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A Gram-positive, smooth, sub-transparent, faint yellow,0.5–0.7 µm diameter, rod shaped aerobic or facultative aerobic strain P40-2Twas isolated from livestock farms in Northeast China. Strain P40-2T grew at 25–40 °C (optimum 30–38 °C), and in 0–4% (w/v) NaCl (optimum 0%) in LB medium. Based on 16S rRNA gene sequence analysis, strain P40-2T belongs...
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... Using an API 50 CH strip, a positive result was shown for L-arabinose, D-xylose, methylxyloside, galactose, D-glucose, D-fructose, D-mannose, mannitol, methyl-D-mannoside, N-acetyl-glucosamine, amygdalin, arbutin, esculin, salicin, cellobiose, maltose, sucrose, trehalose, gentibiose, turanose, gluconate, erythritol, rhamnose, dulcitol, sorbitol, methyl-D-glucoside, lactose, D-raffinose, xylitol, lysose, tagatose, and 5-ketogluconate. These results were compared with those of Cellulomonas pakistanensis DSM 24792, Cellulomonas hominis DSM 9581, Cellulomonas flavigena JCM 18109 (Ahmed et al. 2014), and Cellulomonas taurus strain P40-2 (Zhang et al. 2021) (Table 1). The most abundant fatty acid for the Marseille-Q7820 strain was 12-methyl-tetradecanoic acid (41.8%), followed by hexadecanoic acid (29.3%) and 14-methyl-hexadecanoic acid (6%). ...
An isolate of a bacterium recovered from an endometrial biopsy failed to be identified by MALDI-TOF mass spectrometry and was subjected to 16S rRNA sequencing. The obtained sequence was compared by BLASTn against the NCBI database, which revealed that the most closely related species was Cellulomonas hominis and Cellulomonas pakistanensis, with 98.85% and 98.45% identity, respectively. Phenotypic characterisation and genome sequencing were performed. The isolate was facultative anaerobic, gram-positive, motile, non-spore forming, and rod-shaped. Cell wall fatty acid profiling revealed that 12-methyl-tetradecanoic acid was the most abundant fatty acid (36%). The genome size was 4.25 Mbp with a G + C content of 74.8 mol%. Genomic comparison of species closely related to this strain showed that all digital DNA–DNA hybridisation (dDDH) and mean orthologous nucleotide identity (OrthoANI) values were below published species thresholds (70% and 95–96%, respectively). Based on these data, we conclude that this isolate represents a new bacterial species belonging to the family Cellulomonadaceae and the phylum Actinomycetota. We propose the name Cellulomonas endometrii sp. nov. The type strain is Marseille-Q7820T (= CSUR Q7820 = CECT 30716).
... Therefore, the research on the application of bioflocculant in microalgae concentration has attracted more and more interests (Bukhari et al. 2020;Lei et al. 2015;Li et al. 2016b;Liu et al. 2015aLiu et al. , 2017aNdikubwimana et al. 2016;Sarang and Nerurkar 2020;Sivasankar et al. 2020;Sun et al. 2015a, b;Wan et al. 2013;Wang et al. 2015;Xu et al. 2018b;Zou et al. 2018). With the increasing attention to environmental protection and safety, microbial flocculants have been used in many industrial fields, such as wastewater treatment (Agunbiade et al. 2017;Chaisorn et al. 2016;Guo et al. 2013;Liu et al. 2016bLiu et al. , 2019Liu et al. , 2020Luo et al. 2014Luo et al. , 2016Ma et al. 2020;Pu et al. 2014Pu et al. , 2018Sajayan et al. 2017;Zhang et al. 2021;Zhong et al. 2020), nanoparticle synthesis (Dlamini et al. , 2020Manivasagan et al. 2015;Muthulakshmi et al. 2017Muthulakshmi et al. , 2019Rasulov et al. 2016a, b;Sathiyanarayanan et al. 2013;Zaki et al. 2014), heavy metal ion adsorption (Agunbiade et al. 2019;Ayangbenro et al. 2019;Cao et al. 2015;Chen et al. 2016;Feng et al. 2013;Gomaa 2012;Guo 2015;Guo and Chen 2017a;Guo and Yu 2014;Huang et al. 2019;Li et al. 2016a;Pathak et al. 2017;Pu et al. 2020;Subudhi et al. 2016;Vimala et al. 2020;Yan et al. 2020), activated sludge dewatering (Guo and Ma 2015;Guo et al. 2015b, d;Liu et al. 2014;Yang et al. 2012Yang et al. , 2017, dye decolorization Xia et al. 2018), pathogen removal from water , and membrane fouling reduction (Deng et al. 2015). Therefore, microbial flocculants gradually replace the traditional inorganic and organic polymeric flocculants which will become an inevitable trend. ...
Microbial flocculants are macromolecular substances produced by microorganisms. Due to its non-toxic, harmless, and biodegradable advantages, microbial flocculants have been widely used in various industrial fields, such as wastewater treatment, microalgae harvest, activated sludge dewatering, heavy metal ion adsorption, and nanoparticle synthesis, especially in the post-treatment process of fermentation with high safety requirement. However, compared with the traditional inorganic flocculants and organic polymeric flocculants, the high production cost is the main bottleneck that restricts the large-scale production and application of microbial flocculants. To reduce the production cost of microbial flocculant, a series of efforts have been carried out and some exciting research progresses have been achieved. This paper summarized the research advances in the last decade, including the screening of high-yield strains and the construction of genetically engineered strains, search of cheap alternative medium, the extraction and preservation methods, microbial flocculants production as an incidental product of other biological processes, combined use of traditional flocculant and microbial flocculant, and the production of microbial flocculant promoted by inducer. Moreover, this paper prospects the future research directions to further reduce the production cost of microbial flocculants, thereby promoting the industrial production and large-scale application of microbial flocculants.
Six Gram-stain-positive, aerobic or facultative anaerobic, catalase-positive, urease- and oxidase-negative, rod-shaped bacteria (zg-ZUI157T/zg-ZUI40, zg-ZUI222T/zg-ZUI199 and zg-ZUI188T/ zg-ZUI168) were characterized by a polyphasic approach. Optimal growth of the six strains was observed at pH 7.0 and 28 °C. Phylogenetic analyses based on the 16S rRNA gene and 247 core genes revealed that they belong to genus Cellulomonas. The three type strains have low digital DNA-DNA hybridization (19.3-30.1%) and average nucleotide identity values (78.0-85.5%) with all available genomes in the genus Cellulomonas, and a DNA G+C content range of 73.0-74.6 mol%. The major fatty acids detected in strain pairs zg-ZUI157T/zg-ZUI40 and zg-ZUI 222T/zg-ZUI199 were C16:0, anteiso-C15:0 and anteiso A-C15:1, and C16:0, anteiso-C15:0, anteiso A-C15:1 and anteiso-C17:0 in strain pair zg-ZUI188T/zg-ZUI168. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol mannosides were the major polar lipids detected in the three novel species. MK-9(H4) was the predominant quinone detected in strains zg-ZUI222T (87.4 %) and zg-ZUI188T (91.4 %), and MK-9(H4) (49.1 %) and MK-8 (43.4 %) in strain zg-ZUI157T. The cell-wall sugars detected in the three novel species mainly contained rhamnose. The cell-wall peptidoglycan type of the three novel species was A4β, with an inferred l-Orn-d-Asp interpeptide bridge for strains zg-ZUI157T and zg-ZUI222T, and l-Orn-d-Glu for strain zg-ZUI188T. Based on the results of the phenotypic, phylogenetic, genomic hybridization, average nucleotide identity and chemotaxonomic analyses, the six strains should be classified as belonging to three novel Cellulomonas species, for which the names Cellulomonas dongxiuzhuiae sp. nov. (zg-ZUI157T=GDMCC 1.2559T=KCTC 49678T), Cellulomonas wangleii sp. nov. (zg-ZUI222T=GDMCC 1.2501T=KCTC 49675T) and Cellulomonas fengjieae sp. nov. (zg-ZUI188T=GDMCC 1.2563T=KCTC 49674T) are proposed.
Soil contamination by heavy metals, particularly mercury (Hg), is a problem that can seriously affect the environment, animals, and human health. Hg has the capacity to biomagnify in the food chain. That fact can lead to pathologies, of those which affect the central nervous system being the most severe. It is convenient to know the biological environmental indicators that alert of the effects of Hg contamination as well as the biological mechanisms that can help in its remediation. To contribute to this knowledge, this study conducted comparative analysis by the use of Shotgun metagenomics of the microbial communities in rhizospheric soils and bulk soil of the mining region of Almadén (Ciudad Real, Spain), one of the most affected areas by Hg in the world The sequences obtained was analyzed with MetaPhlAn2 tool and SUPER-FOCUS. The most abundant taxa in the taxonomic analysis in bulk soil were those of Actinobateria and Alphaproteobacteria. On the contrary, in the rhizospheric soil microorganisms belonging to the phylum Proteobacteria were abundant, evidencing that roots have a selective effect on the rhizospheric communities. In order to analyze possible indicators of biological contamination, a functional potential analysis was performed. The results point to a co-selection of the mechanisms of resistance to Hg and the mechanisms of resistance to antibiotics or other toxic compounds in environments contaminated by Hg. Likewise, the finding of antibiotic resistance mechanisms typical of the human clinic, such as resistance to beta-lactams and glycopeptics (vancomycin), suggests that these environments can behave as reservoirs. The sequences involved in Hg resistance (operon mer and efflux pumps) have a similar abundance in both soil types. However, the response to abiotic stress (salinity, desiccation, and contaminants) is more prevalent in rhizospheric soil. Finally, sequences involved in nitrogen fixation and metabolism and plant growth promotion (PGP genes) were identified, with higher relative abundances in rhizospheric soils. These findings can be the starting point for the targeted search for microorganisms suitable for further use in bioremediation processes in Hg-contaminated environments.
