Family Cyclobacteriaceae Research Articles

Arcicella gelida sp. nov. and Arcicella lustrica sp. nov., isolated from streams in China and re-examining the taxonomic status of all the genera within the families Spirosomataceae and Cytophagaceae.

Three Gram-stain-negative, aerobic, rod-shaped, non-motile strains (DC2WT, DC25WT, and LKC2W) were isolated from streams in China. Comparisons based on the 16S rRNA gene sequences showed that these three strains share 16S rRNA gene sequence similarity values over 97.0 % with the species of genus Arcicella. There was confusion due to the fact that all species of genera Flectobacillus, Aquirufa, and Sandaracinomonas show 16S rRNA gene sequence similarity of over 90.0 % to the above three strains, but the genus Flectobacillus belongs to the family Spirosomataceae and the genera Aquirufa and Sandaracinomonas belong to the family Cytophagaceae. Observing the phylogenetic trees, strains DC2WT, DC25WT, and LKC2W cluster closely with the species of genus Arcicella, but some species within the families Spirosomataceae and Cytophagaceae are not monophyletic. The phylogenomic tree also showed a confused phylogenetic relationships among these non-monophyletic species. Combining the phylogenetic relationships and average nucleotide identity values, the current taxonomic status of all the genera within the families Spirosomataceae and Cytophagaceae were re-examined. The genera 'Chryseosolibacter', 'Dawidia', and Chryseotalea should belong to the new family Chryseotaleaceae fam. nov., the genera Arcicella, Flectobacillus, Pseudarcicella, Aquirufa, and Sandaracinomonas should belong to the new family Flectobacillaceae fam. nov., the genera Fluviimonas, Taeseokella, Arcticibacterium, Emticicia, Jiulongibacter, Marinilongibacter, Lacihabitans, and Leadbetterella should belong to the new family Leadbetterellaceae fam. nov., the genus Litoribacter should be reassigned to the family Cyclobacteriaceae, and the genera Arundinibacter and Tellurirhabdus should be reassigned to the family Spirosomataceae. Strains DC2WT and DC25WT are reported to represent two novel species of the genus Arcicella, for which the names Arcicella gelida sp. nov. (type strain DC2WT=GDMCC 1.3209T=KCTC 92559T) and Arcicella lustrica sp. nov. (type strain DC25WT=GDMCC 1.3210T=KCTC 92557T) are proposed.

Description of a new freshwater bacterium Aquirufa regiilacus sp. nov., classification of the genera Aquirufa, Arundinibacter, Sandaracinomonas, and Tellurirhabdus to the family Spirosomataceae, classification of the genus Chryseotalea to the family Fulvivirgaceae and Litoribacter to the family Cyclobacteriaceae, as well as classification of Litoribacter alkaliphilus as a later heterotypic synonym of Litoribacter ruber

Strains LEOWEIH-7CT and LEPPI-3A were isolated from the Leopoldskroner Weiher, a lake located in the city of Salzburg, Austria. 16S rRNA gene similarities and phylogenetic reconstructions with 16S rRNA gene sequences as well as based on genome sequences revealed that the new strains belong to the A. antheringensis branch of the genus Aquirufa. Calculated whole-genome average nucleotide identity (gANI) and digital DNA–DNA hybridization (dDDH) values with the closely related type strains showed that the two strains represent a single new species. The strains grew aerobically and chemoorganotrophically, and the cells were rod shaped, on average 0.8 µm long and 0.3 µm wide, red pigmented and motile by gliding. The genome size of both strains was 2.6 Mbp and the G+C value was 41.9%. The genomes comprised genes predicted for the complete light-harvesting rhodopsin system and various carotenoids. We proposed to establish the name Aquirufa regiilacus sp. nov. for strain LEOWEIH-7CT (=DSM 116390T = JCM 36347T) as the type strain. Strain LEPPI-3A (=DSM 116391 = JCM 36348) also belongs to this new species. The calculated genome-based phylogenetic tree revealed that Aquirufa and some other genera currently allocated in the family Cytophagaceae need a reclassification. Aquirufa, Arundinibacter, Sandaracinomonas, and Tellurirhabdus should be designated to the family Spirosomataceae, the genus Chryseotalea to the family Fulvivirgaceae, and the genus Litoribacter to the family Cyclobacteriaceae. Furthermore, based on calculated gANI and dDDH values, Litoribacter alkaliphilus should be reclassified as a later heterotypic synonym of Litoribacter ruber.

Mariniradius sediminis sp. nov., a multi-xenobiotics degrading genes harbouring bacterium isolated from sediment of river.

A Gram-stain-negative, strictly aerobic, non-motile, catalase- and oxidase-positive, pink and rod-shaped strain, designated RY-2T, was isolated from sediment of Fuyang River located in Wuqiang County, Hengshui City, Hebei Province, PR China. The strain grew at 25-45 °C (optimum, 37 °C), pH 7.0-8.0 (optimum, pH 7.0) and in the presence of 0-1.5 % (w/v) NaCl (optimum, 1 %). From the phylogenetic analysis of the 16S rRNA gene sequence, strain RY-2T was affiliated to the genus Mariniradius, and had the highest 16S rRNA gene sequence similarity to Mariniradius saccharolyticus JCM 17389T (98.3 %) and the similarity values between strain RY-2T and other type strains was all below 89.3 %. The genome size of strain RY-2T was 4.75 Mb and the DNA G+C content was 46.6 %. Values of digital DNA-DNA hybridization and average nucleotide identity between strain RY-2T and the reference strain were 63.2 and 95.5 %, respectively. The major fatty acids (≥5.0 %) were iso-C15 : 0 (37.9 %), summed feature 9 (8.4 %, iso-C17 : 1 ω9c and/or C16 : 010-methyl), anteiso-C15 : 0 (8.2 %), iso-C17 : 0 3-OH (7.6 %) and summed feature 4 (5.2 %, iso-C17 : 1 I and/or anteiso-C17 : 1 B) and its sole menaquinone was MK-7. The polar lipids consisted of phosphatidylethanolamine, an unknown phosphoglycolipid, an unidentified phospholipid, two unidentified aminolipids, three unidentified glycolipids and nine unidentified lipids. Based on the results of biochemical, physiological, phylogenomic and chemotaxonomic analyses, strain RY-2T is considered to represent a novel species of the genus Mariniradius within the family Cyclobacteriaceae, for which the name Mariniradius sediminis sp. nov. is proposed. The type strain is RY-2T (=GDMCC 1.2781T=JCM 35631T).

Habitat distribution of the genus Belliella in continental waters and the description of Belliella alkalica sp. nov., Belliella calami sp. nov. and Belliella filtrata sp. nov.

The genus Belliella belongs to the family Cyclobacteriaceae (order Cytophagales, phylum Bacteroidota) and harbours aerobic chemoheterotrophic bacteria. Members of this genus were isolated from various aquatic habitats, and our analysis based on global amplicon sequencing data revealed that their relative abundance can reach up to 5-10 % of the bacterioplankton in soda lakes and pans. Although a remarkable fraction of the most frequent genotypes that we identified from continental aquatic habitats is still uncultured, five new alkaliphilic Belliella strains were characterized in detail in this study, which were isolated from three different soda lakes and pans of the Carpathian Basin (Hungary). Cells of all strains were Gram-stain-negative, obligate aerobic, rod-shaped, non-motile and non-spore-forming. The isolates were oxidase- and catalase-positive, red-coloured, but did not contain flexirubin-type pigments; they formed bright red colonies that were circular, smooth and convex. Their major isoprenoid quinone was MK-7 and the predominant fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 containing C16 : 1 ω6c and/or C16 : 1 ω7c. The polar lipid profiles contained phosphatidylethanolamine, an unidentified aminophospholipid, an unidentified glycolipid, and several unidentified lipids and aminolipids. Based on whole-genome sequences, the DNA G+C content was 37.0, 37.1 and 37.8 mol % for strains R4-6T, DMA-N-10aT and U6F3T, respectively. The distinction of three new species was confirmed by in silico genomic comparison. Orthologous average nucleotide identity (<85.4 %) and digital DNA-DNA hybridization values (<38.9 %) supported phenotypic, chemotaxonomic and 16S rRNA gene sequence data and, therefore, the following three novel species are proposed: Belliella alkalica sp. nov. (represented by strains R4-6T=DSM 111903T=JCM 34281T=UCCCB122T and S4-10), Belliella calami sp. nov. (DMA-N-10aT=DSM 107340T=JCM 34280T=UCCCB121T) and Belliella filtrata sp. nov. (U6F3T=DSM 111904T=JCM 34282T=UCCCB123T and U6F1). Emended descriptions of species Belliella aquatica, Belliella baltica, Belliella buryatensis, Belliella kenyensis and Belliella pelovolcani are also presented.

Penaeicolahalotolerans gen. nov., sp. nov., a novel bacterium of the family Cyclobacteriaceae isolated from a shrimp pond.

A Gram-stain-negative, non-motile, rod-shaped, aerobic bacterium (designated as LMIT005T) was isolated from shrimp ponds in Shantou, China. The new isolate was characterized taxonomically using a polyphasic approach. Based on 16S rRNA gene sequence analysis, strain LMIT005T was found to be affiliated with the family Cyclobacteriaceae of the order Cytophagales while appearing as a distinct lineage. The 16S rRNA gene sequence similarity between strain LMIT005T and Algoriphagus yeomjeoni KCTC 12309T, the closest type strain in the family, was 91.3 %. Strain LMIT005T grew optimally at 25 °C, pH 7 and in the presence of 2.0 % (w/v) NaCl. The DNA G+C content (data from genome sequence) was 40.5 mol%. Compared with reference strain A. yeomjeoni KCTC 12309T, the average nucleotide identity (ANI) of LMIT005T was 70 %. The sole respiratory quinone of LMIT005T was menaquinone (MK-7), and the major fatty acids were summed feature 3 (C16 : 1 ω6c / C16 : 1 ω7c). The polar lipids of strain LMIT005T were mainly composed of phosphatidylethanolamine, phosphatidylcholine, two unidentified amino lipids, two unidentified lipids, one unidentified glycolipid and one unidentified phospholipid. The draft genome of strain LMIT005T comprised 3 089 781 bp (3.09 Mb) nucleotides and 2773 genes. Antimicrobial resistant-related genes (blal, mexA, and mexb) were annotated in the genome of strain LMIT005T, which indicated that it might be able to resist β-lactam antibiotics. This was further verified by antimicrobial resistant test. Given its distinct genomic, morphological, and physiological differences from previously described type strains, strain LMIT005T is proposed as a representative of a novel genus of the family Cyclobacteriaceae, with the name Penaeicola halotolerans gen. nov., sp. nov. The type strain is LMIT005T (=KCTC 82616T=CICC 25047T).

Litoribacter populi sp. nov., isolated from the soil of a Populus euphratica forest.

A Gram-stain-negative, rod-shaped, and orange-pigmented bacterium, designated XAAS-A1T, was isolated from the soil of a Populus euphratica forest. The main respiratory quinone of XAAS-A1T is MK-7, and the principal cellular fatty acids are iso-C15:0, C17:1 ω6c, Iso-C17:0 3OH, and summed feature 3 (C16:1ω6c and/or C16:1ω7c). The major polar lipids are phosphatidylethanolamine, phosphatidylcholine, and two unidentified lipids. The 16S rRNA gene sequence analysis indicated that XAAS-A1T belongs to the genus Litoribacter within the family Cyclobacteriaceae, having the highest sequence similarities to Litoribacter ruber KCTC 22899T (97.1%) and L. alkaliphilus KCTC 32217T (96.9%). XAAS-A1T has a DNA G + C content of 42.1mol%. The orthoANI and the digital DNA-DNA hybridization values were markedly lower than the recommended threshold values of 96% and 70%. Phenotypic and genotypic data suggest that XAAS-A1T represents a novel species of the genus Litoribacter, for which we propose the name Litoribacter populi sp. nov. and XAAS-A1T (= CCTCC AB 2017159T = KCTC 62045T) as the type strain.

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).

Algoriphagus sanaruensis sp. nov., a member of the family Cyclobacteriaceae, isolated from a brackish lake in Hamamatsu, Japan.

Strain M8-2T, which was isolated from brackish lake water (Lake Sanaru) in Japan, was characterized for representation of a novel species in the genus Algoriphagus. Cells of strain M8-2T were aerobic, Gram-stain-negative and curved-rod-shaped (0.2-0.5 µm wide and 0.7-1.9 µm long). Strain M8-2T grew optimally at 30 °C, pH 6.5-7.5 and in the presence of 0.5-1.0 % (w/v) NaCl. MK-7 was the sole isoprenoid quinone. The major polar lipids were phosphatidylethanolamine, an unidentified phospholipid and an unidentified polar lipid. The predominant cellular fatty acids were iso-C15 : 0 and anteiso-C15 : 0. Phylogenetic analysis based on its 16S rRNA gene sequence showed that strain M8-2T belonged to the genus Algoriphagus and was closely related to Algoriphagus aquatilis A8-7T, Algoriphagus boseongensis BS-R1T, Algoriphagus aquaeductus T4T, Algoriphagus olei CC-Hsuan-617T, Algoriphagusshivajiensis NIO-S3T and Algoriphagus mannitolivorans DSM 15301T with sequence similarities of 96.6-97.4 %. Results of average nucleotide identity (<75 %) and digital DNA-DNA hybridization (<19 %) studies showed that M8-2T was distinct from its phylogenetic relatives. Based on the results of tests for acid production, the predominant cellular fatty acid composition, the DNA G+C content and phylogenetic position, a novel species in the genus Algoriphagus, with the name Algoriphagussanaruensis sp. nov., is proposed for strain M8-2T (=JCM 31446T=LMG 29969T).

Algoriphagus formosus sp. nov., isolated from coastal sediment.

A Gram-stain negative, facultative anaerobic, non-motile, strongly orange-pigmented and rod-shaped bacterium, designated XAY3209T, was isolated from a marine sediment sample collected from the coast of Weihai, China. Strain XAY3209T was found to grow optimally at 30°C, at pH 7.0 and in the presence of 2.0% (w/v) NaCl. Its genomic DNA G+C content was 41.9mol%. On the basis of 16S rRNA gene sequence similarity, the novel isolate belongs to the family Cyclobacteriaceae and is related to the genus Algoriphagus. It shares 98.1% 16S rRNA sequence identity with Algoriphagus marincola, its close phylogenetic relative, but did not show similarities more than 97% with other members of the genus Algoriphagus with validly published names. It contained menaquinone-7 (MK-7) as the sole respiratory quinone, iso-C15:0, iso-C17:1 ω9c and Summed feature 3 (C16:1 ω7c and/or iso-C15:0 2-OH) as the major fatty acids. The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, one unidentified phospholipid and five unidentified lipids. Results of physiological experiments, biochemical tests and genome average nucleotide identity value (with A. marincola MCCC 1F01203T) indicate that strain XAY3209T is genetically and phenotypically distinct from the species of the genus Algoriphagus with validly published names. Strain XAY3209T therefore represents a novel species, for which the name Algoriphagus formosus sp. nov. is proposed. The type strain is XAY3209T (=KCTC 52842T=MCCC 1H00189T).

Echinicola sediminis sp. nov., a marine bacterium isolated from coastal sediment.

A novel Gram-stain-negative, rod-shaped, gliding bacterium, designated strain 001-Na2T, was isolated from coastal sediment of the Yellow Sea in Sindu-ri, Republic of Korea. Cells were aerobic, oxidase-positive and catalase-positive. Colonies were dark salmon-coloured, circular, and pulvinate with entire margins. 16S rRNA gene sequence analysis revealed that strain 001-Na2T belonged to the genus Echinicola and these species formed a distinct lineage within the family Cyclobacteriaceae. The closest phylogenetic neighbours were 'Echinicola shivajiensis' AK12T (98.1 % 16S rRNA gene sequence similarity), Echinicola vietnamensis LMG 23754T (96.4 %), Echinicola jeungdonensis HMD 3054T (96.0 %), Echinicola pacifica KMM 6172T (96.0 %) and Echinicola rosea JL 3085T (95.8 %). The predominant respiratory quinone was menaquinone MK-7. The major fatty acids were iso-C15 : 0, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c), C17 : 1ω6c and summed feature 9 (comprising iso-C17 : 1ω9c and/or 10-methyl C16 : 0). The polar lipids were phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid and three unidentified lipids. The DNA G+C content was 44.6 mol%. DNA-DNA relatedness between strain 001-Na2T and 'E. shivajiensis' JCM 17847T was 20.8-21.1 %. On the basis of the phenotypic features, and phylogenetic and DNA-DNA hybridization analyses presented, strain 001-Na2T (=KCTC 52495T=JCM 31786T=DSM 103729T) is the type strain of a novel species of the genus Echinicola, for which the name Echinicola sediminis sp. nov. is proposed.

Mongoliibacter ruber gen. nov., sp. nov., a haloalkalitolerant bacterium of the family Cyclobacteriaceae isolated from a haloalkaline lake.

A novel haloalkalitolerant, rod-shaped bacterium, designated strain YIM 4-4T, was isolated from the surface water of the Dugerno lake, a haloalkaline lake in Inner Mongolia. The taxonomy of strain YIM 4-4T was investigated by a polyphasic approach. Strain YIM 4-4T was Gram-stain-negative, strictly aerobic, non-motile and formed red colonies. Optimal growth conditions were 28 °C, pH 8.0-11.0 and 0.5-2 % NaCl. The major respiratory quinone was menaquinone-7 (MK-7). The polar lipid profile was composed predominantly of phosphatidylethanolamine, six unidentified polar lipids, one phospholipid and one aminolipid. The predominant cellular fatty acids (>5 %) were iso-C15 : 0, iso-C17 : 1I/anteiso-C17 : 1B, iso-C16 : 1G, iso-C17 : 0 3-OH, C16 : 1ω7c/C16 : 1ω6c and iso-C16 : 1. The genomic DNA G+C content was 43.0 mol%. 16S rRNA gene sequence analysis indicated that the members of the genera Cecembia, Fontibacter, Aquiflexum and Indibacter of the family Cyclobacteriaceae (phylum Bacteroidetes) were the most closely related, with 16S rRNA gene sequence similarities ranging from 93.6 to 94.2 %. Other members of the family Cyclobacteriaceae showed sequence similarities < 93.0 %. On the basis of phenotypic, chemotaxonomic and phylogenetic properties, strain YIM 4-4T represents a novel species of a new genus, for which the name Mongoliibacter ruber gen. nov., sp. nov. is proposed. The type strain is YIM 4-4T ( = CCTCC AB 2012966T = DSM 27929T).

Negadavirga shengliensis gen. nov., sp. nov., a novel member of the family Cyclobacteriaceae isolated from oil-contaminated saline soil.

Four novel Gram-stain-negative, rod-shaped, and non-motile bacterial strains, SLG210-21(T), SLG210-4, SLG210-5 and SLG210-14, were isolated from oil-contaminated saline soil in Shengli Oilfield, China. Growth were observed at 25-42 °C (optimum 37 °C), in the presence of 0-10 % (w/v) NaCl (optimum 0-1 %) and at pH 4.0-10.0 (optimum pH 7.6-8.6). All the strains were positive for catalase and α, β-galactosidase activities and nitrogen reduction, and negative for oxidase activity, glucose fermentation and hydrolysis of agar, starch, gelatin, Tween 40, 60 and 80. The DNA G+C contents of the four strains were 41.3-43.0 mol% and the predominant respiratory quinones were all menaquinone-7. The major fatty acids were iso-C15:0, anteiso-C15:0, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), C16:1 ω5c and summed feature 9 (iso-C17:1 ω9c and/or 10-methyl C16:0), while the polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, glycolipid, two unidentified phospholipids and two unidentified amino lipids. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the four strains clustered together to form a stable branch in the family Cyclobacteriaceae, and were most closely related to the genera Cyclobacterium and Echinicola with the 16S rRNA gene sequence similarities being 88.6-90.3 and 89.6-91.4 %, respectively. DNA-DNA hybridization between SLG210-21(T) and the other three strains showed the relatedness of 93.8 ± 4.5, 96.2 ± 4.2 and 82.3 ± 4.8 %, respectively. Based on the polyphasic analysis, a novel species in a new genus, Negadavirga Shengliensis gen. nov., sp. nov., is proposed with SLG210-21(T) (=LMG 27737(T) = CGMCC1.12768(T)) [corrected] as the type strain.

Algoriphagus boseongensis sp. nov., a member of the family Cyclobacteriaceae isolated from a tidal flat

A Gram-stain negative, aerobic, non-motile, non-spore-forming and rod-shaped bacterial strain, BS-R1(T), was isolated from a tidal flat at Boseong, South Korea. Strain BS-R1(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 analyses based on 16S rRNA gene sequences revealed that strain BS-R1(T) belongs to the genus Algoriphagus, clustering consistently with the type strain of Algoriphagus mannitolivorans, with which it exhibited 98.4 % sequence similarity. Sequence similarities between strain BS-R1(T) and the type strains of the other Algoriphagus species were between 92.7 and 97.0 %. Strain BS-R1(T) was found to contain MK-7 as the predominant menaquinone and iso-C15:0, iso-C17:0 3-OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) as the major fatty acids. The major polar lipids of strain BS-R1(T) were identified as phosphatidylcholine, phosphatidylethanolamine and one unidentified lipid. The DNA G+C content was determined to be 42.3 mol% and its mean DNA-DNA relatedness values with A. mannitolivorans KACC 11349(T) was 17 ± 5 %. The phylogenetic and genetic distinctiveness and differential phenotypic properties demonstrated that strain BS-R1(T) is distinguishable from the other Algoriphagus species as well as A. mannitolivorans. On the basis of the data presented, strain BS-R1(T) is considered to represent a novel species of the genus Algoriphagus, for which the name Algoriphagus boseongensis sp. nov. is proposed. The type strain is BS-R1(T) (=KCTC 32580(T) = CECT 8446(T)).

Lunatimonas lonarensis gen. nov., sp. nov., a haloalkaline bacterium of the family Cyclobacteriaceae with nitrate reducing activity

Novel pinkish-orange pigmented, Gram-negative staining, half-moon shaped, non-motile, strictly aerobic strains designated AK24T and AK26 were isolated from water and sediment samples of Lonar Lake, Buldhana district, Maharahstra, India. Both strains were positive for oxidase, catalase and β-galactosidase activities. The predominant fatty acids were iso-C15:0 (41.5%), anteiso-C15:0 (9.7%), iso-C17:0 3OH (9.6%), iso-C17:1 ω9c (10.2%) and C16:1 ω7c/C16:1 ω6c/iso-C15:0 2OH (summed feature 3) (14.4%). The strains contained MK-7 as the major respiratory quinone, and phosphatidylethanolamine and five unidentified lipids as the polar lipids. Blast analysis of the 16S rRNA gene sequence of strain AK24T showed that it was closely related to Aquiflexum balticum, with a pair-wise sequence similarity of 91.6%, as well as to Fontibacter ferrireducens, Belliella baltica and Indibacter alkaliphilus (91.3, 91.2 and 91.2% pair-wise sequence similarity, respectively), but it only had between 88.6 and 91.0% pair-wise sequence similarity to the rest of the family members. The MALDI-TOF assay reported no significant similarities for AK24T and AK26, since they potentially represented a new species. A MALDI MSP dendrogram showed close similarity between the two strains, but they maintained a distance from their phylogenetic neighbors. The genome of AK24T showed the presence of heavy metal tolerance genes, including the genes providing resistance to arsenic, cadmium, cobalt and zinc. A cluster of heat shock resistance genes was also found in the genome. Two lantibiotic producing genes, LanR and LasB, were also found in the genome of AK24T. Strains AK24T and AK26 were very closely related to each other with 99.5% pair-wise sequence similarity. Phylogenetic analysis indicated that the strains were members of the family Cyclobacteriaceae and they clustered with the genus Mariniradius, as well as with the genera Aquiflexum, Cecembia, Fontibacter, Indibacter, and Shivajiella. DNA–DNA hybridization between strains AK24T and AK26 showed a relatedness of 82% and their rep-PCR banding patterns were very similar. Based on data from the current polyphasic study, it is proposed that the isolates be placed in a new genus and species with the name Lunatimonas lonarensis gen. nov., sp. nov. The type strain of Lunatimonas lonarensis is AK24T (=JCM 18822T=MTCC 11627T).

Cecembia lonarensis gen. nov., sp. nov., a novel haloalkalitolerant bacterium of the family Cyclobacteriaceae, isolated from a haloalkaline lake and emended descriptions of the genera Indibacter, Nitritalea, Belliella and Aquiflexum

Cecembia lonarensis gen. nov., sp. nov., a novel haloalkalitolerant bacterium of the family Cyclobacteriaceae, isolated from a haloalkaline lake and emended descriptions of the genera Indibacter, Nitritalea, Belliella and Aquiflexum

Mongoliitalea lutea gen. nov., sp. nov., an alkaliphilic, halotolerant bacterium isolated from a haloalkaline lake

Two bacterial isolates from the surface water of a haloalkaline lake on the Mongolia Plateau, strains MIM18(T) and MIM19, were characterized; their morphological, physiological and chemotaxonomic characters, and phylogenetic position based on 16S rRNA gene sequences, were determined. The two strains were alkaliphilic, halotolerant, non-motile, aerobic, Gram-negative, orange-red, rod-shaped and oxidase-positive. Growth was observed in 0-5.5% (w/v) NaCl, with optimum growth at 1%. The temperature range for growth was 0-41 °C, with good growth at 28-37 °C and optimum growth at 30-33 °C. The DNA G+C content was 39.8-41.2 mol%. The strains contained menaquinone MK-7 as the major respiratory quinone and phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine as the major polar lipids. Predominant cellular fatty acids were iso-C(15:0) (28.1-29.3%), iso-C(17:0) 3-OH (14.6-18.8%), C(15:1)ω6c (5.3-8.6%), C(14:0) 2-OH and/or iso-C(15:0) 2-OH (5.4-6.1%), and iso-C(17:1)ω9c and/or C(16:0) 10-methyl (5.0-6.8%). 16S rRNA gene sequence analysis showed that Belliella and Nitritalea of the family Cyclobacteriaceae were the closest related species with sequence similarities of 91.7-92.3% and 88.2%, respectively, with strains of these genera; other members of the Cyclobacteriaceae had sequence similarities lower than 88%. Phylogenetic analysis indicated that the strains formed a deep-rooted lineage distinct from the clades represented by the genera Belliella, Nitritalea, Indibacter, Aquiflexum, Echinicola, Litoribacter, Cyclobacterium and Algoriphagus. Based on the phenotypic and phylogenetic characteristics mentioned above, the two strains are representatives of a single novel species in a new genus; the name Mongoliitalea lutea gen. nov., sp. nov. is proposed, with MIM18(T) (=ACCC 05421(T)=KCTC 23224(T)) as the type strain.

Retraction. Cecembia lonarensis gen. nov., sp. nov., a novel haloalkalitolerant bacterium of the family Cyclobacteriaceae, isolated from a haloalkaline lake and emended descriptions of the genera Indibacter, Nitritalea, Belliella and Aquiflexum.

The authors would like to retract this publication in order to improve the chemotaxonomic data as it has become apparent that there are inconsistencies in the data presented in this paper. This paper has been retracted from IJSEM Papers in Press and will not be published in print in IJSEM.