Deciphering the fate of osmotic stress priming on enhanced microorganism acclimation for purified terephthalic acid wastewater treatment with high salinity and organic load.

Osmotic stress priming (OSP) was an effective management strategy for improving microbial acclimation to salt stress. In this study, the interaction between pollutants and microbiota, and microbial osmoregulation were investigated triggered by OSP (alternately increasing salinity and organic loading). Results showed that OSP significantly improved COD removal from 31.53 % to 67.99 % and mitigated the terephthalate inhibition produced by toluate, decreasing from 1908.08 mg/L to 837.16 mg/L compared with direct priming. Due to an increase in salinity, Pelotomaculum and Mesotoga were enriched to facilitate terephthalate degradation and syntrophic acetate oxidation (SAO). And organic load promoted acetate formation through syntrophic metabolism of Syntrophorhabdus/Pelotomaculum and SAO-dependent hydrogenotrophic methanogenesis. K+ absorbing, proline and trehalose synthesis participated in osmoregulation at 0.5 % salinity, while only ectoine alleviated intracellular osmolarity under 1.0 % salinity with OLR of 0.44 kg COD /m3. This study provided in-depth insight for microbial acclimation process of anaerobic priming of saline wastewater.

Temperature-regulated and starvation-induced refractory para-toluic acid anaerobic biotransformation.

Little research was focused on the anerobic degradation of refractory para-toluic acid at present. Thus, temperature-regulated anaerobic system of para-toluic acid fed as sole substrate was built and investigated via microbiota, metabolism intermediates, and function prediction in this study. Results showed that low methane yield was produced in para-toluic acid anaerobic system at alkaline condition. And the causes were owing to anaerobic methane oxidation and potentially H2S production at 37 °C, N2 production by denitrification before starvation and propionic acid occurrence after starvation at 27 °C, and production of N2 and free ammonia, and accumulation of acetic acid at 52 °C. Simultaneously, hydrogenotrophic methanogenesis dependent on syntrophic acetate oxidation (SAO) was predominant, facilitating the removal of para-toluic acid at 52 °C. Moreover, the key intermediate changed from phthalic acid of 37 °C and 27 °C before starvation to terephthalic acid of 52 °C. Starvation promoted removal of para-toluic acid through benzoyl-CoA pathway by Syntrophorhabdus, enrichment of syntrophic propionate degraders of Bacteroidetes and Ignavibacteriaceae, and increase of methylotrophic methanogens.

The fate and behavior mechanism of antibiotic resistance genes and microbial communities in anaerobic reactors treating oxytetracycline manufacturing wastewater.

In this study, two parallel-operated expanded granular sludge bed (EGSB) reactors, one used to treat oxytetracycline (OTC) manufacturing wastewater with gradual increase of OTC concentration as experimental reactor and the other fed with the same wastewater without OTC as control reactor, were operated to investigate the behavior of antibiotics resistance genes (ARGs) and mobile genetic elements (MGEs) and their possible relationships with bacterial community among influent, sludge and effluent environments. Though the average absolute abundance of ARGs slightly decreased (0.26 - log), the ARGs' relative abundance normalized to 16S-rRNA gene copy numbers showed a significant upward trend in effluent (2 multiples - increase) and the absolute and relative abundances both extremely increased in anaerobic sludge, indicating that anaerobic treatment process cannot reduce ARGs efficiently, inversely can increase the risk of ARGs through the proliferation of antibiotics resistance bacteria (ARB) under the suppression of OTC. MGEs, bacterial communities and OTC concentration mainly impacted the ARGs profiles, which contributed 88.4% to the variation of ARGs. The differences and correlations of hosts in influent, effluent and sludge were further confirmed by network analysis. Overall, this study enhanced the understanding of the prevalence and transfer of ARGs in OTC production effluents during anaerobic treatment.

Characteristics of microbial community in EGSB system treating with oxytetracycline production wastewater.

In order to realize the efficient and stable operation of anaerobic digestion for oxytetracycline (OTC) production wastewater which contains high concentration refractory organic matters and antibiotic residues, two laboratory-scale EGSB reactors (the experimental reactor and the control reactor) were constructed for pre-treating OTC production wastewater and the complex characteristics and connections among anaerobic fermentative bacteria, methanogens and fungi were analyzed. The experimental reactor gradually increased OTC doses of 0-200 mg/L by four phases compared with the control reactor which was fed without OTC addition during 280 days' operation. The average COD removal efficiency of 91.44% with the average OTC removal efficiency of 27.90% was achieved at OTC concentration of 200 mg/L. The addition of OTC did not affect the preponderant methanogen type, and Methanosaeta, a strict aceticlastic methanogen genus, was dominant both in working and controlling reactors on day 280. Redundancy analysis revealed that OTC and VFAs were the main environmental factors affecting the microbial communities and molecular ecological networks analysis indicated that the key genera principally belonged to Methanosaeta, Proteobacteria and Apiotrichum. Additionally, the fungi genus Apiotrichum might be related to the degradation of complex organic contaminants in OTC production wastewater treatment system.

Pseudonocardia lutea sp. nov., a novel actinobacterium isolated from soil in Chad.

A novel actinomycete, designated strain NEAU-G57T was isolated from a soil sample collected from the bottom of a river in Chad. A polyphasic approach was employed to determine the status of strain NEAU-G57T. Phylogenetic analysis based on its 16S rRNA gene sequence indicated that the organism should be assigned to the genus Pseudonocardia and formed a monophyletic clade with its closest relatives Pseudonocardia yuanmoensis YIM 75926T (98.8 %), Pseudonocardia halophobica DSM 43089T (98.2 %) and Pseudonocardia kujensis A 4038T (97.6 %). Moreover, morphological and chemotaxonomic properties of strain NEAU-G57T also confirmed the affiliation of the isolate to the genus Pseudonocardia. The cell wall contained meso-diaminopimelic acid and whole-cell sugars were glucose, xylose, arabinose and galactose. The predominant menaquinone was MK-8(H4). The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, hydroxyphosphatidylmethylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol mannosides, one unidentified glycolipid and one unidentified lipid. The major fatty acids were C16 : 0 and C16 : 1ω7c. The DNA G+C content was 73.3 mol%. However, the low level of DNA-DNA relatedness and some phenotypic characteristics allowed the isolate to be differentiated from its closely related species. Therefore, it is concluded that strain NEAU-G57T can be classified as representing a novel species of the genus Pseudonocardia, for which the name Pseudonocardia lutea sp. nov. is proposed. The type strain is NEAU-G57T (=JCM 32387T=CGMCC 4.7397T).

Streptomyces urticae sp. nov., isolated from rhizosphere soil of Urtica urens L.

Two novel Gram-stain positive, spore-forming, aerobic actinomycetes, designated NEAU-PCY-1T and NEAU-PCY-2, were isolated from rhizosphere soil of Urtica urens L. collected from Anshan, Liaoning Province, northeast China. The 16S rRNA gene sequence analysis showed that strains NEAU-PCY-1T and NEAU-PCY-2 exhibited 99.8% similarity with each other and are closely related to Streptomyces abietis DSM 42080T (98.2, 98.3%) and Streptomyces fildesensis DSM 41987T (98.0, 98.1%). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the two strains formed a cluster with these two closely related species. Moreover, DNA-DNA hybridization results and some phenotypic, physiological and biochemical properties differentiated the two strains from their close relatives in the genus Streptomyces. Based on a polyphasic taxonomy study, strains NEAU-PCY-1T and NEAU-PCY-2 are considered to represent a novel species of the genus Streptomyces, for which the name Streptomyces urticae sp. nov. is proposed, with NEAU-PCY-1T (= DSM 105115T = CCTCC AA 2017015T) as the type strain.

Streptomyces capitiformicae sp. nov., a novel actinomycete producing angucyclinone antibiotics isolated from the head of Camponotus japonicus Mayr.

A novel actinomycete, designated strain 1H-SSA4T, was isolated from the head of an ant (Camponotus japonicus Mayr) and was found to produce angucyclinone antibiotics. A polyphasic approach was used to determine the taxonomic status of strain 1H-SSA4T. The DNA G+C content of the draft genome sequence, consisting of 11.4 Mbp, was 70.0 mol%. 16S rRNA gene sequence similarity studies showed that strain 1H-SSA4T belongs to the genus Streptomyces with the highest sequence similarity to Streptomyces hygroscopicus subsp. ossamyceticus NBRC 13983T (98.9 %), and phylogenetically clustered with this species, Streptomyces torulosus LMG 20305T (98.8 %), Streptomyces ipomoeae NBRC 13050T (98.5 %) and Streptomyces decoyicus NRRL 2666T (98.4 %). The morphological and chemotaxonomic properties of the strain were also consistent with those members of the genus Streptomyces. A combination of DNA-DNA hybridization experiments and phenotypic tests were carried out between strain 1H-SSA4T and the above-mentioned strains, which further clarified their relatedness and demonstrated that strain 1H-SSA4T could be distinguished from these strains. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces capitiformicae sp. nov. is proposed. The type strain is 1H-SSA4T (=CGMCC 4.7403T=DSM 104537T).

Longispora urticae sp. nov., isolated from rhizosphere soil of Urtica urens L., and emended descriptions of the species Longisporaalbida and Longisporafulva.

Two Gram-stain-positive, aerobic actinomycete strains, designated NEAU-PCY-3T and NEAU-PCY-4, were isolated from rhizosphere soil of Urtica urens L. collected from Anshan, Liaoning Province, northeast PR China. The 16S rRNA gene sequence analysis showed that the two strains exhibited 99.9 % 16S rRNA gene sequence similarity with each other and that they were most closely to Longispora fulva DSM 45356T (98.7, 98.9 %) and Longispora albida JCM 11711T (97.1, 97.2 %). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the two strains were located in the same lineage and formed a cluster with the genus Longispora. Both strains were observed to contain MK-10(H4) and MK-10(H6) as the predominant menaquinones. The cell wall peptidoglycan was found to contain meso-diaminopimelic acid, d-glutamic acid, glycine and l-alanine. Whole-cell hydrolysates mainly contained galactose, ribose and xylose. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, several glycolipids and several unknown lipids. The major cellular fatty acids for strain NEAU-PCY-3T were iso-C16 : 0, iso-C17 : 0, anteiso-C17 : 0 and C18 : 1ω5c. The DNA-DNA hybridization value between strains NEAU-PCY-3T and NEAU-PCY-4 was 83.6±0.4 %, and the values between the two strains and their closest phylogenetic relatives, belonging to the genus Longispora, were well below 70 %, supporting that they represented a distinct genomic species. An array of phenotypic characteristics also differentiated the strains from their closely related species, the only two validly published Longispora species. On the basis of the genetic, chemotaxonomic and phenotypic properties, strains NEAU-PCY-3T and NEAU-PCY-4 were classified as representatives of a novel species of the genus Longispora, for which the name Longispora urticae sp. nov. is proposed. The type strain is NEAU-PCY-3T (=DSM 105119T=CCTCC AA 2017017T).

Two new species of the genus Streptomyces: Streptomyces camponoti sp. nov. and Streptomyces cuticulae sp. nov. isolated from the cuticle of Camponotus japonicus Mayr.

Two novel actinomycetes, designated strains 2C-SSA16(2)T and 1C-GS8T, were isolated from the cuticle of Camponotus japonicus Mayr, collected from Northeast Agricultural University, Heilongjiang Province, north China. Both of them contained genes (involved in antibiotics biosynthesis) of the ketosynthase (KS) and methyl malonyl transferase domains (PKS-I) and the adenylation domain (NRPS). A polyphasic study was carried out to establish the taxonomic positions of these strains. The 16S rRNA gene sequence analysis showed that the two novel isolates 2C-SSA16(2)T and 1C-GS8T exhibited 98.8% similarity with each other and that they are most closely related to Streptomyces umbrinus JCM 4521T (99.0, 98.6%), Streptomyces ederensis JCM 4958T (98.9, 98.7%), Streptomyces aurantiacus JCM 4453T (98.6, 98.2%), Streptomyces glomeroaurantiacus JCM 4677T (98.6, 98.1%), Streptomyces tauricus JCM4837T (98.2, 98.0%) and Streptomyces phaeochromogenes JCM 4070T (98.2, 99.2%). The corresponding phylogenetic analysis based on partial gyrB gene sequences showed that strains 2C-SSA16(2)T and 1C-GS8T formed a cluster with the above-mentioned strains. The DNA-DNA hybridization data and phenotypic characteristics indicated that strains 2C-SSA16(2)T and 1C-GS8T could be readily distinguished from each other and their closest phylogenetic relatives. Therefore, these two strains are suggested to represent two novel species of the genus Streptomyces, for which the names Streptomyces camponoti sp. nov. and Streptomyces cuticulae sp. nov. are proposed. The type strains are 2C-SSA16(2)T (=CGMCC 4.7276T = DSM 100522T) and 1C-GS8T (=CGMCC 4.7348 = DSM 103127T), respectively.

Streptosporangium jiaoheense sp. nov. and Streptosporangium taraxaci sp. nov., actinobacteria isolated from soil and dandelion root (Taraxacum mongolicum Hand.-Mazz.).

Two novel actinobacteria, designated strains NEAU-Jh1-4T and NEAU-Wp2-0T, were isolated from muddy soil collected from a riverbank in Jiaohe and a dandelion root collected from Harbin, respectively. A polyphasic study was carried out to establish the taxonomic positions of these two strains. The phylogenetic analysis based on the 16S rRNA gene sequences of strains NEAU-Jh1-4T and NEAU-Wp2-0T indicated that strain NEAU-Jh1-4T clustered with Streptosporangium nanhuense NEAU-NH11T (99.32 % 16S rRNA gene sequence similarity), Streptosporangium purpuratum CY-15110T (98.30 %) and Streptosporangium yunnanense CY-11007T (97.95 %) and strain NEAU-Wp2-0T clustered with 'Streptosporangium sonchi ' NEAU-QS7 (99.39 %), 'Streptosporangium kronopolitis' NEAU-ML10 (99.26 %), 'Streptosporangium shengliense' NEAU-GH7 (98.85 %) and Streptosporangium longisporum DSM 43180T (98.69 %). Moreover, morphological and chemotaxonomic properties of the two isolates also confirmed their affiliation to the genus Streptosporangium. However, the low level of DNA-DNA hybridization and some phenotypic characteristics allowed the isolates to be differentiated from the most closely related species. Therefore, it is proposed that strains NEAU-Jh1-4T and NEAU-Wp2-0T represent two novel species of the genus Streptosporangium, for which the name Streptosporangium jiaoheense sp. nov. and Streptosporangium taraxaci sp. nov. are proposed. The type strains are NEAU-Jh1-4T (=CGMCC 4.7213T=JCM 30348T) and NEAU-Wp2-0T (=CGMCC 4.7217T=JCM 30349T), respectively.

Actinocorallia lasiicapitis sp. nov., an actinomycete isolated from the head of an ant (Lasius fuliginosus L.).

A novel actinomycete, designated strain 3H-GS17T, was isolated from the head of an ant (Lasius fuliginosus L.) and characterized using a polyphasic approach. 16S rRNA gene sequence similarity studies showed that strain 3H-GS17T belongs to the genus Actinocorallia with high sequence similarity to Actinocorallia glomerata JCM 9376T (98.13 %) and Actinocorallia longicatena JCM 9377T (97.64 %). The chemotaxonomic properties of strain 3H-GS17T were also consistent with those of members of the genus Actinocorallia. The cell wall contained meso-diaminopimelic acid and whole-cell sugars were ribose, mannose, glucose, galactose and madurose. The predominant menaquinones were MK-9(H4), MK-9(H6) and MK-9(H8). The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The major fatty acids were C16 : 0 and C18 : 1ω7с. A combination of DNA-DNA hybridization experiments and phenotypic tests were carried out between strain 3H-GS17T and its closely related strains, which further clarified their relatedness and demonstrated that 3H-GS17T could be distinguished from these strains. Therefore, strain 3H-GS17T is concluded to represent a novel species of the genus Actinocorallia, for which the name Actinocorallia lasiicapitis sp. nov. is proposed. The type strain is 3H-GS17T (=DSM 100595T=CGMCC 4.7282T).

Streptomyces formicae sp. nov., a novel actinomycete isolated from the head of Camponotus japonicus Mayr.

During a screening for novel and biotechnologically useful actinobacteria in insects, a novel actinomycete with antifungal activity, designated strain 1H-GS9(T), was isolated from the head of a Camponotus japonicus Mayr ant, which were collected from Northeast Agricultural University (Harbin, Heilongjiang, China). Strain 1H-GS9(T) was characterised using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of members of the genus Streptomyces. 16S rRNA gene sequence similarity studies showed that strain 1H-GS9(T) belongs to the genus Streptomyces with high sequence similarities to Streptomyces scopuliridis DSM 41917(T) (98.8 %) and Streptomyces mauvecolor JCM 5002(T) (98.6 %). However, phylogenetic analysis based on the 16S rRNA gene sequence indicated that it forms a monophyletic clade with Streptomyces kurssanovii JCM 4388(T) (98.6 %), Streptomyces xantholiticus JCM 4282(T) (98.6 %) and Streptomyces peucetius JCM 9920(T) (98.5 %). Thus, a combination of DNA-DNA hybridization experiments and phenotypic tests were carried out between strain 1H-GS9(T) and the above-mentioned five strains, which further clarified their relatedness and demonstrated that strain 1H-GS9(T) could be distinguished from these strains. Therefore, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces formicae sp. nov. is proposed. The type strain is 1H-GS9(T) (=CGMCC 4.7277(T) = DSM 100524(T)).