- Volume 70, Issue 2, 2020

A phototrophic bacterium, designated as strain JA983T, was isolated from a freshwater pond in Gujarat, India. The strain was yellowish brown, catalase- and oxidase-positive, rod-to-oval shaped, Gram-stain-negative and motile. Growth was observed at 20–35 °C. NaCl was not required for optimum growth and up to 5 % was tolerated. Growth was observed at pH 6.0–8.0, with an optimum at pH 7.0. An unidentified glycolipid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, two unidentified aminolipids (AL1, AL2) and two unidentified lipids (L1 and L2) are the polar lipids of JA983T. Q10 is the only quinone. C18 : 1 ω7c/C18 : 1 ω6c is the major fatty acid. JA983T showed highest 16S rRNA gene sequence similarity with the type strains of Rhodobacter sphaeroides (98.99%), Rhodobacter megalophilus (98.99 %), Rhodobacter johrii (98.99 %) and other members of the genus Rhodobacter with less than 98.7 % similarity. In a 16S rRNA gene sequence-based phylogenetic tree, JA983T formed a different sub-clade with its nearest phylogenetic members of genus Rhodobacter . Phenotypic, chemotaxonomic, phylogenetic and genomic [average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) differences indicated that JA983T is significantly different from other species of the genus Rhodobacter and thus represents a novel species of the genus for which the name Rhodobacter sediminicola sp. nov. is proposed. The type strain is JA983T (=KCTC 15782T=NBRC 113843T).

A Gram-staining-negative, aerobic, curved rod-shaped and thermophilic bacterial strain, designated YIM 72297T, was isolated from a sediment sample collected from a hot spring in Tengchong county, Yunnan province, south-west China. Growth was observed at pH 5.0–9.0 with an optimum of pH 7.0–7.5, and at 45–60 °C with an optimum of 55 °C. Positive for catalase and oxidase. The 16S rRNA gene sequence comparison indicated that strain YIM 72297T was most closely related to Elioraea tepidiphila DSM 17972T (96.9 %) and showed <91 % sequence similarities to members of the order Rhodospirillales . Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YIM 72297T formed a distinct lineage within the genus Elioraea , and revealed that the genus Elioraea formed a novel family-level clade in the order Rhodospirillales . The ANI and the dDNA-DNA hybridization estimate values between strains YIM 72297T and Elioraea tepidiphila DSM 17972T were 70.8 and 20.1 %, respectively. Strain YIM 72297T contained Q-10 as the predominant ubiquinone. The major fatty acids (>5 %) were summed C18 : 0 (35.8 %), summed feature 8 (30.1 %), C16 : 0 (12.6 %), C18 : 1 2OH (5.6 %) and C16 : 0 2OH (5.4 %). The polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, diphosphosphatidylglycerol and phosphatidylglycerol in addition to two unidentified aminolipids. The DNA G+C content of YIM 72297T was 70.8 mol% (draft genome). On the basis of the polyphasic taxonomic evidence presented in this study, strain YIM 72297T should be classified as representing a novel species of the genus Elioraea , for which the name Elioraea thermophila sp. nov. is proposed, with the type strain YIM 72297T (=CCTCC AB 2017169T=KCTC 62323T). In addition, a novel family, Elioraeaceae fam. nov., is proposed to accommodate the genus Elioraea .

The taxonomic status of all Pseudocitrobacter species was re-evaluated by comparative genomics based on whole genome sequencing. As a result, it is obvious that Pseudocitrobacter anthropi is a later heterotypic synonym of Pseudocitrobacter faecalis . In addition, genome-based analysis of strain CPO20170097T, isolated from a patient in northern Denmark was allocated to the genus Pseudocitrobacter . This strain showed significant genotypic and phenotypic differences from P. faecalis and it is proposed that this strain represents a novel species of the genus, for which the name Pseudocitrobacter vendiensis sp. nov. is proposed with the type strain CPO20170097T (=CCUG 73096T=LMG 31042T).

A novel Gram-stain-negative, aerobic, non-spore-forming, non-motile and rod-shaped bacterial strain, DHC34T, was isolated from forest soil of Dinghushan Biosphere Reserve, Guangdong Province, China (112° 31′ E 23° 10′ N). It grew optimally on R2A medium at 28 °C, at pH 6.0–7.0 and in the presence of 0–1 % (w/v) NaCl. Strain DHC34T was closely related to Burkholderia alpina LMG 28138T (98.5 % 16S rRNA gene sequence similarity). 16S rRNA gene sequence analysis showed that strain DHC34T formed a clade with B. alpina LMG 28138T, which is next to but branched deeply with Robbsia andropogonis ICMP 2807T. The phylogenetic relationships among these three strains were also supported with the phylogram based on concatenated partial gyrB, recA and trpB gene sequences. The phylogenomic tree generated with the UBCG tool showed that strains DHC34T and R. andropogonis ICMP 2807T were in a different clade. The DNA–DNA relatedness values between strain DHC34T and B. alpina LMG 28138T and R. andropogonis ICMP 2807T were much lower than 70 %. Strain DHC34T contained ubiquinone 8 as the major respiratory quinone. Its major fatty acids were C16 : 0, C17 : 0 cyclo and C19 : 0 cyclo ω8c. The DNA G+C content of strain DHC34T was 64.2 mol%. The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, three unidentified aminophospholipids, four unidentified phospholipids, one unidentified aminolipid and a polar lipid. The phenotypic, phylogenetic, genotypic and chemotaxonomic data showed that strain DHC34T represents a novel species of a new genus in the family Burkholderiaceae , for which the name Pararobbsia silviterrae gen. nov., sp. nov. is proposed. The type strain of Pararobbsia silviterrae is DHC34T (=KCTC 42628T=LMG 28845T). On the basis of the current data, Burkholderia alpina is renamed as Pararobbsia alpina comb. nov.

For many smallholder farmers of Sub-Saharan Africa, pigeonpea (Cajanus cajan) is an important crop to make ends meet. To ascertain the taxonomic status of pigeonpea isolates of Côte d’Ivoire previously identified as bradyrhizobia, a polyphasic approach was applied to strains CI-1BT, CI-14A, CI-19D and CI-41S. Phylogeny of 16S ribosomal RNA (rRNA) genes placed these nodule isolates in a separate lineage from current species of the B. elkanii super clade. In phylogenetic analyses of single and concatenated partial dnaK, glnII, gyrB, recA and rpoB sequences, the C. cajan isolates again formed a separate lineage, with strain CI-1BT sharing the highest sequence similarity (95.2 %) with B. tropiciagri SEMIA 6148T. Comparative genomic analyses corroborated the novel species status, with 86 % ANIb and 89 % ANIm as the highest average nucleotide identity (ANI) values with B. elkanii USDA 76T. Although CI-1BT, CI-14A, CI-19D and CI-41S shared similar phenotypic and metabolic properties, growth of CI-41S was slower in/on various media. Symbiotic efficacy varied significantly between isolates, with CI-1BT and CI-41S scoring on the C. cajan ‘Light-Brown’ landrace as the most and least proficient bacteria, respectively. Also proficient on Vigna radiata (mung bean), Vigna unguiculata (cowpea, niébé) and additional C. cajan cultivars, CI-1BT represents a potential bioinoculant adapted to local soil conditions and capable of fostering the growth of diverse legume crops in Côte d'Ivoire. Given the data presented here, we propose the 19 C. cajan isolates to belong to a novel species called Bradyrhizobium ivorense sp. nov., with CI-1BT (=CCOS 1862T=CCMM B1296T) as a type strain.

Strain SY-07 was isolated from decaying leaves of Avicennia marina collected from Syhat mangroves, Dammam city, Arabian Gulf, Saudi Arabia. Phylogenetic analyses of three genes [D1/D2 region of the LSU and SSU rRNA genes and internal transcribed spacer (ITS) region] showed that strain SY-07 represents a novel species of the genus Saturnispora distinct from closely related species. Saturnispora mendoncae was the most closely related species with an LSU gene sequence similarity of 89.3 % (58 nucleotide substitutions and four indels out of 578 nt), 97 % similarity for the SSU gene (42 nucleotide substitutions and 10 indels out of 1614 nt) and 88 % similarity for the ITS region (15 nucleotide substitutions and eight indels out of 430 nt). In addition, strain SY-07 differed from S. mendoncae by its ability to assimilate d-galactose (weak), d-xylose (weak), meso-erythritol (delayed), glucono-δ-lactone, citrate (delayed) and ethylamine. S. mendoncae produced persistent asci that contain two to four spherical ascospores and lacked pseudohyphae, while sexual reproduction was not observed in strain SY-07 and extensive and pseudohyphae were present. Strain SY-07 was able to grow at between 25 and 40 °C, while S. mendoncae did not grow at 37 °C. The name Saturnispora mangrovi f.a., sp. nov. is proposed for strain SY-07. The holotype is CBS 15874, with the ex-type culture AUMC 12005. The MycoBank number for Saturnispora mangrovi f.a., sp. nov. is MB 827036.

A total of 21 yeast isolates were recovered as part of a research project on biodiversity of yeasts in traditional dairy products in Alborz province, Iran. Standard protocols were used to carry out phenotypic, biochemical, physiological characterization and the phylogenetic analysis of combined the D1/D2 domain of the large ribosomal subunit (26S or LSU) and ITS region sequences. Five strains represented a potential new ascomycetous yeast species. Ascospore formation was not observed in these strains, and they did not ferment the examined carbon sources. Phylogenetic analysis placed these isolates in a well-supported sub-clade in the genus Saccharomycopsis. Here, we describe this novel yeast as Saccharomycopsis oxydans sp. nov.

Six polymorphic yeast strains with strong antifungal activities isolated from dicot plants in an alkaline-lake desert region were subjected to taxonomic examination. The phylogenetic trees reconstructed by using neighbour-joining, maximum-likelihood and Bayesian methods from concatenated D1/D2 and ITS-5.8S-ITS2 sequences revealed phylogenetic affinity to Ustilaginaceae, but the large phylogenetic distance separating the isolates from the most closely related groups of species indicates that they represent a separate species. The sequences of the genes coding for the LSU rDNA, act1, rpb2 and a protein of unknown function corroborate this position. The isolates can easily be distinguished from their closest relatives by physiological tests (utilisation of carbon and nitrogen sources). Based on these results, a new species, Mycosarcoma aegyptiacum sp. nov., is proposed to accommodate the isolates. All isolates are polymorphic. Transitions between budding-yeast and pseudohyphal morphologies which take place during colony formation result in morphologically different colony sectors and invasive growth into the medium. Neither sexual mating nor sporulation was observed in cultures growing on laboratory media.

Two strains (YSP-384 and YSP-399), representing a novel Torulaspora species, were isolated from two nipa inflorescence sap samples collected in Trang province in the southern part of Thailand. The two strains had identical sequences of the D1/D2 domains of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) regions. The two strains were closest to Torulaspora maleeae CBS 10694T, but with 1.1 % nucleotide substitutions in the D1/D2 domains of the LSU rRNA gene and 5.2 % nucleotide substitutions in the ITS regions. Phylogenetic analysis based on the concatenated sequences of the ITS regions and the D1/D2 domains of the LSU rRNA gene supported that the two strains represented a distinct species in the genus Torulaspora. Some phenotypic characteristics of the two strains differed from T. maleeae including the two strains have ability to assimilate d-xylose, d-glucono-δ-lactone and melizitose, and inability to ferment maltose and raffinose, whereas T. maleeae has opposite results. Therefore, the two strains are described as representing a novel species, for which the name Torulaspora nypae sp. nov. was proposed.

Two yeast strains isolated from soil collected in Hokkaido, Japan, were found to secrete two extracellular lipases that exhibited activities at both 25 and 4 °C. Both strains could utilize olive oil, rapeseed oil, lard and fish oil as sole carbon sources. The similarity of the D1/D2 domain of the large subunit ribosomal RNA (LSU rRNA) sequence of these yeast strains to that of other yeasts in the GenBank database was very low (<96 %). The phylogenetic trees based on the LSU rRNA sequences and translation elongation factor-1-α (tef1-α) sequences indicated that both strains represented a member of the Wickerhamomyces /Candida clade. Sexual reproduction was not observed. The name Wickerhamomyces psychrolipolyticus f.a., sp. nov is proposed for this newly described yeast species producing cold-active lipases. This novel species is distinguishable from the type strains of other related species, Wickerhamomyces alni, Candida ulmi and Candida quercuum due to their abilities to grow at 4 to 30 °C, to produce lipase that is active also at 4 °C and to assimilate soluble starch.

During a survey of endophytic fungi in plant roots in secondary forests in Yunnan, China, a novel ascomyceteous taxon, Beltrania sinensis, was isolated from Quercus cocciferoides Hand.-Mazz. and Fraxinus malacophylla Hemsl. This novel species is characterized by having oval or obovoid conidiogenous cells with several apical, flat-tipped denticles, and biconic, aseptate, smooth, pale brown conidia with a hyaline to subhyaline equatorial transverse band and apical tubular appendage. Phylogenetic analysis of the combined sequences of the internal transcribed spacer and the LSU rRNA gene confirmed its novel species status within the genus Beltrania. Here, the novel species is described and illustrated, and a taxonomic key to species in the genus Beltrania is provided.

Fourteen novel lipomycetaceous yeasts species were isolated from soil samples collected from the Hokkaido, Chiba and Okinawa prefectures of Japan. Phylogenetic analyses of the D1/D2 domains of the large subunit rRNAs and translation elongation factor 1 alpha genes (TEF1-α) revealed that five strains of two species from the soil in Furano-shi, Hokkaido were related to Dipodascopsis anomala and 29 strains representing 12 species from soils in Kamogawa-shi, Chiba and Iriomote Island, Okinawa were in the Myxozyma clade. The two species of Dipodascopsis form globose or ellipsoid ascospores in their sac-like ascus and pseudohyphae. Furthermore, these species produce ascospores in their pseudohyphae and do not produce an acicular ascus, which is common among the three species including D. anomala. Therefore, we propose transferring D. anomala to the genus Babjevia and amending Babjevia. Two novel species were described and included in the genus Babjevia: Babjevia hyphoforaminiformans sp. nov. (holotype NBRC 111233; MycoBank no. MB 829051) and Babjevia hyphasca sp. nov. (holotype NBRC 112965; MycoBank no. MB 829053). The 12 species in the Myxozyma clade produce neither ascospores nor pseudohyphae and have different characteristics in assimilating several carbon sources from each other. Thus, we propose that the novel species of Lipomyces be classified as forma asexualis (f.a.). From Kamogawa-shi, Chiba (19 strains representing five species): Lipomyces melibiosiraffinosiphilus f.a., sp. nov. (holotype NBRC 111411; MycoBank no. MB 829034), Lipomyces kiyosumicus f.a., sp. nov. (holotype NBRC 111424; MycoBank no. MB 829035), Lipomyces chibensis f.a., sp. nov. (holotype NBRC 111413; MycoBank no. MB 829036), Lipomyces kamogawensis f.a., sp. nov. (holotype NBRC 112967; MycoBank no. MB 829037), Lipomyces amatsuensis f.a., sp. nov. (holotype NBRC 111420; MycoBank no. MB 829041). From Iriomote island, Okinawa (10 strains representing seven species): Lipomyces taketomicus f.a., sp. nov. (holotype NBRC 112966; MycoBank no. MB 829042), Lipomyces yaeyamensis f.a., sp. nov. (holotype NBRC 110433; MycoBank no. MB 829050), Lipomyces iriomotensis f.a., sp. nov. (holotype NBRC 110436; MycoBank no. MB 829045), Lipomyces haiminakanus f.a., sp. nov. (holotype NBRC 110435; MycoBank no. MB 829046), Lipomyces komiensis f.a., sp. nov. (holotype NBRC 110440; MycoBank no. MB 829047), Lipomyces nakamensis f.a., sp. nov. (holotype NBRC 110434; MycoBank no. MB 829048), Lipomyces sakishimensis f.a., sp. nov. (holotype NBRC 110439; MycoBank no. MB 829049).

Two Gram-positive, rod-shaped, motile, endospore-forming strains, SYSU K30003T and SYSU K30004T, were isolated from cave soil sampled in Xingyi County, Guizhou Province, south-west PR China. The 16S rRNA gene sequence results indicated that strains SYSU K30003T and SYSU K30004T had highest sequence similarities to Paenibacillus thermoaerophilus DSM 26310T (93.2 %) and Paenibacillus haemerocallicola KCTC 33185T (97.8 %), respectively. Optimum growth for both strains occurred at pH 7.0 and 37 °C. Both strains contained meso-2,6-diaminopimelic acid in their cell-wall peptidoglycan and MK-7 was the only isoprenoid quinone detected. The polar lipid profile of strain SYSU K30004T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two aminophospholipids, an unidentified glycolipid, unidentified phospholipids and two unidentified polar lipids. The polar lipid profile of strain SYSU K30003T contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unidentified glycolipid. The major fatty acids (>5 %) of strain SYSU K30003T were anteiso-C15:0, C16 : 0, anteiso-C17 : 0 and iso-C16 : 0, while those of strain SYSU K30004T were anteiso-C15:0, C16:0, anteiso-C17 : 0, iso-C15 : 0, iso-C16:0 and iso-C17 : 0. The genome G+C contents of strains SYSU K30003T and SYSU K30004T were 59.0 and 53.6 mol%, respectively. The average nucleotide identity values between strains SYSU K30003T and SYSU K30004T and other closely related Paenibacillus members were below the cut-off level (95–96 %) for species identification. Based on the results of phenotypic, chemotaxonomic and genome analyses, strains SYSU K30003T and SYSU K30004T represent two novel species of the genus Paenibacillus , for which the names Paenibacillus antri sp. nov. and Paenibacillus mesophilus sp. nov. are proposed. The type strains are SYSU K30003T (=KCTC 33956T=CGMCC 1.13505T) and SYSU K30004T (=KCTC 33957T=CGMCC 1.13872T).

A bacterial strain, designated Sp-1T, was isolated from the heterotrich ciliate Spirostomum yagiui collected from a reservoir located in Ulsan, Republic of Korea. Cells of Sp-1T were Gram stain-negative, rod-shaped, non-spore-forming, non-motile and contained poly-β-hydroxybutyrate granules. Phylogenetic analyses based on 16S rRNA gene sequences indicated that Sp-1T constituted a distinct phylogenetic lineage within different families in the order Rhizobiales with a pairwise sequence similarity of 95 % to the species of the genus Ochrobactrum: Ochrobactrum anthropi ATCC 49188T and Ochrobactrum cytisi ESC1T (family Brucellaceae ). The major cellular fatty acids were C19 : 0 cyclo ω8c (44.4 %) and C16 : 0 (32.1 %). The identified sole isoprenoid quinone was ubiquinone-10 (Q-10). The major polar lipids produced were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid, two unidentified phospholipids and three unidentified lipids. The genome size was about 5.4 Mbp and the DNA G+C content was 68.2 mol%. Sp-1T exhibited the highest average nucleotide identity value of 76.6 % and in silico DNA–DNA hybridization value of 22.1 % with Pseudoxanthobacter soli DSM 19599T (family Xanthobacteraeae). This strain is distinguishable from closely related members of the order Rhizobiales by its differential phenotypic, chemotaxonomic, genomic and phylogenetic characteristics. On the basis of evidence from polyphasic taxonomic analysis, we concluded that Sp-1T represents a novel species in a novel genus within the order Rhizobiales , for which the name Segnochrobactrum spirostomi gen. nov., sp. nov. is proposed. The type strain is Sp-1T (=KCTC 62036T=JCM 32162T). We also describe a novel family, Segnochrobactraceae fam. nov., to encompass the proposed novel genus and species.

Strains of Lysobacter , thought to play vital roles in the environment for their high enzyme production capacity, are ubiquitous in various ecosystems. During an analysis of bacterial diversity in saline soil, a Gram-stain-negative, aerobic, chitin-degrading bacterial strain, designated SJ-36T, was isolated from saline-alkaline soil sampled at Tumd Right Banner, Inner Mongolia, PR China. Strain SJ-36T grew at 4–40 °C (optimum, 30 °C), pH 5.0–10.0 (optimum, pH 7.0–8.0) and 0–6 % NaCl (optimum, 1.0 %). Oxidase and catalase activities were positive. A phylogenetic tree based on 16S rRNA gene sequences and the phylogenomic tree both showed that strain SJ-36T formed a tight clade with Lysobacter maris KMU-14T (sharing 97.6 % 16S rRNA gene similarity) and Lysobacter aestuarii S2-CT (97.8 %). The major polar lipids of strain SJ-36T were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, two unidentified lipids and one unidentified phospholipid. The major fatty acids were iso-C15 : 0 (37.5 %), summed feature 9 (14.0 %; iso-C17 : 1ω9c and/or C16 : 0 10-methyl) and iso-C11 : 0 (10.6 %). Q-8 was the predominant ubiquinone. Its genomic DNA G+C content was 66.6 mol%. The average nucleotide identity values of strain SJ-36T to L. maris KMU-14T, L. aestuarii S2-CT and other type strains were 81.5, 79.1 and <79.0 %, respectively. The results of physiological, phenotypic and phylogenetic characterizations allowed the discrimination of strain SJ-36T from its phylogenetic relatives. Lysobacter alkalisoli sp. nov. is therefore proposed with strain SJ-36T (=CGMCC 1.16756T=KCTC 43039T) as the type strain.