Emended Description Research Articles

Pararhodobacter oceanensis sp. nov., isolated from marine intertidal sediment and emended description of the genus Pararhodobacter.

A Gram-stain-negative, rod-shaped, non-motile and facultatively anaerobic bacterium, designated AM505T, was isolated from Shuangdao Bay in Weihai, China. Cells of strain AM505T were 0.4-0.8 µm wide, 1.3-3.3 µm long, catalase-positive and oxidase-positive. Strain AM505T was tolerant to moderate salt conditions. Growth occurred at 4-40 °C (optimum, 28-33 °C), pH 6.5-9.5 (pH 7.5-8.0) and with 0.5-9.0 % NaCl (w/v; 2.0-4.0 %). A phylogenetic analysis of the 16S rRNA gene indicated that strain AM505T was a member of the genus Pararhodobacter within the family Rhodobacteraceae. The most closely related neighbour was Pararhodobacter aggregans DSM 18938T (97.6 %). The average nucleotide identity value between AM505T and P. aggregans DSM 18938T was 75.3 %. The major respiratory quinone of strain AM505T was ubiquinone-10 and the predominant cellular fatty acids (>10 %) were summed feature 8 (consisting of C18 : 1ω7c and/or C18 : 1ω6c), 11-methyl C18 : 1ω7c and C18 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified aminolipid. The genomic DNA G+C content was 63.0 mol%. Based on our polyphasic taxonomic study, strain AM505T should be a novel species in the genus Pararhodobacter, for which the name Pararhodobacteroceanensis sp. nov. is proposed. The type strain is AM505T (=KCTC 62407T=MCCC 1H00289T).

Microvirga flavescens sp. nov., a novel bacterium isolated from forest soil and emended description of the genus Microvirga.

An aerobic, Gram-stain-negative, motile and rod-shaped bacterium, designated c27j1T, was isolated from a forest soil sample from the Chebaling National Nature Reserve in Guangdong Province, China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain c27j1T belongs to the genus Microvirga and was most closely related to Microvirga aerophila DSM 21344T (97.7 %) and Microvirga subterranea DSM 14364T (96.7 %). The average nucleotide identity and digital DNA-DNA hybridization values based on whole genome sequences of strain c27j1 T and M. aerophila DSM 21344T were 77.2 and 22.4 %, respectively. It contained ubiquinone 10 as the predominant quinone, and C19 : 0 cycloω8c and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) as the major fatty acids. The polar lipids consisted of phosphatidylglycerol, phosphatidylcholine, diphosphatidylglycerol, phosphatidylethanolamine and two unidentified glycolipids. The genomic DNA G+C content based on the whole genome sequence was 62.2 mol%. Phenotypic, chemotaxonomic, phylogenetic and genomic analyses suggested that strain c27j1T should represent a novel species of the genus Microvirga, for which the name Microvirgaflavescens sp. nov. is proposed. The type strain is c27j1T (=GDMCC 1.1356T=KCTC 62433T). The description of the genus Microvirga is also emended, including the major fatty acids, genome size and DNA G+C content.

Falsochrobactrum shanghaiense sp. nov., isolated from paddy soil and emended description of the genus Falsochrobactrum.

A non-spore-forming, motile, Gram-stain-negative, short rod-shaped strain, designated HN4T, was isolated from a paddy soil sample collected in Shanghai, China. A comparative analysis o-f 16S rRNA gene sequences showed that strain HN4T fell within the genus Falsochrobactrum, forming a clear cluster with the type strain of Falsochrobactrum ovis, with which it exhibited a 16S rRNA gene sequence similarity value of 98.2 %. Strain HN4T grew optimally at pH 7.0, 30-35 °C and in the presence of 1 % (w/v) NaCl. It was positive for oxidase activity. Chemotaxonomic analysis showed that strain HN4T contained ubiquinone-10 as the predominant respiratory quinone and possessed summed feature 8(C18 : 1ω7c and/or C18 : 1ω6c) and C19 : 0cyclo ω8c as predominant fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The DNA G+C content was 56.9 mol%. Strain HN4T exhibited a DNA-DNA relatedness level of 18±1 % with Falsochrobactrum ovis CCM 8460T. Based on the data obtained in this study, strain HN4T represents a novel species of the genus Falsochrobactrum, for which the name Falsochrobactrumshanghaiense sp. nov. is proposed. The type strain is HN4T (=JCM 32785T=CCTCC AB 2018063T).

Новые виды орхидных (Orchidaceae) во флоре Лаоса

This paper continues the publication of new data obtained during field studies in remote and poorly studied regions of Laos in 2015–2018. It provides descriptions of two new species (Bulbophyllum brachyscapum Aver. and Sunipia saccata Aver.), emended descriptions of two previously published but insufficiently known species (Cleisostoma verrucosum Aver., Oberonia vesiculifera Aver.) and reports of eight species newly recorded in the flora of Laos (Biermannia calcarata Aver., Bulbophyllum farreri (W. W. Sm.) Seidenf., Didymoplexiella trichechus (J. J. Sm.) Garay, Eria eriopsidobulbon C. S. P. Parish et Rchb. fil., Habenaria ciliolaris Kraenzl., Liparis caudata Aver. et K. S. Nguyen, Odontochilus umbrosus (Aver.) Ormerod, and Porpax ustulata (C. S. P. Parish et Rchb. fil.) Rolfe). Appropriate citations of regional literature, colour illustrations, data on types and distribution, descriptions, etymology, as well as notes on taxonomy and related species are provided for the studied species.

Sphingosinicella humi sp. nov., isolated from arsenic-contaminated farmland soil and emended description of the genus Sphingosinicella.

A Gram-stain-negative, strictly aerobic bacterium, designated strain QZX222T, was isolated from arsenic-contaminated farmland soil. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain QZX222T was clustered with Sphingosinicella vermicomposti YC7378T (97.0 %), Sphingosinicellaxenopeptidilytica 3-2W4T (96.1 %), Sphingosinicella microcystinivorans Y2T (96.0 %) and Sphingosinicella soli KSL-125T (95.9 %). Compared to strain QZX222T, Spingomonas olgophenolica JCM 12082T and Sphingobium boeckii 469T had 16S rRNA gene similarities of 96.2 and 95.9 %, respectively, but they located in other phylogenetic clusters. DNA-DNA hybridization and genomic ANI values between strain QZX222T and Sphingosinicella vermicomposti DSM 21593T (KCTC 22446T) were 34.8 and 75.0 %, respectively. The genome size of strain QZX222T was 3.0 Mb including 2982 predicted genes. The strain had a DNA G+C content of 65.9 mol%. Strain QZX222T had ubiquinone Q-10 as the major respiratory quinone and homospermidine as the major polyamine. The major fatty acids (>10 %) of strain QZX222T were C17 : 1ω6c, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C17 : 1ω8c. The polar lipids were sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and an unidentified glycolipid. Strain QZX222T could be distinguished from other Sphingosinicella strains based on the results of phylogenetic and genomic analyses, DNA-DNA hybridization, white colour colony, hydrolysis of urea, alkaline phosphatase activity, lack of phosphatidylmonomethylethanolamine, and presence of phosphatidylcholine. Therefore, strain QZX222T represents a novel species of Sphingosinicella, for which the name Sphingosinicellahumi sp. nov. is proposed. The type strain is QZX222T (=KCTC 62519T=CCTCC AB 2018030T).

Marinimicrobium alkaliphilum sp. nov., an alkaliphilic bacterium isolated from soil and emended description of the genus Marinimicrobium.

Two Gram-stain-negative, rod-shaped bacterial strains, designated SW121T and W12, were isolated from a soil sample collected from Shanxi Province, China. The two strains were strictly aerobic, catalase-positive and oxidase-positive. Both strains grew at 6-42 °C (optimum, 30 °C), at pH 5.5-11.0 (optimum, pH 9.0) and in the presence of 0-15.0 % (w/v) NaCl (optimum, 2.0-3.0 %). The predominant cellular fatty acids of strain SW121T were C16 : 0, C18 : 1ω7c and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). Strain SW121T contained ubiquinone-8 as the sole respiratory quinone. Diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol were major polar lipids. The genomic DNA G+C content of strain SW121T was 58.5 mol%. Comparative analysis of 16S rRNA gene sequences revealed that strains SW121T and W12 showed the highest similarities to Marinimicrobium koreense DSM 16974T(95.7 and 95.5 %, respectively). On the basis of phylogenetic inference and phenotypic characteristics, it is proposed that the two strains represent a novel species of the genus Marinimicrobium, for which the name Marinimicrobiumalkaliphilum sp. nov. is proposed. The type strain is SW121T (=CGMCC 1.16166T=KCTC 62651T).

Lutibaculum pontilimi sp. nov., isolated from a tidal mudflat and emended description of the genus Lutibaculum.

A novel Gram-reaction-negative bacterium, designated strain GH1-34T, was isolated from a sample of tidal mudflat collected at the seashore of Gangwha Island, Republic of Korea. Cells of the bacterium were strictly aerobic, catalase- and oxidase-positive, motile by means of a polar flagellum and rod shaped. It was found to grow at 0-5 % (w/v) NaCl, 20-45 °C and pH 6-10. The major isoprenoid quinone was Q-10. The polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, an unidentified aminolipid and an unidentified glycolipid. The predominant fatty acids were C18 : 1ω7c and C19 : 0cyclo ω8c. The G+C content of the DNA was 70.9 mol%. Comparative 16S rRNA gene sequence analysis revealed that strain GH1-34T formed a tight cluster with the type strain of Lutibaculum baratangense with 98.3 % sequence similarity; levels of the 16S rRNA gene sequence similarity between the novel strain and other representatives of the order 'Rhizobiales' were <95.0 %. DNA-DNA relatedness between the organism and L. baratangense KCTC 22669T was 33 %, Based on the results of phenotypic analysis and DNA-DNA hybridization experiments, strain GH1-34T (=KCTC 52847T=NBRC 113277T) represents a novel species of the genus Lutibaculum, for which the name Lutibaculum pontilimi sp. nov. is proposed.

Vallitalea okinawensis sp. nov., isolated from Okinawa Trough sediment and emended description of the genus Vallitalea.

A polyphasic study was conducted to characterize an obligately anaerobic bacterial strain, S15T, that was isolated from Okinawa Trough sediment. Strain S15T was Gram-stain-negative, non-motile and rod-shaped. Spores were not observed. Strain S15T grew anaerobically at 20-35 °C (optimum at 25-30 °C) and at pH range of 6.0-8.5 (optimum at 7.5). Analysis of 16S rRNA gene sequences showed that strain S15T was phylogenetically related to Vallitalea guaymasensis Ra1766G1T (94.0 %) and Vallitalea pronyensis FatNI3T (93.1 %). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and glycolipids. The predominant fatty acids of strain S15T were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0 and C16 : 0. The draft genome was 5.86 Mb with a DNA G+C content of 33.9 mol%. A total of 5285 genes were predicted and, of those, 4669 genes were annotated. The genome data supported the result that strain S15T assimilated various carbon sources. On the basis of unique phenotypic, chemotaxonomic and phylogenetic comparisons, strain S15T is proposed to represent a novel species within the genus Vallitalea, and the name Vallitaleaokinawensis sp. nov. is proposed. The type strain is S15T=CGMCC 1.5231T=KCTC 15675T.

A closer look at Batillipes dicrocercus and new records of Batillipes potiguarensis (Tardigrada: Arthrotardigrada) from the Brazilian coast with comments on intra- and interspecific variability

ABSTRACT Batillipes specimens collected in the Southwestern Atlantic Ocean, on the Brazilian Coast (Campos Basin and Potiguar Basin) with a bifurcated caudal appendage similar to B. dicrocercus Pollock, 1970 were assigned to B. potiguarensis Santos, da Rocha, Gomes Jr &amp; Fontoura, 2017. This species was described as having a roundish caudal protrusion but, as shown in this study, it exhibits intraspecific variability of the morphology of the caudal apparatus. The examination of specimens of B. dicrocercus from the type locality (Massachussetts, U.S.A.) and the analysis of the original description and two subsequent emended descriptions, one from the Gulf of Mexico (U.S.A.) and another from the Mediterranean Sea, used for comparison, revealed important differences among them concerning important taxonomic characters, suggesting that what was considered a single species should now be split into three different species. Therefore, an emended diagnosis of B. potiguarensis and comments on the geographic distribution of B. dicrocercus are provided, clarifying the taxonomic status of the two species.

Revising the taxonomy of the Acinetobacter lwoffii group: The description of Acinetobacter pseudolwoffii sp. nov. and emended description of Acinetobacter lwoffii

In 1986, Bouvet and Grimont delineated two related taxa of the genus Acinetobacter termed genospecies (GS) 8 and 9. They proposed the name Acinetobacter lwoffii for GS8, which included the supposed type strain (CIP 64.10). As the authenticity of CIP 64.10 was later questioned, this study aimed at reassessing the taxonomy of these genospecies. We investigated 52 strains of GS8 or GS9, including CIP 64.10 and the genuine type strain of A. lwoffii (NCTC 5866T). All strains were subjected to the genus-wide comparative analyses of MALDI-TOF whole-cell mass spectra, rpoB gene sequences and metabolic traits while whole-genome sequences were analysed for 16 strains. The strains were classified into two distinct groups corresponding to GS8 (n=15) and GS9 (n=37). CIP 64.10 fell within GS8 whereas NCTC 5866T belonged to GS9. Intraspecies ANIb values for the genomes of GS8 (n=6) and GS9 (n=10) were ≥96.1% and ≥95.4%, respectively, whereas the ANIb values between them were 86.8–88.6%. Based on core genome phylogeny, GS8 and GS9 formed a distinct clade within the genus, with two respective, strongly supported subclades. GS8 and GS9 were similar in physiological and catabolic properties but were separable by MALDI-TOF MS. We conclude that the name A. lwoffii pertains to GS9 and not to GS8 as originally assumed and that these groups represent two species. We propose the name Acinetobacter pseudolwoffii sp. nov. for GS8, with ANC 5044T (=CCM 8638T=CCUG 67963T=CIP 111642T) as the type strain, and provide the emended description of A. lwoffii.

Bennettella ceticola (Nelson ex Bennett) Holmes on the skin of Franciscana dolphin (Pontoporia blainvillei) of the Argentinean Sea: an emendation of the generic description

The presence of epizoic diatoms on the skin of a variety of large marine vertebrates, such as whales and dolphins, has been often reported in the scientific literature. The first observations of an algal growth over on the skin of cetaceans were probably made around 1920. Later studies showed the presence of a new species, Cocconeis ceticola, on skin samples. Morphological features of this species led to the transference of C. ceticola, together with related forms, to the new genus Bennettella Holmes.Here, we report the occurrence of a diatom film of Bennettella ceticola on the skin of the Franciscana dolphin (Pontoporia blainvillei), obtained from bycatch in fishermen’s gillnets at Samborombon Bay, Argentina, in April 2005. For comparison the holotype of B. ceticola, deposited in the Natural History Museum (London, U.K.) dated 1920 and labelled as Cocconeis ceticola was examined. Detailed analysis of the fine structure of B. ceticola shows that it mostly matches the original description. However, the external raphe ending is not bifurcated (as originally described), and has only one simple, parallel sided slit and polar fissures hidden by a triangular flange. The triangular flange is the main diagnostic feature distinguishing Bennettella from Epipellis Holmes and Cocconeis Ehrenberg, allowing us to propose an emended description of Bennettella. The taxonomic affinities of B. ceticola with related genera, such as Cocconeis and Epipellis, are discussed. The present study constitutes the first report of B. ceticola as an epizoic diatom of a cetacean species in waters of the Argentinean Sea.

An emended description of Stemphylium amaranthi with its first record for Iran mycobiota

Stemphylium amaranthi was originally described from the leaves of Amaranthus retroflexous in China based only on asexual morphological characteristics. New collections of S. amaranthi from wheat and barley plants with symptoms of black (sooty) head mould in Golestan and Qazvin Provinces, Iran, revealed abundant formation of a sexual morph. The morphological identification was confirmed by sequences obtained from ITS-rDNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genomic loci. New information on the sexual morph of S. amaranthi is provided and the species circumscription is emended. Wheat and barley are reported as new substrates for S. amaranthi, and this species is recorded for the first time in Iran.

Lentzea terrae sp. nov., isolated from soil and an emended description of Lentzea soli.

A novel actinobacterium, designated strain NEAU-LZS 42T, was isolated from soil collected from Mount Song, Henan Province, China, and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the organism should be assigned to the genus Lentzea and had the closest relationship with Lentzea soli NEAU-LZC 7T (99.1 % similarity) and Lentzea cavernae SYSU K10001T (98.2 %). The major menaquinones were identified as MK-9(H4) and MK-9(H2). The phospholipid profile was found to contain diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, glycophospholipid and three unidentified lipids. The major fatty acids were iso-C16 : 0, C16 : 1ω7c and C16 : 0. DNA-DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-LZS 42T could be clearly differentiated from L. soli NEAU-LZC 7T and L. cavernae SYSU K10001T. Therefore, it is concluded that strain NEAU-LZS 42T represents a novel species of the genus Lentzea, for which the name Lentzea terrae sp. nov. is proposed. The type stain is NEAU-LZS 42T (=CGMCC 4.7428T=DSM 105696T).

Halorubrum chaoviator Mancinelli et al. 2009 is a later, heterotypic synonym of Halorubrum ezzemoulense Kharroub et al. 2006. Emended description of Halorubrum ezzemoulense Kharroub et al. 2006.

A polyphasic comparative taxonomic study of Halorubrum ezzemoulense Kharroub et al. 2006, Halorubrum chaoviator Mancinelli et al. 2009 and eight new Halorubrum strains related to these haloarchaeal species was carried out. Multilocus sequence analysis using the five concatenated housekeeping genes atpB, EF-2, glnA, ppsA and rpoB', and phylogenetic analysis based on the 757 core protein sequences obtained from their genomes showed that Hrr. ezzemoulense DSM 17463T, Hrr. chaoviator Halo-G*T (=DSM 19316T) and the eight Halorubrum strains formed a robust cluster, clearly separated from the remaining species of the genus Halorubrum. The orthoANI value and digital DNA-DNA hybridization value, calculated by the Genome-to-Genome Distance Calculator (GGDC), showed percentages among Hrr. ezzemoulense DSM 17463T, Hrr. chaoviator DSM 19316T and the eight Halorubrum strains ranging from 99.4 to 97.9 %, and from 95.0 to 74.2 %, respectively, while these values for those strains and the type strains of the most closely related species of Halorubrum were 88.7-77.4 % and 36.1-22.3 %, respectively. Although some differences were observed, the phenotypic and polar lipid profiles were quite similar for all the strains studied. Overall, these data show that Hrr. ezzemoulense, Hrr. chaoviator and the eight new Halorubrum isolates constitute a single species. Thus, Hrr. chaoviator should be considered as a later, heterotypic synonym of Hrr. ezzemoulense. We propose an emended description of Hrr. ezzemoulense, including the features of Hrr. chaoviator and those of the eight new isolates.

Pontibacter silvestris sp. nov., isolated from the soil of a Populus euphratica forest and emended description of the genus Pontibacter.

Strain XAAS-R86T, a Gram-stain-negative, short rod-shaped, non-motile, aerobic bacterium, was isolated from a Populus euphratica forest near the city of Hotan, Xinjiang, PR China. The cells were found to be positive for catalase and oxidase activities. Growth occurred optimally at 28-30 °C, pH 7.0-7.5 and in the presence of 0.5-2.0 % NaCl (w/v). The results of phylogenetic analysis of the 16S rRNA gene indicated that XAAS-R86T represents a member of the genus Pontibacter within the family Hymenobacteraceae. Pontibacter akesuensis CCTCC AB 206086T is the most closely related species with a validly published name, based on 16S rRNA gene sequence identity (95.7 %). The DNA G+C content of the strain is 43.9 mol%. The main respiratory quinone is MK-7 and the major cellular fatty acids are summed feature 4 (iso-C17 : 1I and/or anteiso-C17 : 1B) and iso-C15 : 0 and its major polar lipids are phosphatidylethanolamine and two unidentified lipids. On the basis of the results of tests performed using a polyphasic approach, XAAS-R86T represents a novel species of the genus Pontibacter, for which the name Pontibactersilvestris sp. nov. is proposed, with the type strain XAAS-R86T (=CCTCC AB 2017165T=KCTC 62047T).

Aestuariimicrobium soli sp. nov., isolated from farmland soil, and emended description of the genus Aestuariimicrobium.

A Gram-reaction-positive, catalase-positive, non-spore-forming and short rod- or oval-shaped bacterial strain, designated D6T, was isolated from farmland soil in Xuancheng, Anhui Province, China. Growth occurred at 4-37 °C (optimum, 30 °C), at pH 6.5-8.5 (optimum, 7.0) and with 0-7 % (w/v) NaCl (optimum, 0.5 % NaCl). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain D6T was most closely related to Aestuariimicrobium kwangyangense DSM 21549T (98.47 %), followed by Tessaracoccus rhinocerotis YIM 101269T (94.46 %). Strain D6T had a cell-wall peptidoglycan based on ll-diaminopimelic acid. MK-9(H4) was the predominant menaquinone. The major fatty acids of strain D6T were anteiso-C15 : 0, iso-C15 : 0 and summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B). The major polar lipids were a lipid, glycolipid and phospholipid. The DNA G+C content was 69.2 mol% and strain D6T showed low DNA-DNA relatedness to A. kwangyangense DSM 21549T (36.45±0.42 %). Based on these genotypic and phenotypic data, strain D6T represents a novel species in the genus Aestuariimicrobium, for which the name Aestuariimicrobium soli sp. nov. is proposed. The type strain is D6T (=KCTC 39995T=DSM 105824T). An emended description of the genus Aestuariimicrobium is presented.

Genome-Based Taxonomic Classification of the Phylum Actinobacteria.

The application of phylogenetic taxonomic procedures led to improvements in the classification of bacteria assigned to the phylum Actinobacteria but even so there remains a need to further clarify relationships within a taxon that encompasses organisms of agricultural, biotechnological, clinical, and ecological importance. Classification of the morphologically diverse bacteria belonging to this large phylum based on a limited number of features has proved to be difficult, not least when taxonomic decisions rested heavily on interpretation of poorly resolved 16S rRNA gene trees. Here, draft genome sequences of a large collection of actinobacterial type strains were used to infer phylogenetic trees from genome-scale data using principles drawn from phylogenetic systematics. The majority of taxa were found to be monophyletic but several orders, families, and genera, as well as many species and a few subspecies were shown to be in need of revision leading to proposals for the recognition of 2 orders, 10 families, and 17 genera, as well as the transfer of over 100 species to other genera. In addition, emended descriptions are given for many species mainly involving the addition of data on genome size and DNA G+C content, the former can be considered to be a valuable taxonomic marker in actinobacterial systematics. Many of the incongruities detected when the results of the present study were compared with existing classifications had been recognized from 16S rRNA gene trees though whole-genome phylogenies proved to be much better resolved. The few significant incongruities found between 16S/23S rRNA and whole genome trees underline the pitfalls inherent in phylogenies based upon single gene sequences. Similarly good congruence was found between the discontinuous distribution of phenotypic properties and taxa delineated in the phylogenetic trees though diverse non-monophyletic taxa appeared to be based on the use of plesiomorphic character states as diagnostic features.

Isolation and characterization of a novel 1-aminocyclopropane-1-carboxylate (ACC) deaminase producing plant growth promoting marine Gammaproteobacteria from crops grown in brackish environments. Proposal for Pokkaliibacter plantistimulans gen. nov., sp. nov., Balneatrichaceae fam. nov. in the order Oceanospirillales and an emended description of the genus Balneatrix

Three novel strains namely, L1E11T, L1E4 and 228 were isolated as part of an ongoing study on 1-aminocyclopropane-1-carboxylate (ACC) deaminase expressing rhizobacteria from crops cultivated in saline affected coastal agro-ecosystems of Kerala, India. The novel strains were positive for many properties that are beneficial to plant growth including ACC deaminase (ACCd) activity that ranged from 1.87±0.27 to 2.88±0.71μmol of α-ketobutyrate/hr/mg of total protein. Presence of other traits such as biofilm formation, siderophore production, phosphate solubilisation, utilisation of root derived compounds and ability to colonise host roots indicates its plant-associated life style. In complement, the genomic data reveals gene features for higher adaptation to plant-associated environments. In-planta assays showed that L1E11T can promote and protect pokkali rice plants from 200mM NaCl stress. Phylogenetic, chemotaxonomic, phenotypic and genomic characterisation indicates that the novel strains belong to a novel genus and species of the order Oceanospirillales for which the names Pokkaliibacter gen. nov., and Pokkaliibacter plantistimulans sp. nov., are proposed with L1E11T (=DSM 28732T=MCC 2992T) as the type strain. Further, on the basis of low 16S rRNA sequence similarity, phylogenetic divergence, source of isolation and few differences in the phenotypic properties against its nearest taxon, a new family Balneatrichaceae fam. nov., is proposed to accommodate the two genera Balneatrix and Pokkaliibacter gen.nov. with Balneatrix as the type genus. An emended description of the genus Balneatrix is also presented.

Solitalea longa sp. nov., isolated from freshwater and emended description of the genus Solitalea.

A Gram-negative, strictly aerobic, oxidase-positive, catalase-negative and yellow-pigmented bacterium, designated strain HR-AVT, was isolated from a water sample of the Han River. Cells were elongated rods with gliding motility without flagellum. Growth was observed at 5-30 °C (optimum, 20 °C), pH 7-8 and 0-0.5 % NaCl. The major respiratory quinone was menaquinone-7. The major fatty acids were iso-C15 : 0, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c) and anteiso-C15 : 0. The polar lipids comprised phosphatidylethanolamine, an unidentified amino lipid and five unidentified lipids. The DNA G+C content of strain HR-AVT was 38.4 mol%. Results of phylogenetic analysis based on 16S rRNA gene sequences revealed that strain HR-AVTbelonged to the family Sphingobacteriaceae in the phylum Bacteroidetes and formed a phylogenic lineage with Solitalea canadensis DSM 3403T and Solitalea koreensis R2A36-4T. Strain HR-AVT was most closely related to S. canadensis DSM 3403T and S. koreensis R2A36-4T with 97.3 and 94.0 % 16S rRNA gene sequence similarities, respectively, and then had low similarities (below 90.9 %) with other bacteria with validly published names. Average nucleotide identity and in silico DNA-DNA hybridization values between strain HR-AVT and S. canadensis were 74.0 and 19.7 %, respectively. Based on these results, strain HR-AVT represents a novel species of the genus Solitalea, for which the name Solitalea longa sp. nov. is proposed. The type strain is HR-AVT (=KACC 19411T=JCM 32259T). An emended description of the genus Solitalea is also proposed.

An emended description of Neofusicoccum brasiliense and characterization of Neoscytalidium and Pseudofusicoccum species associated with tropical fruit plants in northeastern Brazil

The Botryosphaeriaceae family is one of the most important groups of plant pathogenic fungi associated with tropical woody species such as Anacardium occidentale (cashew) and Mangifera indica (mango), which are fruiting species with broad distributions and high economic importance in north-eastern Brazil. This study was designed to characterize species of this family associated with cashew, mango and Psidium guajava (guava) that cause dieback and stem and branch cankers. Characterization comprised phylogenetic, morphological, physiological and pathogenic features. The phylogenetic study combined sequences of the internal transcribed spacer (ITS) of the rDNA and partial elongation factor 1-α (EF1-α) regions of DNA. Measurements of fungal conidia and colony growth on different culture media and at different temperatures were conducted. Pathogenicity tests were also performed through inoculation of different host species. By combining the sequences of the referenced genes, it was possible to identify the following Botryosphaeriaceae species: Neofusicoccum kwambonambiense, Neoscytalidium hyalinum and Pseudofusicoccum stromaticum as the first report in cashew, Neoscytalidium hyalinum in mango and Neofusicoccum brasiliense as the first report in guava. Examination of N. brasiliense revealed conidia, providing the first morphological description of the species. Neofusicoccum kwambonambiense did not sporulate, but the other isolates produced conidia with dimensions comparable to those described in the literature. All isolates were virulent to mango fruits and young cashew and “caja-umbu” plants, causing necrotic lesions and gum exudation by the hosts. The isolates of Neofusicoccum were the most aggressive in the inoculated hosts.