Unidentified Polar Lipids Research Articles

Maritimibacter harenae sp. nov. and Sneathiella litorea sp. nov.: members of Alphaproteobacteria isolated from sea sand.

Two Gram-negative, rod bacteria, strains DP07T and DP05T, showing catalase- and oxidase-positive activities, were isolated from sea sand in South Korea. Strain DP07T was strictly aerobic and had a yellow colony colour. Contrastingly, strain DP05T was facultatively aerobic and had a creamy colony colour. Both strains contained ubiquinone-10 as the sole isoprenoid quinone. Strain DP07T contained cyclo-C19:0 ω8c, C16:0, summed feature 8 (comprising C18:1 ω7c and/or C18:1 ω6c), and C16:0 2-OH as the major fatty acids and phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid, and an unidentified polar lipid as the major polar lipids. Strain DP05T contained C16:0, cyclo-C19:0, and summed feature 8 (comprising C18:1 ω7c and/or C18:1 ω6c) as the major fatty acids and phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminophospholipid, and two unidentified polar lipids as the major polar lipids. Cadaverine was detected as the predominant polyamine in both strains. The DNA G + C contents of strains DP07T and DP05T were 66.1mol% and 51.8mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains DP07T and DP05T formed close phylogenetic lineages with Maritimibacter alkaliphilus HTCC2654T (similarity, 98.1%) and Sneathiella chungangensis CAU 1294T (similarity, 98.5%), respectively. The average nucleotide identity and DNA-DNA hybridisation values between strain DP07T and M. alkaliphilus were 80.0% and 23.0%, respectively, and those between strain DP05T and S. chungangensis were 77.1% and 19.9%, respectively. Based on the results of phenotypic, chemotaxonomic, and molecular analyses, strains DP07T and DP05T represent two novel species of the genera Maritimibacter and Sneathiella, respectively, for which we propose the following names: Maritimibacter harenae sp. nov. and Sneathiella litorea sp. nov. The type strains of M. harenae and S. litorea were DP07T (= KACC 21429T = JCM 33811T) and DP05T (= KACC 21431T = JCM 33810T), respectively.

Marinobacter alexandrii sp. nov., a novel yellow-pigmented and algae growth-promoting bacterium isolated from marine phycosphere microbiota.

The marine phycosphere harbors unique cross-kingdom associations with ecological relevance. During investigating the diversity of phycosphere microbiota of marine harmful algal blooms dinoflagellates, a faint yellow-pigmented bacterium, designated as strain LZ-8, was isolated from paralytic shellfish poisoning toxin-producing dinoflagellate Alexandrium catenella LZT09. The new isolate appeared to have growth-promoting potential toward its algal host. Molecular analysis using 16S rRNA gene, housekeeping rpoD gene and whole-genome sequence comparison indicated that strain LZ-8T wasa novel gammaproteobacterium of the family Alteromonadaceae. The major fatty acids of strain LZ-8T were C16:0, C18:1 ω9c, C12:0 3-OH, summed feature 3, C16:1 ω9c, C12:0 and summed feature 9. The major isoprenoid quinone was Q-9. Polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipid, two unidentified aminolipids and six unidentified polar lipids. The genomic DNA G+C content was 57.36mol%. Based on genome sequencing, several biosynthetic gene clusters responsible for bacterial biosynthesis of carotenoids and siderophores that may involve in algae-bacterial interactions were identified in the genome of strain LZ-8T. The polyphasic characterization indicated that strain LZ-8T represents a novel Marinobacter species. The name Marinobacter alexandrii sp. nov., type strain LZ-8T (= CCTCC AB 2018386T = KCTC 72198T) is proposed.

Foetidibacter luteolus gen. nov., sp. nov., isolated from the rhizosphere of Salvia miltiorrhiza.

A polyphosphate-producing bacterium, YG09T, was isolated from the rhizosphere of Salvia miltiorrhiza. Its colonies were 2.0-3.0mm in diameter, smooth, circular, convex and yellow after growth on R2A at 28°C for 72h, with aerobic, Gram-stain-negative, non-motile and rod-shaped bacteria. The strain was found to grow at 10-40°C (optimum 37°C), pH 5.5-8.0 (optimum 6.0), with 0-0.6% (w/v) NaCl (optimum 0). Chemotaxonomic analysis showed menaquinone-7 as the only quinone present; C15: 1 iso G, C15: 1 iso, C16: 0, C16: 0 3OH, C17: 0 iso 3OH, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) as the major fatty acids (> 5%), and phosphatidylethanolamine, three unidentified phospholipids, four unidentified polar lipids, three unidentified aminolipids, and one unidentified amino phospholipid as the polar lipids. The DNA G + C content was 44.6mol%. The 16S rRNA gene sequences of the isolate showed highest similarities to Panacibacter ginsenosidivorans Gsoil 1550T (93.6%), Filimonas endophytica SR2-06T (93.4%), Parasegetibacter terrae SGM2-10T (92.8%), and Arvibacter flaviflagrans C-1-16T (92.7%), within the family Chitinophagaceae of the phylum Bacteroidetes. The ANI values between strain YG09T and Panacibacter ginsenosidivoran Gsoil 1550T, Filimonas endophytica SR2-06T and Filimonas lacunae YT21T were 69.4, 68.3 and 68.7%, respectively. Based on phenotypic, genotypic and phylogenetic analyses, strain YG09T represents a novel genus in the family Chitinophagaceae, for which the name Foetidibacter luteolus gen. sp. nov. is proposed. The type strain is Foetidibacter luteolus YG09T (= MCCC 1K04042T = KCTC 72595T).

Thermaurantiacus tibetensis gen. nov., sp. nov., a novel moderately thermophilic bacterium isolated from hot spring microbial mat in Tibet.

Two bacterial strains SYSU G02173T and SYSU G03142 were isolated from hot springs in Tibet, China. Based on the results of nearly full-length 16S rRNA gene sequences and phylogenetic analyses, strains SYSU G02173T and SYSU G03142 were assigned to the family Sphingosinicellaceae, and were closest to Sandaracinobacter sibiricus RB16-17T (96.04% and 96.12% similarity, respectively). Cells of the both new strains were observed to be motile rod-shape, Gram-staining negative. Growth occurred at pH 6-8 (optimal: pH 7.0) and 37-55°C (optimal: 45°C) with 0-1.0% (w/v) NaCl in T4 broth. The cells were found to be positive for oxidase and catalase activities. The major respiratory ubiquinone was Q-8. The major fatty acids were identified as summed feature 8 (C18:1 ω7c and/or C18:1 ω6c), C16:0, C14:0 2-OH. The major polar lipids were found to consist of sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified phospholipid, one unidentified glycolipid, three unidentified aminolipids and two unidentified polar lipids. The DNA G + C contents of strains SYSU G02173T and SYSU G03142 were 71.8%. The average nucleotide identity (ANI) value between strain SYSU G02173T and SYSU G03142 was 99.98%. The amino acid identity (AAI) values between them and their closely related species were below 66.14%. The isolates are characterized by aerobic growth, a yellow endocellular pigment and a higher optimum growth temperature. The results showed that strains SYSU G02173T and SYSU G03142 represent a novel species of a novel genus in the family Sphingomonadaceae, and thus the name Thermaurantiacus tibetensis (type strain SYSU G02173T = KCTC 72052T = CGMCC 1.16680T) is proposed.

Alcanivorax profundimaris sp. nov., a Novel Marine Hydrocarbonoclastic Bacterium Isolated from Seawater and Deep-Sea Sediment

Two novel Alcanivorax-related strains, designated ST75FaO-1T and 521-1, were isolated from the seawater of the South China Sea and the deep-sea sediment of the West Pacific Ocean, respectively. Both strains are Gram-stain-negative, rod-shaped, and non-motile, and grow at 10-40°C, pH5.0-10.0, in the presence of 1.0-15.0% (w/v) NaCl. Their 16S rRNA gene sequences showed 99.9% similarity. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that both strains belong to the genus Alcanivorax, and share 92.9-98.1% sequence similarity with all valid type strains of this genus, with the highest similarity being to type strain Alcanivorax venustensis DSM 13974T (98.0-98.1%). Digital DNA-DNA hybridization (dDDH) and average nucleotide identity values between strains ST75FaO-1T and 521-1 were 75.7% and 97.1%, respectively, while the corresponding values with A. venustensis DSM 13974T were only 25.4-25.6% and 82.4-82.7%, respectively. The two strains contained similar major cellular fatty acids including C16:0, C18:1 ω7c/ω6c, C19:0 cyclo ω8c, C16:1 ω7c/ω6c, C12:0 3-OH, and C12:0. The genomic G + C content of strains ST75FaO-1T and 521-1 were 66.3% and 66.1%, respectively. Phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, and one unidentified polar lipid were present in both strains. On the basis of phenotypic and genotypic characteristics, the two strains represent a novel species within the genus Alcanivorax, for which the name Alcanivorax profundimaris sp. nov. is proposed. The type strain is ST75FaO-1T (= MCCC 1A17714T = KCTC 82142T).

Oceanomicrobium pacificus gen. nov., sp. nov., a member of the family Rhodobacteraceae isolated from seawater of tropical western Pacific.

The Gram-stain-negative, aerobic, ovoid or rod-shaped bacterial strain, designated KN286T, was isolated from seawater of tropical western Pacific. Growth occurred between 15 and 40°C (optimally at 30-35°C), pH 6-9 (optimally at 7.0) and in the presence of 0.5-5.0% (w/v) NaCl (optimally between 2.0 and 3.0%). Strain KN286T contained Q-10 as the major respiratory quinone. The polar lipid profile contained phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, three phospholipids, three glycolipids, and three unidentified polar lipids. The predominant cellular fatty acid was summed feature 8 (composed of C18:1ω7c and/or C18:1ω6c). Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain KN286T was a member of the family Rhodobacteraceae and formed a distinct lineage. Strain KN286T has a genome size of 3.25 Mbp and a G + C content of 65.0mol%. It encoded with some genes for carbohydrate-active enzymes, such as GH20 (Glycoside Hydrolase Family 20) and PL1 (Polysaccharide Lyase Family 1) and did not encode with a set of genes for reduction of nitrate to nitrite (nitrate reductase gamma subunit, respiratory nitrate reductase alpha N-terminal and respiratory nitrate reductase beta C-terminal). Based on phylogenetic analyses with single-copy orthologous clusters, low isDDH value (19.6%), low ANI (72.4%) and low AAI (65.7%) results, differential chemotaxonomic and physiological properties, strain KN286T represents a novel species of a novel genus of the family Rhodobacteraceae, for which the name Oceanomicrobium pacificus gen. nov., sp. nov. is proposed. The type strain of Oceanomicrobium pacificus is KN286T (=CGMCC 1.17118T = KCTC 72430T).

Lunatibacter salilacus gen. nov., sp. nov., a member of the family Cyclobacteriaceae, isolated from a saline and alkaline lake sediment.

A non-motile, Gram-staining negative, catalase- and oxidase-positive, crescent-rod shaped bacterium, designated strain CUG 91308T, was isolated from a sediment sample of Qinghai Lake, Qinghai Province, China. Colonies on OSM agar were round, smooth, flat and pinkish-orange in colour. Strain CUG 91308T could grow at 15-37 °C, pH 6-12 and in the presence of up to 7.0 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CUG 91308T belonged to the family Cyclobacteriaceae and formed a clade with the genus Lunatimonas in the phylogenetic tree, but separated from any species of the known genera within the family. The genomic DNA G+C content is about 42.1 %. The predominant fatty acids (>10 %) were iso-C15 : 0 (21.1 %), summed feature 3 (C16 : 1 ω7c / C16 : 1 ω6c / iso-C15 : 0 2OH) (14.3 %), iso-C17 : 0 3OH (12.3 %) and summed feature 9 (iso-C17 : 1 ω9c / C16 : 0 10-methyl) (10.6 %). The polar lipids of strain CUG 91308T were phosphatidylethanolamine (PE) and four unidentified polar lipids. Strain CUG 91308T contained MK-7 as the major respiratory quinone. On the basis of phenotypic, genotypic and phylogenetic data, strain CUG 91308T represents a novel species of a novel genus in the family Cyclobacteriaceae, for which the name Lunatibacter salilacus gen. nov., sp. nov. is proposed. The type strain of the proposed new isolate is CUG 91308T (=KCTC 62636T=CGMCC 1.13593T).

Solimonas marina sp. nov., isolated from deep seawater of the Pacific Ocean.

A taxonomic study was carried out on strain C16B3T, which was isolated from deep seawater of the Pacific Ocean. The bacterium was Gram-stain-negative, oxidase- and catalase- positive and rod-shaped. Growth was observed at salinities of 0-8.0 % and at temperatures of 10-45 °C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain C16B3T belonged to the genus Solimonas, with the highest sequence similarity to Solimonas terrae KIS83-12T (97.2 %), followed by Solimonas variicoloris MN28T (97.0 %) and the other four species of the genus Solimonas (94.5 -96.8 %). The average nucleotide identity and estimated DNA-DNA hybridization values between strain C16B3T and the type strains of the genus Solimonas were 74.05-79.48 % and 19.5-22.5 %, respectively. The principal fatty acids (>5 %) were summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c; 20.9 %), iso-C16 : 0 (14.6 %), C16 : 1 ω5c (9.4 %), iso-C12 : 0 (8.4 %), summed feature 2 (C14 : 0 3-OH/iso I-C16 : 1 and C12 : 0 aldehyde; 6.8 %) and C16 : 0 (5.5 %). The G+C content of the chromosomal DNA was 65.37 mol%. The respiratory quinone was determined to be Q-8 (100 %). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unidentified aminolipids, six unidentified phospholipids and one unidentified polar lipid. The combined genotypic and phenotypic data show that strain C16B3T represents a novel species within the genus Solimonas, for which the name Solimonas marina sp. nov. is proposed, with the type strain C16B3T (=MCCC 1A04678T=KCTC 52314T).

Isolation, characterisation and genome analysis of a novel ginsenosides hydrolysing bacterium Ginsengibacter hankyongi gen. nov., sp. nov. isolated from soil.

A novel yellow-pigmented bacterial strain (designated BR5-29T), was isolated and its taxonomy was studied. Phylogenetic study based on the 16S rRNA and draft genome sequence placed the strain BR5-29T in a distinct lineage within the family Chitinophagaceae, sharing ≤ 93.4% sequence similarity with members of the closely related genera Ferruginibacter, Flavisolibacter, Flavitalea and Niastella. The novel isolate showed the highest sequence similarity to the genus Ferruginibacter. The draft genome of strain BR5-29T had a total length of 5,505,520 base pairs. A total of 4585 genes were identified, in which 4537 were CDS and 48 RNA genes were assigned a putative function. The genome annotation of BR5-29T showed 225 carbohydrate genes which may be responsible for the conversion of major ginsenosides to minor ginsenosides. Strain BR5-29T contained MK-7 as a predominant quinone, and iso-C15:0, iso-C15:0 G, iso-C17:0 3-OH, and C16:1 ω7c and/or C16:1 ω6c (summed feature 3) as major fatty acids. The polar lipids found in the strain BR5-29T were phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), five unidentified polar lipids (L1-L5), two unidentified aminolipid and one unidentified aminophospholipid. Our pilot data demonstrate that the novel isolate shares the similar major polar lipid PE, major quinone MK-7 and major fatty acids with the described members of the family Chitinophagaceae. However, the low 16S rRNA gene sequence (< 93.4%), the little high amount of C12:0, iso-C17:0 2-OH and iso-C15:1 2-OH fatty acids, low DNA G + C content, and the presence of DPG, PG and two unidentified polar lipids (L1 and L3 differentiate the BR5-29T from its closest phylogenetic neighbors. Thus, the isolate represents a novel genus and species in the family Chitinophagaceae for which the name Ginsengibacter hankyongi gen. nov., sp. nov. is proposed. The type strain is BR5-29T (= KACC 19446T = LMG 30462T). Thus, we predict that this novel strain may prove useful for the future research analysis (target gene cloning) and mass production of Rg3.

Noviherbaspirillum aerium sp. nov., isolated from air.

A Gram-stain-negative, strictly aerobic, non-spore-forming, rod-shaped, motile with polar flagella and pale-orange bacterium, designated strain 122213-3T, was isolated from air, collected at the foot of the Xiangshan Mountain, located in Beijing, PR China. Optimal growth occurred at 28 °C, at pH 7 and in the presence of 0-1 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that 122213-3T clustered with species of the genus Noviherbaspirillum and formed a distinct sublineage, showing highest similarities to Noviherbaspirillum malthae CC-AFH3T (96.88 %), Noviherbaspirillum massiliense JC206T (95.78 %) and Noviherbaspirillum aurantiacum SUEMI08T (95.78 %). The predominant cellular fatty acids were summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. The predominant quinone was ubiquinone 8 (Q-8). The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipid and two unidentified polar lipids. The polyamine pattern showed the presence of putrescine as the major polyamine, with minor amounts of 2-hydroxyputrescine. The DNA G+C content was 60.1 mol%. The phylogenetic analysis and physiological and biochemical data showed that strain 122213-3T should be classified as representing a novel species in the genus Noviherbaspirillum, for which the name Noviherbaspirillum aerium sp. nov. is proposed. The type strain of N. aerium is 122213-3T (=CFCC 14286T=LMG 30131T).

Muricauda brasiliensis sp. nov., isolated from a mat-forming cyanobacterial culture.

Strain K001 was isolated from a cyanobacterial culture derived from Abrolhos, a reef bank microbial mat (South Atlantic Ocean-Brazil). Cells of K001 are Gram stain-negative, catalase and oxidase-positive, non-motile, rod-shaped, and with or without appendages. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain K001 belongs to the genus Muricauda. The highest strain K001 16S rRNA gene identity, ANI, and dDDH, respectively, are with M. aquimarina (98.90%, 79.23, 21.60%), M. ruestringensis (98.20%, 80.82, 23.40%), and M. lutimaris (97.86%, 79.23, 22.70%). The strain grows at 15-37°C and between 0.5 and 10% NaCl. The major fatty acids of strain K001 are iso-C15:0, iso-C15:1 G, iso-C17:0 3-OH, and summed feature 3 (C16:1 ω6c and/or C16:1 ω7c). The polar lipids are represented by phosphatidylethanolamine, three unidentified aminolipids, and three unidentified polar lipids. The major respiratory quinone is MK-6. The G+C content of the DNA of strain K001 is 41.62mol%. Based on polyphasic analysis of strain K001, it was identified as a novel representative of the genus Muricauda and was named Muricauda brasiliensis sp. nov. The type strain is K001 (=CBMAI 2315T = CBAS 752T).

Adhaeribacter arboris sp. nov., and Adhaeribacter pallidiroseus sp. nov., novel bacteria isolated from birch tree (Betula platyphylla).

Two Gram-stain-negative, strictly aerobic, non-motile and rod-shaped bacterial strains, designated as HMF7605T and HMF7616T, were isolated from birch tree, in Yong-in, Republic of Korea. Strains HMF7605T and HMF7616T exhibited the highest 16S rRNA gene sequence similarities of 95.9 and 97.5 % to Adhaeribacter swui 17mud1-7T, 97.9 % between themselves. The values of average nucleotide identity and in silico DNA-DNA hybridization between strains HMF7605T and HMF7616T were 77.6 and 22.0 %, respectively. Phylogenetic analysis of the 16S rRNA gene sequences of the two strains revealed that they belonged to the genus Adhaeribacter within the family Hymenobacteraceae. The predominant fatty acids of both strains were iso-C15 : 0, summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c), C16 : 1 ω5c and summed feature 4 (comprising iso-C17 : 1 I and/or anteiso-C17 : 1 B). The both strains contained menaquinone-7 as the only isoprenoid quinone. The major polar lipid profiles of the two strains were similar with phosphatidylethanolamine, one unidentified aminophosphoglycolipid, one unidentified glycolipid and three unidentified polar lipids. The DNA G+C contents of strains HMF7605T and HMF7616T were 42.0 and 42.8 mol%, respectively. Based on the results of the phenotypic, genotypic, chemotaxonomic and phylogenetic investigation, two novel species, Adhaeribacter arboris sp. nov. and Adhaeribacter pallidiroseus sp. nov. are proposed. The type strains are HMF7605T (=KCTC 62465T=NBRC 113228T) and HMF7616T (=KCTC 62466T=NBRC 113229T), respectively.

Sphingobacterium chungjuense sp. nov., isolated from a freshwater lake.

A Gram-stain-negative, rod-shaped, aerobic, non-flagellated, chemoheterotrophic bacterium, designated strain IMCC25678T, was isolated from an artificial freshwater reservoir, Chungju Lake, in the Republic of Korea. The 16S rRNA gene sequence analysis indicated that strain IMCC25678T belongs to the genus Sphingobacterium with ≤98.7 % sequence similarities to Sphingobacterium species. Whole genome sequencing of strain IMCC25678T revealed a 3.9 Mbp genome size with a DNA G+C content of 42.2 mol%. The IMCC25678T genome shared ≤89.7 % average nucleotide identity and ≤21.4 % digital DNA-DNA hybridization values with closely related species of the genus Sphingobacterium, indicating that the strain represents a novel species. Summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), iso-C15 : 0 and iso-C17 : 0 3-OH were found to be the predominant cellular fatty acid constituents in the strain. The major respiratory quinone was MK-7. The major polar lipids were phosphatidylethanolamine, one unidentified phosphoglycolipid, one unidentified sphingolipid and three unidentified polar lipids. Based on the phylogenetic and phenotypic characteristics, strain IMCC25678T was considered to represent a novel species within the genus Sphingobacterium, for which the name Sphingobacterium chungjuense sp. nov. is proposed. The type strain is IMCC25678T (=KACC 19485T=NBRC 113130T).

Flavobacterium salmonis sp. nov. isolated from Atlantic salmon (Salmo salar) and formal proposal to reclassify Flavobacterium spartansii as a later heterotypic synonym of Flavobacterium tructae.

A Gram-staining-negative non endospore-forming strain, T13(2019)T was isolated from water samples from Atlantic salmon (Salmo salar) fry culture in Chile and studied in detail for its taxonomic position. The isolate shared highest 16S rRNA gene sequence similarities with the type strains of Flavobacterium chungangense (98.44 %) followed by Flavobacterium tructae and Flavobacterium spartansii (both 98.22 %). Menaquinone MK-6 was the predominant respiratory quinone in T13(2019)T. Major polar lipids were phosphatidylethanolamine, an ornithine lipid and the unidentified polar lipids L1, L3 and L4 lacking a functional group. The major polyamine was sym-homospermidine. The fatty acid profile contained major amounts of iso-C15 : 0, iso-C15 : 0 3-OH, iso-C17 : 0 3-OH, C15 : 0, summed feature 3 (C16 : 1 ω7c and/or iso-C15 : 0 2-OH) and various hydroxylated fatty acids in smaller amounts, among them iso-C16 : 0 3-OH, and C15 : 0 3-OH, which supported the grouping of the isolate into the genus Flavobacterium. Physiological/biochemical characterisation and ANI calculations with the type strains of the most closely related species allowed a clear phenotypic and genotypic differentiation. In addition it became obvious, that the type strains of F. tructae and F. spartansii showed 100 % 16S rRNA gene sequence similarities and ANI values of 97.21%/ 97.59 % and DDH values of 80.40 % [77.5 and 83%]. These data indicate that F. tructae and F. spartansii belong to the same species and it is proposed that F. spartansii is a later heterotypic synonym of F. tructae. For strain T13(2019)T (=CIP 111411T=LMG 30298T=CCM 8798T) a new species with the name Flavobacterium salmonis sp. nov. is proposed.

Flavobacterium panici sp. nov. isolated from the rhizosphere of the switchgrass Panicum virgatum.

A Gram-staining-negative non endospore-forming strain, PXU-55T, was isolated from the rhizosphere of the switchgrass Panicum virgatum and studied in detail to determine its taxonomic position. The results of 16S rRNA gene sequence analysis indicated that the isolate represented a member of the genus Flavobacterium. The isolate shared highest 16S rRNA gene sequence similarities with the type strains of Flavobacterium chungangense (98.78 %) and Flavobacterium chilense (98.64 %). The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (isDDH) values between the PXU-55T genome assembly and the ones of the most closely related type strains of species of the genus Flavobacterium were 87.3 and 31.9% (Flavobacterium defluvii), and 86.1 and 29.9% (Flavobacterium johnsoniae). Menaquinone MK-6 was the major respiratory quinone. As major polar lipids, phosphatidylethanolamine, an ornithine lipid and the unidentified polar lipids L2, L3 and L4 lacking a functional group were found. Moderate to minor amounts of another ornithine lipid, the unidentified lipid L1 and a glycolipid were present, as well. The major polyamine is sym-homospermidine. The fatty acid profiles contained major amounts of iso-C15:0, iso-C15:0 3-OH, iso-C17:0 3-OH, C15:0, summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH) and various hydroxylated fatty acids in smaller amounts, among them iso C16:0 3-OH, C16:0 3-OH and C15:0 3-OH, which supported the classification of the isolate as a member of the genus Flavobacterium. Physiological and biochemical characterisation and ANI calculations with the type strains of the most closely related species allowed a clear phenotypic and genotypic differentiation of the strain. For this reason, we propose that strain PXU-55T (=CIP 111646T=CCM 8914T) represents a novel species with the name Flavobacterium panici sp. nov.

Leeia aquatica sp. nov., isolated from freshwater.

A Gram-stain-negative, rod-shaped, obligately aerobic, motile by a single polar flagellum, chemoheterotrophic bacterium, designated strain IMCC25680T, was isolated from surface water in Chungju Lake, Republic of Korea. 16S rRNA gene sequence analysis revealed that strain IMCC25680T was most closely related to Leeia oryzae HW7T with 95.5% sequence similarity and formed a robust clade with L. oryzae HW7T. Whole genome sequencing showed that strain IMCC25680T had a genome 3.6 Mbp long with 60.7 mol% DNA G+C content. Average nucleotide identity and digital DNA-DNA hybridization values between strain IMCC25680T and L. oryzae HW7T were 72.4% and 18.5%, respectively, indicating that the novel strain represents a novel species of the genus Leeia. The major cellular fatty acids of strain IMCC25680T were iso-C16:0 and summed feature 3 (comprising C16:1 ω6c and/or C16:1 ω7c). The respiratory quinone detected in the strain was ubiquinone-8. The major polar lipids were found to be phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and two unidentified polar lipids. On the basis of the phylogenetic and phenotypic characterization, strain IMCC25680T was considered to represent a novel species within the genus Leeia, for which the name Leeia aquatica sp. nov. is proposed. The type strain is IMCC25680T (=KACC 19487T =NBRC 113132T).

Seramator thermalis gen. nov., sp. nov., a novel cellulose- and xylan-degrading member of the family Dysgonamonadaceae isolated from a hot spring.

Two anaerobic bacteria, designated strains SYSU GA16112T and SYSU GA16107, were isolated from a hot spring in Tengchong County, Yunnan Province, south-west PR China. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains SYSU GA16112T and SYSU GA16107 belong to the family Dysgonamonadaceae. Cells of strains SYSU GA16112T and SYSU GA16107 were Gram-stain-negative, rod-shaped and non-motile. The major fatty acids (>10 %) of strains SYSU GA16112T and SYSU GA16107 were identified as anteiso-C15 : 0 and anteiso-C17 : 0 3OH. The polar lipid profile of strain SYSU GA16112T was found to consist of phosphatidylethanolamine, two unidentified aminophospholipids, two unidentified phosphoglycolipids, two unidentified aminolipids and one unidentified polar lipid, while that of strain SYSU GA16107 consisted of phosphatidylethanolamine, two unidentified polar lipids, three unidentified aminophospholipids, two unidentified phosphoglycolipids and one unidentified aminolipid. The genomic DNA G+C contents of strains SYSU GA16112T and SYSU GA16107 were determined to be 41.90 and 41.89 %, respectively, and the average nucleotide identity value between them was 99.99 %. Based on their morphological and physiological properties, and results of phylogenetic analyses, strains SYSU GA16112T and SYSU GA16107 are considered to represent a novel species of a novel genus, for which the name Seramator thermalis gen. nov., sp. nov. (type strain SYSU GA16112T=CGMCC 1.5281T=KCTC 15753T) is proposed.

Limnobacter alexandrii sp. nov., a thiosulfate-oxidizing, heterotrophic and EPS-bearing Burkholderiaceae isolated from cultivable phycosphere microbiota of toxic Alexandrium catenella LZT09.

A novel Gram-negative, aerobic, motile and short rod-shaped bacterium with exopolysaccharides production, designated as LZ-4T, was isolated from cultivable phycosphere microbiota of harmful algal blooms-causing marine dinoflagellate Alexandrium catenella LZT09 which produces paralytic shellfish poisoning toxins. Strain LZ-4T was able to use thiosulfate (optimum concentration 10mM) as energy source for bacterial growth. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain LZ-4T belonged to the genus Limnobacter, showing high 16S rRNA gene sequences similarities with L. thiooxidans DSM 13612T (99.4%), L. humi NBRC 11650T (98.2%) and L. litoralis NBRC 105857T (97.2%), respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between LZ-4T and L. thiooxidans DSM 13612T were 78.9 and 21.9%, respectively. Both values were far lower than the thresholds (95-96% for ANI and 70% for dDDH) generally accepted for new species delineation. The respiratory quinone of strain LZ-4T was Q-8. The dominant cellular fatty acids were determined as summed feature 3 (C16:1 ω6c/ω7c), summed feature 8 (C18:1 ω6c/ω7c) and C16:0. Polar lipids profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids and three unidentified polar lipids. The genomic DNA G+C content of strain LZ-4T was 52.5mol%. Based on polyphasic characterization, strain LZ-4T represents a novel species of the genus Limnobacter, for which the name Limnobacter alexandrii sp. nov. is proposed. The type strain is LZ-4T (=CCTCC AB 2019004T =KCTC 72281T).

Brevibacillus migulae sp. nov., isolated from a Yellow River sediment sample.

Strain CFH S0501T, a novel Gram-stain-positive, aerobic, rod-shaped, endospore-forming and motile micro-organism with peritrichous flagella, was isolated from a sediment sample collected from the Yellow River in Henan Province, PR China. Optimum growth was observed at 28 °C, pH 7.0 and without NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the strain belonged to the genus Brevibacillus and was closely related to Brevibacillus centrosporus DSM 8445T and Brevibacillus ginsengisoli Gsoil 3088T (with 96.8 and 96.7 % sequence similarity, respectively). The predominant menaquinone was MK-7. Major cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. Polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, two unidentified phospholipids and an unidentified polar lipid. The cell-wall peptidoglycan was found to contain meso-diaminopimelic acid. The genome size was 5.26 Mbp with a G+C content of 49.7 mol%. The average nucleotide identity (ANI) and in silico DNA-DNAhybridization (DDH) values between CFH S0501T and the other species of the genus Brevibacillus were found to be low (ANIm <86.11 %, ANIb <70.30 % and DDH <25.00 %). Based on physiological properties, chemotaxonomic characteristics and low ANI and DDH results, strain CFH S0501T is considered to represent a novel species, for which the name Brevibacillus migulae sp. nov. is proposed. The type strain is CFH S0501T (=DSM 29940T=BCRC 80809T).

Wocania indica gen. nov., sp. nov., isolated from deep sea hydrothermal sulfide in the northwest Indian Ocean, and proposal to reclassify Flaviramulus ichthyoenteri as Wocania ichthyoenteri comb. nov.

A novel Gram-stain-negative, non-motile, strictly aerobic, rod-shaped bacterium was isolated from deep-sea hydrothermal sulfide in the northwest Indian Ocean Ridge and designated as strain IOP_32T. Strain IOP_32T could grow at 4-40 °C (optimum, 37 °C), pH 5-9 (optimum, pH 7-8) and salinity of 0-12 % NaCl (w/v; optimum, 2-3 %). The 16S rRNA gene sequence of strain IOP_32T is most similar to Bizionia fulviae EM7T, Bizionia berychis RA3-3-1T, Bizionia paragorgiae KMM 6029T and Oceanihabitans sediminis S9_10T with 95.5-95.3 % similarity. The phylogenomic analysis indicated that strain IOP_32T forms a distinct lineage with Flaviramulus ichthyoenteri Th78T within the family Flavobacteriaceae. The average nucleotide identity, average amino acid identity and percentage of conserved protein values between strain IOP_32T and the type strains of close genera were 72.3-78.5 %, 67.4-76.9 % and 56.3-61.6 %, respectively. The major cellular fatty acid was anteiso-C15 : 0. The respiratory quinone was MK-6. The polar lipids were mainly composed of phosphatidylethanolamine, an unidentified aminophospholipid and five unidentified polar lipids. Strain IOP_32T is significantly different from related genera, which is reflected by the wide adaptability to temperature and salinity levels, the composition of phospholipids and fatty acids, and the results of phylogenetic analyses. The phenotypic properties and phylogenetic data suggest that the lineage represents a novel genus and species within the family Flavobacteriaceae, for which the name Wocania indica gen. sp. nov. is proposed, with the type strain IOP_32T (=MCCC 1A14017 T=KCTC 62660 T). We also propose the reclassification of Flaviramulus ichthyoenteri as Wocania ichthyoenteri comb. nov. (Th78T=DSM 26285T=JCM 18634T=KCTC 32142T).