The draft genome of Nitzschia closterium f. minutissima and transcriptome analysis reveals novel insights into diatom biosilicification.

BACKGROUND: Nitzschia closterium f. minutissima is a commonly available diatom that plays important roles in marine aquaculture. It was originally classified as Nitzschia (Bacillariaceae, Bacillariophyta) but is currently regarded as a heterotypic synonym of Phaeodactylum tricornutum. The aim of this study was to obtain the draft genome of the marine microalga N. closterium f. minutissima to understand its phylogenetic placement and evolutionary specialization. Given that the ornate hierarchical silicified cell walls (frustules) of diatoms have immense applications in nanotechnology for biomedical fields, biosensors and optoelectric devices, transcriptomic data were generated by using reference genome-based read mapping to identify significantly differentially expressed genes and elucidate the molecular processes involved in diatom biosilicification. RESULTS: In this study, we generated 13.81 Gb of pass reads from the PromethION sequencer. The draft genome of N. closterium f. minutissima has a total length of 29.28 Mb, and contains 28 contigs with an N50 value of 1.23 Mb. The GC content was 48.55%, and approximately 18.36% of the genome assembly contained repeat sequences. Gene annotation revealed 9,132 protein-coding genes. The results of comparative genomic analysis showed that N. closterium f. minutissima was clustered as a sister lineage of Phaeodactylum tricornutum and the divergence time between them was estimated to be approximately 17.2 million years ago (Mya). CAFF analysis demonstrated that 220 gene families that significantly changed were unique to N. closterium f. minutissima and that 154 were specific to P. tricornutum, moreover, only 26 gene families overlapped between these two species. A total of 818 DEGs in response to silicon were identified in N. closterium f. minutissima through RNA sequencing, these genes are involved in various molecular processes such as transcription regulator activity. Several genes encoding proteins, including silicon transporters, heat shock factors, methyltransferases, ankyrin repeat domains, cGMP-mediated signaling pathways-related proteins, cytoskeleton-associated proteins, polyamines, glycoproteins and saturated fatty acids may contribute to the formation of frustules in N. closterium f. minutissima. CONCLUSIONS: Here, we described a draft genome of N. closterium f. minutissima and compared it with those of eight other diatoms, which provided new insight into its evolutionary features. Transcriptome analysis to identify DEGs in response to silicon will help to elucidate the underlying molecular mechanism of diatom biosilicification in N. closterium f. minutissima.

Winogradskyella pelagia sp. nov., isolated from coastal sediment.

An orange-pigmented, Gram-stain-negative, strictly aerobic, non-flagellated and rod-shaped bacterium, designated strain DF17T, was isolated from coastal sediment collected from Jingzi Wharf, Weihai, PR China. The optimal growth conditions were determined to be at 30 °C, pH 7.5, and in 3 % (w/v) NaCl. According to phylogenetic analysis of the 16S rRNA gene sequence, strain DF17T showed the highest sequence similarity of 96.9 % to Winogradskyella aquimaris KCTC 23502T. The DNA G+C content was 35.8 mol%, and the major fatty acids were iso-C15 : 1 G, iso-C15 : 0, and iso-C17 : 0 3-OH. The major polar lipids were two aminoglycolipids, one phosphatidylethanolamine and four unidentified lipids. The predominant respiratory quinone was menaquinone-6 (MK-6). The average nucleotide identity, digital DNA-DNA hybridization, and amino acid identity values between strain DF17T and other Winogradskyella species were below the species delineation thresholds of 69.35-72.95 %, 16.9-19.6 % and 71.25-78.93 %, respectively. On the basis of its phenotypic, genetic and physiological characteristics, strain DF17T is suggested to represent a novel species of the genus Winogradskyella, for which the name Winogradskyella pelagia sp. nov. is proposed. The type strain is DF17T (MCCC 1H00456T=KCTC 82421T).

Aequorivita sediminis sp. nov. and Aequorivita marina sp. nov., isolated from marine sediment.

Two Gram-stain-negative, rod-shaped, non-motile, strictly aerobic strains, forming yellow colonies and designated F6058T and S2608T, were isolated from marine sediment collected in Weihai, PR China. Both strains grow at 4-40 °C (optimum, 30-33 °C), pH 6.0-7.5 (optimum, pH 6.5) and in the presence of 0-7.0 % (w/v) NaCl. The optimum NaCl concentrations for strains F6058T and S2608T were 2.0 % and 2.5 %, respectively. Phylogenetic analysis of the 16S rRNA gene sequences indicated that strains F6058T and S2608T share an evolutionary lineage with members of the genus Aequorivita. The isolates exhibited a 16S rRNA gene sequence similarity of 96.7 % to each other. Strains F6058T exhibited the highest 16S rRNA gene sequence similarity to Aequorivita xiaoshiensis F64183T (98.8 %), and S2608T was most similar to Aequorivita capsosiphonis A71T (96.9 %). Iso-C15:0, anteiso-C15:0 and iso-C17:0 3-OH were the major fatty acids of strains F6058T and S2608T. The sole respiratory quinone of both isolates was menaquinone 6 (MK-6). The polar lipid profiles of the isolates both consisted of phosphatidylethanolamine and phosphoglycolipids; however, strain F6058T exhibited one glycolipid, one aminolipid and two unidentified polar lipids, and strain S2608T also had two glycolipids and one unidentified polar lipid. The DNA G+C contents of strains F6058T and S2608T were 34.6 % and 37.7 mol%, respectively. Based on their phenotypic, chemotaxonomic and genomic characteristics, strains F6058T and S2608T were considered to represent novel species of the genus Aequorivita, for which the names Aequorivita sediminis sp. nov. and Aequorivita marina sp. nov. were proposed. The type strains are F6058T (=KCTC 92653T=MCCC 1H01358T) and S2608T (KCTC 92652T=MCCC 1H01361T).

Gilvimarinus gilvus sp. nov. and Gilvimarinus algae sp. nov., isolated from kelp seedlings.

Two novel rod-shaped, strictly aerobic, non-motile and Gram-stain-negative bacterial strains, designated SDUM040013T and SDUM040014T, were isolated from kelp seedlings in Weihai, PR China. Cells of strain SDUM040013T were 0.3-0.4 µm wide and 0.8-1.8 µm long, catalase-positive and oxidase-positive. Growth of SDUM040013T was observed at 0-37 °C (optimum, 28-30 °C) and pH 5.5-9 (optimum, pH 8.0) and in the presence of 1-8 % (w/v) NaCl (optimum, 2 %). The DNA G+C content of strain SDUM040013T was 50.5 %. Strain SDUM040013T showed the highest 16S rRNA gene sequence similarity (97.1 %) to Gilvimarinus chinensis. Cells of strain SDUM040014T were 0.4-0.5 µm wide and 1.0-1.4 µm long, catalase-positive and oxidase-positive. Growth of SDUM040014T was observed at 4-40 °C (optimum, 28-30 °C) and pH 5.5-9 (optimum, pH 8.5) and in the presence of 0-8 % (w/v) NaCl (optimum, 2 %). The DNA G+C content of strain SDUM040014T was 56.5 %. Strain SDUM040014T showed the highest 16S rRNA gene sequence similarity (96.2%) to Gilvimarinus polysaccharolyticus. The isoprenoid quinone of both strains was Q-8 and the predominant fatty acids were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c) and C16 : 0. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were the major polar lipids. Given these phenotypic and chemotaxonomic properties, as well as phylogenetic data, strains SDUM040013T and SDUM040014T were considered to represent two novel species of the genus Gilvimarinus, for which the names Gilvimarinus gilvus sp. nov. and Gilvimarinus algae sp. nov. are proposed. The type strains are SDUM040013T (=KCTC 8123T=MCCC 1H01413T) and SDUM040014T (=KCTC 8124T=MCCC 1H01414T), respectively.

Oerskovia flava sp. nov., a deoxynivalenol (DON)-degrading actinomycete isolated from the rhizosphere soil of long-term continuous cropping cucumber.

The deoxynivalenol (DON)-degrading bacterium JB1-3-2 T was isolated from a rhizosphere soil sample of cucumber collected from a greenhouse located in Zhenjiang, Eastern China. The JB1-3-2 T strain is a Gram-stain-positive, nonmotile and round actinomycete. Growth was observed at temperatures between 15 and 40 ℃ (optimum, 35 ℃), in the presence of 15% (w/v) NaCl (optimum, 3%), and at pH 3 and 11 (optimum, 7). The major cellular fatty acids identified were anteiso-C15:0, iso-C16:0 and anteiso-C17:0. Genome sequencing revealed a genome size of 4.11 Mb and a DNA G + C content of 72.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the JB1-3-2 T strain was most closely related to type strains of the Oerskovia species, with the highest sequence similarity to Oerskovia turbata NRRL B-8019 T (98.2%), and shared 98.1% sequence identity with other valid type strains of this genus. Digital DNA‒DNA hybridization (dDDH) and average nucleotide identity (ANI) showed 21.8-22.2% and 77.2-77.3% relatedness, respectively, between JB1-3-2 T and type strains of the genus Oerskovia. Based on genotypic, phylogenetic, chemotaxonomic, physiological and biochemical characterization, Oerskovia flava, a novel species in the genus Oerskovia, was proposed, and the type strain was JB1-3-2 T (= CGMCC 1.18555 T = JCM 35248 T). Additionally, this novel strain has a DON degradation ability that other species in the genus Oerskovia do not possess, and glutathione-S-transferase was speculated to be the key enzyme for strain JB1-3-2 T to degrade DON.

Nocardioides limicola sp. nov., an alkaliphilic alkane degrading bacterium isolated from oilfield alkali-saline soil.

A Gram-stain-positive, rod-shaped, non-spore-forming, alkane degrading bacterium, designated DJM-14T, was isolated from oilfield alkali-saline soil in Heilongjiang, Northeast China. On the basis of 16 S rRNA gene sequencing, strain DJM-14T was shown to belong to the genus Nocardioides, and related most closely to Nocardioides terrigena KCTC 19,217T (95.53% 16 S rRNA gene sequence similarity). Strain DJM-14T was observed to grow at 25-35 °C, pH 7.0-11.0, in the presence of 0-6.0% (w/v) NaCl. The predominant respiratory quinone was MK-8 (H4) and LL-diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan. The major fatty acids were identified as iso-C16:0 and C18:1 ω9c. It contained diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol as the polar lipids. The genome (3,722,608 bp), composed of 24 contigs, had a G + C content of 69.6 mol%. Out of the 3667 predicted genes, 3618 were protein-coding genes, and 49 were ncRNAs. Digital DNA-DNA hybridization (dDDH) estimation and average nucleotide identity (ANI) of strain DJM-14T against genomes of the type strains of related species in the same family ranged between 18.7% and 20.0%; 68.8% and 73.6%, respectively. According to phenotypic, genotypic and phylogenetic data, strain DJM-14T represents a novel species in the genus Nocardioides, for which the name Nocardioides limicola sp. nov. is proposed and the type strain is DJM-14T (= CGMCC 4.7593T, =JCM 33,692T). In addition, novel strains were able to grow with n-alkane (C24-C36) as the sole carbon source. Multiple copies of alkane 1-monooxygenase (alkB) gene, as well as alcohol dehydrogenase gene and aldehyde dehydrogenase gene involved in the alkane assimilation were annotated in the genome of type strain DJM-14T.

Genome sequencing provides insights into the evolution of gene families encoding plant cell wall-degrading enzymes in longhorned beetles.

With more than 36,000 species, the longhorned beetles (family Cerambycidae) are a mega-diverse lineage of mostly xylophagous insects, all of which are represented by the sole sequenced genome of the Asian longhorned beetle (Anoplophora glabripennis; Lamiinae). Their successful radiation has been linked to their ability to degrade plant cell wall components using a range of so-called plant cell wall-degrading enzymes (PCWDEs). Our previous analysis of larval gut transcriptomes demonstrated that cerambycid beetles horizontally acquired genes encoding PCWDEs from various microbial donors; these genes evolved through multiple duplication events to form gene families. To gain further insights into the evolution of these gene families during the Cerambycidae radiation, we assembled draft genomes for four beetle species belonging to three subfamilies using long-read nanopore sequencing. All the PCWDE-encoding genes we annotated from the corresponding larval gut transcriptomes were present in these draft genomes. We confirmed that the newly discovered horizontally acquired glycoside hydrolase family 7 (GH7), subfamily 26 of GH43 (GH43_26), and GH53 (all of which are absent from the A. glabripennis genome) were indeed encoded by these beetles' genome. Most of the PCWDE-encoding genes of bacterial origin gained introns after their transfer into the beetle genome. Altogether, we show that draft genome assemblies generated from nanopore long-reads offer meaningful information to the study of the evolution of gene families in insects. We anticipate that our data will support studies aiming to better understand the biology of the Cerambycidae and other beetles in general.

Draft genome sequence and comparative genomic analysis of Penicillium pancosmium MUM 23.27 isolated from raw honey.

The draft genome sequence and main genomic features of Penicillium pancosmium MUM 23.27, isolated from Portuguese raw honey are reported. The genome size is 34.82 Mb, containing a 48.99% GC content, 11,394 genes, with 39 rRNAs and 147 tRNAs/tmRNAs. Twenty-six BGCs were predicted with four exhibiting significant similarities with YWA1, chaetoglobosin A/chaetoglobosin C, squalestatin S1, and nidulanin A. Moreover, the whole-genome sequencing and in silico genomic analysis, allowed to further understand some aspects of this species habitat, resistance, and evolutionary genomic events. Altogether, the results obtained also allow to dwell deeper on particular Penicillia biological characteristics and genomic traits, permitting them to thrive in these honey substrates. In addition, this resource represents the first genome for the species and one of the first for raw honeys filamentous fungi.

Aliidiomarina quisquiliarum sp. nov., isolated from landfill leachate.

Bacterial strain Y-6T, isolated from a landfill site in Yiwu, PR China, was characterized using a polyphasic taxonomy approach. Cells were Gram-stain-negative, aerobic, rod-shaped, motile by means of a single polar flagellum and formed pale beige colonies. Strain Y-6T grew at 4-40 °C (optimal at 30-37 °C), pH 6.5-9.5 (optimal at pH 7.2-8.5) and in the presence of 0.5-10.0 % (w/v) NaCl (optimal at 1.0-3.0 %). Phylogenetic analysis revealed that strain Y-6T was a member of the genus Aliidiomarina and closely related to Aliidiomarina taiwanensis MCCC 1A06493T with a 16S rRNA sequence similarity of 98.2 %. The major cellular fatty acids of the isolate were iso-C15 : 0, C16 : 0, iso-C17 : 0 and summed feature 9 (iso-C17 : 1 ω9c and/or 10-methyl-C16 : 0). Q-8 was the predominant ubiquinone. The major polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, aminoglycophospholipid, aminophospholipid, phospholipid, three glycolipids and two unknown lipids. The genomic DNA G+C content was 46.6 mol%. The digital DNA-DNA hybridization value between Y-6T and A. taiwanensis MCCC 1A06493T was 18.3 %. Strain Y-6T had an average nucleotide identity value of 74.09 % with A. taiwanensis MCCC 1A06493T. Results from the polyphasic taxonomy study support the conclusion that strain Y-6T represents a novel Aliidiomarina species, for which the name Aliidiomarina quisquiliarum sp.nov. is proposed. The type strain is Y-6T (=MCCC 1K06228T=KCTC 82676T).

Pontibacterium sinense sp. nov., a nitrate-reducing and thiosulphate-oxidizing bacterium, isolated from coastal sediment.

A novel bacterial strain, N1Y112T, was isolated from coastal sediment collected in Weihai, PR China. This Gram-stain-negative, facultatively anaerobic, motile rod-shaped bacterium exhibited the ability to oxidize thiosulphate to sulphate and reduce nitrate to ammonia through its Sox system and nitrate reduction pathway, respectively. The strain grew at 20-35 °C (optimum, 28 °C), pH 6.0-10.0 (optimum, pH 7.5) and in the presence of 1.0-5.0 % (w/v) NaCl (optimum, 3.0 %). Major fatty acids present in the strain included summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c), summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c) and C16 : 0. Its polar lipid profile consisted of one phosphatidylethanolamine, two unknown aminolipids, one aminophosphoglycolipid, one diphosphatidylglycerol, one phosphatidylglycerol, two unknown phospholipids and two unknown lipids. Strain N1Y112T contained ubiquinone-7 and ubiquinone-8 as isoprenoid quinones, with a genomic G+C content of 50.6 mol%. Based on phylogenetic analysis, strain N1Y112T clustered with Pontibacterium granulatum JCM 30316T being its closest relative at 97.1 % 16S rRNA gene sequence similarity. The average nucleotide identity and digital DNA-DNA hybridization values were 77.1 and 20.7 %, respectively, which suggest significant differences between genomes of N1Y112T and P. granulatum JCM 30316T. Based on the findings from its phenotypic, genotypic and phylogenetic analyses, N1Y112T is considered to represent a novel species of the genus Pontibacterium, for which the name Pontibacterium sinense sp. nov. is proposed. The type strain is N1Y112T (=KCTC 72927T=MCCC 1H00429T).

Aliiroseovarius subalbicans sp. nov. and Aliiroseovarius sediminis sp. nov., isolated from marine sediment.

Two novel strains (N1Y82T and N1F302T) were isolated from a marine sediment sample taken from the coastal zone of Weihai, PR China. Cells of the two strains were Gram-strain-negative, catalase-positive, oxidase-positive, non-motile and ovoid- to rod-shaped. Strain N1Y82T grew optimally at 16 °C, pH 7.5 and in the presence of 3.0 % (w/v) NaCl. Strain N1F302T grew optimally at 28 °C, pH 7.0-7.5 and in the presence of 2.0-2.5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that strains N1Y82T and N1F302T belonged to the genus Aliiroseovarius, and were mostly related to Aliiroseovarius sediminilitoris KCTC 23959T with sequence similarity of 96.5 and 97.1 %, respectively. For these two novel strains, C18 : 1 ω7c was the major fatty acid, ubiquinone 10 was the predominant respiratory quinone, and phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, one unidentified aminolipid and one unidentified phospholipid were the major polar lipids. The DNA G+C contents of strain N1Y82T and N1F302T were 61.3 and 59.0 %, respectively. Consequently, strains N1Y82T and N1F302T are considered to represent two novel species of the genus Aliiroseovarius, for which the names Aliiroseovarius subalbicans sp. nov. and Aliiroseovarius sediminis sp. nov. are proposed. The type strains are N1Y82T (=KCTC 82768T=MCCC 1H00524T) and N1F302T (=KCTC 82412T=MCCC 1H00525T), respectively.

Runella salmonicolor sp. nov. and Dyella lutea sp. nov., isolated from paddy field soil.

Bacterial strains were collected from the soil of a paddy field around Dongguk University in Goyang, Republic of Korea. Two Gram-stain-negative, rod-shaped, aerobic or facultatively anaerobic bacterial strains were designated S5T and SaT. The results of analysis of phylogenetic trees based on 16S rRNA and whole-genome sequences indicated that these two strains represented a member of the genus Runella and a member of the genus Dyella, respectively. S5T exhibited 99.22, 98.10 and 97.68 % similarity to Runella rosea HYN0085T, Runella aurantiaca YX9T and Runella slithyformis DSM 19594T, respectively. S5T grew at 15-40 °C (optimum, 25 °C), at pH 6.5-12.0 (optimum, pH 9.5) and in the presence of 0-0.5 % (w/v) NaCl (optimum, 0 %). SaT exhibited 99.18 %, 98.36 %, 97.82 % and 97.68 % similarity to Dyella thiooxydans ATSB10T, Frateruia defendens DHoT, Fulvimonas yonginensis 5HGs31-2T and Dyella ginsengisoli Gsoil 3046T, respectively, and grew at 20-40 °C (optimum, 30 °C), at pH 5.5-11.0 (optimum, pH 8) and in the presence of 0-4.5 % (w/v) NaCl (optimum, 2.5 %). The average nucleotide identity difference values of S5T, SaT and the species reference strains were 92.16-93.62 % and 92.71-93.43%, which confirms that the S5T and SaT represent two novel species of the genera Runella and Dyella, respectively. The draft genome of S5T consisted of 7 048 502 bp, with a DNA G+C content of 44.9 % and that of SaT of 4 398 720 bp with a DNA G+C content of 67.9 %. The phylogenetic, phenotypic and physiological characteristics permitted the distinction of the two strains from their families, and we thus propose the names Runella salmonicolor sp. nov. (type strain S5T = KACC 22689T = TBRC 16343T) and Dyella lutea sp. nov. (type strain SaT=KACC 22690T = TBRC 16344T).

Roseateles albus sp. nov., Roseateles koreensis sp. nov. and Janthinobacterium fluminis sp. nov., isolated from freshwater at Jucheon River, and emended description of Roseateles aquaticus comb. nov.

Three Gram-stain-negative, facultatively anaerobic, rod-shaped, catalase-positive, oxidase-negative bacterial strains were designated as hw1T, hw8T and hw3T. Strains hw1T, hw8T and hw3T grew at 15-28 °C (optimum, 25 °C), 15-35 °C (optimum, 30 °C) and 4-28 °C (optimum, 20 °C), respectively, and at pH 7.0-12.0 (optimum, pH 9.0), pH 6.0-11.0 (optimum, pH 9.0) and 5.0-12.0 (optimum, pH 7.0), respectively. Additionally, strains hw1T and hw8T only grew when the NaCl concentration was 0 %, while strain hw3T grew at between 0 and 0.5 % (w/v; optimum, 0 %). The average nucleotide identity (ANI) values between strains hw1T, hw8T and the Roseateles type strains ranged from 73.8 to 84.2 %, while the digital DNA-DNA hybridization (dDDH) values ranged from 19.7 to 27.5 %. The ANI values between strain hw3T and the Janthinobacterium type strains ranged from 78.7 to 80.7 %, while dDDH values ranged from 22.3 to 23.0 %. The draft genomes of strains hw1T, hw8T and hw3T consisted of 5.5, 4.4 and 5.9 Mbp, with DNA G+C contents of 61.7, 61.8 and 66.0 mol%, respectively. The results of the dDDH, ANI, phylogenetic, biochemical and physiological analyses indicated that the novel strains were distinct from other members of their genera. Thus, we proposed the names Roseateles albus sp. nov. (type strain hw1T= KACC 22887T= TBRC 16613T), Roseateles koreensis sp. nov. (type strain hw8T= KACC 22885T= TBRC 16614T) and Janthinobacterium fluminis sp. nov. (type strain hw3T= KACC 22886T= TBRC 16615T).

Alteromonas gilva sp. nov. and Erythrobacter fulvus sp. nov., isolated from a tidal mudflat.

Strains chi3T and sf7T were collected from a tidal mudflat around Dongmak beach in Ganghwa, Republic of Korea. Both strains were Gram-stain-negative, aerobic or facultatively anaerobic, and rod-shaped. Results of phylogenetic tree analysis based on 16S rRNA and whole-genome sequences suggested that strains chi3T and sf7T belong to the genera Alteromonas and Erythrobacter, respectively. The cells of strain chi3T were non-motile and grew at 15-45 °C (optimum, 38 °C), at pH 6.0-10.0 (optimum, pH 8.0) and in the presence of 0-9.0 % (w/v) NaCl (optimum, 2.0 %). The cells of strain sf7T were motile as they had flagella and grew at 20-48 °C (optimum, 38 °C), at pH 6.0-10.0 (optimum, pH 9.0) and in the presence of 0-5.0 % (w/v) NaCl (optimum, 1.0 %). Strains chi3T and sf7T have average nucleotide identity values (70.0-70.4% and 78.9-81.7 %) and digital DNA-DNA hybridization values (21.8-22.3% and 21.0-25.6 %) with reference strains in the genera Alteromonas and Erythrobacter, respectively. Data from digital DNA-DNA hybridization, as well as phylogenetic, biochemical and physiological analyses, indicated the distinction of the two strains from the genera Alteromonas and Erythrobacter, respectively, and we thus propose the names Alteromonas gilva sp. nov. (type strain chi3T=KACC 22866T=TBRC 16612T) and Erythrobacter fulvus sp. nov. (type strain sf7T=KACC 22865T=TBRC 16611T).

Isolation and characterization of a novel glycoside hydrolase positive bacterial strain named Terrimonas ginsenosidimutans sp. nov. with ginsenoside-converting activity.

A novel yellow-pigmented catalase- and oxidase-positive bacterial strain (designated NA20T) was isolated from wetland soil and characterized. Results of 16S rRNA and draft genome sequence analysis placed strain NA20T within the genus Terrimonas of the family Chitinophagaceae. Strain NA20T showed ≤97.1 % sequence similarity to members of the genus Terrimonas and the highest sequence similarity was found to Terrimonas lutea DYT (97.1%). The draft genome of strain NA20T had a total length of 7 144 125 base pairs. A total of 5659 genes were identified, of which 5613 were CDS and 46 RNA genes were assigned a putative function. Mining the genomes revealed the presence of 225 carbohydrate genes out of 1334 genes. Strain NA20T contained iso-C15 : 0, iso-C15 : 0 G, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) as major fatty acids. The predominant quinone was MK-7. The major polar lipids were phosphatidylethanolamine, one unknown polar lipid and one unknown aminophospholipid. Additionally, the functional analysis of NA20T showed the conversion of protopanaxatriol-mix type major ginsenosides (Rb1, Rc and Rd) to minor ginsenosides F2 and weak conversion of Rh2 and C-K within 24 h. As a result, the genotypic, phenotypic and taxonomic analyses support the affiliation of NA20T within the genus Terrimonas, for which the name Terrimonas ginsenosidimutans sp. nov. is proposed. The type strain is NA20T (=KACC 22218T=LMG 32198T).

Characterization of four novel bacterial species of the genus Sphingomonas, Sphingomonas anseongensis, Sphingomonas alba, Sphingomonas brevis and Sphingomonas hankyongi sp.nov., isolated from wet land.

Four novel bacterial strains, designated as RG327T, SE158T, RB56-2T and SE220T, were isolated from wet soil in the Republic of Korea. To determine their taxonomic positions, the strains were fully characterized. On the basis of genomic information (16S rRNA gene and draft genome sequences), all four isolates represent members of the genus Sphingomonas. The draft genomes of RG327T, SE158T, RB56-2T and SE220T consisted of circular chromosomes of 2 226 119, 2 507 338, 2 593 639 and 2 548 888 base pairs with DNA G+C contents of 64.6, 63.6, 63.0 and 63.1 %, respectively. All the isolates contained ubiquinone Q-10 as the predominant quinone compound and a fatty acid profile with C16 : 0, C17 : 1ω6c, C18 : 1 2-OH, summed feature 3 (C16 : 1ω7c/C16 : 1ω6c) and summed feature 8 (C18 : 1ω7c/C18 : 1ω6c) as the major fatty acids, supporting the affiliation of strains RG327T, SE158T, RB56-2T and SE220T to the genus Sphingomonas. The major identified polar lipids in all four novel isolates were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid and phosphatidylcholine. Moreover, the physiological, biochemical results and low level of DNA-DNA relatedness and average nucleotide identity values allowed the phenotypic and genotypic differentiation of RG327T, SE158T, RB56-2T and SE220T from other species of the genus Sphingomonas with validly published names and indicated that they represented novel species of the genus Sphingomonas, for which the names Sphingomonas anseongensis sp. nov. (RG327T = KACC 22409T = LMG 32497T), Sphingomonas alba sp. nov. (SE158T = KACC 224408T = LMG 324498T), Sphingomonas brevis (RB56-2T = KACC 22410T = LMG 32496T) and Sphingomonas hankyongi sp. nov., (SE220T = KACC 22406T = LMG 32499T) are proposed.

Genomes comparison of two Proteus mirabilis clones showing varied swarming ability.

BACKGROUND: Proteus mirabilis is a Gram-negative bacteria most noted for its involvement with catheter-associated urinary tract infections. It is also known for its multicellular migration over solid surfaces, referred to as 'swarming motility'. Here we analyzed the genomic sequences of two P. mirabilis isolates, designated K38 and K39, which exhibit varied swarming ability. METHODS AND RESULTS: The isolates genomes were sequenced using Illumina NextSeq sequencer, resulting in about 3.94 Mbp, with a GC content of 38.6%, genomes. Genomes were subjected for in silico comparative investigation. We revealed that, despite a difference in swarming motility, the isolates showed high genomic relatedness (up to 100% ANI similarity), suggesting that one of the isolates probably originated from the other. CONCLUSIONS: The genomic sequences will allow us to investigate the mechanism driving this intriguing phenotypic heterogeneity between closely related P. mirabilis isolates. Phenotypic heterogeneity is an adaptive strategy of bacterial cells to several environmental pressures. It is also an important factor related to their pathogenesis. Therefore, the availability of these genomic sequences will facilitate studies that focus on the host-pathogen interactions during catheter-associated urinary tract infections.

Unveiling the genomic potential of a novel thermostable glycoside hydrolases producing Neobacillus sedimentimangrovi UE25.

Genetic and enzymatic potential of Neobacillus sedimentimangrovi has not been assembled to date. Here, we report a high-quality genome assembly of thermophilic bacterium Neobacillus sedimentimangrovi UE25 using Illumina Hi-seq 2500. The strain was isolated from a crocodile pond Manghopir, Karachi, Pakistan. QUAST quality parameters showed 37.75% GC content and exhibited the genome into 110 contigs, with a total size of 3,230,777 bases. Genome of N. sedimentimangrovi UE25 harbors phage mediated DNA through horizontal gene exchange from the phages, symbiotic and pathogenic bacteria. Most of the phage genome encodes for hypothetical proteins, protease, and phage assembly proteins. Gene clusters encoding the intrinsic resistance to glycopeptides, isoniazid, rifamycin, elfamycin, macrolide, aminoglycosides, tetracycline and fluoroquinolone were identified into the genome. Since, the strain has been reported for the production of many industrially important thermostable enzymes, therefore, the genomic data of thermostable enzymes might be helpful to employ this species in commercial sectors. Probing genes of multiple thermostable glycoside hydrolase enzymes especially xylanases of N. sedimentimangrovi UE25 showed genetic diversity among the genes and confer the industrial importance of this microorganism. Furthermore, the genome of N. sedimentimangrovi will greatly improve our understanding of its genetics and evolution.

Draft Genome Sequence of Carrot Alternaria Leaf Blight Pathogen Alternaria dauci.

The fungal genus Alternaria, which causes a variety of crop diseases, is widely distributed in the world. Alternaria leaf blight, caused by Alternaria dauci, is one of the most common and destructive diseases in carrot. The infection of A. dauci leads to dramatic decay on both foliage and taproot in severe cases, which results in significant yield losses. In this study, we sequenced and assembled the genome of A. dauci isolate CALB1, which isolated from the major carrot producing areas of China. A total of 65 contigs were assembled, and the estimated genome size was 34.9 Mb. The draft genome of A. dauci can be used for comparative genomic analysis of Alternaria species and provide genetic information for further research on plant-pathogen interactions.

Draft Genome Sequence of the Fluconazole-Resistant Candida palmioleophila Clinical Isolate CBS 18098.

Candida palmioleophila belongs to the Saccharomycetales. This opportunistic yeast which has been associated with invasive infections in human and animals, warrants a specific attention as it is frequently misidentified and display reduced susceptibility to fluconazole. Here, we report the first draft genome of C. palmioleophila, obtained from a clinical isolate.