Emergence of rare and low abundant anaerobic gut Firmicutes is associated with a significant downfall of Klebsiella in human colon cancer.

Gut bacterial dysbiosis has been linked to several gastrointestinal diseases, including deadly colorectal cancer (CRC), a leading cause of mortality in cancer patients. However, perturbation in gut bacteriome during colon cancer (CC, devoid of colorectal malignancy) remains poorly explored. Here, 16S rRNA gene amplicon sequencing was carried out for fecal DNA samples targeted to hypervariable V3-V4 region by employing MiSeq platform to explore the gut bacterial community shift in CC patients. While alpha diversity indices predicted high species richness and diversity, beta diversity showed marked gut bacterial compositional dissimilarity in CC versus healthy controls (HC, n = 10 each). We observed a significant (p < 0.05, Wilcoxon Rank-Sum test) emergence of low-abundant anaerobic taxa, including Parvimonas and Peptostreptococcus, in addition to Subdoligranulum, Coprococcus, Holdemanella, Solobacterium, Bilophila, Blautia, Dorea, Moryella and several unidentified taxa, mainly affiliated to Firmicutes, in CC patients. In addition, we also traced the emergence of putative probiotic taxon Slackia, belonging to Actinomycetota, in CC patients. The emergence of anaerobic Firmicutes in CC is accompanied by a significant (p < 0.05) decline in the Klebsiella, as determined through linear discriminant analysis effect size (LEfSe) and heat tree analyses. Shifts in core microbiome and variation in network correlation were also witnessed. Taken together, this study highlighted a significant and consistent emergence of rare anaerobic Firmicutes suggesting possible anaerobiosis driving gut microbial community shift, which could be exploited in designing diagnostic and therapeutic tools targeted to CC.

Novel spore-forming species exhibiting intrinsic resistance to third- and fourth-generation cephalosporins and description of Tigheibacillus jepli gen. nov., sp. nov.

A comprehensive microbial surveillance was conducted at NASA's Mars 2020 spacecraft assembly facility (SAF), where whole-genome sequencing (WGS) of 110 bacterial strains was performed. One isolate, designated 179-BFC-A-HST, exhibited less than 80% average nucleotide identity (ANI) to known species, suggesting a novel organism. This strain demonstrated high-level resistance [minimum inhibitory concentration (MIC) >256 mg/L] to third-generation cephalosporins, including ceftazidime, cefpodoxime, combination ceftazidime/avibactam, and the fourth-generation cephalosporin cefepime. The results of a comparative genomic analysis revealed that 179-BFC-A-HST is most closely related to Virgibacillus halophilus 5B73CT, sharing an ANI of 78.7% and a digital DNA-DNA hybridization (dDDH) value of 23.5%, while their 16S rRNA gene sequences shared 97.7% nucleotide identity. Based on these results and the recent recognition that the genus Virgibacillus is polyphyletic, strain 179-BFC-A-HST is proposed as a novel species of a novel genus, Tigheibacillus jepli gen. nov., sp. nov (type strain 179-BFC-A-HST = DSM 115946T = NRRL B-65666T), and its closest neighbor, V. halophilus, is proposed to be reassigned to this genus as Tigheibacillus halophilus comb. nov. (type strain 5B73CT = DSM 21623T = JCM 21758T = KCTC 13935T). It was also necessary to reclassify its second closest neighbor Virgibacillus soli, as a member of a novel genus Paracerasibacillus, reflecting its phylogenetic position relative to the genus Cerasibacillus, for which we propose Paracerasibacillus soli comb. nov. (type strain CC-YMP-6T = DSM 22952T = CCM 7714T). Within Amphibacillaceae (n = 64), P. soli exhibited 11 antibiotic resistance genes (ARG), while T. jepli encoded for 3, lacking any known ß-lactamases, suggesting resistance from variant penicillin-binding proteins, disrupting cephalosporin efficacy. P. soli was highly resistant to azithromycin (MIC >64 mg/L) yet susceptible to cephalosporins and penicillins. IMPORTANCE: The significance of this research extends to understanding microbial survival and adaptation in oligotrophic environments, such as those found in SAF. Whole-genome sequencing of several strains isolated from Mars 2020 mission assembly cleanroom facilities, including the discovery of the novel species Tigheibacillus jepli, highlights the resilience and antimicrobial resistance (AMR) in clinically relevant antibiotic classes of microbes in nutrient-scarce settings. The study also redefines the taxonomic classifications within the Amphibacillaceae family, aligning genetic identities with phylogenetic data. Investigating ARG and virulence factors (VF) across these strains illuminates the microbial capability for resistance under resource-limited conditions while emphasizing the role of human-associated VF in microbial survival, informing sterilization practices and microbial management in similar oligotrophic settings beyond spacecraft assembly cleanrooms such as pharmaceutical and medical industry cleanrooms.

Neopusillimonas aromaticivorans sp. nov. isolated from poultry manure.

A polyphasic taxonomic approach was used to characterize a novel bacterium, designated strain CC-YST667T, isolated from poultry manure sampled in Taiwan. The cells were observed to be aerobic, motile and non-spore-forming rods, displaying positive reactions for oxidase. Optimal growth of CC-YST667T was observed at 25 °C, pH 8.0 and with 1 % (w/v) NaCl. The polar lipid profile consisted of phosphatidylmonomethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and multiple unidentified polar lipids. The major polyamine was spermidine. The major cellular fatty acids (>5 %) included C16 : 0, C17 : 0cyclo, C19 : 0cyclo ω8c and C14 : 0 3OH/iso-C16 : 1 I. On the basis of the results of analysis of 16S rRNA gene sequences, this isolate showed the closest phylogenetic relationship with 'Neopusillimonas minor' (with 98.2 % similarity) and Paralcaligenes ureilyticus (with 97.3 % similarity) of the family Alcaligenaceae. The draft genome, (3.3 Mb) with a DNA G+C content of 57.2 mol%, harboured various genes involved in the biodegradation of aromatic hydrocarbons. CC-YST667T shared highest orthologous average nucleotide identity (OrthoANI) with the type strains of species of of the genera Neopusillimonas (72.4‒77.9 %, n=2), Pusillimonas (72.8‒73.0 %, n=2) and Pollutimonas (71.7‒73.0 %, n=5). On the basis of its distinct phylogenetic, phenotypic and chemotaxonomic traits together with the results of comparative 16S rRNA gene sequencing, OrthoANI, digital DNA-DNA hybridization (DDH) and the phylogenomic placement, strain CC-YST667T is considered to represent a novel species of the genus Neopusillimonas, for which the name Neopusillimonas aromaticivorans sp. nov. is proposed. The type strain is CC-YST667T (=BCRC 81321T =JCM 34761T).

Dysbiosis of the oral microbiota composition is associated with oral squamous cell carcinoma and the impact of radiotherapy: a pilot study.

Radiotherapy can potentially influence the diversity and composition of the oral microbiome. We performed a study comparing the composition of oral microbiota in patients with oral squamous cell carcinoma (OSCC) before radiotherapy (n = 6), at three months (n = 6), and six months (n = 6) post-radiotherapy, and controls (n = 6). We profiled the oral microbiome by 16S rRNA gene sequencing using Illumina MiSeq. Alpha diversity (Chao1 index) showed significant differences in species richness between healthy controls and OSCC patients (P = 0.014). Conversely, no noteworthy distinctions were observed in the Chao1 index when comparing the pre-and post-radiation periods at both three and six months. The beta diversity of the oral microbiota differed significantly between the controls and OSCC patients (P = 0.014). However, no significant differences were observed in beta diversity between pre- and post-radiation at three months, whereas a significant difference was observed at six months (P = 0.038). Linear Discriminant Analysis Effect Size (LEfSe) demonstrated lower abundance of Corynebacterium, Actinomyces, Veillonella, and Haemophilus, and higher abundance of Selenomonas and Mycoplasma in OSCC patients than in healthy controls. The oral microbiome composition varied among healthy controls, patients with OSCC, and post-radiation therapy patients with OSCC. The observed recovery in the numerical dominance of specific beneficial oral taxa and the reduction in pathogenic bacteria after radiation therapy highlights the need for further investigations into their clinical implications.

Description of Flavobacterium agricola sp. nov., an auxin producing bacterium isolated from paddy field.

An auxin-producing bacterial strain, CC-SYL302T, was isolated from paddy soil in Taiwan and identified using a polyphasic taxonomic approach. The cells were observed to be aerobic, non-motile, non-spore-forming rods, and tested positive for catalase and oxidase. Produced carotenoid but flexirubin-type pigments were absent. Optimal growth of strain CC-SYL302T was observed at 25 °C, pH 7.0, and with 2% (w/v) NaCl present. Based on analysis of 16S rRNA gene sequences, it was determined that strain CC-SYL302T belongs to the genus Flavobacterium of the Flavobacteriaceae family. The closest known relatives of this strain are F. tangerinum YIM 102701-2 T (with 93.3% similarity) and F. cucumis R2A45-3 T (with 93.1% similarity). Digital DNA-DNA hybridization (dDDH) values were calculated to assess the genetic distance between strain CC-SYL302T and its closest relatives, with mean values of 21.3% for F. tangerinum and 20.4% for F. cucumis. Strain CC-SYL302T exhibited the highest orthologous average nucleotide identity (OrthoANI) values with members of the Flavobacterium genus, ranging from 67.2 to 72.1% (n = 22). The dominating cellular fatty acids (> 5%) included iso-C14:0, iso-C15:0, iso-C16:0, iso-C15:0 3-OH, iso-C17:0 3-OH, C16:1 ω6c/C16:1 ω7c and C16:0 10-methyl/iso-C17:1 ω9c. The polar lipid profile consisted of phosphatidylethanolamine, an unidentified aminolipid, an unidentified aminophospholipid, and nine unidentified polar lipids. The genome (2.7 Mb) contained 33.6% GC content, and the major polyamines were putrescine and sym-homospermidine. Strain CC-SYL302T exhibits distinct phylogenetic, phenotypic, and chemotaxonomic characteristics, as well as unique results in comparative analysis of 16S rRNA gene sequence, OrthoANI, dDDH, and phylogenomic placement. Therefore, it is proposed that this strain represents a new species of the Flavobacterium genus, for which the name Flavobacterium agricola sp. nov. is proposed. The type strain is CC-SYL302T (= BCRC 81320 T = JCM 34764 T).

Description of Pseudogemmobacter faecipullorum sp. nov., isolated from poultry manure.

A polyphasic taxonomic approach was used to characterize a novel bacterium, designated strain CC-YST710T, isolated from poultry manure sampled in Taiwan. Cells of strain CC-YST710T were aerobic, Gram-stain-negative, nonmotile, nonspore-forming rods, displaying positive reactions for catalase, and oxidase activities. Strain CC-YST710T was found to grow optimally at 30°C, pH 7.0, and in the presence of 2% (w/v) NaCl. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, four unidentified aminolipids, one unidentified aminophospholipid, and five unidentified lipids. The major polyamine was spermidine. The dominating cellular fatty acids (> 5%) included C16:0, C18:0, and C18:1ω7c/C18:1ω6c. Based on 16S rRNA gene analysis, this isolate showed the closest phylogenetic relationship with 'Pseudogemmobacter humicola' (97.6%), followed by Pseudogemmobacter bohemicus (97.2%) and 'Pseudogemmobacter hezensis' (97.5%). The draft genome (4.3 Mb) had 62.9 mol% G + C content. CC-YST710T can be distinguished from other Pseudogemmobacter species due to the exclusive presence of key genes encoding p-hydroxybenzoate hydroxylase, protocatechuate 3, 4-dioxygenase (α and ß chain), and homogentisate 1, 2-dioxygenase involved in the degradation of phenolic compounds such as p-hydroxybenzoic acid, protocatechuate, and homogentisate, respectively. Orthologous average nucleotide identity (OrthoANI) of the isolate with the type strains of the genera Pseudogemmobacter were 77.6%‒78.0% (n = 3), followed by Tabrizicola (72.3%‒73.7%, n = 5), and Gemmobacter(72.3%‒73.5%, n = 7). Based on its distinct phylogenetic, phenotypic, and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, OrthoANI, digital DDH, and the phylogenomic placement, strain CC-YST710T is considered to represent a novel Pseudogemmobacter species, for which the name Pseudogemmobacter faecipullorum sp. nov. (type strain CC-YST710T = BCRC 81286T = JCM 34182T).

Niabella agricola sp. nov., isolated from paddy soil.

A polyphasic taxonomic approach was used to characterize a Gram-stain-negative, orange-coloured bacterium (designated strain CC-SYL272T) isolated from paddy soil. Cells were observed to be strictly aerobic, non-motile and non-spore-forming rods, exhibiting positive catalase and oxidase. Strain CC-SYL272T was found to grow optimally at 20-40 °C, pH 6.0-8.0 and NaCl 0-2 % (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CC-SYL272T belongs to the genus Niabella, family Chitinophagaceae, and is most closely related to Niabella pedocola (97.8 %) followed by Niabella drilacis (97.2 %) and established a distinct taxonomic lineage associated with these species. The highest orthologous average nucleotide identity (OrthoANI) values were recorded for strain CC-SYL272T versus Niabella species (69.1-83.5 %, n=8). The mean digital DNA-DNA hybridization (dDDH) value obtained for strain CC-SYL272T against N. pedocola was 27.3 %. The polar lipid profile consisted of phosphatidylethanolamine and five unidentified lipids. The major polyamines were putrescine and sym-homospermidine. The dominating cellular fatty acids (>5 %) included iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3OH and C16 : 1 ω6c/C16 : 1 ω7c. The draft genome (6.25 Mb) of strain CC-SYL272T spanned three contigs having 47.1 mol% DNA G+C content, 5087 protein-encoding genes, 10 rRNA genes and 44 tRNA genes. The genome harboured genes involved in the depolymerization of both animal and plant polysaccharides. Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, OrthoANI, dDDH and the phylogenomic placement, strain CC-SYL272T is considered to represent a novel species of the genus Niabella, affiliated to the family Chitinophagaceae, for which the name Niabella agricola sp. nov. is proposed. The type strain is CC-SYL272T (=BCRC 81319T=JCM 34758T).

Agrilactobacillus fermenti sp. nov. isolated from fermented vegetable residue.

A polyphasic taxonomic approach was used to characterize a Gram-stain-positive fermentative bacterium, designated strain CC-MHH1034T, isolated from a fermented vegetable residue. Cells of strain CC-MHH1034T were facultatively anaerobic, non-motile, and non-spore-forming rods, exhibiting positive catalase, oxidase and protease activities. Optimal growth occurred at 30 °Ð¡ and pH 6.0. Strain CC-MHH1034T shared the highest 16S rRNA gene sequence similarities with Agrilactobacillus composti (95.9 %) followed by Agrilactobacillus yilanensis (95.1 %) and established a distinct taxonomic lineage associated with these species. Highest orthologous average nucleotide identity (OrthoANI) values were recorded for strain CC-MHH1034T versus Agrilactobacillus (71.1-71.6 %, n=2) followed by Ligilactobacillus (66.5-66.8 %, n=2), Lactobacillus (64.1-65.8 %, n=4). The mean digital DNA-DNA hybridization (dDDH) value obtained for strain CC-MHH1034T against Agrilactobacillus was 19.2-19.5 % (n=2). The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids, four unidentified glycolipids, four unidentified phospholipids and one unidentified lipid. The major polyamine was sym-homospermidine and meso-diaminopimelic acid was detected as the cell-wall peptidoglycan. The dominating cellular fatty acids (>5 %) included C16 : 0, iso-C15 : 0, anteiso-C15 : 0 and C18 : 1 ω9c. Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, OrthoANI, dDDH, and the phylogenomic placement, strain CC-MHH1034T is considered to represent a novel species of the genus Agrilactobacillus, affiliated to the family Lactobacillaceae, for which the name Agrilactobacillus fermenti sp. nov. is proposed. The type strain is CC-MHH1034T (=BCRC 81220T=JCM 33476T).

Pusillimonas faecipullorum sp. nov., isolated from the poultry manure.

A polyphasic taxonomic approach was used to characterize a novel bacterium, designated strain CC-YST705T, isolated from poultry manure sampled in Taiwan. Cells of strain CC-YST705T were aerobic, Gram-stain-negative, non-motile, non-spore-forming rods, displaying positive reactions for catalase, oxidase and ß-glucosidase. Optimal growth occurred at 30 °C and pH 8. Strain CC-YST705T shared the highest (> 96.0%) pair-wise 16S rRNA gene sequence similarity with Pusillimonas noertemannii (96.7%), followed by Pusillimonas caeni (96.6%), Eoetvoesia caeni (96.1%) and Paracandidimonas soli (96.0%), and formed a distinct phyletic lineage associate with the clade that accommodated Pusillimonas species. The draft genome (3.1 Mb) having 57.4 mol % G + C content contained genes involved in the catabolism of aromatic hydrocarbons. The orthologous average nucleotide identity (OrthoANI) values were 62.8-73.1% (n = 8), 72.6 (n = 1), 71.5% (n = 1) compared within the type strains of the genera Pusillimonas, Eoetvoesia and Paracandidimonas, respectively. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified aminolipid, two unidentified phospholipids and five unidentified lipids. The major polyamine was spermidine. The dominating cellular fatty acids (> 5%) included C12:0, C16:0, C17:0 cyclo, C19:0 cyclo ω8c and 2 C14:0 3OH/iso-C16:1 I. Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, OrthoANI, digital DDH, and the phylogenomic placement, strain CC-YST705T is considered to represent a novel species of the genus Pusillimonas, for which the name Pusillimonas faecipullorum sp. nov. is proposed. The type strain is CC-YST705T (= BCRC 81285 T = JCM 34168 T).

Vineibacter terrae gen. nov., sp. nov., an ammonium-assimilating and nitrate-reducing bacterium isolated from vineyard soil.

A polyphasic taxonomic approach was used to characterize a Gram-stain-negative bacterium, designated strain CC-CFT640T, isolated from vineyard soil sampled in Taiwan. Cells of strain CC-CFT640T were aerobic, non-motile, nitrate-reducing rods. Test results were positive for catalase, oxidase and proteinase activities. Optimal growth occurred at 30 °Ð¡ and pH 7. Strain CC-CFT640T showed highest 16S rRNA gene sequence similarity to members of the genus Enhydrobacter (90.0 %, n=1) followed by Hypericibacter (89.4-90.0 %, n=2), Reyranella (88.8-89.8 %, n=5) and Nitrospirillum (89.2-89.4 %, n=2), and formed a distinct phyletic lineage distantly associated with the clade that predominately accommodated Reynerella species. The DNA G+C composition of the genome (2.1 Mb) was 67.9 mol%. Genes involved in the reduction of nitrate to nitrite, nitric oxide and nitrous oxide were found. In addition, genes encoding dissimilatory nitrate reduction to ammonia, ammonium transport and ammonium assimilation were also detected. Average nucleotide identity values were 73.3 % (n=1), 74.0-74.6 % (n=2), 67.5-68.3 % (n=2) when compared within the type strains of the genera Enhydrobacter, Reyranella and Niveispirillum, respectively. The dominant cellular fatty acids (>5 %) included C16 : 0, iso-C17 : 1 ω10c, C19 : 0 cyclo ω8c, C18 : 1 2-OH and C18 : 1 ω7c/C18 : 1 ω6c. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, three unidentified aminolipids, three unidentified phospholipids and an unidentified aminophospholipid. The major respiratory quinone was ubiquinone 10 and the major polyamine was spermidine. Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequencing, digital DNA-DNA hybridization, average nucleotide identity and phylogenomic placement, strain CC-CFT640T is considered to represent a novel genus and species of the family Rhodospirillaceae, for which the name Vineibacter terrae gen. nov., sp. nov. is proposed. The type strain is CC-CFT640T (=BCRC 81219T=JCM 33507T).

Zeimonas arvi gen. nov., sp. nov., of the family Burkholderiaceae, harboring biphenyl- and phenolic acid-metabolizing genes, isolated from a long-term ecological research field.

A polyphasic taxonomic approach was used to characterize a Gram-stain-negative bacterium, designated strain CC-CFT501T, harboring xenobiotic- and allelochemical-metabolizing genes, isolated from a long-term ecological research field in Taiwan. Cells of strain CC-CFT501T were catalase- and oxidase-positive, non-motile and short rods. Optimal growth occurred at 30 °C, pH 8 and 1% NaCl. Strain CC-CFT501T was found to share high 16S rRNA gene sequence similarity with the members of genera Quisquiliibacterium (94.3%, n = 1), Pandoraea (93.4-94.0%, n = 23) and Paraburkholderia (93.3-94.0%, n = 9), affiliated to the family Burkholderiaceae. Strain CC-CFT501T shared 76.4% orthologous average nucleotide identity (OrthoANI) and 20.9% digital DNA-DNA hybridization (dDDH) values with Quisquiliibacterium transsilvanicum DSM 29781T. Draft genome sequence (3.83 Mb) of strain CC-CFT501T revealed several genes encoding the proteins involved in biphenyl and phenolic acid metabolism. Fatty acid profile contained C16:0, C18:0, C10:0 3-OH, C16:1 ω7c/C16:1 ω6c and C18:1 ω7c/C18:1 ω6c in predominant amounts. The polar lipid profile consisted of phosphatidylethanolamine, thirteen unidentified amino lipids, two unidentified phospholipids and two unidentified glycolipids. The major polyamine was spermidine and ubiquinone Q-8 was the sole respiratory quinone. The DNA G + C content was 70.0 mol%. Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, ANI and dDDH analyses, strain CC-CFT501T is considered to represent a novel genus and species of the family Burkholderiaceae, for which the name Zeimonas arvi gen. nov., sp. nov. is proposed. The type strain of the type species is CC-CFT501T (= BCRC 81218T = JCM 33506T).

Description of Devosia faecipullorum sp. nov., harboring antibiotic- and toxic compound-resistace genes, isolated from poultry manure.

A polyphasic taxonomic approach was used to characterize a Gram-stain-negative bacterium, designated strain CC-YST696T, harbouring antibiotic- and toxic compound-resistace genes, isolated from poultry manure in Taiwan. Cells of CC-YST696T were short rods, motile with polar flagella, catalase- and oxidase-positive. Optimal growth occurred at 30 °Ð¡, pH 9 and with 1 % NaCl. The results of phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by CC-YST696T associated with Devosia chinhatensis (97.9 % sequence identity), Devosia riboflavina (97.3 %) and Devosia indica (97.2 %), and with lower sequence similarity values to other species. Average nucleotide identity (ANI) values were 72.8-80.0 % (n=17) compared within the type strains of species of of the genus Devosia. CC-YST696T contained C16:0, C18:0, C18:1ω7c 11-methyl and C18:1ω6c/ C18:1ω7c as the predominant fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids, three unidentified glycolipids, two unidentified phospholipids and three unidentified lipids. The DNA G+C content was 62.2 mol% and the predominant quinone was ubiquinone Q-10. On the basis of its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence and ANI analyses, strain CC-YST696T is proposed to represent a novel species of the genus Devosia, for which the name Devosia faecipullorum sp. nov. (type strain CC-YST696T=BCRC 81284T=JCM 34167T) is proposed.

Aeromicrobium terrae sp. nov., isolated from a maize field.

A polyphasic taxonomic approach was used to characterize a Gram-stain-positive bacterium, designated strain CC-CFT486T, isolated from soil sampled in a maize field in Taiwan. Cells of strain CC-CFT486T were short rods, motile with polar flagella, catalase-positive and oxidase-positive. Optimal growth occurred at 30 °Ð¡, pH 8 and 1 % NaCl. Phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by strain CC-CFT486T associated with Aeromicrobium panacisoli (97.0 % sequence identity), Aeromicrobium lacus (97.0 %), Aeromicrobium erythreum (96.8 %) and Aeromicrobium alkaliterrae (96.8 %), and lower sequence similarity values to other species. Average nucleotide identity (ANI) values were 70.6-77.8 % (n=11) compared within the type strains of the genus Aeromicrobium. Strain CC-CFT486T contained C16 : 0, C17 : 0, C17 : 1 ω8c and C18 : 1 ω9c as the predominant fatty acids. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, two unidentified aminophospholipids and three unknown phospholipids. The cell wall peptidoglycan of strains CC-CFT486T contained ll-diaminopimelic acid (ll-DAP) and the major polyamine was spermidine. The DNA G+C content was 70.6 mol% and the predominant quinone was menaquinone 9 (MK-9). Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence and ANI analyses, strain CC-CFT486T is proposed to represent a novel Aeromicrobium species, for which the name Aeromicrobium terrae sp. nov. (type strain CC-CFT486T=BCRC 81217T=JCM 33499T).

Cerasibacillus terrae sp. nov., isolated from maize field, and emended description of Cerasibacillus quisquiliarum Nakamura et al. 2004.

A polyphasic taxonomic approach was used to characterize a Gram-stain-positive bacterium, designated strain CC-CFT480T, isolated from soil sampled in a maize field in Taiwan, ROC. Cells of strain CC-CFT480T were rod-shaped, motile with polar flagella, catalase-positive and oxidase-positive. Optimal growth occurred at 30 °Ð¡, pH 8 and 3 % NaCl. Phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by strain CC-CFT480T associated with Cerasibacillus quisquiliarum (97.2 % sequence identity), Virgibacillus soli (95.7 %), Virgibacillus carmonensis (95.4 %) and Virgibacillus byunsanensis (95.2 %), and lower sequence similarity values to other species. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain CC-CFT480T and C. quisquiliarum were 74.2 and 20.1 %, respectively. Strain CC-CFT480T contained iso-C15:0, C16:1 ω7c alcohol and iso-C17:1 ω10c as the predominant fatty acids. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unknown aminophospholipids, one uncharacterized aminophospholipid and two unknown phospholipids. The major polyamine was spermidine. The DNA G+C content was 34.8 mol% and the predominant quinone was menaquinone 7 (MK-7). Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, ANI and dDDH analyses, strain CC-CFT480T is proposed to represent a novel Cerasibacillus species, for which the name Cerasibacillus terrae sp. nov. (type strain CC-CFT480T=BCRC 81216T=JCM 33498T).

Cohnella fermenti sp. nov., isolated from a fermentation process.

A novel Gram-stain-positive, aerobic, motile with peritrichous flagella, rod-shaped bacterium, designated CC-MHH1044T, was isolated from a preserved vegetable sample. A polyphasic taxonomic approach was applied to the isolates in order to clarify its taxonomic position. Growth of the strain CC-MHH1044T occurred at 15-50 °C (optimum, 30 °C), pH 6.0-8.0 (optimum, pH 7.0) and with 0-2.0 % (w/v) NaCl (optimum, 1 %, w/v). The genome of strain CC-MHH1044T consisted of 8.5 Mb and the genomic DNA G+C content was 58.5 mol%. Comparison of the 16S rRNA gene sequences showed that CC-MHH1044T belonged to the genus Cohnella and showed a close relationship with the type strains of Cohnella damuensis (96.2 %) and Cohnella panacarvi (95.9 %), and lower sequence similarity to other species. Average nucleotide identity values calculated from whole-genome sequencing data proved that CC-MHH1044T represents a distinct Cohnella species. The dominant cellular fatty acids (>5 %) included iso-C14 : 0(7.4 %), iso-C15 : 0 (6.4 %), anteiso-C15 : 0(40.3 %), C16 : 0 (6.6 %) and iso-C16 : 0 (27.0 %). The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unidentified aminophospholipids, one unidentified phospholipid and glycolipid. The major polyamine was spermidine. The predominant isoprenoid quinone was menaqinone 7 (MK-7). Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits, together with results of comparative 16S rRNA gene sequence, average nucleotide identity and digital DNA-DNA hybridization analyses, we conclude that strain CC-MHH1044T represents a novel member of the genus Cohnella, for which the name Cohnella fermenti sp. nov. is proposed. The type strain is CC-MHH1044T (=BCRC 81147T=JCM 32834T).

Description of Azoarcus nasutitermitis sp. nov. and Azoarcus rhizosphaerae sp. nov., two nitrogen-fixing species isolated from termite nest and rhizosphere of Ficus religiosa.

A polyphasic taxonomic approach was used to characterise two presumably novel bacteria, designated strains CC-YHH838T and CC-YHH848T isolated from termite nest and rhizosphere of Ficus religiosa, respectively. These two nitrogen-fixing strains were observed to be Gram-staining-negative, aerobic rod, and colonies were yellowish in color. Growth of strains was observed at 20-37 °C, pH 7-8, and in the presence of 1-2% NaCl. Phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by strain CC-YHH838T and CC-YHH848T associated with Thauera hydrothermalis (97.1% sequence identity), and formed a separate branch with Azoarcus indigens (95.4%), Aromatoleum aromaticum (96.2%), and lower sequence similarity to other species. The calculation of OrthoANI values pointed out strains CC-YHH838T and CC-YHH848T gave 78.9% and 79.8% compared to Thauera hydrothermalis, respectively. The major fatty acids (> 5%) were C16:0, C17:0 cyclo, C10:0 3-OH, C16:1ω7c/C16:1ω6c and C18:1ω7c/C18:1ω6c. The polar lipid profile comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and unidentified aminophospholipid and phospholipids; the predominant polyamines were putrescine and spermidine. The predominant respiratory system was ubiquinone (Q-8) and the DNA G + C contents were 61.4 ± 0.1 mol% and 60.2 ± 1.3 mol%, respectively. Based on the phylogenetic and polyphasic comparisons, strains CC-YHH838T and CC-YHH848T are proposed to represent two novel species within the genus Azoarcus in the family Rhodocyclaceae, for which the name Azoarcus nasutitermitis sp. nov. (type strain CC-YHH838T = BCRC 81059T = JCM 32001T) and Azoarcus rhizosphaerae sp. nov. (type strain CC-YHH848T = BCRC 81060T = JCM 32002T) were proposed.

Description of Gemmobacter aestuarii sp. nov., isolated from estuarine surface water and reclassification of Cereibacter changlensis as Gemmobacter changlensis Chen et al. 2013.

A Gram-stain-negative, tyrosine-metabolizing, non-motile, strictly aerobic, non-spore-forming, rod-shaped marine bacterium, designated strain CC-PW-75T, was isolated from the estuarine water off Pintung, Taiwan. Strain CC-PW-75T formed a distinct phyletic lineage associated with Gemmobacter species, sharing the highest 16S rRNA gene sequence similarity with G. megaterium CF17T and G. straminiformis CAM-8T (96.0% each) followed by G. aquatilis IFAM 1031T and G. nectariphilus AST4T (95.8% each). Analysis of the draft genome (3.76 Mbp) revealed the presence of genes encoding light-harvesting complexes, photosynthetic reaction centers and proteins involved in the metabolism of CO, CO2, HCO3‒ and H2S. However, bacteriochlorophyll a was not detected. Average nucleotide identity values between the genome sequence of CC-PW-75T and the related Gemmobacter species (n = 6) were estimated to be 72.8-76.3%. Polar lipid analysis revealed the presence of phosphatidylglycerol, phosphatidylethanolamine and an unidentified lipid in major amounts, and phosphatidylmonomethylethanolamine, phosphatidylcholine, an unidentified aminolipid and an unidentified lipid in minor amounts. C18:1ω7c and/or C18:1ω6c, C18:0 and C18:1ω7c 11-methyl were identified to be major fatty acids. The DNA G + C content was 66.2 mol% (draft genome sequence). Ubiquinone-10 (Q-10) was the sole respiratory quinone. Based on the polyphasic taxonomic evidence, CC-PW-75T is most likely a novel species of the genus Gemmobacter, affiliated to the family Rhodobacteraceae, for which the name Gemmobacter aestuarii sp. nov. is proposed. The type strain is CC-PW-75T (= JCM 19754T = BCRC 80759T). Also, we propose the reclassification of Cereibacter changlensis as Gemmobacter changlensis Chen et al. 2013 using the polyphasic data presented in this study.

Allorhizobium terrae sp. nov., isolated from paddy soil, and reclassification of Rhizobium oryziradicis (Zhao et al. 2017) as Allorhizobium oryziradicis comb. nov.

A polyphasic taxonomic approach was used to characterize a nitrogen-fixing bacterium, designated strain CC-HIH110T, isolated from paddy soil in Taiwan. Cells of strain CC-HIH110T were Gram-stain-negative, rod-shaped, motile with polar flagella, catalase-positive and oxidase-positive. Optimal growth occurred at 30 °Ð¡, pH 7 and 1 % NaCl. Phylogenetic analyses based on 16S rRNA genes revealed a distinct taxonomic position attained by strain CC-HIH110T associated with Rhizobium oryziradicis (98.4 % sequence identity), Allorhizobium vitis (97.8 %), Allorhizobium taibaishanense (97.7 %) and Allorhizobium undicola (96.0 %), and lower sequence similarity to other species. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain CC-HIH110T and the type strains of other closely related species were 71.5-88.6 % and 19.6-35.5 %, respectively. Strain CC-HIH110T contained C16 : 0 3-OH, C14 : 0 3-OH/iso C16 : 1 I and C18 : 1 ω7c/C18  : 1 ω6c as the predominant fatty acids. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, phosphatidylcholine, three unknown aminophospholipids, two unknown phospholipids and an unknown lipid. The major polyamine was homospermidine. The DNA G+C content was 55.0 mol% and the predominant quinone was ubiquinone (Q-10). Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, ANI and dDDH analyses, strain CC-HIH110T is proposed to represent a novel Allorhizobium species, for which the name Allorhizobium terrae sp. nov. (type strain CC-HIH110T=BCRC 80932T=JCM 31228T). In addition, Rhizobium oryziradicis is reclassified as Allorhizobium oryziradicis (type strain N19T=ACCC 19962T=KCTC 52413T) comb. nov.

Mesorhizobium composti sp. nov., isolated from compost.

A polyphasic taxonomic approach was used to characterize a presumptively novel diazotrophic bacterium, designated strain CC-YTH430T, isolated from a compost sample in Taiwan. Cells of strain CC-YTH430T were found to be Gram-stain negative, facultative anaerobic rods that formed yellow-colored colonies on nutrient agar. Cell growth occurred at 15-40 °C, pH 5.0-9.0 and in the presence of 0-2% NaCl. Strain CC-YTH430T resembled Mesorhizobium species while sharing high pair-wise 16S rRNA gene sequence similarities with Mesorhizobium silamurunense, Mesorhizobium thiogangeticum, Mesorhizobium plurifarium, Mesorhizobium tamadayense, Mesorhizobium amorphae (96.9% each), Mesorhizobium sediminum (96.8%), and Mesorhizobium soli (96.5%) and < 96.5% similarity to other species. Strain CC-YTH430T showed 78.8-79.7% average nucleotide identity compared to the type strains of M. amorphae, M. plurifarium, M. soli, M. tamadayense and M. wenxiniae. The N2-fixing activity of strain CC-YTH430T was 0.2 nmol ethylene h-1 at 30 °C. The respiratory system was ubiquinone 10 (Q-10) and the DNA G+C content was 62.0 ± 0.2 mol%. The major fatty acids (> 5%) were C16:0, C17:0 cyclo, C19:0 cyclo ω8c, C14:0 3OH/C16:1 iso I and C18:1ω7c/C18:1ω6c. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylmonomethylethanolamine and an unidentified aminolipid in major amounts. In addition, phosphatidylethanolamine, an unidentified lipid and several unidentified polar lipids were also found in moderate-to-trace amounts. Based on the phylogenetic, phenotypic and chemotaxonomic features, strain CC-YTH430T is proposed to represent a novel Mesorhizobium species, for which the name Mesorhizobium composti sp. nov. (type strain CC-YTH430T = BCRC 81024T = JCM 31762T) is proposed.

Castellaniella fermenti sp. nov., isolated from a fermented meal.

A polyphasic taxonomic approach was used to characterize a presumably novel bacterium, designated strain CC-YTH191T, isolated from a fermented meal in Taiwan. Cells of strain CC-YTH191T were Gram-stain-negative aerobic rods, which grew at 15-40 °C (optimal 25-30 °C), pH 6.0-9.0 (optimal 7.0) and 1-2 % (w/v) NaCl (optimal 1 %). On the basis of 16S rRNA gene sequence analysis, strain CC-YTH191T appeared to belong to the genus Castellaniella, and was closely related to Castellaniella hirudinis (96.7 % similarity), Castellaniella ginsengisoli (96.7 %) and Castellaniella caeni (96.0 %), while with other related species it shared <96.0 % similarity. The major cellular fatty acids of the isolate were C16 : 0, C17 : 0cyclo, C14 : 0 3OH/C16 : 1iso I and C18 : 1ω7c/C18 : 1ω6c. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylserine, three unidentified phospholipids, an unidentified aminolipid and an unidentified aminophospholpid. Putrescine was the predominant polyamine followed by spermidine. The DNA G+C content was 62.2 mol% and the predominant quinone system was ubiquinone 8 (Q-8). All these features confirmed the placement of the strain CC-YTH191T as a novel species within the genus Castellaniella, for which the name Castellaniella fermenti sp. nov. is proposed. The type strain is CC-YTH191T (=BCRC 81023T=JCM 31755T).