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Streptomyces thermoautotrophicus UBT1 T has been suggested to merit generic status due to its phylogenetic placement and distinctive phenotypes among Actinomycetia. To evaluate whether 'S. thermoautotrophicus' represents a higher taxonomic rank, 'S. thermoautotrophicus' strains UBT1 T and H1 were compared to Actinomycetia using 16S rRNA gene sequences and comparative genome analyses. The UBT1 T and H1 genomes each contain at least two different 16S rRNA sequences, which are closely related to those of Acidothermus cellulolyticus (order Acidothermales). In multigene-based phylogenomic trees, UBT1 T and H1 typically formed a sister group to the Streptosporangiales-Acidothermales clade. The Average Amino Acid Identity, Percentage of Conserved Proteins, and whole-genome Average Nucleotide Identity (Alignment Fraction) values were ≤58.5%, ≤48%, ≤75.5% (0.3) between 'S. thermoautotrophicus' and Streptosporangiales members, all below the respective thresholds for delineating genera. The values for genomics comparisons between strains UBT1 T and H1 with Acidothermales, as well as members of the genus Streptomyces, were even lower. A review of the 'S. thermoautotrophicus' proteomic profiles and KEGG orthology demonstrated that UBT1 T and H1 present pronounced differences, both tested and predicted, in phenotypic and chemotaxonomic characteristics compared to its sister clades and Streptomyces. The distinct phylogenetic position and the combination of genotypic and phenotypic characteristics justify the proposal of Carbonactinospora gen. nov., with the type species Carbonactinospora thermoautotrophica comb. nov. (type strain UBT1 T , = DSM 100163 T  = KCTC 49540 T ) belonging to Carbonactinosporaceae fam. nov. within Actinomycetia., (Copyright © 2021 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

In this study, bacterial strains Ha5 T , Ta1, and Jb2 were isolated from different colonies of weaver ant Oecophylla smaragdina. They were identified as bacterial symbionts of the ant belonging to family Acetobacteraceae and were distinguished as different strains based on distinctive random-amplified polymorphic DNA (RAPD) fingerprints. Cells of these bacterial strains were Gram-negative, rod-shaped, aerobic, non-motile, catalase-positive and oxidase-negative. They were able to grow at 15-37°C (optimum, 28-30°C) and in the presence of 0-1.5% (w/v) NaCl (optimum 0%). Their predominant cellular fatty acids were C 18:1 ω7c, C 16:0 , C 19:0 ω8c cyclo, C 14:0 , and C 16:0 2-OH. Strains Ha5 T , Ta1, and Jb2 shared highest 16S rRNA gene sequence similarity (94.56-94.63%) with Neokomagataea tanensis NBRC106556 T of family Acetobacteraceae. Both 16S rRNA gene sequence-based phylogenetic analysis and core gene-based phylogenomic analysis placed them in a distinct lineage in family Acetobacteraceae. These bacterial strains shared higher than species level thresholds in multiple overall genome-relatedness indices which indicated that they belonged to the same species. In addition, they did not belong to any of the current taxa of Acetobacteraceae as they had low pairwise average nucleotide identity (< 71%), in silico DNA-DNA hybridization (< 38%) and average amino acid identity (< 67%) values with all the type members of the family. Based on these results, bacterial strains Ha5 T , Ta1, and Jb2 represent a novel species of a novel genus in family Acetobacteaceae, for which we propose the name Oecophyllibacter saccharovorans gen. nov. sp. nov., and strain Ha5 T as the type strain.

Phylogenetic analysis based on 16S rRNA gene sequences of the genus Streptomyces showed the presence of six distinguishable clusters, with 100 % sequence similarity values among strains in each cluster; thus they shared almost the same evolutionary distance. This result corroborated well with the outcome of core gene (orthologous gene clusters) based genome phylogeny analysis of 190 genomes including the Streptomyces species in those six clusters. These preeminent results led to an investigation of genome-based indices such as digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI) and average amino acid identity (AAI) for the strains in those six clusters. Certain strains recorded genomic indices well above the threshold values (70 %, 95-96 % and >95 % for dDDH, ANI and AAI, respectively) determined for species affiliation, suggesting only one type strain belongs to described species and the other(s) may need to be reduced in taxa to a later heterotypic synonym. To conclude, the results of comprehensive analyses based on phylogenetic and genomic indices suggest that the following six reclassifications are proposed: Streptomyces flavovariabilis as a later heterotypic synonym of Streptomyces variegatus ; Streptomyces griseofuscus as a later heterotypic synonym of Streptomyces murinus ; Streptomyces kasugaensis as a later heterotypic synonym of Streptomyces celluloflavus ; Streptomyces luridiscabiei as a later heterotypic synonym of Streptomyces fulvissimus ; Streptomyces pharetrae as a later heterotypic synonym of Streptomyces glaucescens ; and Streptomyces stelliscabiei as a later heterotypic synonym of Streptomyces bottropensis .

A Gram-stain-negative, aerobic, rod-shaped, leaf-associated bacterium, designated JS23 T , was isolated from surface-sterilized leaf tissue of an oil palm grown in Singapore and was investigated by polyphasic taxonomy. Phylogenetic analyses based on 16S rRNA gene sequences and 180 conserved genes in the genome of several members of Burkholderiaceae revealed that strain JS23 T formed a distinct evolutionary lineage independent of other taxa within the family Burkholderiaceae . The predominant ubiquinone was Q-8. The primary polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and an unidentified aminophospholipid. The major fatty acids were C 16 : 0 , summed feature 3 (C 16 : 1  ω 7 c /C 16 : 1  ω 6 c ) and summed feature 8 (C 18 : 1  ω 7 c /C 18 : 1  ω 6 c ). The size of the genome is 5.36 Mbp with a DNA G+C content of 66.2 mol%. Genomic relatedness measurements such as average nucleotide identity, genome-to-genome distance and digital DNA-DNA hybridization clearly distinguished strain JS23 T from the closely related genera Burkholderia , Caballeronia , Mycetohabitans , Mycoavidus , Pandoraea , Paraburkholderia , Robbsia and Trinickia . Furthermore, average amino acid identity values and the percentages of conserved proteins, 56.0-68.4 and 28.2-45.5, respectively, were well below threshold values for genus delineation and supported the assignment of JS23 T to a novel genus. On the basis of the phylogenetic, biochemical, chemotaxonomic and phylogenomic evidence, strain JS23 T is proposed to represent a novel species of a new genus within the family Burkholderiaceae , for which the name Chitinasiproducens palmae gen. nov., sp. nov., is proposed with the type strain of JS23 T (= DSM 27307 T =KACC 17592 T ).

Pandoraea species have been isolated from diverse environmental samples and are emerging important respiratory pathogens, particularly in people with cystic fibrosis (CF). In the present study, two bacterial isolates initially recovered from consecutive sputum samples collected from a CF patient and identified as Pandoraea pnomenusa underwent a polyphasic taxonomic analysis. The isolates were found to be Gram-negative, facultative anaerobic motile bacilli and subsequently designated as strains 6399 T (=LMG29626 T =DSM103228 T ) and 7641 (=LMG29627=DSM103229), respectively. Phylogenetic analysis based on 16S rRNA and gyrB gene sequences revealed that 6399 T and 7641 formed a distinct phylogenetic lineage within the genus Pandoraea. Genome sequence comparison analysis indicated that strains 6399 T and 7641 are clonal and share 100 % similarity, however, similarity to other type strains (ANIb 73.2-88.8 %, ANIm 83.5-89.9 % and OrthoANI 83.2-89.3 %) indicates that 6399 T and 7641 do not belong to any of the reported type species. The major cellular fatty acids of 6399 T were C16 : 0 (32.1 %) C17 : 0cyclo (18.7 %) and C18 : 1ω7c (14.5 %), while Q-8 was the only respiratory quinone detected. The major polar lipids identified were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The genomic DNA G+C content of 6399 T was 62.9 (mol%). Strain 6399 T can be differentiated from other members of Pandoraea by the absence of C19 : 0ω8c cyclo and by the presence of C17 : 0ω8c cyclo. Together our data show that the bacterial strains 6399 T and 7641 represent a novel species of the genus Pandoraea, for which the name Pandoraea fibrosis sp. nov. is proposed (type strain 6399 T ).

A taxonomic study was performed on a novel Gram-stain-positive, coccus-shaped, orange-pigmented motile bacterium, designated as strain L10.15 T . The organism was isolated from a soil sample collected in Lagoon Island (close to Adelaide Island, western Antarctic Peninsula) using a quorum-quenching enrichment medium. Growth occurred at 4-30 °C, pH 6-11 and at moderately high salinity (0-15 %, w/v, NaCl), with optimal growth at 26 °C, at pH 7-8 and with 6 % (w/v) NaCl. 16S rRNA gene sequence analysis showed that strain L10.15 T belonged to the genus Planococcus and was closely related to Planococcus halocryophilus Or1 T (99.3 % similarity), Planococcus donghaensis JH1 T (99.0 %), Planococcus antarcticus DSM 14505 T (98.3 %), Planococcus plakortidis AS/ASP6 (II) T (97.6 %), Planococcus maritimus TF-9 T (97.5 %), Planococcus salinarum ISL-6 T (97.5 %) and Planococcus kocurii NCIMB 629 T (97.5 %). However, the average nucleotide identity-MUMmer analysis showed low genomic relatedness values of 71.1-81.7 % to the type strains of these closely related species of the genus Planococcus. The principal fatty acids were anteiso-C15 : 0, C16 : 1ω7c and anteiso-C17 :  0, and the major menaquinones of strain L10.15 T were MK-5 (48 %), MK-6 (6 %) and MK-7 (44 %). Polar lipid analysis revealed the presence of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and aminophospholipid. The DNA G+C content was 39.4 mol%. The phenotypic and genotypic data indicate that strain L10.15 T represents a novel species of the genus Planococcus, for which the name Planococcus versutus sp. nov. is proposed. The type strain is L10.15 T (=DSM 101994 T =KACC 18918 T ).