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In radiation-resistant bacteria belonging to the genus Deinococcus, transposition events of insertion sequences (IS elements) leading to phenotypic changes from a reddish color to white were detected following exposure to gamma irradiation and hydrogen peroxide treatment. This change resulted from the integration of IS elements into the phytoene desaturase gene, a key enzyme in the carotenoid biosynthesis pathway. To facilitate species identification and distinguish among Deinococcus strains, the gyrB gene encoding the B subunit of DNA gyrase was utilized. The s gnificance of the gyrB gene is well recognized not only in genome replication through the regulation of supercoiling but also in phylogenetic analysis providing support for 16S rRNA-based identification. Its mutation rate surpasses that of the 16S rRNA gene, offering greater resolution between closely related species, particularly those exhibiting >99% similarity. In this study, phylogenetic analysis was conducted comparing the 16S rRNA and gyrB gene sequences of Deinococcus species. Species-specific and genus-specific primers targeting Deinococcus species were designed and experimentally validated for selective amplification and rapid identification of the targeted species. This approach allows for the omission of 16S rRNA sequencing in the targeted Deinococcus species. Therefore, the gyrB gene is useful for identifying bacterial species and genus-level detection from individual microbes or microbial consortia using specialized primer sets for PCR amplification., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

A Gram-stain-positive, aerobic, non-mobile and spherical strain, designated ZS9-10 T , belonging to the genus Deinococcus was isolated from soil sampled at the Chinese Zhong Shan Station, Antarctica. Growth was observed in the presence of 0-4 % (w/v) NaCl, at pH 7.0-8.0 and at 4-25 °C. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain ZS9-10 T formed a lineage in the genus Deinococcus . It exhibited highest sequence similarity (97.4 %) to Deinococcus marmoris DSM 12784 T . The major phospholipids of ZS9-10 T were unidentified phosphoglycolipid, unidentified glycolipids and unidentified lipids. The major fatty acids were summed feature 3 (C 16 : 1  ω 7 c and/or C 16 : 1  ω 6 c ), C 16 : 0 and C 16 : 1  ω 7 c . MK-8 was the predominant respiratory quinone. The digital DNA-DNA hybridization and average nucleotide identity values between strain ZS9-10 T and its close relative D. marmoris DSM 12784 T were 27.4 and 83.9 %, respectively. Based on phenotypic, phylogenetic and genotypic data, a novel species, named Deinococcus arenicola sp. nov., is proposed. The type strain iis ZS9-10 T (=CCTCC AB 2019392 T =KCTC43192 T ).

Deinococcus radiodurans is a phylogenetically deep-branching extremophilic bacterium that is remarkably tolerant to numerous environmental stresses, including large doses of ultraviolet (UV) radiation and extreme temperatures. It can even survive in outer space for several years. This endurance of D. radiodurans has been partly ascribed to its atypical cell envelope comprising an inner membrane, a large periplasmic space with a thick peptidoglycan (PG) layer, and an outer membrane (OM) covered by a surface layer (S-layer). Despite intense research, molecular principles governing envelope organization and OM stabilization are unclear in D. radiodurans and related bacteria. Here, we report a electron cryomicroscopy (cryo-EM) structure of the abundant D. radiodurans OM protein SlpA, showing how its C-terminal segment forms homotrimers of 30-stranded β-barrels in the OM, whereas its N-terminal segment forms long, homotrimeric coiled coils linking the OM to the PG layer via S-layer homology (SLH) domains. Furthermore, using protein structure prediction and sequence-based bioinformatic analysis, we show that SlpA-like putative OM-PG connector proteins are widespread in phylogenetically deep-branching Gram-negative bacteria. Finally, combining our atomic structures with fluorescence and electron microscopy of cell envelopes of wild-type and mutant bacterial strains, we report a model for the cell surface of D. radiodurans . Our results will have important implications for understanding the cell surface organization and hyperstability of D. radiodurans and related bacteria and the evolutionary transition between Gram-negative and Gram-positive bacteria.

Deinococcus species are widely studied due to their utility in bioremediation of sites contaminated with radioactive elements. In the present study, we re-evaluated the taxonomic placement of two species of the genus Deinococcus namely D. swuensis DY59 T and D. radiopugnans ATCC 19172 T based on whole genome analyses. The 16S rRNA gene analysis revealed a 99.58% sequence similarity between this species pair that is above the recommended threshold value for species delineation. These two species also clustered together in both the 16S rRNA gene and core genome based phylogenies depicting their close relatedness. Furthermore, more than 98% of genes were shared between D. swuensi s DY59 T and D. radiopugnans ATCC 19172 T . Interestingly, D. swuensis DY59 T and D. radiopugnans ATCC 19172 T shared high genome similarity in different genomic indices. They displayed an average nucleotide identity value of 97.63%, an average amino acid identity value of 97% and a digital DNA-DNA hybridization value equal to 79.50%, all of which are well above the cut-off for species delineation. Altogether, based on these evidences, D. swuensis DY59 T and D. radiopugnans ATCC 19172 T constitute a single species. Hence, as per the priority of publication, we propose that Deinococcus swuensis Lee et al. 2015 should be reclassified as a later heterotypic synonym of Deinococcus radiopugnans .

There is an expectation that analyses of molecular sequences might be able to distinguish between alternative hypotheses for ancient relationships, but the phylogenetic methods used and types of data analyzed are of critical importance in any attempt to recover historical signal. Here, we discuss some common issues that can influence the topology of trees obtained when using overly simple models to analyze molecular data that often display complicated patterns of sequence heterogeneity. To illustrate our discussion, we have used three examples of inferred relationships which have changed radically as models and methods of analysis have improved. In two of these examples, the sister-group relationship between thermophilic Thermus and mesophilic Deinococcus, and the position of long-branch Microsporidia among eukaryotes, we show that recovering what is now generally considered to be the correct tree is critically dependent on the fit between model and data. In the third example, the position of eukaryotes in the tree of life, the hypothesis that is currently supported by the best available methods is fundamentally different from the classical view of relationships between major cellular domains. Since heterogeneity appears to be pervasive and varied among all molecular sequence data, and even the best available models can still struggle to deal with some problems, the issues we discuss are generally relevant to phylogenetic analyses. It remains essential to maintain a critical attitude to all trees as hypotheses of relationship that may change with more data and better methods., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)

A Gram-staining-positive, non-motile, coccus or short-rod-shaped bacterium, designated H1 T , was isolated from a humus soil sample in the Detaille Island of Antarctica. The 16S rRNA gene sequence result indicated that strain H1 T shared the highest 16S rRNA gene sequence identity with the type strain of Deinococcus alpinitundrae (96.2%). Growth of strain H1 T occurred at 4-25 °C, pH 6.0-8.0 and in the presence of 0-1.0% NaCl (w/v). The respiratory quinone was MK-8. The major fatty acids were C 16:0 , C 17:0 cyclo and summed feature 3 (C 16:1 ω7c/C 16:1 ω6c). The polar lipids were aminoglycophospholipid, aminophospholipid, glycolipid and glycophospholipid. The cell wall peptidoglycan type was A3β. The genomic DNA G + C content was 61.3 mol%. The average nucleotide identity (ANI) between strain H1 T and the closely related Deinococcus members was below the cut-off level (95-96%) for species identification. Based on the above results, strain H1 T represents a novel species of the genus Deinococcus, for which the name Deinococcus detaillensis sp. nov. is proposed. Type strain is H1 T (= CGMCC 1.13938 T  = JCM 33291 T ).

An aerobic, oligotrophic, Gram-positive, non-sporulating, motile, rod-shaped, palladium-leaching bacterial strain, Deinococcus sp. KR-1, was previously isolated from pond water collected in Japan. This strain grew at 10 °C to 40 °C (optimum 30 °C), at pH 4.5 to 11.5 (optimum pH 8.0), and in the presence of 2.0% NaCl. Its major cellular fatty acids were C 15: 1 ω6 and C 16 : 1 ω7c. The quinone system was menaquinone 8. Multilocus sequence analysis based on partial sequences of four housekeeping genes (atpD, dnaA, gyrB and rpoB) showed that branching of Deinococcus sp. KR-1 was distant to those of Deinococcus type strains. The genome average nucleotide identity value between strain KR-1 and its closest related Deinococcus type strain was less than 95.69%. Based on its phenotypic, chemotaxonomic and phylogenetic data, strain KR-1 (= HUT-8138 T  = KCTC 33977 T ) can be considered a novel species within the genus Deinococcus with the proposed name Deinococcus kurensis sp. nov.

Strain SDU3-2 T was isolated from a soil sample collected in Shandong Province, PR China. Cells of SDU3-2 T were spherical, Gram-stain-positive, aerobic and non-motile. Cellular growth of the strain occurred at 25-45 °C, pH 5.5-8.5 and with 0-1.5 % (w/v) of NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain SDU3-2 T was closest to the type strain Deinococcus murrayi ALT-1b T with a similarity of 95.2 %. The draft genome was 3.49 Mbp long with 69.2 mol% G+C content. Strain SDU3-2 T exhibited high resistance to gamma radiation (D 10 >12 kGy) and UV (D 10 >900 J m -2 ). The strain encoded many genes for resistance to radiation and oxidative stress, which were highly conserved with other Deinococcus species, but possessed interspecific properties. The major fatty acids of SDU3-2 T cells were C 15 : 1  ω 6 c , C 16 : 1  ω 7 c /C 16 : 1  ω 6 c , and C 17 : 1  ω 8 c , the major menaquinone was menaquinone-8, and the major polar lipids were an unidentified phosphoglycolipid, four unidentified glycolipids and an unidentified phospholipid. The average nucleotide identity and DNA-DNA hybridization results further indicated that strain SDU3-2 T represents a new species in the genus Deinococcus , for which the name Deinococcus terrestris sp. nov. is proposed. The type strain is SDU3-2 T (=CGMCC 1.17147 T =KCTC 43098 T ).

A Gram-stain-negative, non-motile, strictly aerobic, coccus-shaped bacterium, designated S14-83 T , was isolated from a soil sample collected from the South Shetland Islands of Antarctica. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain is a novel member of the genus Deinococcus , with Deinococcus alpinitundrae as its closest relative (96.1 % similarity). The DNA G+C content of the strain was 61.1 mol% and the major respiratory quinone was MK-8. Major cellular fatty acids were summed feature 3 (C 16 : 1 ω7 c /C 16 : 1 ω6 c ) and C 16 : 0 . As well as containing glycophospholipid, aminophospholipids and glycolipid as major polar lipids, there were also some unknown polar lipids. The diagnostic diamino acid in the cell-wall peptidoglycan was ornithine, corroborating the assignment of the strain to the genus Deinococcus . Strain S14-83 T was shown to be extremely resistant to gamma radiation (>10 kGy) and UV light (460 Jm -2 ). On the basis of phylogenetic, chemotaxonomic and phenotypic data presented here, strain S14-83 T represents a novel species of the genus Deinococcus , for which the name Deinococcus psychrotolerans sp. nov. is proposed. The type strain is S14-83 T (=CCTCC AB 2015449 T = DSM 105285 T ).

A Gram-stain-negative, non-motile, aerobic, short rod-shaped bacterium, designated OD32 T , was isolated from a soil sample taken from the rhizosphere of Silene acaulis collected from the Arctic tundra. The novel strain, OD32 T , was able to grow at 15-37 °C (optimum, 33 °C), pH 6.5-9.5 (pH 7.5-8.0) and 0-0.5 % NaCl (0 %, w/v). A phylogenetic analysis based on 16S rRNA gene sequences revealed that strain OD32 T was most closely related to the genus Deinococcus ; it shared the highest sequence similarity (95.7 %) with Deinococcus grandis ATCC 43672 T . Genomic DNA G+C content of the strain OD32 T was 68.2 mol%. The predominant respiratory quinone was menaquinone 8 (MK-8). The major fatty acids were summed feature 3 (C 16 : 1 ω 7 c /C 16 : 1 ω 6 c ), C 15 : 1 ω 6 c , C 17 : 1 ω 6 c , C 17 : 0 , C 16 : 0 and iso-C 17 : 0 . Based on phylogenetic inference and genotypic characteristics, strain OD32 T represents a novel species of the genus Deinococcus , for which the name Deinococcus arcticus sp. nov. is proposed. The type strain is OD32 T (=KCTC 33972 T =CICC 24671 T ).

A Gram-stain-negative, aerobic, non-motile and coccus-shaped bacterium, designated strain FeSDHB5-19 T , was isolated from a biofilm sample collected from a radioactive thermal spring (Budapest, Hungary), after exposure to 5 kGy gamma radiation. A polyphasic approach was used to study the taxonomic properties of strain FeSDHB5-19 T , which had highest 16S rRNA gene sequence similarity to Deinococcus antarcticus G3-6-20 T (96.5 %). The 16S rRNA gene sequence similarity to type strains of other Deinococcus species were 93.0 % or lower. The DNA G+C content of the draft genome sequence, consisting of 3.9 Mb, was 63.9 mol%. Strain FeSHDB5-19 T was found to grow at temperatures of 10-32 °C (optimum, 28 °C) and pH 5-10 (pH 6.5-7.5) and tolerated up to 1.5 % NaCl (w/v) with optimum growth at 0-0.5 % NaCl. The predominant fatty acids (>10 %) were C16 : 0 and C16 : 1ω7c. The cell-wall peptidoglycan type was A3β l-Orn-Gly1-2. The whole-cell sugars were glucose and low amounts of galactose. Strain FeSDHB5-19 T possessed MK-8 as the predominant respiratory quinone, typical of the genus Deinococcus. The polar lipid profile contained unidentified phosphoglycolipids and unidentified glycolipids. The isolate was found to be highly resistant to gamma (D10<8 kGy) and UV (D10~800 J m -2 ) radiation. According to its genotypic, phenotypic and chemotaxonomic characteristics, strain FeSDHB5-19 T represents a novel species in the genus Deinococcus, for which the name Deinococcusfonticola sp. nov. is proposed. The type strain is FeSDHB5-19 T (=NCAIM B.02639 T =DSM 106917 T ).

A bacterial strain, S13-1-2-1 T , was isolated from a soil sample collected in Gyeongsangnam-do province, South Korea. Cells were observed to be Gram-stain negative, short rod-shaped and colonies to be pale pink in colour. Analysis of 16S rRNA gene sequences identified this strain as a member of the genus Deinococcus in the family Deinococcaceae, with high levels of sequence similarity with Deinococcus ficus CC-FR2-10 T (97.9%) and Deinococcus enclensis NIO-1023 T (95.4%). Growth of strain S13-1-2-1 T was observed at 10-42 °C, pH 6-8, and in the presence of 0-1.0% NaCl. The isolate was found to exhibit resistance to gamma radiation (D 10 10.1 KGy) and UV-light (D 10 612 J/m 2 ). The major peptidoglycan amino acids were identified as D-glutamic acid, glycine, alanine and L-ornithine. The predominant respiratory quinone of the strain was identified as menaquinone-8, the major fatty acids were found to be C 16:1 ω7c (31.4%), C 16:0 (18.4%), and C 17:1 ω8c (17.4%) and the major polar lipids were observed to be an unidentified phosphoglycolipid and an unidentified glycolipid. The genomic DNA G + C content of the strain was determined to be 69.2 mol%. DNA-DNA hybridization with D. ficus showed a relatedness value of 31.5 ± 4.2%. The DNA-DNA hybridization result and the differentiating phenotypic properties clearly indicate that strain S13-1-2-1 T represents a novel species in the genus Deinococcus, for which the name Deinococcus terrigena sp. nov. is proposed. The type strain is S13-1-2-1 T (= KCTC 33939 T  = JCM 32248 T ).

Strain 17bor-2 T , a gamma-resistant, pink-to-red-coloured, aerobic, catalase-positive, oxidase-negative and Gram-stain-negative bacterium, was isolated from gamma ray-irradiated soil. The isolate grew aerobically at 18-37 °C (optimum, 28-30 °C), pH 6.0-8.0 (pH 6.5-7.5) and in the presence of 0-1 % (w/v) NaCl (0 % NaCl). Phylogenetic analysis based on its 16S rRNA gene sequence indicated that strain 17bor-2 T belonged to the genus Deinococcus with a highest sequence similarity of 96.4 % to Deinococcus alpinitundrae ME-04-04-52 T . The major fatty acids of the strain were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and cyclo C17 : 0. The only respiratory quinone was MK-8. The major polar lipids of the strain were phosphoglycolipid, aminophospholipid and an unknown glycolipid. The DNA G+C content of strain 17bor-2 T was 62.8 mol%. On the basis of its phenotypic, genotypic and chemotaxonomic characteristics, strain 17bor-2 T should be classified as a novel species in the genus Deinococcus, for which the name Deinococcusirradiatisoli sp. nov. is proposed. The type strain is 17bor-2 T (=KCTC 33907 T =NBRC 113037 T ).

A gamma radiation-resistant, Gram-stain-negative, rod-shaped bacterial strain, designated SJW1-2 T , was isolated from freshwater samples collected from the Seomjin River, Republic of Korea. The 16S rRNA gene sequence analyses showed that strain SJW1-2 T was most closely related to Deinococcus metalli 1PNM-19 T (94.3 % sequence similarity) and formed a robust phylogenetic clade with other species of the genus Deinococcus. The optimum growth pH and temperature for the isolate were pH 7.0-7.5 and 25 °C, respectively. Strain SJW1-2 T exhibited high resistance to gamma radiation. The predominant respiratory quinone was MK-8. The polar lipid profile consisted of different unidentified glycolipids, two unidentified lipids, two unidentified phospholipids and an unidentified phosphoglycolipid. The major peptidoglycan amino acids were alanine, d-glutamic acid, glycine and l-ornithine. The predominant fatty acids (>10 %) were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) (25.2 %) and C16 : 0 (21.2 %), and the DNA G+C content was 69.5 mol%. On the basis of phenotypic, genotypic and phylogenetic analyses, strain SJW1-2 T (=KACC 19332 T =NBRC 112908 T ) represents a novel species of the genus Deinococcus, for which the name Deinococcus koreensis sp. nov. is proposed.

Fruit flies are the most economically important group of phytophagous flies worldwide. Whereas the ecological role of bacteria associated with tephritid fruit fly species of the genera Bactrocera and Ceratitis has been demonstrated, the diversity of the bacterial community in Anastrepha has been poorly characterized. This study represents the first comprehensive analysis of the bacterial community in the gut of larvae and adults of Anastrepha ludens, A. obliqua, A. serpentina, and A. striata using 454 pyrosequencing. A total of four phyla, seven classes, 11 families, and 27 bacterial genera were identified. Proteobacteria was the most represented phylum, followed by Firmicutes, Actinobacteria, and Deinococcus-Thermus. The genera Citrobacter, Enterobacter, Escherichia, Klebsiella, and Raoultella were dominant in all samples analyzed. In general, the bacterial community diversity in adult flies was higher in species with a broader diet breadth than species with a restricted number of hosts, whereas it was also higher in adults versus larvae. Differences in bacterial communities in adults might be determined by the number of fruit species infested. Lastly, the predictive functional profile analysis suggested that community members may participate in metabolic pathways related to membrane transport and metabolism of carbohydrates, amino acids, cofactors, and lipids. These results provide the basis for the study of unexplored functional roles of bacteria in this insect group.

A Gram-stain-negative, non-motile, rod-shaped, red-pigmented strain, designated W37 T , was isolated from soil near an iron factory in Busan (Republic of Korea). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain W37 T was most closely related to Deinococcus yunweiensis YIM 007 T (98.3 %) and Deinococcus radioresistens 8A T (96.3 %). The DNA-DNA relatedness between strain W37 T and D. yunweiensis YIM 007 T was 50.5 %. The predominant respiratory quinone was MK-8. The major polar lipids were an unidentified phosphoglycolipid, an unidentified aminophospholipid, four unidentified glycolipids, two unidentified phospholipids and an unidentified lipid. The major fatty acids (>5 %) of strain W37 T were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0, C17 : 1ω8c and iso-C17 : 1ω9c. The DNA G+C content was 69.0 mol%. Moreover, the chemo-physical characteristics of strain W37 T clearly differed from those of related species, including ranges of growth temperature and pH, positive activity for 4-hydroxybenzoate and negative activity for cystine arylamidase. Phenotypic, chemotaxonomic and genotypic analyses indicated that strain W37 T represents a novel species of the genus Deinococcus, for which the name Deinococcus rufus sp. nov., is proposed. The type strain is W37 T (=KCTC 33913 T =CCTCC AB 2017081 T ).

A Gram-stain-negative, pink-coloured, non-motile and gamma radiation-resistant bacterium, designated strain IMCC1711 T , was isolated from a freshwater sample collected from an artificial pond (Inkyong Pond). The 16S rRNA gene sequence analysis showed that strain IMCC1711 T was most closely related to Deinococcus piscis 3ax T (94.2 %) and formed a robust phylogenetic clade with other species of the genus Deinococcus. Optimal growth of strain MCC1711 T was observed at 25 °C and pH 7.0 without NaCl. Strain IMCC1711 T exhibited high resistance to gamma radiation. The DNA G+C content of strain IMCC1711 T was 59.1 mol% and MK-8 was the predominant isoprenoid quinone. Major fatty acid constituents of the strain were C17 : 1ω8c, C16 : 0, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and C15 : 1ω6c. The major polar lipids constituted phosphatidylethanolamine, one unidentified phosphoglycolipid and two unidentified glycolipids. On the basis of taxonomic data obtained in this study, it was concluded that strain IMCC1711 T represented a novel species of the genus Deinococcus, for which the name Deinococcus lacus sp. nov. is proposed. The type strain of Deinococcus lacus is IMCC1711 T (KCTC 52494 T =KACC 18979 T =NBRC 112440 T ).

A gamma radiation-resistant and pink-to-red pigmented bacterial strain, designated ID1504 T , was isolated from a car air-conditioning system sampled in Korea. The cells were observed to be Gram-stain negative, aerobic, motile with peritrichous flagella and short rod-shaped. Phylogenetically, the strain groups with the members of the genus Deinococcus and exhibits high 16S rRNA gene sequence similarities with Deinococcus arenae SA1 T (94.0%), Deinococcus actinosclerus BM2 T (93.9%) and Deinococcus soli N5 T (93.5%). The predominant fatty acids were identified as C 17:0 , C 16:0 , summed feature 3 (C 16:1 ω7c and/or C 16:1 ω6c) and iso-C 17:0 . The major respiratory quinone was identified as MK-8. The polar lipids were found to be comprised of unidentified phospholipids, unidentified glycolipids, an unidentified aminophospholipid and an unidentified lipid. The DNA G+C content of the strain was determined to be 68.3 mol%. On the basis of the phenotypic, genotypic and chemotaxonomic characteristics, strain ID1504 T should be classified in a novel species in the genus Deinococcus, for which the name Deinococcus multiflagellatus sp. nov. (= KACC 19287 T  = NBRC 112888 T ) is proposed.

A Gram-stain positive, non-motile, spherical, red-pigmented and facultatively anaerobic bacterium, designated strain 6.1 T , was isolated from a crude oil recovery water sample from the Huabei oil field in China. The novel strain exhibited tolerance of UV irradiation (> 1000 J m -2 ). Based on 16S rRNA gene sequence comparisons, strain 6.1 T shows high similarity to Deinococcus citri DSM 24791 T (98.1%) and Deinococcus gobiensis I-0 T (97.8%), with less than 93.5% similarity to other closely related taxa. The major cellular fatty acids were identified as summed feature 3 (C 16:1 ω7c and/or iso-C 15:0 2-OH), followed by iso-C 17:1 ω9c and C 16:0 . The polar lipid profile was found to contain phospholipids, glycolipids, phosphoglycolipids and aminophospholipids. The predominant respiratory quinone was identified as MK-8. The DNA G + C content was determined to be 68.3 mol %. DNA-DNA hybridization between strain 6.1 T and D. citri DSM 24791 T was 45.6 ± 7.1% and with D. gobiensis I-O T was 36.6 ± 4.7%. On the basis of phylogenetic, chemotaxonomic and phenotypic data, we conclude strain 6.1 T represents a novel species of the genus Deinococcus, for which we propose the name Deinococcus petrolearius sp. nov. The type strain is 6.1 T (= CGMCC 1.15053 T  = KCTC 33744 T ).

A bacterial strain designated PtRA-8 T was isolated from the trunk surface of a Japanese aspen tree (Populus tremula var. sieboldii). Cells of strain PtRA-8 T were aerobic, non-motile, non-spore forming, Gram-stain-negative rods, 1.0‒2.0 µm in width and 3.0‒10.0 µm in length. The pH range for growth was between 5.5 and 7.5, with an optimum at 6.5. The temperature range for growth was between 10 and 37 °C, with an optimum at around 25‒30 °C. Strain PtRA-8 T was highly resistant to UV irradiation, similar to its Deinococcus relatives. The respiratory quinone was menaquinone MK-8. The major cellular fatty acids (> 10% of the total fatty acid content) were iso-C 15:0 (17.8%), C 16:0 (15.0%), iso-C 17:0 (10.4%), and iso-C 17:1 ω9c/C 16:0 10-methyl (22.2%). The polar lipids consisted of four unidentified glycolipids, two unidentified aminolipids, two unidentified phospholipids, and three unidentified polar lipids. The peptidoglycan was A3β-type containing glutamic acid, glycine, alanine, and ornithine. The DNA G + C content of strain PtRA-8 T was 68.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PtRA-8 T was closely related to "Deinococcus radioresistens" 8A T (97.4%), Deinococcus metalli DSM 27521 T (95.7%), and Deinococcus yunweiensis YIM 007 T (94.5%). The DNA-DNA hybridization experiments between strain PtRA-8 T and its relatives yielded relatedness values below 70%. Based on the polyphasic evidence, we concluded that strain PtRA-8 T represents a novel species within the genus Deinococcus, for which the name Deinococcus populi is proposed. The type strain of D. populi is PtRA-8 T (= DSM 29820 T = NBRC 110763 T ; DPD TaxonNumber TA00271).

A Gram-stain-positive, pink-pigmented, coccus-shaped, strictly aerobic, non-motile bacterium, strain THG-AG1.5 T , was isolated from rhizosphere of Hibiscus syriacus L. (Mugunghwa flower) located in Kyung Hee University, Yongin, Gyeonggi, Republic of Korea. The isolated strain grew optimally at 25-30 °C, at pH 6.0-7.5 and in the presence of additional 0-1.5 % (w/v) NaCl. Strain THG-AG1.5 T exhibited tolerance to UV radiation (>1500 J m -2 ) and to gamma radiation (>12 kGy). Based on 16S rRNA gene sequence comparisons, strain THG-AG1.5 T was closely related to Deinococcus daejeonensis MJ27 T (98.03 %), Deinococcus radiotolerans C1 T (97.61 %) and Deinococcus grandis DSM 3963 T (97.32 %). The genomic DNA G+C content of strain THG-AG1.5 T was 74.8 mol%. The DNA-DNA hybridization values between strain THG-AG1.5 T and its closest phylogenetically neighbours were below 63.0 %. The peptidoglycan amino acids were alanine, valine, glutamic acid, glycine, ornithine, lysine and aspartic acid. Strain THG-AG1.5 T contained ribose, mannose and glucose as whole-cell-wall sugars and menaquinone-8 (MK-8) as the only isoprenoid quinone. The major component in the polyamine pattern was spermidine. The major polar lipids of strain THG-AG1.5 T were a phosphoglycolipid, six unidentified glycolipids and an unidentified aminophospholipid. The major fatty acids were identified as iso-C15 : 0, C15 : 1ω6c, C16 : 0, iso-C17 : 0, C17 : 0, C18 : 0 and summed feature 3. On the basis of our polyphasic taxonomy study, strain THG-AG1.5 T represents a novel species within the genus Deinococcus, for which the name Deinococcushibisci sp. nov. is proposed. The type strain is THG-AG1.5 T (=KACC 18850 T =CCTCC AB 2016078 T ).

Xaa-Pro peptidases (XPP) are dinuclear peptidases of MEROPS M24B family that hydrolyze Xaa-Pro iminopeptide bond with a trans-proline at the second position of the peptide substrate. XPPs specific towards dipeptides are called prolidases while those that prefer longer oligopeptides are called aminopeptidases P. Though XPPs are strictly conserved in bacterial and archaeal species, the structural and sequence features that distinguish between prolidases and aminopeptidases P are not always clear. Here, we report 1.4 Å resolution crystal structure of a novel XPP from Deinococcus radiodurans (XPPdr). XPPdr forms a novel dimeric structure via unique dimer stabilization loops of N-terminal domains such that their C-terminal domains are placed far apart from each other. This novel dimerization is also the consequence of a different orientation of N-terminal domain in XPPdr monomer than those in other known prolidases. The enzymatic assays show that it is a prolidase with broad substrate specificity. Our structural, mutational, and molecular dynamics simulation analyses show that the conserved Arg46 of N-terminal domain is important for the dipeptide selectivity. Our BLAST search found XPPdr orthologs with conserved sequence motifs which correspond to unique structural features of XPPdr, thus identify a new subfamily of bacterial prolidases., (© 2017 Wiley Periodicals, Inc.)

A gamma- and UV radiation-tolerant, Gram-negative, short-rod-shaped bacterial strain, designated X-121 T , was isolated from soil samples collected from the Taklimakan desert in Xinjiang, China. Strain X-121 T showed the highest 16S rRNA gene sequence similarity with Deinococcus depolymerans TDMA-24 T (94.7 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain X-121 T is a member of a novel species belonging to the clade formed by members of the genus Deinococcus in the family Deinococcaceae. The DNA G+C content of strain X-121 T was 63.6 mol%. The chemotaxonomic charateristics of strain X-121 T were typical of members of the genus Deinococcus, with MK-8 being the predominant respiratory quinone, summed feature 3 (16 : 1ω7c,16 : 1ω6c), 16 : 0 and 17 : 1ω8c as major cellular fatty acid, several unidentified phosphoglycolipids and glycolipids as the dominant polar lipids, galactose as the predominant cell-wall sugar and the presence of peptidoglycan with l-ornithine. Strain X-121 T is therefore identified as representing a novel species, for which the name Deinococcus taklimakanensis sp. nov. is proposed, with the type strain X-121 T (=CCTCC AB 207228 T =KCTC 33842 T ).

The extreme radiation resistance of Deinococcus bacteria requires the radiation-stimulated cleavage of protein DdrO by a specific metalloprotease called IrrE. DdrO is the repressor of a predicted radiation/desiccation response (RDR) regulon, composed of radiation-induced genes having a conserved DNA motif (RDRM) in their promoter regions. Here, we showed that addition of zinc ions to purified apo-IrrE, and short exposure of Deinococcus cells to zinc ions, resulted in cleavage of DdrO in vitro and in vivo, respectively. Binding of IrrE to RDRM-containing DNA or interaction of IrrE with DNA-bound DdrO was not observed. The data are in line with IrrE being a zinc peptidase, and indicate that increased zinc availability, caused by oxidative stress, triggers the in vivo cleavage of DdrO unbound to DNA. Transcriptomics and proteomics of Deinococcus deserti confirmed the IrrE-dependent regulation of predicted RDR regulon genes and also revealed additional members of this regulon. Comparative analysis showed that the RDR regulon is largely well conserved in Deinococcus species, but also showed diversity in the regulon composition. Notably, several RDR genes with an important role in radiation resistance in Deinococcus radiodurans, for example pprA, are not conserved in some other radiation-resistant Deinococcus species., (© 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

A Gram-staining positive, non-spore forming, short rod-shaped and coccus-shaped, non-motile, pink-colored, gamma- and UV-resistant strain, designated T93 T was isolated from soil of Malan area in Xinjiang Uyghur Autonomous Region, Northwest China. The taxonomic position of the new isolate was determined using a polyphasic approach. Strain T93 T shared the highest 16 S rRNA gene sequence similarity with Deinococcus deserti VCD115 T (97.54%). The genomic DNA G+C content of the isolate T93 T was 61.7 mol%. The predominant menaquinone was MK-8, while the major cellular fatty acids were iso-C 16:0 , C 15:1 ω6c, C 16:0 , C 17:1 ω8c and Summed Feature 3 (comprising C 16:1 ω7c and/or C 16:1 ω6c). The major polar lipid profiles consisted of diphosphatidylglycerol and phosphatidylinositol mannoside. Based on the phenotypic and genotypic data, strain T93 T is considered to represent a novel species of the genus Deinococcus, for which the name Deinococcus malanensis sp. nov. is proposed. The type strain is T93 T (= KCTC 33563 T  = JCM 30331 T ).

Two Gram-staining-negative, red-pinkish, coccus-shaped, non-motile, and aerobic bacterial strains, designated Ant21 T and Ant22, were isolated from the Antarctic coastal sea water. Strains Ant21 T and Ant22 showed UVC and gamma radiation resistance. Phylogenetic analyses based on 16 S rRNA gene sequences determined that these strains belong to the genus Deinococcus . Through the analyses of the 16 S rRNA gene sequences, strains Ant21 T and Ant22 were found to have 97.7% and 97.8% similarity to Deinococcus marmoris DSM 12784 T and 97.0% and 97.2% similarity to Deinococcus saxicola AA-1444 T , respectively. The sequence similarity with the type strains of other Deinococcus species was less than 96.9% for both strains. Strains Ant21 T and Ant22 shared relatively high 16 S rRNA gene sequence similarity (99.3%) and had a closely related DNA reassociation value of 84 ± 0.5%. Meanwhile, they showed a low level of DNA-DNA hybridization (<30%) with other closely related species of the genus Deinococcus . The two strains also showed typical chemotaxonomic features for the genus Deinococcus , in terms of the major polar lipid (phosphoglycolipid) and the major fatty acids (C 16:0 , C 16:1 ω 6 c / ω 7 c , iso-C 17:0 , and iso-C 15:0 ). They grew at temperatures between 4°C and 30°C and at pH values of 6.0-8.0. Based on the physiological characteristics, the 16S rRNA gene sequence analysis results, and the low DNA-DNA reassociation level with Deionococcus marmoris , strains Ant21 T (= KEMB 9004-167 T =JCM 31436 T ) and Ant22 (KEMB 9004-168 =JCM 31437) represent novel species belonging to the genus Deinococcus , for which the name Deinococcus rubrus is proposed.

Strain 16F3H T , a Gram-negative, aerobic, non-motile, and oval-shaped bacterium, was isolated from river water collected from the Han River in South Korea. Growth of strain 16F3H T was observed at 10-42 °C (optimum at 25-30 °C), but no growth occurred at 4 °C. The strain is able to grow at pH 4-10 (optimum at pH 7-8) and tolerates up to 4% NaCl (w/v), with optimum growth at 0.5% NaCl. The isolate was found to be resistant to UV irradiation. Based on 16S rRNA gene sequence analysis, it is closely related to 'Deinococcus seoulensis' 16F1E (98.8%), Deinococcus aquaticus PB314 T (98.1%) and Deinococcus caeni Ho-08 T (98.0%). The level of DNA-DNA homology between the novel strain and the three related strains was 57.4, 41.2, and 35.8%, respectively. Chemotaxonomic data revealed that strain 16F3H T possesses MK-8 as the predominant respiratory quinone, an unidentified phosphoglycolipid as the major polar lipid, and C 15:1 ω6c and C 16:1 ω7c as the major fatty acids. The DNA G + C content was determined to be 65.7 mol%. Based on polyphasic evidence, strain 16F3H T (=KCTC 33794 T  = JCM 31406 T ) should be classified as the type strain of a novel Deinococcus species, for which the name Deinococcus knuensis sp. nov. is proposed.

Biological soil crusts are distinct habitats, harbor unique prokaryotic diversity and gave an impetus to isolate novel species. In the present study, a pink-pigmented bacterium, (OR316-6 T ), was isolated from biological soil crusts using oligotrophic BG11-PGY medium. Strain OR316-6 T was Gram-positive, short rods, non-motile and non-spore forming. Cells were positive for catalase, oxidase and β-galactosidase and negative for most of the enzymatic activities. The major fatty acids present were C 16:0 , C 17:0 , and C 16:1 ω7c and contained MK-8 and MK-10 as the predominant menaquinones. The cell wall peptidoglycan was of A3β variant with L-ornithine as the diamino acid. Based on the above characteristics, strain OR316-6 T was assigned to the genus Deinococcus. The phylogenetic analysis indicated that strain OR316-6 T was closely related to D. aquatilis DSM 23025 T with a 16S rRNA gene similarity of 99.3 % and clustered with a bootstrap value of 100 %. DNA-DNA similarity between strain OR316-6 T and D. aquatilis DSM 23025 T was 37.0 % indicating that strain OR316-6 T was a novel species. Further, DNA fingerprinting of stains OR316-6 T and D. aquatilis DSM 23035 T demonstrated that both strains were related to each other with a similarity coefficient of only 0.32 and supported the species status to strain OR316-6 T . In addition, phenotypic characteristics distinguished strain OR316-6 T from D. aquatilis DSM 23025 T . Based on the cumulative differences, strain OR316-16 T exhibited with its closely related species, it was identified as a novel species and proposed the name Deinococcus oregonensis sp. nov. The type strain is D. oregonensis sp. nov. (OR316-6 T  = JCM 13503 T  = DSM 17762 T ).

Two gamma- and UVC-resistant bacterial strains, designated JSH3-1T and 9-2-2, were isolated from garden soil in South Korea. Cells were Gram-stain-positive, aerobic, non-motile and spherical. A polyphasic approach was used to study the taxonomic properties of strains JSH3-1T and 9-2-2. Phylogenetic analysis based on nearly full-length 16S rRNA gene sequences of strains JSH3-1T and 9-2-2 indicated highest similarity with Deinococcus radiomollis PO-04-20-132T (94.7 and 94.9 %, respectively); levels of sequence similarity with the type strains of other Deinococcus species were less than 94.0 %. Strains JSH3-1T and 9-2-2 shared relatively high 16S rRNA gene sequence similarity (98.7 %) and had a high DNA reassociation value of 81±0.5 %. Meanwhile, they showed low levels of DNA reassociation (<25 %) with other closely related species of the genus Deinococcus. The two strains showed chemotaxonomic features typical of the genus Deinococcus, with the presence of menaquinone 8 as the respiratory quinone. The predominant fatty acids were iso-C17 : 0, iso-C13 : 0 and anteiso-C13 : 0. The polar lipids comprised phosphoglycolipid, aminophospholipid, glycolipid and unknown aminolipids. The DNA G+C contents of strains JSH3-1T and 9-2-2 were 62.0 and 61.9 mol%, respectively. On the basis of their phenotypic and genotypic characteristics, and phylogenetic distinction, strains JSH3-1T (=KCTC 33790T=JCM 31311T) and 9-2-2 (=KCTC 33789=JCM 31310) should be classified within a novel species of the genus Deinococcus, for which the name Deinococcus ruber sp. nov. is proposed.

Two Gram-stain-negative, oxidase-negative, catalase-positive, aerobic and coccus-shaped bacterial strains, KSY3-6T and JSH6-18, were isolated from soil in South Korea. Strains KSY3-6T and JSH6-18 showed high resistance to gamma-ray and UVC irradiation. The 16S rRNA gene sequences of strains KSY3-6T and JSH6-18 showed a novel subline within the genus Deinococcus in the family Deinococcaceae. They shared 94.8-86.4 % nucleotide similarities with other species of the genus Deinococcus. Strain KSY3-6T exhibited high DNA-DNA hybridization values with JSH6-18 (77±0.8 %). The two strains showed typical chemotaxonomic characteristics of the genus Deinococcus, including the presence of menaquinone 8 (MK-8) as predominant respiratory quinone and C16 : 0, C17 : 0cyclo and summed feature 3 (C16 : 1ω7c/C16: 1ω6c) as major fatty acids. The G+C content of the DNA of strains KSY3-6T and JSH6-18 was 62.0 and 62.4 mol%, respectively. Polar lipids in strains KSY3-6T and JSH6-18 were mainly phosphoglycolipids. Based on their phenotypic and genotypic properties, strains KSY3-6T and JSH6-18 should be classified as representatives of a novel species in the genus Deinococcus, for which the name Deinococcus persicinus sp. nov. is proposed. The type strain is KSY3-6T (=KCTC 33787T=JCM 31313T). The reference strain is JSH6-18 (=KCTC 33788=JCM 31312).

Two gamma- and UV-radiation-resistant, pink-coloured bacterial strains, designated YIM F302T and YIM F235, were isolated from the desert of Yanbu' al Bahr located in west of Saudi Arabia. Taxonomic positions of the two isolates were investigated by polyphasic taxonomic approaches. Cells of the two strains were Gram-stain-negative, aerobic and rod-shaped. They were able to grow at 15-45 °C and pH 6.0-8.0 and had a NaCl tolerance limit of 1 % (w/v). Phylogenetic analyses based on 16S rRNA gene sequences revealed that strains YIM F302T and YIM F235 represent members of the genus Deinococcus, sharing highest sequence similarities of 98.3 and 98.4 %, respectively, with Deinococcus grandis DSM 3963T. The strains were found to contain MK-8 as the respiratory menaquinone. Major fatty acids (>10 %) of the two strains were C15 : 1ω6c, C16 : 0 and C16 : 1ω7c. DNA-DNA hybridization values of the two isolates against the closely related type strains were significantly below the 70 % limit for species delineation. Genomic DNA G+C contents of strains YIM F302T and YIM F235 were 69.3 and 69.0 mol%, respectively. Based on the phenotypic and genotypic characteristics recorded, it is determined that the two isolates represent a novel species of the genus Deinococcus, for which the name Deinococcus saudiensis sp. nov. is proposed. The type strain is YIM F302T (=CGMCC 1.15089T=DSM 29933T).

Two new bacterial strains designated as Ant6 T and Ant18 were isolated from the muscle of a fish which had been caught in the Antarctic Ocean. Both strains are Gram-stain-positive, catalase positive, oxidase negative, aerobic, and coccoid bacteria. Phylogenetic analysis based on the 16S rRNA gene sequences of strains Ant6 T and Ant18 revealed that the strains Ant6 T and Ant18 belong to the genus Deinococcus in the family Deinococcaceae in the class Deinococci. The highest degrees of sequence similarities of strains Ant6 T and Ant18 were found with Deinococcus alpinitundrae LMG 24283 T by 96.4% and 96.8%, respectively. Strain Ant6 T exhibited a high level of DNA- DNA hybridization values with strain Ant18 (82 ± 0.6%). Chemotaxonomic data revealed that the predominant fatty acids were C 17: 0 cyclo, 16:0, and feature 3 (C 16:1 ω6c/ω7c) for both strains. A complex polar lipid profile consisted of major amounts of unknown phosphoglycolipids (PGL) and unknown aminophospholipid (APL). Based on the phylogenetic, phenotypic, and chemotaxonomic data, strains Ant6 T (=KEMB 9004-169 T =JCM 31434 T ) and Ant18 (=KEMB 9004-170) should be classified as a new species, for which the name Deinococcus rubellus sp. nov. is proposed.

Following the exposure of a biofilm sample from a hydrothermal spring cave (Gellért Hill, Budapest, Hungary) to gamma radiation, a strain designated FeSTC15-38T was isolated and studied by polyphasic taxonomic methods. The spherical-shaped cells stained Gram-negative, and were aerobic and non-motile. The pH range for growth was pH 6.0-9.0, with an optimum at pH 7.0. The temperature range for growth was 20-37 °C, with an optimum at 28 °C. Phylogenetic analysis based on the 16S rRNA gene sequence of the isolate indicated that the organism belongs to the genus Deinococcus. The highest sequence similarities appeared with Deinococcus hopiensis KR-140T (94.1 %), Deinococcus aquaticus PB314T (93.3 %) and Deinococcus aerophilus 5516T-11T (92.7 %). The DNA G+C content of the novel strain was 68.2 mol%. The predominant fatty acids (>10 %) were iso-C16 : 0 and C16 : 1ω7c, and the cell-wall peptidoglycan type was A3β l-Orn-Gly2-3, corroborating the assignment of the strain to the genus Deinococcus. Strain FeSTC15-38T contained MK-8 as the major menaquinone and several unidentified phospholipids, glycolipids and phosphoglycolipids. Resistance to gamma radiation (D10) of strain FeSTC15-38T was <3.0 kGy. According to phenotypic and genotypic data, strain FeSTC15-38T represents a novel species for which the name Deinococcus budaensis sp. nov. is proposed. The type strain is FeSTC15-38T (=NCAIM B.02630T=DSM 101791T).

A novel Gram-positive, oval-shaped, non-motile bacterium designated strain 16F1L T was isolated from sediment collected from the Han River in Seoul, Republic of Korea. Based on the 16S rRNA gene sequence (1,448 bp), this strain was identified as a member of the genus Deinococcus that belongs to the class Deinococci. Similarities in the 16S rRNA gene sequence were shown with Deinococcus daejeonensis MJ27 T (99.0%), D. grandis DSM 3963 T (98.1%), D. radiotolerans C1 T (97.5%), and D. caeni Ho-08 T (97.2%). Strain 16F1L T was classified as a different genomic species from closely related Deinococcus members, based on less than 70% DNA-DNA relatedness. Genomic DNA G+C content of strain 16F1L T was 67.2 mol%. Strain 16F1L T was found to grow at temperatures of 10-37°C (optimum 25°C) and pH 7-8 (optimum pH 7) on R2A medium, and was catalase-positive and oxidase-negative. Strain 16F1L T showed resistance to gamma radiation (D 10 > 2 kGy). In addition, this strain had the following chemotaxonomic characteristics: the major fatty acids were C 15:1 ω6c and C 16:1 ω7c; the polar lipid profile contained phosphoglycolipids, unknown aminophospholipids, an unknown aminoglycolipid, unknown aminolipids, an unknown glycolipid, an unknown phospholipid, and an unknown polar lipid; the major quinone was MK-8. Phylogenetic, genotypic, phenotypic, and chemotaxonomic characteristics indicated that strain 16F1L T represents a novel species within the genus Deinococcus, for which the name Deinococcus sedimenti sp. nov. is proposed. The type strain is 16F1L T (=KCTC 33796 T =JCM 31405 T ).

The phylum "Deinococcus-Thermus" contains two heavily researched groups of extremophilic bacteria: the highly radioresistant order Deinococcales and the thermophilic order Thermales. Very few characteristics are known that are uniquely shared by members of the phylum "Deinococcus-Thermus". Comprehensive phylogenetic and comparative analyses of >65 "Deinococcus-Thermus" genomes reported here have identified numerous molecular signatures in the forms of conserved signature insertions/deletions (CSIs) and conserved signature proteins (CSPs), which provide distinguishing characteristics of the phylum "Deinococcus-Thermus" and its main groups. We have identified 58 unique CSIs and 155 unique CSPs that delineate different phylogenetic groups within the phylum. Of these identified traits, 24 CSIs and 29 CSPs are characteristic of the phylum "Deinococcus-Thermus" and they provide novel and reliable means to circumscribe/describe this phylum. An additional 3 CSIs and 3 CSPs are characteristic of the order Deinococcales, and 6 CSIs and 51 CSPs are characteristic of the order Thermales. The remaining 25 CSIs and 72 CSPs identified in this study are distinctive traits of genus level groups within the phylum "Deinococcus-Thermus". The molecular characteristics identified in this work provide novel and independent support for the common ancestry of the members of the phylum "Deinococcus-Thermus" and provide a new means to distinguish the main constituent clades of the phylum. Additionally, the CSIs and CSPs identified in this work may play a role in the unique extremophilic adaptations of the members of this phylum and further functional analyses of these characteristics could provide novel biochemical insights into the unique adaptations found within the phylum "Deinococcus-Thermus"., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

For heterotrophic microorganisms (44 strains) isolated-from the surface film of Lake Baikal, iden- tification was carried out and their. physiological and biochemical characteristics were determined. Com- pared to the water column, diversity of cultured heterotrophs was low, indicating formation of stable micro- bial communities at the air-water interphase interface. Heterotrophic bacteria isolated from the surface mi- crolayer exhibited the enzymatic activity comparable to that for strains form other biofilm associations. Deinococcusfi6us strain NA202 'vas the most active component of the community, capable of utilization of the broadest spectrum of mono- and disaccharides,'sugars, and amino acids. This strain possessed the highest diversity of extracellular enzymes and was the most resistant to UV radiation. The physiological and bio- chemical properties of this strain may-be responsible for its adaptation to survival in extreme conditions of the surface microlayer. Our results improve our understanding of occurrence of UV-resistant strains in freshwater ecosystems.

Strain 16F1E(T) was isolated from a 3-kGy-irradiated sediment sample collected at Han River in Seoul, Republic of Korea. Cells of this strain were observed to be Gram-positive, pililike structure, and short rod shape, and colonies were red in color. The strain showed the highest degree of 16S rRNA gene sequence similarity to Deinococcus aquaticus PB314(T) (98.8%), Deinococcus depolymerans TDMA-24(T) (98.1%), Deinococcus caeni Ho-08(T) (98.0%), and Deinococcus grandis DSM 3963(T) (97.0%). 16S rRNA gene sequence analysis identified this strain as a member of the genus Deinococcus (Family: Deinococcaceae). The genomic DNA G+C content of strain 16F1ET was 66.9 mol%. The low levels of DNA-DNA hybridization (< 56.2%) with the species mentioned above identified strain 16F1E(T) as a novel Deinococcus species. Its oxidase and catalase activities as well as the production of acid from glucose were positive. Growth of the strain was observed at 10-37°C (optimum: 20-30°C) and pH 4-10 (optimum: pH 7-8). The cells tolerated less than 5% NaCl and had low resistance to gamma radiation (D10 < 4 kGy). Strain 16F1ET possessed the following chemotaxonomic characteristics: C16:0, C15:1 ω6c, and C16:1 ω7c as the major fatty acids; phosphoglycolipid as the predominant polar lipid; and menaquinone-8 as the predominant respiratory isoprenoid quinone. Based on the polyphasic evidence, as well as the phylogenetic, genotypic, phenotypic, and chemotaxonomic characterization results, strain 16F1E(T) (=KCTC 33793(T) =JCM 31404(T)) is proposed to represent the type strain of a novel species, Deinococcus seoulensis sp. nov.

A Gram-negative strain, designated SA1(T), was isolated from a sand specimen from Yangyang Beach, South Korea. The cells of SA1(T) were observed to be red pigmented, strictly aerobic, non-motile rods. Strain SA1(T) was found to grow optimally at 30 °C and pH 7 (pH growth range, pH 7-9). Phylogenetic analyses of the 16S rRNA gene sequence of SA1(T) showed that the organism belongs to the phylum Deinococcus-Thermus and forms a branch within the genus Deinococcus, with Deinococcus actinosclerus BM2(T) as a close relative (99.8   % sequence similarity). The strain was found to be catalase positive and oxidase negative and to metabolise 2-ketogluconate, acetate, D,L-3-hydroxybutyrate, D-glucose, D-maltose, D-mannitol, D-mannose, D-melibiose, D-sorbitol, D-sucrose, glycogen, L-alanine, L-histidine, L-malate, L-proline and n-valerate. The guanine plus cytosine (G + C) base composition of the DNA was 69.5 mol %, as determined by the thermal denaturation method. The predominant respiratory quinone was identified as menaquinone with eight isoprene units (MK-8). The polar lipid profile of strain SA1(T) showed the presence of several unidentified glycolipids, phosphoglycolipids, phospholipids, aminophospholipids and unidentified lipids. In addition, the most abundant fatty acids of strain SA1(T) were identified as C15:1 ω6c, C16:1 ω7c and C17:0. On the basis of phylogenetic analyses, DNA-DNA hybridisation and biochemical characteristics, strain SA1(T) (=KCTC 33741(T) = JCM 31047(T)) is concluded to represent a novel species of the genus Deinococcus, for which the name Deinococcus arenae sp. nov. is proposed.

As previous studies mainly focus on understanding the mechanisms of radioresistance in Deinococcus bacteria, the present study aimed at characterizing and verifying the safety use of the GKB-Aid 1995 strain, a member of the radiation-resistant bacterial genus Deinococcus, as an ingredient in feed supplements. Using Vitek 2 system and 16S rRNA gene sequencing, GKB-Aid 1995 most resembles Deinococcus grandis. The Ames test, in vitro chromosomal test, in vivo micronucleus test and acute toxicity test were performed subsequently for its safety evaluation. As there is a possibility that the pigment of GKB-Aid 1995 can pass from feed to eggs intended for human consumption, an acute toxicity test was also carried out in pigmented egg yolk. The results confirmed that GKB-Aid 1995 was non-genotoxic in three genotoxicity experiments, and the LD50 of GKB-Aid 1995 and the pigmented egg yolk in ICR mice was greater than 10 and 12 g kg(-1) body weight, respectively. Overall, these data indicate that GKB-Aid 1995 is a non-toxic substance with no genotoxicity and is therefore safe to be used as a feed supplement or feed additive. This study suggests there is potential in developing GKB-Aid 1995 as an animal feed additive intended to enhance yolk coloration to meet the demand of consumers., (Copyright © 2016 Elsevier Inc. All rights reserved.)

A soil habitat consists of a significant number of bacteria that cannot be cultivated by conventional means, thereby posing obvious difficulties in their classification and identification. This difficulty necessitates the need for advanced techniques wherein a well-compiled biomolecular database consisting of the already cultivable bacteria can be used as a reference in an attempt to link the noncultivable bacteria to their closest phylogenetic groups. Raman spectroscopy has been successfully applied to taxonomic studies of many systems like bacteria, fungi, and plants relying on spectral differences contributed by the variation in their overall biomolecular composition. However, these spectral differences can be obscured due to Raman signatures from photosensitive microbial pigments like carotenoids that show enormous variation in signal intensity hindering taxonomic investigations. In this study, we have applied laser-induced photobleaching to expel the carotenoid signatures from pigmented cocci bacteria. Using this method, we have investigated 12 species of pigmented bacteria abundant in soil habitats belonging to three genera mainly Micrococcus, Deinococcus, and Kocuria based on their Raman spectra with the assistance of a chemometric tool known as the radial kernel support vector machine (SVM). Our results demonstrate the potential of Raman spectroscopy as a minimally invasive taxonomic tool to identify pigmented cocci soil bacteria at a single-cell level.

An aerobic, non-motile and Gram-staining-positive bacterial strain (1PNM-19T) was isolated from a lead-zinc ore in an abandoned mine and was investigated in a taxonomic study using a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain 1PNM-19T was affiliated to the genus Deinococcus and most closely related to Deinococcus aquatilis DSM 23025T and Deinococcus ficus DSM 19119T. The major respiratory quinone was determined to be menaquinone 8 (MK-8) and the major fatty acids contained summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. A complex polar lipid profile consisted of different unidentified glycolipids and polar lipids, two unidentified aminolipids, an unidentified phosphoglycolipid, phospholipid and aminophospholipid. The genomic DNA G+C content of strain 1PNM-19T was 71.7 ± 0.1 mol%. Based on data from this taxonomic study, strain 1PNM-19T represents a novel species of the genus Deinococcus, for which the name Deinococcus metalli sp. nov. is proposed. The type strain is 1PNM-19T ( = GIMCC 1.654T = CCTCC AB 2014198T = DSM 27521T).

Two bacterial strains, designated MA1002(T) and MA1003(T), were isolated from the air-conditioning system of a car. Cells of both strains were Gram-reaction-positive, non-motile, non-spore-forming coccoids, catalase- and oxidase-positive and UV-radiation resistant. The major fatty acids of strain MA1002(T) were iso-C17 : 0 and iso-C15 : 0 and those of strain MA1003(T) were iso-C16 : 0 and iso-C16 : 1 H. The polar lipid profile of MA1002(T) contained phosphatidylethanolamine, two unidentified phosphoglycolipids, an unidentified phospholipid, an unidentified aminophospholipid, an unidentified aminolipid and an unidentified lipid. MA1003(T) had three unidentified phosphoglycolipids, six unidentified phospholipids, two unidentified glycolipids and two unidentified polar lipids as the polar lipids. The G+C contents of the genomic DNA of MA1002(T) and MA1003(T) were 70.5 and 76.0 mol%, respectively. MK-8 was the predominant respiratory quinone for both strains. 16S rRNA gene sequence analysis showed that strain MA1002(T) was phylogenetically related to Deinococcus apachensis DSM 19763(T), D. geothermalis DSM 11300(T), D. aerius TR0125(T) and D. aetherius ST0316(T) (92.9, 92.6, 92.0 and 91.9% sequence similarity, respectively), and MA1003(T) showed the highest sequence similarity to Deinococcus hopiensis KR-140(T) (92.9%) and D. xinjiangensis X-82(T) (91.4%). The results of genotypic and phenotypic characterizations showed that both strains could be distinguished from phylogenetically related species, and that the strains represented novel species within the genus Deinococcus, for which we propose the names Deinococcus metallilatus sp. nov. (type strain MA1002(T) = KACC 17964(T) = NBRC 110141(T)) and Deinococcus carri sp. nov. (type strain is MA1003(T) = KACC 17965(T) = NBRC 110142(T)).

A Gram-positive, coccus-shaped, crimson-color-pigmented bacterium was isolated from soil irradiated with 5 kGy gamma radiation and was designated strain DY1(T). Cells showed growth at 10-30 °C and pH 7-11 and were oxidase-negative and catalase-positive. Phylogenetic analyses of the 16S rRNA gene showed that the strain DY1(T) belonged to the genus Deinococcus with sequence similarities to Deinococcus aquatilis CCUG 53370(T) (96.2 %) and Deinococcus navajonensis KR-114(T) (94.1 %). Strain DY1(T) showed low level of DNA relatedness with D. aquatilis CCUG 53370(T) (41.3 ± 3.9 %). The DNA G + C content of DY1(T) was 58.7 mol%. Predominant fatty acids were summed feature 3 (C16:1 ω7c/ω6c), C16:0, and C17:0. The major amino acids were D-alanine, L-glutamic acid, glycine, and L-ornithine in the peptidoglycan. The major polar lipids were unknown phosphoglycolipids (PGL). Strain DY1(T) has resistance to gamma radiation and was found to be a novel species. Therefore, the strain was designated as DY1(T) (=KCTC 33027(T) = JCM 18576(T)), and the name Deinococcus puniceus sp. nov. is herein proposed.

Two species of the genus Deinococcus, namely Deinococcus wulumuqiensis Wang et al. 2010 and Deinococcus xibeiensis Wang et al. 2010, were simultaneously proposed and described in the same publication. However, the identical 16S rRNA gene sequence of the two type strains strongly raised the probability of their relatedness at the species level. Thus, the genomic relatedness of the two species of the genus Deinococcus was investigated here to clarify their taxonomic status. The high (99.9 %) average nucleotide identity (ANI) between the genome sequences of the two type strains suggested that the two species are synonymous. Additional phenotypic data including enzymic activities and substrate-utilization profiles showed no pronounced differences between the type strains of the two species. Data from this study demonstrated that the two taxa constitute a single species. According to Rule 42 of the Bacteriological Code, we propose that D. xibeiensis Wang et al. 2010 should be reclassified as a subjective heterotypic synonym of D. wulumuqiensis Wang et al. 2010., (© 2015 IUMS.)

Two Gram-negative, non-motile, short rod-shaped bacterial strains, designated as 8A(T) and 28A, were isolated from Mount Deogyusan, Jeonbuk Province, South Korea. The isolates were analyzed by a polyphasic approach, revealing variations in their phenotypic characters but high DNA-DNA hybridisation values reciprocally, confirming that they belong to the same species. Both the isolates also showed a high resistance to UV compared with Deinococcus radiodurans, and a gamma-radiation resistance similar to other members of the genus Deinococcus. Phylogenetic analysis with the 16S rRNA gene sequences of closely related species indicated their similarities were below 97 %. Chemotaxonomic data showed the most abundant fatty acids to be C16:1ω7c and C16:0. The strains can be distinguished from closely related species by the production of esterase (C4) and α-galactosidase, and by their ability to assimilate L-alanine, L-histidine and N-acetyl-D-glucosamine. Based on the phenotypic, phylogenetic, and chemotaxonomic data, the isolates represent a novel species of the genus Deinococcus, for which the name Deinococcus radioresistens sp. nov. is proposed. The type strain is 8A(T) (KEMB 9004-109(T) = JCM 19777(T)), and a second strain is 28A (KEMB 9004-113 = JCM 19778).

A pink-pigmented, non-motile, coccoid bacterial strain, designated G3-6-20(T), was isolated from a soil sample collected in the Grove Mountains, East Antarctica. This strain was resistant to UV irradiation (810 J m(-2)) and slightly more sensitive to desiccation as compared with Deinococcus radiodurans. Phylogenetic analyses based on the 16S rRNA gene sequence of the isolate indicated that the organism belongs to the genus Deinococcus. Highest sequence similarities were with Deinococcus ficus CC-FR2-10(T) (93.5 %), Deinococcus xinjiangensis X-82(T) (92.8 %), Deinococcus indicus Wt/1a(T) (92.5 %), Deinococcus daejeonensis MJ27(T) (92.3 %), Deinococcus wulumuqiensis R-12(T) (92.3 %), Deinococcus aquaticus PB314(T) (92.2 %) and Deinococcus radiodurans DSM 20539(T) (92.2 %). Major fatty acids were C18 : 1ω7c, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), anteiso-C15 : 0 and C16 : 0. The G+C content of the genomic DNA of strain G3-6-20(T) was 63.1 mol%. Menaquinone 8 (MK-8) was the predominant respiratory quinone. Based on its phylogenetic position, and chemotaxonomic and phenotypic characteristics, strain G3-6-20(T) represents a novel species of the genus Deinococcus, for which the name Deinococcus antarcticus sp. nov. is proposed. The type strain is G3-6-20(T) ( = DSM 27864(T) = CCTCC AB 2013263(T))., (© 2015 IUMS.)

A novel pale-pink coloured strain, designated NIO-1023(T), was isolated from a marine sediment sample from Chorao Island, Goa, India. The taxonomic position of strain NIO-1023(T) was investigated by using a polyphasic approach. The cells were observed to be Gram-stain positive, coccal shaped and non-spore forming. Phylogenetic analyses using the 16S rRNA gene sequence of the isolate indicated that the organism belongs to the genus Deinococcus. The strain NIO-1023(T) showed highest 16S rRNA gene sequence similarities with Deinococcus ficus (97.8 %), whereas other Deinococcus species showed less than 95 % sequence similarity. The DNA-DNA relatedness with respect to D. ficus CC-FR2-10(T) was 23.9 %. Chemotaxonomic data revealed that strain NIO-1023(T) contains only menaquinone MK-8 as the respiratory quinone and a complex polar lipid profile consisting of different unidentified glycolipids and polar lipids, two unknown phospholipids and three unknown phosphoglycolipids. As in other deinococci, one of these phosphoglycolipids was predominant in the profile. The predominant fatty acids were identified as C17:1 w8c, C16:1 w6c/w7c, C15:1 w6c and C17:1 w9c. The genomic DNA G + C content of strain NIO-1023(T) was determined to be 67.2 mol%. The biochemical and chemotaxonomic properties demonstrate that strain NIO-1023(T) represents a novel species, for which the name Deinococcus enclensis sp. nov. is proposed. The type strain is NIO-1023(T) (=DSM 25127(T) = NCIM 5456(T)).

A Gram-stain-positive, strictly aerobic, non-motile, coccoid bacterium, designated NCCP-154(T), was isolated from citrus leaf canker lesions and was subjected to a polyphasic taxonomic study. Strain NCCP-154(T) grew at 10-37 °C (optimum 30 °C) and at pH 7.0-8.0 (optimum pH 7.0). The novel strain exhibited tolerance of UV irradiation (>1000 J m(-2)). Based on 16S rRNA gene sequence analysis, strain NCCP-154(T) showed the highest similarity to Deinococcus gobiensis CGMCC 1.7299(T) (98.8 %), and less than 94 % similarity to other closely related taxa. The chemotaxonomic data [major menaquinone, MK-8; cell-wall peptidoglycan type, A3β (Orn-Gly2); major fatty acids, summed feature 3 (C16 : 1ω7c/iso-C15 : 0 2-OH; 35.3 %) followed by C16 : 0 (12.7 %), iso-C17 : 1ω9c (9.2 %), C17 : 1ω8c (7.4 %) and iso-C17 : 0 (6.9 %); major polar lipids made up of several unidentified phosphoglycolipids and glycolipids and an aminophospholipid, and mannose as the predominant whole-cell sugar] also supported the affiliation of strain NCCP-154(T) to the genus Deinococcus. The level of DNA-DNA relatedness between strain NCCP-154(T) and D. gobiensis JCM 16679(T) was 63.3±3.7 %. The DNA G+C content of strain NCCP-154(T) was 70.0 mol%. Based on the phylogenetic analyses, DNA-DNA hybridization and physiological and biochemical characteristics, strain NCCP-154(T) can be differentiated from species with validly published names. Therefore, it represents a novel species of the genus Deinococcus. The name Deinococcus citri sp. nov. is proposed, with the type strain NCCP-154(T) ( = JCM 19024(T) = DSM 24791(T) = KCTC 13793(T))., (© 2014 IUMS.)

A bacterial strain, designated 1P10ME(T), which was resistant to extreme doses of ionizing radiation, pale-pink, non-motile, and a tetrad-forming coccoid was isolated from a cleanroom at the Kennedy Space Center, where the Phoenix spacecraft was assembled. Strain 1P10ME(T) showed optimum growth at 30 °C, with a pH range for growth of 6.5-9.0 and was highly sensitive to sodium chloride, growing only in medium with no added NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 1P10ME(T) represents a novel member of the genus Deinococcus, with low sequence similarities (<93.5%) to recognized species of the genus Deinococcus. The predominant cellular fatty acid was C15:1ω6c. This novel strain exhibits extreme resistance to gamma radiation (D10 >8 kGy) and UV (D10 >1000 Jm(-2)). The results of our polyphasic taxonomic analyses suggest that strain 1P10ME(T) represents a novel species of the genus Deinococcus, for which the name Deinococcus phoenicis sp. nov. is proposed. The type strain is 1P10ME(T) ( = NRRL B-59546(T) = DSM 27173(T))., (© 2014 IUMS.)

A Gram-negative, non-motile, short rod-shaped bacterial strain, designated N5(T), was isolated from a rice field soil in South Korea. Phylogenetic analysis based on the 16S rRNA gene sequence of the new isolate showed that strain N5(T) belongs to the genus Deinococcus, family Deinococcaceae, showing the highest sequence similarity to Deinococcus grandis KACC 11979(T) (98.4 %) and Deinococcus daejeonensis KCTC 13751(T) (97.5 %). Strain N5(T) exhibits resistance to gamma-radiation similar to that of other members of the genus Deinococcus, with a D10 value in excess of 4 kGy. Chemotaxonomic data showed that the most abundant fatty acids are C16:1ω7c (25.25 %), C15:1ω6c (19.77 %), C17:1ω6c (11.87 %), and C17:0 (9.41 %), and the major polar lipid is an unknown phosphoglycolipid. The predominant respiratory quinone is menaquinone MK-8. The DNA G+C content is 71.4 mol%. Phenotypic, phylogenetic, and chemotaxonomic data support designation of strain N5(T) as a novel species of the genus Deinococcus, for which the name Deinococcus soli sp. nov. is proposed. The type strain is N5(T) (=KCTC 33153(T) = JCM 19176(T)).