Sphingomonas xinjiangensis sp. nov., isolated from desert sand

Ultraviolet Resistance of Microorganisms Isolated from Uranium-Rich Minerals from Perus, Brazil

The district of Perus, located in the city of São Paulo, Brazil, is renowned for its weathered granitic-pegmatitic masses, which harbor a significant number of uraniferous minerals that contribute to ionizing radiation levels up to 20 times higher than the background levels. In this study, aseptically collected mineral samples from the area were utilized to isolate 15 microorganisms, which were subjected to pre-screening tests involving UV-C and UV-B radiation. The microorganisms that exhibited the highest resistance to ultraviolet (UV) radiation were selected for the construction of survival curves for UV-C, broad-band UV-B, and solar simulation resistance testing. Subsequently, the four strains that demonstrated superior survival capabilities under UV radiation exposure were chosen for 16S rRNA gene sequencing. Among these, Nocardioides sp. O4R and Nocardioides sp. MA2R demonstrated the most promising outcomes in the UV radiation resistance assessments, showcasing comparable performance to the well-established radioresistant model organism Deinococcus radiodurans. These findings underscore the potential of naturally occurring high-radiation environments as valuable resources for the investigation of UV-resistant microorganisms.

Sphingomonas cannabina sp. nov., isolated from Cannabis sativa L. 'Cheungsam'

A Gram-negative, aerobic, rod-shaped bacterium, designated DM2-R-LB4^T was isolated from Cannabis sativa L. 'Cheungsam' in Andong, Republic of Korea. The strain DM2-R-LB4^T grew at temperatures of 15-45 °C (optimum, 30-37 °C), pH of 5.5-9 (optimum, 8.0), and 0-2 % (w/v) NaCl concentration (optimum, 0%). Phylogenetic analyses based on the 16S rRNA gene sequences revealed that strain DM2-R-LB4^T is related to species of the genus Sphingomonas, and shared 97.8 and 97.5% similarity to Sphingomonas kyenggiensis KCTC 42244^T and Sphingomonas leidyi DSM 4733^T, respectively. The DNA G+C content was 67.9 mol% and genome analysis of the strain DM2-R-LB4^T revealed that the genome size was 4 386 171 bp and contained 4 009 predicted protein-coding genes. The average nucleotide identity (ANI) values between strain DM2-R-LB4^T and S. kyenggiensis KCTC 42244^T, and S. leidyi DSM 4733^T was 76.8 and 76.7 %, respectively, while the values of digital DNA-DNA hybridization (dDDH) were 20.7 and 20.6 %, respectively. C_14 : 0 2-OH, C_16 : 0, and summed feature 8 (C_18 : 1 ω6c and/or C_18 : 1 ω7c) were the major fatty acids (>10 %) in the strain DM2-R-LB4^T. The polar lipids comprised diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylcholine (PC), sphingoglycolipid (SGL), glycolipid (GL), phospholipid (PL), and two unidentified polar lipids (L1 and L2). Ubiquinone-10 (Q-10) was the only respiratory quinone. The polyamine pattern was found to contain homospermidine, putrescine, and spermidine. The results of phylogenetic anlayses, polyphasic studies, revealed that strain DM2-R-LB4^T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas cannabina sp. nov., is proposed. The type strain is DM2-R-LB4^T (=KCTC 92075^T = GDMCC 1.3018^T).

Sphingomonas ginkgonis sp. nov., isolated from phyllosphere of Ginkgo biloba

Strain HMF7854^T, isolated from a ginkgo tree, was an orange-pigmented, Gram-stain-negative, motile by means of a single flagellum, strictly aerobic, rod-shaped bacterium. The isolate grew optimally on Reasoner's 2A agar at 30 °C, pH 7.0-8.0 and 0 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain HMF7854^T belonged to the genus Sphingomonas and was most closely related to Sphingomonasagri HKS-06^T (96.8 % sequence similarity). The major fatty acids were C_17 : 1 ω6c, summed feature 8 (C_18 : 1ω7c and/or C_18 : 1ω6c), summed feature 3 (C_16 : 1ω7c and/or C_16 : 1ω6c) and C_16 : 0. The predominant isoprenoid quinone was ubiquinone-10. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, sphingoglycolipid, two unidentified lipids and two unidentified glycolipids. The genomic DNA G+C content was 68.4 mol%. Thus, based on its phylogenetic, phenotypic and chemotaxonomic data, strain HMF7854^T represents a novel species of the genus Sphingomonas, for which the name Sphingomonasginkgonis sp. nov. is proposed. The type strain of the species is strain HMF7854^T (=KCTC 62461^T=NBRC 113337^T).

First description of bacterial and fungal communities in Colombian coffee beans fermentation analysed using Illumina-based amplicon sequencing

In Colombia, coffee growers use a traditional method of fermentation to remove the cherry pulp surrounding the beans. This process has a great influence on sensory quality and prestige of Colombian coffee in international markets, but has never been studied. Here we use an Illumina-based amplicon sequencing to investigate bacterial and fungal communities associated with spontaneous coffee-bean fermentation in Colombia. Microbial-derived metabolites were further analysed by high-performance liquid chromatography and gas chromatography-mass spectrometry. Highly diverse bacterial groups, comprising 160 genera belonging to 10 phyla, were found. Lactic acid bacteria (LAB), mainly represented by the genera Leuconostoc and Lactobacillus, showed relative prevalence over 60% at all sampling times. The structure of the fungal community was more homogeneous, with Pichia nakasei dominating throughout the fermentation process. Lactic acid and acetaldehyde were the major end-metabolites produced by LAB and Pichia, respectively. In addition, 20 volatile compounds were produced, comprising alcohols, organic acids, aldehydes, esters, terpenes, phenols, and hydrocarbons. Interestingly, 56 microbial genera, associated with native soil, seawater, plants, insects, and human contact, were detected for the first time in coffee fermentation. These microbial groups harbour a remarkable phenotypic diversity and may impart flavours that yield clues to the terroir of Colombian coffees.

Sphingomonas olei sp. nov., with the ability to degrade aliphatic hydrocarbons, isolated from oil-contaminated soil

A yellow-coloured, Gram-stain-negative, non-motile, rod-shaped bacterium, designated K-1-16T, that is capable of degrading aliphatic hydrocarbons was isolated from oil-contaminated soil at Biratnagar, Morang, Nepal. It was able to grow at 15-45 °C, at pH 5.5-9.5 and with 0-5 % (w/v) NaCl. This strain was taxonomically characterized by a polyphasic approach. Based on 16S rRNA gene sequence analysis, strain K-1-16T belongs to the genus Sphingomonas and is closely related to Sphingomonas mucosissima CP173-2T (98.6 % similarity), Sphingomonas dokdonensis DS-4T (97.9 %), Sphingomonas faeni MA-olkiT (97.9 %), Sphingomonas aurantiaca MA101bT (97.8 %) and Sphingomonas xinjiangensis 10-1-84T (96.6 %). The predominant respiratory quinone was ubiquinone Q-10 and the major polyamine was homospermidine. The polar lipid profile revealed the presence of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, phosphatidyldimethylethanolamine and sphingoglycolipid. The predominant fatty acids of strain K-1-16T were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C18 : 1ω7c 11-methyl and C14 : 0 2-OH. The genomic DNA G+C content was 64.8 mol%. Levels of DNA-DNA relatedness between strain K-1-16T and S. mucosissima DSM 17494T, S. dokdonensis KACC 17420T, S. faeni KCCM 41909T and S. aurantiaca KCCM 41908T were 49.7, 41.3, 43.7 and 36.7 %, respectively. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished this strain from its closest phylogenetic neighbours. Thus, strain K-1-16T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas olei sp. nov. is proposed. The type strain is K-1-16T (=KEMB 9005-450T=KACC 19002T=JCM 31674T).

Sphingomonas panaciterrae sp. nov., a plant growth-promoting bacterium isolated from soil of a ginseng field

Strain DCY91(T), a Gram-stain-negative, rod-shaped, aerobic, non-motile bacterium, was isolated from soil of ginseng field in Gyeonggi province, South Korea. Strain DCY91(T) shared the highest 16S rRNA gene sequence similarity with Sphingomonas mucosissima DSM 17494(T) (98.55%), Sphingomonas dokdonensis KACC 17420(T) (98.11%) and Sphingomonas xinjiangensis DSM 26736(T) (96.68%). The strain DCY91(T) was found to able to grow best in trypticase soy agar at 28 °C, at pH 7 and at 0.5 % NaCl. Ubiquinone 10 was identified as the isoprenoid quinone. The major polar lipids were identified as sphingoglycolipid, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The major fatty acids of strain DCY91(T) were identified as unsaturated C18:1 ω7c and saturated C16:0. The major polyamine content was sym-homospermidine. The DNA G + C content was determined to be 65.8 mol% (HPLC). After 6 days of incubation, strain DCY91(T) produced 9.64 ± 1.73 and 33.73 ± 4.66 µg/ml indole-3-acetic acid, using media without L-tryptophan and supplemented with L-tryptophan, respectively. Strain DCY91(T) was also weakly solubilized phosphate and produced siderophores. On the basis of the phenotypic characteristics, genotypic analysis and chemotaxonomic characteristics, strain DCY91(T) is considered to represent a novel species of the genus Sphingomonas, for which the name Sphingomonas panaciterrae sp. nov. is proposed. The type strain is DCY91(T) (=KCTC 42346(T) =JCM 30807(T)).

Sphingomonas gei sp. nov., isolated from roots of Geum aleppicum

A yellow-pigmented bacterium, designated strain ZFGT-11(T), was isolated from roots of Geum aleppicum Jacq. collected from Taibai Mountain in Shaanxi Province, north-west China, and was subjected to a taxonomic study by using a polyphasic approach. Cells of strain ZFGT-11(T) were Gram-stain-negative, strictly aerobic rods that were surrounded by a thick capsule and were motile by means of a single polar flagellum. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain ZFGT-11(T) was a member of the genus Sphingomonas and was closely related to Sphingomonas naasensis KACC 16534(T) (97.6% similarity), Sphingomonas kyeonggiense JCM 18825(T) (96.8%), Sphingomonas asaccharolytica IFO 15499(T) (96.7%) and Sphingomonas leidyi DSM 4733(T) (96.6%). The predominant respiratory quinone was ubiquinone-10 (Q-10) and the major cellular fatty acids were summed feature 8 (comprising C(18 : 1)ω7c and/or C(18 : 1)ω6c), C(17 : 1)ω6c, C(14 : 0) 2-OH, C(16 : 0) and C(15 : 0) 2-OH. The major polyamine of strain ZFGT-11(T) was sym-homospermidine. Phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylcholine, sphingoglycolipid, two unidentified aminoglycolipids, two unidentified phospholipids and two unidentified lipids were detected in the polar lipid profile. The DNA G+C content was 66.8 mol%. DNA-DNA relatedness for strain ZFGT-11(T) with respect to its closest phylogenetic relative S. naasensis KACC 16534(T) was 26.2±4.8% (mean±SD). On the basis of data from the present polyphasic taxonomic study, strain ZFGT-11(T) is considered to represent a novel species of the genus Sphingomonas , for which the name Sphingomonas gei sp. nov. is proposed. The type strain is ZFGT-11(T) ( = CCTCC AB 2013306(T) = KCTC 32449(T) = LMG 27608(T)).

Polymorphobacter multimanifer gen. nov., sp. nov., a polymorphic bacterium isolated from Antarctic white rock

A Gram-stain-negative, non-spore-forming, aerobic, oligotrophic bacterium (strain 262-7(T)) was isolated from a crack of white rock collected in the Skallen region of Antarctica. Strain 262-7(T) grew at temperatures between -4 and 30 °C, with optimal growth at 25 °C. The pH range for growth was between pH 6.0 and 9.0, with optimal growth at approximately pH 7.0. The NaCl concentration range allowing growth was between 0.0 and 1.0%, with an optimum of 0.5%. Strain 262-7(T) showed an unprecedented range of morphological diversity in response to growth conditions. Cells grown in liquid medium were circular or ovoid with smooth surfaces in the lag phase. In the exponential phase, ovoid cells with short projections were observed. Cells in the stationary phase possessed long tentacle-like projections intertwined intricately. By contrast, cells grown on agar plate medium or in liquid media containing organic compounds at low concentration exhibited short- and long-rod-shaped morphology. These projections and morphological variations clearly differ from those of previously described bacteria. Ubiquinone 10 was the major respiratory quinone. The major fatty acids were C(17 : 1)ω6c (28.2%), C(16 : 1)ω7c (22.6%), C(18 : 1)ω7c (12.9%) and C(15 : 0) 2-OH (12.3%). The G+C content of genomic DNA was 68.0 mol%. Carotenoids were detected from the cells. Comparative analyses of 16S rRNA gene sequences indicated that strain 262-7(T) belongs to the family Sphingomonadaceae, and that 262-7(T) should be distinguished from known genera in the family Sphingomonadaceae. According to the phylogenetic position, physiological characteristics and unique morphology variations, strain 262-7(T) should be classified as a representative of a novel genus of the family Sphingomonadaceae. Here, a novel genus and species with the name Polymorphobacter multimanifer gen. nov., sp. nov. is proposed (type strain 262-7(T) = JCM 18140(T) = ATCC BAA-2413(T)). The novel species was named after its morphological diversity and formation of unique projections.

Bacterial diversity of surface sand samples from the Gobi and Taklamaken deserts

Arid regions represent nearly 30 % of the Earth's terrestrial surface, but their microbial biodiversity is not yet well characterized. The surface sands of deserts, a subset of arid regions, are generally subjected to large temperature fluctuations plus high UV light exposure and are low in organic matter. We examined surface sand samples from the Taklamaken (China, three samples) and Gobi (Mongolia, two samples) deserts, using pyrosequencing of PCR-amplified 16S V1/V2 rDNA sequences from total extracted DNA in order to gain an assessment of the bacterial population diversity. In total, 4,088 OTUs (using ≥97 % sequence similarity levels), with Chao1 estimates varying from 1,172 to 2,425 OTUs per sample, were discernable. These could be grouped into 102 families belonging to 15 phyla, with OTUs belonging to the Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria phyla being the most abundant. The bacterial population composition was statistically different among the samples, though members from 30 genera were found to be common among the five samples. An increase in phylotype numbers with increasing C/N ratio was noted, suggesting a possible role in the bacterial richness of these desert sand environments. Our results imply an unexpectedly large bacterial diversity residing in the harsh environment of these two Asian deserts, worthy of further investigation.