 %) and Chitinilyticum aquatile c14T (97.2 %). Phylogenomic analysis indicated that strain 4Y14T formed an independent branch distinct from the two type strains above. Digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain 4Y14T and the two type strains were, respectively, 25.3 and 25.0 %, and 81.2 and 80.3 %, which were well below the thresholds of 70 % DDH and 95–96 % ANI for species definition, implying that strain 4Y14T should represent a novel genospecies. The predominant cellular fatty acids of strain 4Y14T were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and iso-C16 : 0; the major polar lipids were diphosphatidylglycerol, phosphatidylcholine and phosphatidylethanolamine; and the sole respiratory quinone was Q-8. The genomic DNA G+C content was 60.1 mol%. Based on the phenotypic and genotypic analyses, strain 4Y14T is concluded to represent a novel species of the genus Chitinilyticum , for which the name Chitinilyticum piscinae sp. nov. is proposed. The type strain of the species is 4Y14T (=GDMCC 1.1934T=KACC 22080T).

A polyphasic taxonomic approach was used to characterize a Gram-stain-negative bacterium, designated strain CC-YST696T, harbouring antibiotic- and toxic compound-resistace genes, isolated from poultry manure in Taiwan. Cells of CC-YST696T were short rods, motile with polar flagella, catalase- and oxidase-positive. Optimal growth occurred at 30 °С, pH 9 and with 1 % NaCl. The results of phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by CC-YST696T associated with Devosia chinhatensis (97.9 % sequence identity), Devosia riboflavina (97.3 %) and Devosia indica (97.2 %), and with lower sequence similarity values to other species. Average nucleotide identity (ANI) values were 72.8–80.0 % (n=17) compared within the type strains of species of of the genus Devosia . CC-YST696T contained C16:0, C18:0, C18:1ω7c 11-methyl and C18:1ω6c/ C18:1ω7c as the predominant fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids, three unidentified glycolipids, two unidentified phospholipids and three unidentified lipids. The DNA G+C content was 62.2 mol% and the predominant quinone was ubiquinone Q-10. On the basis of its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence and ANI analyses, strain CC-YST696T is proposed to represent a novel species of the genus Devosia , for which the name Devosia faecipullorum sp. nov. (type strain CC-YST696T=BCRC 81284T=JCM 34167T) is proposed.

A Gram-stain-negative, aerobic, non-motile, rod-shaped bacterial strain (CAU 1508T) was isolated from marine sediment collected in the Republic of Korea. Growth was observed at 10–45 °C (optimum, 30 °C), pH 4.0–11.0 (optimum, pH 6.0–8.0) and with 0–8.0 % (w/v) NaCl (optimum, 2–4 %). The isolate formed a monophyletic clade in the phylogenetic analyses using 16S rRNA gene and whole-genome sequences, exhibiting the highest similarity to Chachezhania antarctica SM1703T (96.5 %), and representing a distinct branch within the genus Chachezhania (family Rhodobacteraceae ). Its whole genome sequence was 5.59 Mb long, with a G+C content of 65.7 mol% and 2183 predicted genes belonging to six functional categories. The average nucleotide identity and digital DNA–DNA hybridization values between CAU 1508T and C. antarctica SM1703T were 79.1 and 22.2 %, respectively. The predominant cellular fatty acids were C19 : 0 cyclo ω8c and summed feature 8 (C18 : 1  ω7c/C18 : 1  ω6c). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, two unidentified phospholipids and one unidentified aminophospholipid. The sole isoprenoid quinone was ubiquinone 10. Phenotypic phylogenetic properties supported the classification of CAU 1508T as representing a novel species of the genus Chachezhania , with the proposed name Chachezhania sediminis sp. nov. The type strain is CAU 1508T (=KCTC 62999T=NBRC 113697T).

An aerobic, Gram-stain-negative, bacterium, designated CLL3-39T was isolated from seashore sediment collected at a Tamarix chinensis forest in the Marine Ecology Special Reserve of Changyi, Shandong Province, PR China. Cells of strain CLL3-39T were olive-shaped and no flagellum was observed. Strain CLL3-39T grew optimally at 33 °C, pH 7.5 and salinity (sea salts) of 40 g l−1. The main fatty acids in the cell membrane of strain CLL3-39T comprised anteiso-C15 : 0 (22.3 %), iso-C15 : 0 (14.0 %), C16 : 0 (9.2 %) and summed feature 8 (contains C18 : 1  ω7c/C18 : 1  ω6c. 26. 7 %). The main polar lipids of CLL3-39T were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylcholine. The respiratory quinone was Q10. The G+C content of the genomic DNA of strain CLL3-39T was 69.6 mol%. The average nucleotide identity between CLL3-39T and Pseudoroseicyclus aestuarii DB-4T was 74.7 % and the in silico DNA–DNA hybridization value was 20.1 %. Phylogenetically, strain CLL3-39T belonged to the genus Pseudoroseicyclus , branching with only one type strain P. aestuarii DB-4T with 96.3 % 16S rRNA gene similarity, followed by Limimaricola cinnabarinus LL-001T (95.2 %). Based on its phenotypic, phylogenetic and chemotaxonomic characteristics, we propose strain CLL3-39T (=MCCC 1A14815T =KCTC 72665T) as a representative of a novel species in the genus Pseudoroseicyclus , for which the name Pseudoroseicyclus tamaricis sp. nov. is proposed.

A novel Gram-stain-negative, aerobic, rod-shaped bacterium with a single polar flagellum, designated strain 2T18T, was isolated from the gut of the freshwater mussel Anodonta arcaeformis collected in the Republic of Korea. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belonged to the genus Chitinibacter . Strain 2T18T formed a monophyletic clade with Chitinibacter fontanus KCTC 42982T, C. tainanensis KACC 11706T and C. alvei KCTC 23839T, with sequence similarities of 98.5, 98.4 and 95.9 %, respectively. Strain 2T18T exhibited optimal growth at 30 °C, at pH 8 and with 0.5 % (w/v) NaCl. The major isoprenoid quinone was ubiquinone-8 (Q-8). The predominant fatty acids were summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and C16 : 0. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified lipid, three unidentified phospholipids and two unidentified aminophospholipids. The G+C content of the genomic DNA was 50.6 mol%. The average nucleotide identity and digital DNA–DNA hybridization values between strains 2T18T and C. fontanus KCTC 42982T were below the thresholds used for the delineation of a novel species. Based on the phylogenetic, phenotypic, chemotaxonomic and genotypic characteristics, strain 2T18T represents a novel species of the genus Chitinibacter , for which the name Chitinibacter bivalviorum sp. nov. is proposed. The type strain is 2T18T (=KCTC 72821T=CCUG 74764T).

In this study, we reported a Gram-stain-negative, orange-coloured, rod-shaped, motile and faculatively anaerobic bacterium named strain PB63T, which was isolated from the deep-sea sediment from the Mariana Trench. Growth of PB63T occurred at 10–35 °C (optimum, 28 °C), pH 5.0–8.0 (optimum, 5.0–6.0) and with 0–7 % (w/v) NaCl (optimum, 2–3 %). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that PB63T represented a member of the genus Novosphingopyxis and was closely related to Novosphingopyxis baekryungensis DSM 16222T (97.9 % sequence similarity). PB63T showed tolerance to a variety of heavy metals, including Co2+, Zn2+, Mn2+ and Cu2+. The complete genome of PB63T was obtained, and many genes involved in heavy metal resistance were found. The genomic DNA G+C content of PB63T was 62.8 mol%. The predominant respiratory quinone of PB63T was ubiquinone-10 (Q-10). The polar lipids of PB63T contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, glycolipid, phosphatidylcholines and three unidentified lipids. The major fatty acids of PB63T included summed feature 8 (C18 : 1ω7c or/and C18 : 1ω6c), C14 : 0 2-OH, 11-methyl C18 : 1ω7c, C16 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C17 : 1ω6c. The results of phylogenetic, physiological, biochemical and morphological analyses indicated that strain PB63T represents a novel species of the genus Novosphingopyxis , and the name Novosphingopyxis iocasae sp. nov. is proposed with the type species PB63T (=CCTCC AB 2019195T=JCM 34178T).

Two phytopathogenic bacteria, MAFF 301380T and MAFF 301381, isolated from rot lesions of lettuce (Lactuca sativa L. var. capitata L.) in Japan, were characterized using a polyphasic approach. The cells were Gram-reaction-negative, aerobic, non-spore-forming, rod-shaped and motile with one to three polar flagella. Analysis of the 16S rRNA gene sequences showed that the strains belong to the genus Pseudomonas and are closely related to Pseudomonas cedrina subsp. cedrina CFML 96-198T (99.72 %), Pseudomonas cedrina subsp. fulgida P515/12T (99.65 %), Pseudomonas gessardii DSM 17152T (99.51 %), Pseudomonas synxantha DSM 18928T (99.44 %), Pseudomonas libanensis CIP 105460T (99.44 %) and Pseudomonas lactis DSM 29167T (99.44 %). The genomic DNA G+C content was 60.4 mol% and the major fatty acids consisted of summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c), C16 : 0 and summed feature 8 (C18 : 1  ω7c/C18 : 1  ω6c). Phylogenetic analysis using the rpoD gene sequences and phylogenomic analyses based on the whole genome sequences demonstrated that the strains are members of the Pseudomonas fluorescens subgroup but formed a monophyletic and robust clade separated from their closest relatives. The average nucleotide identity and digital DNA–DNA hybridization values between the strains and their closely related species were 88.65 % or less and 36.3 % or less, respectively. The strains could be distinguished from their closest relatives by phenotypic characteristics, pathogenicity towards lettuce and whole-cell MALDI-TOF MS profiles. The evidence presented in this study supports the classification of the strains as representing a novel Pseudomonas species, for which we propose the name Pseudomonas lactucae sp. nov., with the type strain MAFF 301380T (=ICMP 23838T).

A Gram-stain-negative, aerobic, pale yellow-coloured, rod-shaped marine bacterium designated strain YJ-S2-02T was isolated from salt flat sediment sampled in Yongyu-do, Republic of Korea. Strain YJ-S2-02T grew at pH 6.0–9.0 (optimum, pH 7.0), 10–40 °C (optimum, 30 °C) and with optimum 1 % (w/v) NaCl. The 16S rRNA gene sequence analysis indicated that strain YJ-S2-02T was closely related to Novosphingobium naphthalenivorans NBRC 102051T (97.8 %) followed by Novosphingobium mathurense SM117T (97.5 %), Novosphingobium indicum H25T (97.3 %), Novosphingobium pentaromativorans US6-1T (96.8 %), Novosphingobium fontis STM-14T (96.6 %), Novosphingobium endophyticum EGI60015T (96.5 %), Novosphingobium naphthae D39T (96.5 %) and Novosphingobium malaysiense MUSC 273T (95.9 %). The average nucleotide identity and estimated DNA–DNA hybridization values between YJ-S2-02T and related type strains were 77.0–77.9 % and 19.1–24.0 %. Strain YJ-S2-02T was characterized as having Q-10 as the predominant respiratory quinone and the principal fatty acids (>10 %) were summed feature 8 (C18 : 1  ω6c/ω7c, 20.7 %), C18 : 3  ω6c (16.3 %) and C17 : 1  ω6c (11.8 %). The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, sphingolipids and two unidentified lipids. The DNA G+C content of strain YJ-S2-02T was 65.6 mol%. On the basis of the polyphasic taxonomic evidence presented in this study, YJ-S2-02T should be classified as representing a novel species within the genus Novosphingobium , for which name Novosphingobium aureum is proposed, with the type strain YJ-S2-02T (=KACC 21677T =KCTC 72891T=JCM 33996T).

A new family, genus and species of centrohelid heliozoans, Clypifer cribrifer gen. nov., sp. nov. (Clypiferidae fam. nov.), from the Gulf of Aqaba (Israel) was studied with light and electron microscopy and SSU rRNA gene sequencing. Clypifer cribrifer has only one type of scales, partially running up the sides of the axopodia. Plate scales [0.8–2.3 (av. 1.5)×0.6–1.8 (av. 1.2) μm] are flat, elliptical or circular, fenestrated with holes of irregular shape and have a marginal rim and a very short axial rib. The cell diameter is 3.9–9.6 (av. 6.0) μm. Molecular phylogenetic analysis robustly places C. cribrifer in the C4 clade for which the new family Clypiferidae is proposed here. This position is confirmed with the short sequences in the panacanthocystid increased regions. The morphology of the new genus has similarities to the genus Raphidocystis. The probability that another Clypifer species was described under a different name in the centrohelid literature is discussed. Clypiferidae represent the second lineage of Pterocystida, which are characterized by the presence of only tangentially oriented plate scales of one type. Possible ways of evolution of the centrohelid siliceous coverings are also discussed.

Sporobolomyces lactosus is a pink yeast-like fungus that is not congeneric with other members of Sporobolomyces (Basidiomycota, Microbotryomycetes, Sporidiobolales). During our ongoing studies of pink yeasts we determined that S. lactosus was most closely related to Pseudeurotium zonatum (Ascomycota, Leotiomycetes, Thelebolales). A molecular phylogenetic analysis using sequences of the ITS region and the small and large subunit (SSU, LSU) rRNA genes, indicated that four isolates of S. lactosus, including three ex-type isolates, were placed in Thelebolales with maximum support. A new genus is proposed to accommodate S. lactosus, Inopinatum. This is the first pink yeast reported in Leotiomycetes.