Deinococcus cellulosilyticus sp. nov., isolated from air

Characterization of airborne microbial communities in northern Thailand: Impacts of smoke haze versus non-haze conditions

Data on airborne microorganisms, particularly in Southeast Asia, are more limited compared to chemical data. This study is the first to examine the community and diversity of microorganisms on PM2.5 in an urban area of Northern Thailand during both smoke haze and non-smoke haze periods of 2020. This study evaluated the composition of airborne bacteria and fungi and analyzed their association with the chemical composition of PM2.5 and meteorological variables. Significantly higher concentrations of PM2.5 and more chemical compounds were observed during the smoke haze period compared to the non-smoke haze period. Increased PM2.5 concentrations significantly altered both bacterial and fungal communities. The diversity and richness of airborne bacteria increased, whereas those of fungi decreased. The level of PM2.5 concentration (the carrier), the chemical composition of PM2.5 (the resources for survival), and the local meteorological conditions (relative humidity (RH)) were associated with the differences in bacterial and fungal populations. In addition, air originating from the west of the receptor site, influenced by both terrestrial and marine air mass routes, contributed to higher bacterial diversity and richness during the smoke haze period. In contrast, fungal diversity and richness were greater when the air came from the southwest, following a marine route. However, the primary health concern is pathogens, which were present in both periods (such as Clostridium, Aspergillus, and Cladosporium) and were especially abundant during smoke haze periods. This study highlights those airborne microorganisms, along with the particles and their chemical composition, are important components that can impact health, including that of humans, animals, and the environment.

Characterization of a unique pH-dependent amylosucrase from Deinococcus cellulosilyticus

The amylosucrase (ASase, EC 2.4.1.4) utilizes sucrose as the sole substrate to catalyze multifunctional reactions. It can naturally synthesize α-1,4-linked glucans such as amylose as well as sucrose isomers with more favorable properties than sucrose with a lower intestinal digestibility and non-cariogenic properties. The amino acid sequence of the asase gene from Deinococcus cellulosilyticus (DceAS) exhibits low homology with those of other ASases from other Deinococcus species. In this study, we cloned and expressed DceAS and demonstrated its high activity at pH 6 and pH 8 and maintained stability. It showed higher polymerization activity at pH 6 than at pH 8, but similar isomerization activity and produced more turanose and trehalulose at pH 6 than at pH 8 and produced more isomaltulose at pH 8. Furthermore, the molecular weight of DceAS was 226.6 kDa at pH 6 and 145.5 kDa at pH 8, indicating that it existed as a trimer and dimer, respectively under those conditions. Additionally, circular dichroism spectra showed that the DceAS secondary structure was different at pH 6 and pH 8. These differences in reaction products at different pHs can be harnessed to naturally produce sucrose alternatives that are more beneficial to human health.

Deinococcus aestuarii sp. nov. and Deinococcus aquaedulcis sp. nov., two novel resistant bacteria isolated from pearl river estuary

Two novel species of the genus Deinococcus, designated SYSU M49105^T and SYSU M42101^T, were isolated from freshwater samples of the Pearl River estuary in Guangdong, China. Phylogenetic analysis using 16S rRNA gene sequence indicated that strains SYSU M49105^T and SYSU M42101^T showed the highest sequence similarities to Deinococcus aetherius JCM 11751 ^T (93.6%) and Deinococcus multiflagellatus NBRC 112888 ^T (97.3%), respectively. Cells of both strains were Gram-staining positive, aerobic, coccus-shaped, oxidase-negative and non-motile. The cell wall contained meso-diaminopimelic acid as their diagnostic diamino acid. MK-8 was the predominant respiratory quinone for both strains. The polar lipid profile of SYSU M49105^T contained two unidentified phosphoglycolipids, nine unidentified glycolipids, and five unidentified polar lipids. SYSU M42101^T had one unidentified phosphoglycolipid, nine unidentified glycolipids, one unidentified aminophospholipid and four unidentified polar lipids. The major fatty acids of strains SYSU M49105^T and SYSU M42101^T were summed feature 3 (C_16:1 ω7c and/ or C_16:1 ω6c) and C_16:0. The G + C contents of the novel isolates based on genomic DNAs were 69.6% and 67.4%, respectively. On the basis of phenotypic, genotypic and phylogenetic data, strains SYSU M49105^T and SYSU M42101^T should be considered to represent two novel species in the genus Deinococcus, for which the names Deinococcus aestuarii sp. nov. and Deinococcus aquaedulcis sp. nov. were proposed with the type strains SYSU M49105^T (= KCTC 43258 ^T = CGMCC 1.18609 ^T) and SYSU M42101^T (= KCTC 43257 ^T = CGMCC 1.18614 ^T), respectively.

A new era of radiation resistance bacteria in bioremediation and production of bioactive compounds with therapeutic potential and other aspects: An in-perspective review

Microorganisms that survive in extreme environmental conditions are known as 'extremophiles'. Recently, extremophiles draw an impression in biotechnology/pharmaceutical researches/industries because of their novel molecules, known as 'extremolytes'. The intriguing phenomenon of microbial radiation resistance probably arose independently throughout their evolution of selective pressures (e.g. UV, X-ray, Gamma radiation etc.). Radiation produces multiple types of damage/oxidation to nucleic acids, proteins and other crucial cellular components. Most of the literature on microbial radiation resistance is based on acute γ-irradiation experiments performed in the laboratory, typically involving pure cultures isolation and their application on bioremediation/therapeutic field. There is much less information other than bioremediation and therapeutic application of such promising microbes we called as 'new era'. Here we discus origin and diversity of radiation resistance bacteria as well as selective mechanisms by which microorganisms can sustain in radiation rich environment. Potential uses of these radiations resistant microbes in the field of bioremediation, bioactive compounds and therapeutic industry. Last but not the least, which is the new aspect of radiation resistance microbes. Our review suggest that resistance to chronic radiation is not limited to rare specialized strains from extreme environments, but can occur among common microbial taxa, perhaps due to overlap molecular mechanisms of resistance to radiation and other stressors. These stress tolerance potential make them potential for radionuclides remediation, their extremolytes can be useful as anti-oxidant and anti-proliferative agents. In current scenario they can be useful in various fields from natural dye synthesis to nanoparticles production and anti-cancer treatment.

Amino Acid-Dependent Alterations in Cell Wall and Cell Morphology of Deinococcus indicus DR1

Deinococcus radiodurans exhibits growth medium-dependent morphological variation in cell shape, but there is no evidence whether this phenomenon is observed in other members of the Deinococcaceae family. In this study, we isolated a red-pigmented, aerobic, Deinococcus indicus strain DR1 from Dadri wetland, India. This D. indicus strain exhibited cell–morphology transition from rod-shaped cells to multi-cell chains in a growth-medium-dependent fashion. In response to addition of 1% casamino acids in the minimal growth medium, rod-shaped cells formed multi-cell chains. Addition of all 20 amino acids to the minimal medium was able to recapitulate the phenotype. Specifically, a combination of L-methionine, L-lysine, L-aspartate, and L-threonine caused morphological alterations. The transition from rod shape to multi-cell chains is due to delay in daughter cell separation after cell division. Minimal medium supplemented with L-ornithine alone was able to cause cell morphology changes. Furthermore, a comparative UPLC analysis of PG fragments isolated from D. indicus cells propagated in different growth media revealed alterations in the PG composition. An increase in the overall cross-linkage of PG was observed in muropeptides from nutrient-rich TSB and NB media versus PYE medium. Overall our study highlights that environmental conditions influence PG composition and cell morphology in D. indicus.

Source Community and Assembly Processes Affect the Efficiency of Microbial Microcystin Degradation on Drinking Water Filtration Membranes

Microbial biofilms in gravity-driven membrane (GDM) filtration systems can efficiently degrade the cyanotoxin microcystin (MC), but it is unclear if this function depends on the presence of MC-producing cyanobacteria in the source water habitat. We assessed the removal of MC from added Microcystis aeruginosa biomass in GDMs fed with water from a lake with regular blooms of toxic cyanobacteria (ExpL) or from a stream without such background (ExpS). While initial MC removal was exclusively due to abiotic processes, significantly higher biological MC removal was observed in ExpL. By contrast, there was no difference in MC degradation capacity between lake and stream bacteria in separately conducted liquid enrichments on pure MC. Co-occurrence network analysis revealed a pronounced modularity of the biofilm communities, with a clear hierarchic distinction according to feed water origin and treatment type. Genotypes in the network modules associated with ExpS had significantly more links to each other, indicating that these biofilms had assembled from a more coherent source community. In turn, signals for stochastic community assembly were stronger in ExpL biofilms. We propose that the less "tightly knit" ExpL biofilm assemblages allowed for the better establishment of facultatively MC degrading bacteria, and thus for higher overall functional efficiency.

MALDI-TOF MS Affords Discrimination of Deinococcus aquaticus Isolates Obtained From Diverse Biofilm Habitats

Matrix-assisted Laser Desorption Ionization-Time of Flight Mass Spectroscopy (MALDI-TOF MS) has been used routinely over the past decade in clinical microbiology laboratories to rapidly characterize diverse microorganisms of medical importance both at the genus and species levels. Currently, there is keen interest in applying MALDI-TOF MS at taxonomic levels beyond species and to characterize environmental isolates. We constructed a model system consisting of 19 isolates of Deinococcus aquaticus obtained from biofilm communities indigenous to diverse substrates (concrete, leaf tissue, metal, and wood) in the Fox River - Lake Winnebago system of Wisconsin to: (1) develop rapid sample preparation methods that produce high quality, reproducible MALDI-TOF spectra and (2) compare the performance of MALDI-TOF MS-based profiling to common DNA-based approaches including 16S rRNA sequencing and genomic diversity by BOX-A1R fingerprinting. Our results suggest that MALDI-TOF MS can be used to rapidly and reproducibly characterize environmental isolates of D. aquaticus at the subpopulation level. MALDI-TOF MS provided higher taxonomic resolution than either 16S rRNA gene sequence analysis or BOX-A1R fingerprinting. Spectra contained features that appeared to permit characterization of isolates into two co-occurring subpopulations. However, reliable strain-level performance required rigorous and systematic standardization of culture conditions and sample preparation. Our work suggests that MALDI-TOF MS offers promise as a rapid, reproducible, and high-resolution approach to characterize environmental isolates of members of the genus Deinococcus. Future work will focus upon application of methods described here to additional members of this ecologically diverse and ubiquitous genus.

Deinococcus aluminii sp. nov., isolated from an automobile air conditioning system

A Gram-stain-positive and pale pink-pigmented bacterial strain, designated ID0501^T, was isolated from an automobile evaporator core collected in the Republic of Korea. The cells were aerobic and coccoidal. The strain grew at 15-40 ˚C (optimum, 37 ˚C), at pH 6.0-7.0 (optimum, pH 6.5), and in the presence of 0-1.5 % (w/v) NaCl. Phylogenetically, the strain was related to members of the genus Deinococcus and showed the highest sequence similarity, of 96.9 %, with Deinococcus metallilatus MA1002^T. The major fatty acids of the strain were iso-C_17 : 0, iso-C_15 : 0 and iso-C_13 : 0. The predominant respiratory quinone was MK-8. The polar lipids profile revealed the presence of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, diphosphatidylglycerol, unidentified phospholipids, an unidentified aminolipid and unidentified glycolipids. The DNA G+C content of the strain was 68.3 mol%. On the basis of phenotypic, genotypic and chemotaxonomic data, strain ID0501^T represents a novel species of the genus Deinococcus, for which the name Deinococcusaluminii sp. nov. (=KACC 19286^T=NBRC 112889^T) is proposed.

Deinococcus multiflagellatus sp. nov., isolated from a car air-conditioning system

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.

Deinococcus saudiensis sp. nov., isolated from desert

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).

Description of Deinococcus oregonensis sp. nov., from biological soil crusts in the Southwestern arid lands of the United States of America

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_16:1ω7c 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).

Deinococcus seoulensis sp. nov., a bacterium isolated from sediment at Han River in Seoul, Republic of Korea

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.

Deinococcus metallilatus sp. nov. and Deinococcus carri sp. nov., isolated from a car air-conditioning system

Two bacterial strains, designated MA1002T and MA1003T, 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 MA1002T were iso-C17 : 0 and iso-C15 : 0 and those of strain MA1003T were iso-C16 : 0 and iso-C16 : 1 H. The polar lipid profile of MA1002T contained phosphatidylethanolamine, two unidentified phosphoglycolipids, an unidentified phospholipid, an unidentified aminophospholipid, an unidentified aminolipid and an unidentified lipid. MA1003T 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 MA1002T and MA1003T 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 MA1002T was phylogenetically related to Deinococcus apachensis DSM 19763T, D. geothermalis DSM 11300T, D. aerius TR0125T and D. aetherius ST0316T (92.9, 92.6, 92.0 and 91.9 % sequence similarity, respectively), and MA1003T showed the highest sequence similarity to Deinococcus hopiensis KR-140T (92.9 %) and D. xinjiangensis X-82T (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 MA1002T = KACC 17964T = NBRC 110141T) and Deinococcus carri sp. nov. (type strain is MA1003T = KACC 17965T = NBRC 110142T).

Deinococcus as new chassis for industrial biotechnology: biology, physiology and tools

Deinococcus spp are among the most radiation-resistant micro-organisms that have been discovered. They show remarkable resistance to a range of damage caused by ionizing radiation, desiccation, UV radiation and oxidizing agents. Traditionally, Escherichia coli and Saccharomyces cerevisiae have been the two platforms of choice for engineering micro-organisms for biotechnological applications, because they are well understood and easy to work with. However, in recent years, researchers have begun using Deinococcus spp in biotechnologies and bioremediation due to their specific ability to grow and express novel engineered functions. More recently, the sequencing of several Deinococcus spp and comparative genomic analysis have provided new insight into the potential of this genus. Features such as the accumulation of genes encoding cell cleaning systems that eliminate organic and inorganic cell toxic components are widespread among Deinococcus spp. Other features such as the ability to degrade and metabolize sugars and polymeric sugars make Deinococcus spp. an attractive alternative for use in industrial biotechnology.

Deinococcus antarcticus sp. nov., isolated from soil

A pink-pigmented, non-motile, coccoid bacterial strain, designated G3-6-20T, 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-FR2-10T (93.5 %), Deinococcus xinjiangensis X-82T (92.8 %), Deinococcus indicus Wt/1aT (92.5 %), Deinococcus daejeonensis MJ27T (92.3 %), Deinococcus wulumuqiensis R-12T (92.3 %), Deinococcus aquaticus PB314T (92.2 %) and Deinococcus radiodurans DSM 20539T (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 G3-6-20T was 63.1 mol%. Menaquinone 8 (MK-8) was the predominant respiratory quinone. Based on its phylogenetic position, and chemotaxonomic and phenotypic characteristics, strain G3-6-20T represents a novel species of the genus Deinococcus , for which the name Deinococcus antarcticus sp. nov. is proposed. The type strain is G3-6-20T ( = DSM 27864T = CCTCC AB 2013263T).

Radiation-resistant extremophiles and their potential in biotechnology and therapeutics

Extremophiles are organisms able to thrive in extreme environmental conditions. Microorganisms with the ability to survive high doses of radiation are known as radioresistant or radiation-resistant extremophiles. Excessive or intense exposure to radiation (i.e., gamma rays, X-rays, and particularly UV radiation) can induce a variety of mutagenic and cytotoxic DNA lesions, which can lead to different forms of cancer. However, some populations of microorganisms thrive under different types of radiation due to defensive mechanisms provided by primary and secondary metabolic products, i.e., extremolytes and extremozymes. Extremolytes (including scytonemin, mycosporine-like amino acids, shinorine, porphyra-334, palythine, biopterin, and phlorotannin, among others) are able to absorb a wide spectrum of radiation while protecting the organism's DNA from being damaged. The possible commercial applications of extremolytes include anticancer drugs, antioxidants, cell-cycle-blocking agents, and sunscreens, among others. This article aims to review the strategies by which microorganisms thrive in extreme radiation environments and discuss their potential uses in biotechnology and the therapeutic industry. The major challenges that lie ahead are also discussed.

Deinococcus humi sp. nov., isolated from soil

A Gram-staining-positive, strictly aerobic, spherical, non-motile, red-pigmented bacterium, designated strain MK03T, was isolated from a soil sample collected in South Korea. The taxonomic position of the novel strain was investigated using a polyphasic approach. In phylogenetic analyses based on 16S rRNA gene sequences, strain MK03T was placed in a clade formed by members of the genus Deinococcus in the family Deinococcaceae and appeared to be most closely related to Deinococcus aerolatus 5516T-9T (97.4 % sequence similarity), Deinococcus marmoris AA-63T (97.2 %), Deinococcus radiopugnans ATCC 19172T (97.2 %) and Deinococcus saxicola AA-1444T (96.9 %). The genomic DNA G+C content of the novel strain was 64.5 mol%. The chemotaxonomic characteristics of strain MK03T were typical of members of the genus Deinococcus : MK-8 was identified as the predominant respiratory quinine, the major fatty acids were C16 : 1ω7c, C15 : 1ω6c, C16 : 0 and C15 : 0, ornithine was found to be the diamino acid in the cell-wall peptidoglycan and the novel strain showed resistance to gamma radiation, with a D10 value (i.e. the dose required to reduce the bacterial population by 10-fold) in excess of 9 kGy. In hybridization experiments, only low DNA–DNA relatedness values (11.6–34.5 %) were recorded between the novel strain and its closest relatives in the genus Deinococcus . Based on the phylogenetic, chemotaxonomic, phenotypic and DNA–DNA relatedness data, strain MK03T represents a novel species of the genus Deinococcus , for which the name Deinococcus humi sp. nov. is proposed. The type strain is MK03T ( = KCTC 13619T  = JCM 17915T).

Deinococcus daejeonensis sp. nov., isolated from sludge in a sewage disposal plant

A Gram-stain-positive, strictly aerobic, spherical, non-motile red-pigmented bacterial strain, designated MJ27T, was isolated from a sludge sample of the Daejeon sewage disposal plant in South Korea. A polyphasic approach was used to study the taxonomic position of strain MJ27T. Strain MJ27T shared highest 16S rRNA gene sequence similarity with Deinococcus grandis DSM 3963T (98.8 %), Deinococcus caeni Ho-08T (97.5 %) and Deinococcus aquaticus PB314T (96.6 %.); levels of sequence similarity with the type strains of other Deinococcus species were less than 96.0 %. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MJ27T belonged to the clade formed by members of the genus Deinococcus in the family Deinococcaceae . The G+C content of the genomic DNA of strain MJ27T was 67.6 mol%. The chemotaxonomic characteristics of strain MJ27T were typical of members of the genus Deinococcus , with MK-8 as the predominant respiratory quinone, C16 : 1ω7c, C15 : 1ω6c, C16 : 0 and C15 : 0 as major fatty acids (>12 %), ornithine as the diamino acid in the cell-wall peptidoglycan and resistance to gamma radiation [D10 (dose required to reduce the bacterial population by tenfold) >9 kGy]. The low levels of DNA–DNA relatedness reported here (5.3±1.5–29.2±2.3 %) indicate that strain MJ27T represents a species that is separate from its closest relatives in the genus Deinococcus . On the basis of phylogenetic inference, fatty acid profile and other phenotypic properties, strain MJ27T is considered to represent a novel species of the genus Deinococcus , for which the name Deinococcus daejeonensis sp. nov. is proposed. The type strain is MJ27T ( = KCTC 13751T = JCM 16918T).

Characterization of Deinococcus sahariens sp. nov., a radiation-resistant bacterium isolated from a Saharan hot spring

An ultraviolet-radiation-resistant, Gram-positive, orange-pigmented, thermophilic and strictly aerobic cocci was isolated from Saharan water hot spring in Tunisia. The newly isolated bacterium, designated HAN-23(T), was identified based on polyphasic taxonomy including genotypic, phenotypic and chemotaxonomic characterization. Phylogenetic analysis based on 16S rRNA gene sequences placed this strain within Deinococcus genus. However, strain HAN-23(T) is different from recognized species of the genus Deinococcus, showing less than 94.0% similarity values to its closest relatives. The predominant cellular fatty acids determined by gas chromatography were iso-C(15:0), iso-C(17:0) and iso C(17:1) ω9c. The major respiratory quinone was MK-8. The DNA G + C content was 66.9 mol%. DNA-DNA hybridization measurements revealed low DNA relatedness (6%) between the novel isolate and its closest neighbor, the type strain Deinococcus geothermalis DSM 11300. On the basis of the phenotypic, chemotaxonomic and phylogenetic data, strain HAN-23(T) represents a novel species of the genus Deinococcus, for which the name Deinococcus sahariens sp. nov. is proposed, the type strain being HAN-23(T) (=DSM 18496(T); LMG 23756(T)).

Complete genome sequence of Deinococcus maricopensis type strain (LB-34)

Deinococcus maricopensis (Rainey and da Costa 2005) is a member of the genus Deinococcus, which is comprised of 44 validly named species and is located within the deeply branching bacterial phylum Deinococcus-Thermus. Strain LB-34(T) was isolated from a soil sample from the Sonoran Desert in Arizona. Various species of the genus Deinococcus are characterized by extreme radiation resistance, with D. maricopensis being resistant in excess of 10 kGy. Even though the genomes of three Deinococcus species, D. radiodurans, D. geothermalis and D. deserti, have already been published, no special physiological characteristic is currently known that is unique to this group. It is therefore of special interest to analyze the genomes of additional species of the genus Deinococcus to better understand how these species adapted to gamma- or UV ionizing-radiation. The 3,498,530 bp long genome of D. maricopensis with its 3,301 protein-coding and 66 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

Deinococcus reticulitermitis sp. nov., isolated from a termite gut

Bacterial strain TM-1(T) was isolated from the gut of a wood-feeding termite, Reticulitermes chinensis Snyder. Cells of strain TM-1(T) were Gram-negative, spherical (1.0-2.0 µm in diameter), non-motile, non-sporulating and red-pigmented. Strain TM-1(T) was resistant to UV radiation, showing 34% survival after exposure to UV light at a dose of 100 J m(-2). Growth occurred at 20-40 °C (optimum, 30 °C), at pH 6.0-10.0 (optimum, pH 6.0-7.0), and in the presence of 0-1% (w/v) NaCl (optimum, 0-0.4%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain TM-1(T) was related to members of the genus Deinococcus, with sequence similarities ranging from 87.0 to 94.0%. The peptidoglycan of strain TM-1(T) contained ornithine, alanine, glycine and glutamic acid. The most abundant cellular fatty acids of strain TM-1(T) were summed feature 3 (C(16:1)ω7c and/or C(16:1)ω6c; 22.3%) and C(16:0) (37.5%). MK-8 was the predominant quinone. The polar lipid profile contained three glycophospholipids, six glycolipids, one aminolipid and three unknown lipids. DNA of the type strain had a G+C content of 65.6 mol%. Based on the phylogenetic, chemotaxonomic and phenotypic data presented, strain TM-1(T) represents a novel species of the genus Deinococcus, for which the name Deinococcus reticulitermitis sp. nov. is proposed, with TM-1(T) (=CGMCC 1.10218(T)=NBRC 106334(T)) as the type strain.

Composition of the bacterial biota in slime developed in two machines at a Canadian paper mill

During the process of papermaking by pulp and paper plants, a thick and viscous deposits, termed slime, is quickly formed around the paper machines, which can affect the papermaking process. In this study, we explored the composition of the bacterial biota in slime that developed on shower pipes from 2 machines at a Canadian paper mill. Firstly, the composition was assessed for 12 months by DNA profiling with polymerase chain reaction coupled with denaturing gradient gel electrophoresis. Except for short periods (2–3 months), clustered analyses showed that the bacterial composition of the slime varied substantially over the year, with less than 50% similarity between the denaturing gradient gel electrophoresis profiles. Secondly, the screening of 16S rRNA gene libraries derived from 2 slime samples showed that the most abundant bacteria were related to 6 lineages, including Chloroflexi, candidate division OP10, Clostridiales, Bacillales, Burkholderiales, and the genus Deinococcus . Finally, the proportion of 8 bacterial lineages, such as Deinococcus sp., Meiothermus sp., and Chloroflexi, was determined by the Catalyzed Reporter Deposition – Fluorescence In Situ Hybridization in 2 slime samples. The results showed a high proportion of Chloroflexi, Tepidimonas spp., and Schlegelella spp. in the slime samples.

Deinococcus wulumuqiensis sp. nov., and Deinococcus xibeiensis sp. nov., isolated from radiation-polluted soil

The taxonomic positions of two gamma- and UV-ray-resistant strains isolated from radiation-polluted soil in north-west China were determined in a polyphasic study. The organisms, designated R12T and R13T, were Gram-stain-positive, non-spore-forming cocci, which contained MK-8 as the major respiratory quinone and C16 : 1 ω7c and C16 : 0 as major fatty acids. The cell walls of strains R12T and R13T contained ornithine. Phylogenetic analysis based on 16S rRNA gene sequences and DNA–DNA hybridizations showed that strains R12T and R13T are members of novel species belonging to the genus Deinococcus, with Deinococcus radiodurans DSM 20539T as the closest relative. The isolates R12T and R13T shared 97 and 97.1 % 16S rRNA gene similarity, respectively, and 29.5 and 33.3 % DNA–DNA relatedness, respectively, with D. radiodurans DSM 20539T. The DNA G+C contents of isolates R12T and R13T were 66.7 and 63.8 %, respectively. On the basis of phenotypic tests and other results, two species, Deinococcus wulumuqiensis sp. nov. (type strain R12T =CGMCC 1.8884T =NBRC 105665T) and Deinococcus xibeiensis sp. nov. (type strain R13T =CGMCC 1.8885T =NBRC 105666T), are proposed.

Deinobacterium chartae gen. nov., sp. nov., an extremely radiation-resistant, biofilm-forming bacterium isolated from a Finnish paper mill

A rod-shaped, non-spore-forming, non-motile, aerobic, oxidase and catalase-positive and radiation-resistant bacterium (designated strain K4.1(T)) was isolated from biofilm collected from a Finnish paper mill. The bacterium grew as pale pink colonies on oligotrophic medium at 12 to 50 °C (optimum 37 to 45 °C) and at pH 6 to 10.3. The DNA G+C content of the strain was 66.8 l%. According to 16S rRNA gene sequence analysis, strain K4.1(T) was distantly related to the genus Deinococcus, sharing highest similarity with Deinococcus pimensis (90.0  %). In the phylogenetic tree, strain K4.1(T) formed a separate branch in the vicinity of the genus Deinococcus. The peptidoglycan type was A3β with L-Orn-Gly-Gly and the quinone system was determined to be MK-8. The polar lipid profile of strain K4.1(T) differed markedly from that of the genus Deinococcus. The predominant lipid of strain K4.1(T) was an unknown aminophospholipid and it did not contain the unknown phosphoglycolipid predominant in the polar lipid profiles of deinococci analysed to date. Two of the predominant fatty acids of the strain, 15 : 0 anteiso and 17 : 0 anteiso, were lacking or present in small amounts in species of the genus Deinococcus. Phylogenetic distinctness and significant differences in the polar lipid and fatty acid profiles suggest classification of strain K4.1(T) as a novel genus and species in the family Deinococcaceae, for which we propose the name Deinobacterium chartae gen. nov., sp. nov. The type strain is K4.1(T) (=DSM 21458(T) =HAMBI 2721(T)).

Deinococcus aetherius sp. nov., isolated from the stratosphere

A pink-red pigmented, non-motile, coccoid bacterial strain, ST0316T, was isolated from dust samples collected from the stratosphere in Japan. Phylogenetic analysis based on 16S rRNA gene sequences showed that it belonged to the genus Deinococcus. DNA G+C content (69.8 mol%), desiccation tolerance, and resistance to gamma-rays [D10 (dose required to reduce the bacterial population by 10-fold) >8 kGy] and UV radiation (D10 1000 J m−2) supported the affiliation of strain ST0316T to the genus Deinococcus. The major peptidoglycan amino acids were d-glutamic acid, glycine, d-alanine, l-alanine and ornithine. Predominant fatty acids were C16 : 1 ω7c, C16 : 0, C17 : 0 and iso-C17 : 0. Strain ST0316T diverged from recognized species of the genus Deinococcus, showing less than 93.0 % similarity values to its closest relatives Deinococcus apachensis, D. aerius, D. geothermalis and D. murrayi. Strain ST0316T also differed from the type strains of closely related species in its polar lipid profile, nitrate reduction and carbon-source assimilation tests. Therefore, we propose a new species of the genus Deinococcus, Deinococcus aetherius sp. nov. (type strain, ST0316T =JCM 11751T =DSM 21230T).

Deinococcus aerolatus sp. nov. and Deinococcus aerophilus sp. nov., isolated from air samples

Two strains of pink-coloured bacteria, 5516T-9(T) and 5516T-11(T), were isolated from an air sample collected in Korea. The taxonomic status of these novel strains was investigated by means of a polyphasic approach. The novel strains were Gram-positive, aerobic, non-spore-forming and coccus-shaped bacteria. The DNA G+C contents of strains 5516T-9(T) and 5516T-11(T) were 61.0 and 59.3 mol%, respectively. The major isoprenoid quinone for both strains was MK-8. Strain 5516T-9(T) contained summed feature 3 (iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c), C(16 : 0) and iso-C(17 : 1)omega9c, and strain 5516T-11(T) contained summed feature 3, iso-C(17 : 1)omega9c, C(17 : 1)omega8c and C(15 : 1)omega6c as the major fatty acids (>10 %). The polar lipid patterns of both strains were similar, comprising one phospholipid and one aminophospholipid as the major components. Phylogenetic analyses using 16S rRNA gene sequences showed that both novel strains were affiliated to the genus Deinococcus. Strain 5516T-9(T) exhibited the highest sequence similarity with Deinococcus marmoris DSM 12784(T) (96.8 %) and strain 5516T-11(T) showed the highest sequence similarity with Deinococcus saxicola DSM 15974(T) (94.5 %). The sequence similarity between strains 5516T-9(T) and 5516T-11(T) was 94.7 %. On the basis of the data presented, it is evident that both strains represent separate novel species of the genus Deinococcus for which the names Deinococcus aerolatus sp. nov. (type strain 5516T-9(T)=KACC 12745(T)=JCM 15442(T)) and Deinococcus aerophilus sp. nov. (type strain 5516T-11(T)=KACC 12746(T)=JCM 15443(T)) are proposed.

Deinococcus gobiensis sp. nov., an extremely radiation-resistant bacterium

A Gram-positive, non-motile, spherical, red-pigmented and facultatively anaerobic bacterium, designated strain I-0(T), was isolated from a sand sample of the Gobi desert in Xinjiang Autonomous Region, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that this isolate represents a novel member of the genus Deinococcus, with low sequence similarities (<94 %) to recognized Deinococcus species. The major cellular fatty acids were C(16 : 1)omega7c and C(16 : 0). Its polar lipid profile contained several unidentified glycolipids, phosphoglycolipids, phospholipids, pigments and an aminophospholipid. The peptidoglycan type was Orn-Gly(2) (A3beta) and the predominant respiratory quinone was MK-8. The DNA G+C content was 65.4 mol%. DNA-DNA relatedness between strain I-0(T) and Deinococcus radiodurans ACCC 10492(T) was 37 %. The strain was shown to be extremely resistant to gamma radiation (>15 kGy) and UV light (>600 J m(-2)). On the basis of the phylogenetic, chemotaxonomic and phenotypic data presented, strain I-0(T) represents a novel species of the genus Deinococcus, for which the name Deinococcus gobiensis sp. nov. is proposed. The type strain is I-0(T) (=DSM 21396(T) =CGMCC 1.7299(T)).

Deinococcus aquaticus sp. nov., isolated from fresh water, and Deinococcus caeni sp. nov., isolated from activated sludge

The taxonomic positions of two environmental isolates from South Korea were established using a combination of genotypic and phenotypic data. The organisms, designated PB314(T) and Ho-08(T), were Gram-negative, rod-shaped and non-spore-forming and had chemotaxonomic properties consistent with their classification in the genus Deinococcus 16S rRNA gene tree, the highest sequence similarities being shown to the type strains of Deinococcus grandis (96.3-96.7 %) and Deinococcus indicus (96.3-96.4 %). The isolates shared relatively high 16S rRNA gene sequence similarity (98.1 %) but had a DNA-DNA relatedness value of only 22 %. Chemotaxonomic data revealed that both strains possess quinone system MK-8 as the predominant compound, C(16 : 1)omega7c and C(16 : 0) as major fatty acids and ornithine as a diamino acid in the peptidoglycan structure, corroborating our assignment of the strains to the genus Deinococcus. The results of phylogenetic analyses based on 16S rRNA gene sequences, DNA-DNA relatedness values and physiological and biochemical tests clearly demonstrated that the two strains represent distinct species. On the basis of these data, two novel species, Deinococcus aquaticus sp. nov. (type strain PB314(T) =KCTC 12552(T) =NBRC 101311(T)) and Deinococcus caeni sp. nov. (type strain Ho-08(T) =KCTC 12553(T) =NBRC 101312(T)), are proposed.