Ferviditalea candida gen. nov., sp. nov., a novel member of the family Paenibacillaceae isolated from a geothermal area.

OBJECTIVE: The family Paenibacillaceae is linked to the order Caryophanales. Paenibacillaceae members residing in compost or soil play crucial roles in nutrient recycling and breaking down complex organic materials. However, our understanding of Paenibacillaceae remains limited. METHODS: Strain SYSU GA230002T was conclusively identified using a polyphasic taxonomic approach frequently utilized in bacterial systematics. Standard microbiological techniques were employed to characterize the morphology and biochemistry of strain SYSU GA230002T. RESULTS: An anaerobic and gram--negative bacterium, designated SYSU GA230002T, was isolated from geothermally heated soil of Tengchong, Yunnan Province, south-west China. Phylogenetic analyses based on 16S rRNA gene sequences and genomes showed that strain SYSU GA230002T belongs to the family Paenibacillaceae. 16S rRNA gene sequence similarity (<94.0 %), ANI (<71.95 %) and AAI values (<58.67 %) between strain SYSU GA230002T with other members of the family were lower than the threshold values recommended for distinguishing novel species. Growth was observed at 30-45 °C (optimum, 37 °C), pH 7.0-8.0 (optimum, pH 7.5) and in 0-3.0 % (w/v) NaCl concentrations (optimum, 0 %). The major fatty acids detected were anteiso-C15:0, iso-C16:0 and iso-C17:0. The polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unidentified phospholipid, one unidentified aminolipid and two unidentified glycolipids. The respiratory quinone was MK-7. The DNA G + C content of strain SYSU GA230002T was 49.87 %. CONCLUSION: Based on the results of morphological, physiological properties, and chemotaxonomic characteristics, this strain is proposed to represent a new species of a new genus Ferviditalea candida gen. nov., sp. nov. The type strain of the type species is SYSU GA230002T (=KCTC 25726T = GDMCC 1.4160T).

Chelatococcus albus sp. nov., a bacterium isolated from hot spring microbial mat.

A Gram-stain-negative, non-endospore-forming, motile, short rod-shaped strain, designated SYSU G07232T, was isolated from a hot spring microbial mat, sampled from Rehai National Park, Tengchong, Yunnan Province, south-western China. Strain SYSU G07232T grew at 25-50 °C (optimum, 37 °C), at pH 5.5-9.0 (optimum, pH 6.0) and tolerated NaCl concentrations up to 1.0 % (w/v). Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain SYSU G07232T showed closest genetic affinity with Chelatococcus daeguensis K106T. The genomic features and taxonomic status of this strain were determined through whole-genome sequencing and a polyphasic approach. The predominant quinone of this strain was Q-10. Major cellular fatty acids comprised C19 : 0 cyclo ω8c and summed feature 8. The whole-genome length of strain SYSU G07232T was 4.02 Mbp, and the DNA G+C content was 69.26 mol%. The average nucleotide identity (ANIm ≤84.85 % and ANIb ≤76.08  %) and digital DNA-DNA hybridization (≤ 21.9 %) values between strain SYSU G07232T and the reference species were lower than the threshold values recommended for distinguishing novel prokaryotic species. Thus, based on the provided phenotypic, phylogenetic, and genetic data, it is proposed that strain SYSU G07232T (=KCTC 8141T=GDMCC 1.4178T) be designated as representing a novel species within the genus Chelatococcus, named Chelatococcus albus sp. nov.

Video-assisted thoracic surgery drainage is feasible and safe for acute necrotizing mediastinitis: a retrospective cohort study.

Background: Acute necrotizing mediastinitis (ANM) is a severe infection of the mediastinal loose connective tissue. Traditionally, it has been treated with thoracotomy, but video-assisted thoracic surgery (VATS) is been increasingly used in patients with this condition. This study aimed to compare the outcomes of VATS and open thoracotomy in treating ANM. Methods: The medical records of patients with ANM who underwent surgery between March 2012 and April 2021 were retrieved. A retrospective screening was conducted based on clinical characteristics, bacterial pathogens, surgical approach, and outcomes. The patients were divided into a VATS group and an open thoracotomy (Open) group. The patient characteristics and surgical outcomes of the two groups were summarized and compared. Results: A total of 64 cases were enrolled in this study, including 48 in the VATS group (75%) and 16 in the Open group (25%). The most common site of infection was the neck (n=26, 40.6%). Streptococcus constellatus and Acinetobacter baumannii (A. baumannii) were the most frequently found pathogens in secretion culture. In sputum culture, the most common pathogens were Klebsiella pneumonia and A. baumannii. Postoperative outcomes, including blood transfusion (33.3% vs. 43.8%; P=0.45), duration of postoperative drainage {14 [1-47] vs. 17 [4-54] days; P=0.15}, length of antibiotic medication {14.5 [1-54] vs. 18 [4-54] days; P=0.29}, admission to intensive care unit (ICU) (87.5% vs. 75.0%; P=0.43), length of ICU stay {5 [1-58] vs. 8.5 [1-37] days; P=0.20}, postoperative hospital stay {17 [2-61] vs. 21 [5-56] days; P=0.22}, reoperation rate (12.5% vs. 6.25%; P=0.82), and mortality rate (14.6% vs. 12.5%; P>0.99) were comparable between the two groups. Conclusions: ANM treated by both the VATS and open approach had comparable outcomes. Therefore, VATS is a viable option for patients with ANM.

Oceanobacillus saliphilus sp. nov., Isolated from Saline-Alkali Soil in Heilongjiang Province, China.

A novel bacterium, designated strain APA_H-1(4)T, was isolated from the saline-alkaline soil, Zhaodong, Heilongjiang Province, China. Phenotypic and chemotaxonomic analyses, and whole-genome sequencing were used to determine the taxonomic position of the strain. Phylogenetic analysis indicated that the isolate belongs to the genus Oceanobacillus, and showed the highest sequence similarity to O. damuensis KCTC 33146T (98.35%, similarity) and 'O. massiliensis' DSM 24644 (98.32%). The average nucleotide identity values between strain APA_H-1(4)T and other members of the genus Oceanobacillus were lower than 82% recommended for distinguishing novel prokaryotic species. The digital DNA-DNA hybridization values of strain APA_H-1(4)T with O. damuensis KCTC 33146T and 'O. massiliensis' DSM 24644 were 13.60 and 17.60%, respectively. Cells of strain APA_H-1(4)T were Gram-staining positive, motile, aerobic, spore-forming rods (0.5-0.7 × 1.8-2.6 µm) with flagella. The growth was found to occur optimally at 37 °C. The whole-cell hydrolysate contained meso-diaminopimelic acid as the diagnostic cell wall diamino acid. The main detected polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid and an unidentified polar lipid. The predominant respiratory quinone was identified as menaquinone-7 (MK-7). The major cellular fatty acid (>10%) was anteiso-C15:0. The G + C content of the genomic DNA was determined to be 38.4% based on the draft genome sequence. Based on the comparative analysis of polyphasic taxonomic data, strain APA_H-1(4)T represents a novel species of the genus Oceanobacillus, for which the name Oceanobacillus saliphilus sp. nov. is proposed. The type strain is APA_H-1(4)T (=GDMCC 1.2239T = KCTC 43254T).

Thermomonas flagellata sp. nov. and Thermomonas alba sp. nov., two novel members of the phylum Pseudomonadota isolated from hot spring sediments.

Two novel species, designated strains SYSU G04041T and SYSU G04536T, were isolated from hot spring sediments collected in Yunnan, PR China. Phenotypic and chemotaxonomic analyses, and whole-genome sequencing were used to determine the taxonomic positions of the candidate strains. Phylogenetic analysis using 16S rRNA gene sequence indicated that strain SYSU G04041T showed the highest sequence similarity to Thermomonas haemolytica A50-7-3T (97.5 %), and SYSU G04536T showed the highest sequence similarity to Thermomonas hydrothermalis SGM-6T (98.2 %). The strains could be differentiated from other species of the genus Thermomonas by their distinct phenotypic and genotypic characteristics. Cells of strains SYSU G04041T and SYSU G04536T were aerobic, motile and Gram-stain-negative. Growth both occurred optimally at 45 °C and pH 7.0 for SYSU G04041T and SYSU G04536T. In addition, the predominant respiratory quinone in both isolates was ubiquinone Q-8. The major fatty acids (>10 %) of strain SYSU G04041T were C16 : 0, iso-C15 : 0 and iso-C16 : 0, while the major fatty acids (>10 %) of strain SYSU G04536T were iso-C15 : 0 and iso-C16 : 0. The main detected polar lipids in strains SYSU G04041T and SYSU G04536T included phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The G+C contents of the genomic DNA of strains SYSU G04041T and SYSU G04536T based on draft genomic sequences were 72.5 and 68.3 %, respectively. On the basis of phenotypic, genotypic and phylogenetic data, strains SYSU G04041T and SYSU G04536T represent two novel species of the genus Thermomonas, for which the names Thermomonas flagellata sp. nov. and Thermomonas alba sp. nov. are proposed, with the type strains SYSU G04041T (=CGMCC 1.19366T=KCTC 92228T) and SYSU G04536T (=CGMCC 1.19367T=KCTC 82839T), respectively.

Rhodoflexus caldus gen. nov., sp. nov., a new member of the phylum Bacteroidota isolated from a hot spring sediment.

A thermophilic bacterium, designated strain SYSU G04325T, was isolated from a hot spring sediment in Yunnan, China. Polyphasic taxonomic analyses and whole-genome sequencing were used to determine the taxonomic position of the strain. Phylogenetic analysis using 16S rRNA gene sequences indicated that strain SYSU G04325T shows high sequence similarity to Thermoflexibacter ruber NBRC 16677T (86.2%). The strain can be differentiated from other species of the family Thermoflexibacteraceae by its distinct phenotypic and genotypic characteristics. Cells of the strain SYSU G04325T were observed to be aerobic, Gram-stain negative and filamentous. Growth was found to occur optimally at 45 ºC and pH 7.0. In addition, the respiratory quinone was identified as menaquinone-7, while the major fatty acids (> 10%) were identified as iso-C15:0, iso-C17:0 and Summed Feature 9 (iso-C17:1ω9c). The polar lipids detected included phosphatidylethanolamine, three unidentified phospholipids, one unidentified glycolipid, five unidentified aminolipids and four unidentified polar lipids. The G + C content of the genomic DNA was determined to be 47.6% based on the draft genome sequence. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU G04325T is concluded to represent a novel species of a novel genus in the family Thermoflexibacteraceae, for which the name Rhodoflexus caldus gen. nov., sp. nov. is proposed. The type strain of Rhodoflexus caldus is SYSU G04325T (= MCCC 1K06127T = KCTC 82848T).

Roseomonas ponticola sp. nov., a novel bacterium isolated from Pearl River estuary.

A novel species of the genus Roseomonas, designated SYSU M41301T, was isolated from water sample of the Pearl River estuary in Guangdong, China. Polyphasic, taxonomic and phylogenomic analyses were used to determine the taxonomy position of the strain. Phylogenetic analysis using 16S rRNA gene sequence indicated that strain SYSU M41301T showed the highest sequence similarity to Roseomonas stagni KCTC 22213T (97.9 %) and Roseomonas riguiloci KCTC 23339T (96.4 %). The novel species could be differentiated from other species of the genus Roseomonas by its distinct phenotypic and genotypic characteristics. The isolate was Gram-staining-negative, aerobic, short rod-shape, oxidase-positive and non-motile. The predominant respiratory quinone was ubiquinone 8 (Q-8). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, and one unidentified polar lipid. The major fatty acids (>10 % of total) were 11-methyl C18 : 1 ω7c, summed feature 3 (C16 : 1 ω7c and/ or C16 : 1 ω6c) and summed feature 8 (C18:  :1 ω7c and/or C18 : 1 ω6c). The G+C content of the novel isolate based on genomic DNA was 72.0 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU M41301T should be considered to represent a novel species in the genus Roseomonas, for which the name Roseomonas ponticola sp. nov. is proposed with the type strain SYSU M41301T (=KCTC 72726T=CGMCC 1.18613T).

Thermaurantiacus tibetensis gen. nov., sp. nov., a novel moderately thermophilic bacterium isolated from hot spring microbial mat in Tibet.

Two bacterial strains SYSU G02173T and SYSU G03142 were isolated from hot springs in Tibet, China. Based on the results of nearly full-length 16S rRNA gene sequences and phylogenetic analyses, strains SYSU G02173T and SYSU G03142 were assigned to the family Sphingosinicellaceae, and were closest to Sandaracinobacter sibiricus RB16-17 T (96.04% and 96.12% similarity, respectively). Cells of the both new strains were observed to be motile rod-shape, Gram-staining negative. Growth occurred at pH 6-8 (optimal: pH 7.0) and 37-55 °C (optimal: 45 °C) with 0-1.0% (w/v) NaCl in T4 broth. The cells were found to be positive for oxidase and catalase activities. The major respiratory ubiquinone was Q-8. The major fatty acids were identified as summed feature 8 (C18:1 ω7c and/or C18:1 ω6c), C16:0, C14:0 2-OH. The major polar lipids were found to consist of sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified phospholipid, one unidentified glycolipid, three unidentified aminolipids and two unidentified polar lipids. The DNA G + C contents of strains SYSU G02173T and SYSU G03142 were 71.8%. The average nucleotide identity (ANI) value between strain SYSU G02173T and SYSU G03142 was 99.98%. The amino acid identity (AAI) values between them and their closely related species were below 66.14%. The isolates are characterized by aerobic growth, a yellow endocellular pigment and a higher optimum growth temperature. The results showed that strains SYSU G02173T and SYSU G03142 represent a novel species of a novel genus in the family Sphingomonadaceae, and thus the name Thermaurantiacus tibetensis (type strain SYSU G02173T = KCTC 72052 T = CGMCC 1.16680 T) is proposed.

Rhabdaerophilum calidifontis gen. nov., sp. nov., a novel bacterium isolated from a hot spring, and proposal of Rhabdaerophilaceae fam. nov.

A novel thermotolerant bacterial strain was isolated from a hot spring in a Tibetan geothermal field. Phylogenetic analysis of the 16S rRNA gene sequence of the novel strain showed that it belongs to a distinct lineage far from any known taxa. The new isolate shared the highest pairwise sequence identity with Phreatobacter cathodiphilus S-12T (92.8 % similarity) according to the 16S rRNA gene sequences. Cells were Gram-stain-negative, aerobic, rod-shaped and formed white round colonies. The strain grew at the ranges of 28-45 °C (optimum, 37 °C), pH 5.0-7.0 (optimum, pH 6.0) and 0-2 % NaCl. The strain was positive for catalase and oxidase. The major respiratory quinone was ubiquinone Q-10. Polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The major fatty acids were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The DNA G+C content was 68.3 mol%. Based on these distinguishing properties, this strain is proposed to represent a new species of a new genus Rhabdaerophilum calidifontis gen. nov., sp. nov., within a new family Rhabdaerophilaceae fam. nov. The type strain of the type species of Rhabdaerophilum calidifontis is SYSU G02060T (=KCTC 72351T=CGMCC 1.17070T).

Rhodobacter flagellatus sp. nov., a thermophilic bacterium isolated from a hot spring.

A thermophilic bacterium, designated SYSU G03088T, was isolated from Moincer hot spring, Tibet, PR China. Polyphasic taxonomic analyses and whole-genome sequencing were used to determine the taxonomic position and genomic profiles of the strain. Phylogenetic analysis using 16S rRNA gene sequence indicated that SYSU G03088T showed highest sequence similarity to Rhodobacter blasticus CGMCC 1.3365T (96.0 % sequence identity). The strain could be differentiated from most recognized species of the genus Rhodobacter by its slightly purple colony colour, distinct phenotypic characters and low ANI values. Cells were Gram-staining negative, and oval-to-rod shaped. Poly-ß-hydroxybutyrate and vesicular intracytoplasmic membrane structures were formed inside cells. Growth occurred optimally at 45 °C and pH 7.0. Ubiquinone 10 was the only respiratory quinone. The major fatty acids (>10 %) were C18 : 0, C18 : 1ω7c 11-methyl and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The detected polar lipids of SYSU G03088T included diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylmethylethanolamine. The DNA G+C content of SYSU G03088T was 67.7 % (genome). On the basis of the differences in the phenotypic characteristics and phylogenetic analyses, SYSU G03088T is considered to represent a novel species of the genus Rhodobacter, for which the name Rhodobacter flagellatus sp. nov. is proposed. The type strain is SYSU G03088T (=CGMCC 1.16876T=KCTC 72354T).

Rhabdothermincola sediminis gen. nov., sp. nov., a new actinobacterium isolated from hot spring sediment, and emended description of the family Iamiaceae.

One thermophilic bacterium, designated strain SYSU G02662T, was isolated from hot spring sediment sampled in Tibet, PR China. Polyphasic taxonomic analyses and whole-genome sequencing were used to determine the taxonomy position of the strain. Phylogenetic analysis using 16S rRNA gene sequences indicated that strain SYSU G02662T showed the highest sequence similarity to Actinomarinicola tropica SCSIO 58843T (95.1 %). The strain could be differentiated from other species of the family Iamiaceae by its distinct phenotypic and genotypic characteristics. Cells of strain SYSU G02662T were aerobic, Gram-staining-positive and short rodshaped. Growth occurred optimally at 45 °C and pH 7.0. In addition, meso-diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan. The respiratory quinone was MK-9 (H8), while the major fatty acids (>10 %) were C16 : 0, C17 : 0, C18 : 0 and iso-C16 : 0. The detected polar lipids included diphosphatidylglycerol, phosphatidylinositol mannoside and phosphatidylinositol. The G+C content of the genomic DNA was 70.5 % based on the draft genomic sequence. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU G02662T represents a novel species of a novel genus in the family Iamiaceae, for which the name Rhabdothermincola sediminis gen. nov., sp. nov. is proposed. The type strain of the proposed novel species is SYSU G02662T (=CGMCC 4.7688T=KCTC 49500T).