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1.
Environ Sci Pollut Res Int ; 29(28): 42709-42719, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35088261

RESUMO

The objective is to understand the diversity of bacteria-degrading pesticide pollutants in Xinjiang saline-alkali soil environment and resolve the lack of suitable degrading bacteria resources for bioremediation of pesticide pollution in this environment. The soil of long-term continuous cropping cotton fields in Xinjiang was used to culture the degrading bacterial communities under long-term stress of five pesticides, such as beta-cypermethrin. Then, the degradation rate and structural composition of each bacterial communities were analyzed. The soil bacterial diversity in Xinjiang saline-alkali cotton fields was high, from which not only imidacloprid and other commonly and once used pesticide-degrading bacterial communities were enriched but also isoprocarb-degrading bacterial communities, which had never been used, were enriched. After long-term passage, the structural composition of each degrading bacterial communities was stable, and the degradation rates were between 17 and 48%, respectively, in a specific culture period. Each degrading bacterial communities covers many reported pesticide-degrading bacterial genera and contains unique bacterial genera in each 3. These results laid a foundation for studying the metabolic pathway of pesticide pollutants in saline-alkali environment and exploring microbial resources in Xinjiang. Graphical Abstract Variety of pesticide degrading bacteria resources in saline alkali soil of Xinjiang.


Assuntos
Praguicidas , Poluentes do Solo , Álcalis , Bactérias/metabolismo , Biodegradação Ambiental , Praguicidas/metabolismo , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise
2.
J Inflamm (Lond) ; 17: 13, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210738

RESUMO

BACKGROUND: Osteoarthritis (OA) is characterized by inflammation and extracellular matrix (ECM) degradation and is one of the most common chronic degenerative joint diseases that causes pain and disability in adults. Urolithin A (UA) has been widely reported for its anti-inflammatory properties in several chronic diseases. However, the effects of UA on OA remain unclear. The aim of the current study was to investigate the anti-inflammatory effects and mechanism of UA in interleukin-1ß (IL-1ß)-induced chondrocytes. RESULTS: No marked UA cytotoxicity was noted, and UA protected cartilage from damage following IL-1ß stimulation in micromasses. Moreover, UA promoted the expression of anabolic factors including Sox-9, Collagen II, and Aggrecan while inhibiting the expression of catabolic factors such as matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS-4) in rat chondrocytes. Protective effects of UA were also observed in ex vivo organ culture of articular cartilage. Mechanistically, IL-1ß significantly activated and upregulated the expression of p-ERK 1/2, p-JNK, p-P38, and p-P65, while UA protected chondrocytes against IL-1ß-induced injury by activating the mitogen-activated kinase (MAPK)/nuclear factor-κB (NF-κB) signaling pathways. CONCLUSION: Our results provide the evidence that UA could attenuate IL-1ß-induced cell injury in chondrocytes via its anti-inflammatory action. UA may be a promising therapeutic agent in the treatment of OA.

3.
Int J Syst Evol Microbiol ; 70(1): 631-635, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31661043

RESUMO

A Gram-stain-positive, aerobic bacterium, designated CPCC 204705T, was isolated from a desert soil sample, collected from the Badain Jaran desert. Growth of strain CPCC 204705T was observed at pH 6.0-8.0 and 15-37 °C, with optimal growth at 28 °C and pH 7.0. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CPCC 204705T belonged to the genus Cellulomonas, showing the highest similarity (98.54 %) of 16S rRNA gene sequence to Cellulomonas oligotrophica JCM 17534T. The peptidoglycan type was A4ß, containing d-ornithine and d-glutamic acids as diagnostic amino acids. Rhamnose and galactose were detected in the whole-cell hydrolysate as diagnostic sugars. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C15 : 1A, C14 : 0 and C16 : 0. The major menaquinone was MK-9 (H4) and the polar lipid system contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol mannoside, one unidentified lipid, one unidentified aminolipid and two unidentified aminophospholipids. The DNA-DNA hybridization value between strain CPCC 204705T and C. oligotrophica JCM 17534T was 7.1±0.4 %, and the value of average nucleotide identity between these two strains was 79.8 %. The DNA G+C content of strain CPCC 204705T was 75.4 mol%. Based on the results of physiological experiments, chemotaxonomic data, phylogenetic analysis and DNA-DNA hybridization value, strain CPCC 204705T should be classified as a novel Cellulomonas species. The name Cellulomonas telluris sp. nov. is proposed, with strain CPCC 204705T (=DSM 105430T=KCTC 39974T) as the type strain.


Assuntos
Celulase , Cellulomonas/classificação , Clima Desértico , Filogenia , Areia/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Cellulomonas/enzimologia , Cellulomonas/isolamento & purificação , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
4.
Int J Syst Evol Microbiol ; 69(1): 129-133, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30431413

RESUMO

A Gram-stain-negative, motile, rod-shaped bacterium, designated CPCC 100842T, was isolated from a freshwater reservoir in south-west China. The 16S rRNA gene sequence comparison of strain CPCC 100842T with the available sequences in the GenBank database showed that the isolate was closely related to members of the family Comamonadaceae, with the highest similarities to Simplicispira metamorpha DSM 1837T (98.05 %), Simplicispira limi KCTC 12608T (97.86 %), Simplicispira psychrophila LMG 5408T (97.04 %) and Simplicispira piscis JCM 19291T (97.0 %). In the phylogenetic tree based on 16S rRNA gene sequences, strain CPCC 100842T formed a distinct phylogenetic subclade within the genus Simplicispira. The major cellular fatty acids were as C16 : 0 and summed feature 3 (C16 : 1 ω7c/C16 : 1ω6c). Q-8 was detected as the only respiratory quinone. Phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, aminophospholipid and glycolipid were found in the polar lipid extraction. The genomic DNA G+C content was 67.4 mol%. The average nucleotide identity value was 80.4 % by comparing the draft genome sequences of strain CPCC 100842T and S. metamorpha DSM 1837T. The DNA-DNA hybridization result between strain CPCC 100842T and S. metamorpha DSM 1837T showed 37±3 % genomic relatedness. On the basis of the genotypic analysis and phenotypic characteristics, we propose that strain CPCC 100842T represents a novel species of the genus Simplicispira in the family Comamonadaceae with the name Simplicispira lacusdiani sp. nov. Strain CPCC 100842T (=KCTC 52093T=DSM 102231T) is the type strain of the species.


Assuntos
Comamonadaceae/classificação , Água Doce/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Comamonadaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
5.
Antonie Van Leeuwenhoek ; 111(2): 265-273, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28980087

RESUMO

A novel aerobic bacterium, designated strain LAM9153T, was isolated from a saline soil sample collected from Lingxian County, Shandong Province, China. Cells of strain LAM9153T were observed to be Gram-stain negative, non-motile, non-spore-forming and rod-shaped. The new isolate grew optimally at 30-35 °C, pH 7.0 and 0.5% of NaCl concentration (w/v). According to the phylogenetic analysis based on the 16S rRNA gene sequence, strain LAM9153T shares high similarity with Chitinophaga terrae Gsoil 238T (96.9%) and Chitinophaga niabensis JS 13-10T (95.9%), forming a subcluster with C. terrae Gsoil 238T, Chitinophaga cymbidii R156-2T, C. niabensis JS 13-10T and Chitinophaga soli Gsoil 219T in the phylogenetic tree. The major cellular fatty acids (> 10%) were identified as iso-C15:0, iso-C17:0 3-OH and summed features 3 (C16:1 ω6c and/or C16:1 ω7c). The predominant respiratory quinone was identified as menaquinone MK-7. The polar lipids consisted of phosphatidylethanolamine, aminophospholipid, three unidentified aminolipids and five unidentified lipids. The genomic DNA G+C content was determined to be 53.2 ± 1.6 mol%. On the basis of phylogenetic, chemotaxonomic and phenotypic data, strain LAM9153T is concluded to represent a novel species of the genus Chitinophaga, for which the name Chitinophaga salinisoli sp. nov. is proposed. The type strain is LAM9153T (= ACCC 19960T = JCM 30847T).


Assuntos
Bacteroidetes/classificação , Salinidade , Microbiologia do Solo , Solo/química , Bacteroidetes/citologia , Bacteroidetes/isolamento & purificação , Bacteroidetes/fisiologia , Composição de Bases , Metabolômica/métodos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Biotechnol Biofuels ; 10: 236, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29046722

RESUMO

BACKGROUND: Environmental issues, such as the fossil energy crisis, have resulted in increased public attention to use bioethanol as an alternative renewable energy. For ethanol production, water and nutrient consumption has become increasingly important factors being considered by the bioethanol industry as reducing the consumption of these resources would decrease the overall cost of ethanol production. Biogas slurry contains not only large amounts of wastewater, but also the nutrients required for microbial growth, e.g., nitrogen, ammonia, phosphate, and potassium. Therefore, biogas slurry is an attractive potential resource for bioethanol production that could serve as an alternative to process water and nitrogen sources. RESULTS: In this study, we propose a method that replaces the process water and nitrogen sources needed for cellulosic ethanol production by Zymomonas mobilis with biogas slurry. To test the efficacy of these methods, corn straw degradation following pretreatment with diluted NaOH and enzymatic hydrolysis in the absence of fresh water was evaluated. Then, ethanol fermentation using the ethanologenic bacterial strain Z. mobilis ZMT2 was conducted without supplementing with additional nitrogen sources. After pretreatment with 1.34% NaOH (w/v) diluted in 100% biogas slurry and continuous enzymatic hydrolysis for 144 h, 29.19 g/L glucose and 12.76 g/L xylose were generated from 30 g dry corn straw. The maximum ethanol concentration acquired was 13.75 g/L, which was a yield of 72.63% ethanol from the hydrolysate medium. Nearly 94.87% of the ammonia nitrogen was depleted and no nitrate nitrogen remained after ethanol fermentation. The use of biogas slurry as an alternative to process water and nitrogen sources may decrease the cost of cellulosic ethanol production by 10.0-20.0%. By combining pretreatment with NaOH diluted in biogas slurry, enzymatic hydrolysis, and ethanol fermentation, 56.3 kg of ethanol was produced by Z. mobilis ZMT-2 through fermentation of 1000 kg of dried corn straw. CONCLUSIONS: In this study, biogas slurry replaced process water and nitrogen sources during cellulosic ethanol production. The results suggest that biogas slurry is a potential alternative to water when pretreating corn straw and, thus, has important potential applications in cellulosic ethanol production from corn straw. This study not only provides a novel method for utilizing biogas slurry, but also demonstrates a means of reducing the overall cost of cellulosic ethanol.

7.
Antonie Van Leeuwenhoek ; 110(8): 1027-1034, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28456894

RESUMO

A novel facultatively anaerobic bacterium, designated strain LAM-WHM-D11T, was isolated from a frozen soil sample of China. Cells of strain LAM-WHM-D11T were observed to be Gram-stain negative, non-motile and rod-shaped. Colonies were yellowish, and circular with convex shape. Strain LAM-WHM-D11T was found to be able to grow at 4-40 °C (optimum 15 °C), pH 7.5-2.0 (optimum 9.5) and 0-2.5% NaCl (w/v) (optimum 1.5%). The 16S rRNA gene sequence similarity analysis showed that strain LAM-WHM-D11T is closely related to Arenimonas metalli CF5-1T (98.0%), Arenimonas aquaticum NA-09T (97.9%), Arenimonas donghaensis HO3-R19T (95.6%) and Arenimonas aestuarii S2-21T (95.3%). The DNA-DNA hybridization values between the isolate and A. metalli CGMCC 1.10787T, A. aquaticum KACC 14663T, A. donghaensis KACC 11381T were 41.0 ± 1.7, 44.7 ± 1.4 and 42.8 ± 1.2%, respectively. The genomic DNA G+C content was found to be 66.5 mol% as determined by the T m method. The major cellular fatty acids were identified as iso-C15:0 and iso-C16:0. The major isoprenoid quinone was identified as ubiquinone 8 (Q-8). The major polar lipids were found to be diphosphatidyglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmonomethylethanolamine, two phospholipids and five unidentified lipids. Based on the phylogenetic, phenotypic and chemotaxonomic characteristics, strain LAM-WHM-D11T is concluded to represent a novel species within the genus Arenimonas, for which the name Arenimonas alkanexedens sp. nov. is proposed. The type strain is LAM-WHM-D11T (ACCC 19750T = JCM 30464T).


Assuntos
Bactérias/isolamento & purificação , DNA Bacteriano , Bactérias/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Ácidos Graxos , Fosfolipídeos , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Solo , Microbiologia do Solo
8.
Microb Cell Fact ; 15(1): 101, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27287016

RESUMO

BACKGROUND: The cell growth and ethanol yield of Zymomonas mobilis may be detrimentally affected by salt stress frequently present in some biomass-based fermentation systems, leading to a decrease in the rate of sugar conversion to ethanol or other bioproducts. To address this problem, improving the salt tolerance of Z. mobilis is a desirable way. However, limited progress has been made in development of Z. mobilis with higher salt tolerance for some technical challenges in the past decades. Recently, transposon insertion mutant system has been widely used as a novel genetic tool in many organisms to develop mutant strains. In this study, Tn5-based transposon insertion mutagenesis system firstly used for construction of higher salt tolerance strain in Z. mobilis. RESULTS: Approximately 200 Z. mobilis ZM4 mutants were generated by using Tn5-based transposon mutagenesis system. The mutant strain ZMT2 with improved salt tolerance phenotype was obtained by screening on RM agar plates with additional 1 % NaCl. Strain ZMT2 was confirmed to exhibit better fermentation performance under NaCl stress than wild type of strain ZM4. The transposon insertion was located in ZMO1122 (himA) by genome walking. Discruption of himA gene showed that himA may play an important role in response to salt tolerance in Z. mobils. CONCLUSIONS: The mutant strain ZMT2 with a transposon insertion in himA gene of the genome showed obviously higher sugar conversion rate to ethonal under up to 2 % NaCl stress than did the wild ZM4 strain. Besides, ZMT2 exhibited shared fermentative capabilities with wild ZM4 strain under no or low NaCl stress. This report firstly showed that himA played a role in responding to NaCl stress. Furthermore, the result indicated that Tn5-based transposon mutagenesis system was a feasible tool not only for genetic engineering in Z. mobilis strain improvement, but also in tapping resistent genes.


Assuntos
Tolerância ao Sal/genética , Transposases/genética , Zymomonas/genética , Zymomonas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Etanol/metabolismo , Engenharia Genética , Glucose/metabolismo , Mutagênese Insercional , NAD/metabolismo , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Transposases/metabolismo , Zymomonas/crescimento & desenvolvimento
9.
Antonie Van Leeuwenhoek ; 109(5): 721-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26979511

RESUMO

A novel facultatively anaerobic bacterium, designated strain LAM0A28(T), was isolated from a saline silt sample collected from the Chinese Sea of Death located in Suining city, Sichuan province, China. Cells of strain LAM0A28(T) were observed to be Gram-stain positive, motile, endospore-forming and straight-rod shaped. Strain LAM0A28(T) was found to be able to grow at 15-45 °C (optimum: 30-35 °C), pH 5.0-10.0 (optimum: 7.5) and 0-5 % NaCl (w/v) (optimum: 0.5 %). The 16S rRNA gene sequence similarity analysis showed that strain LAM0A28(T) is closely related to Paenibacillus jilunlii DSM 23019(T) (97.5 %) and Paenibacillus graminis DSM 15220(T) (97.2 %). The DNA-DNA hybridization values between the isolate and P. jilunlii DSM 23019(T), P. graminis DSM 15220(T) were 30.2 ± 1.6 % and 44.7 ± 2.1 %, respectively. The DNA G+C content was found to be 51.2 mol% as determined by the T m method. The major cellular fatty acids were identified as anteiso-C15:0, C16:0, iso-C16:0 and C14:0. The major isoprenoid quinone was identified as MK-7. The cell wall peptidoglycan was found to contain meso-diaminopimelic acid. The major polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two aminophospholipids and six unidentified lipids. Based on the phylogenetic, phenotypic and chemotaxonomic characteristics, strain LAM0A28(T) is concluded to represent a novel species within the genus Paenibacillus, for which the name Paenibacillus salinicaeni sp. nov. is proposed. The type strain is LAM0A28(T) (=ACCC 00741(T) = JCM 30850(T)).


Assuntos
Paenibacillus/classificação , Paenibacillus/isolamento & purificação , Água do Mar/microbiologia , Anaerobiose , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , DNA Ribossômico/genética , Paenibacillus/genética , Paenibacillus/fisiologia , Filogenia , Salinidade , Esporos Bacterianos/citologia
10.
J Biotechnol ; 220: 88-9, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26806488

RESUMO

The type strain Lentibacillus amyloliquefaciens LAM0015(T) with considerably highly NaCl tolerance is a member of halophiles. Here we report its genome sequence, the first to publish complete genome sequence of the Lentibacillus genus. It contains 3,858,520bp with an average GC content of 42.12%, encoding multiple valuable proteins academically and industrially. The genome sequence of strain LAM0015(T) provides basic information for further elucidation of halophilic mechanism and wider exploitation of functional genes.


Assuntos
Bacillaceae/genética , Genoma Bacteriano , Bacillaceae/isolamento & purificação , Bacillaceae/fisiologia , Composição de Bases , Sequência de Bases , China , Mapeamento Cromossômico , DNA Bacteriano/genética , Tamanho do Genoma , Microbiologia Industrial , Dados de Sequência Molecular , RNA Bacteriano/genética , Cloreto de Sódio , Microbiologia do Solo
11.
Antonie Van Leeuwenhoek ; 109(2): 171-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26545789

RESUMO

A Gram-stain positive, non-motile, non-sporogenous, aerobic, rod-shaped and halophilic bacterium, designated LAM0015(T), was isolated from a saline sediment sample collected from Yantai City in China. The isolate was found to be able to grow at NaCl concentrations of 5-25 % (w/v) (optimum: 7-12 %), 15-45 °C (optimum: 35 °C) and pH 5.0-9.0 (optimum: 7.0). The major fatty acids were determined to be anteiso-C15:0 and anteiso-C17:0. The predominant respiratory quinone was identified as MK-7. The cell wall peptidoglycan was determined to contain meso-diaminopimelic acid. The polar lipids were found to be diphosphatidyglycerol, phosphatidylglycerol, five phospholipids and one glycolipid. The DNA G+C content was 43.1 mol% as determined by the T m method. Analysis of the 16S rRNA gene sequence indicated that the isolate belongs within the genus Lentibacillus and is closely related to Lentibacillus persicus DSM 22530(T), Lentibacillus salicampi JCM 11462(T) and Lentibacillus jeotgali JCM 15795(T) with 97.3, 96.7 and 96.4 % sequence similarity, respectively. The DNA-DNA hybridization value between LAM0015(T) and L. persicus DSM 22530(T) was 51.2 ± 1.4 %. Based on its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0015(T) is concluded to represent a novel species of the genus Lentibacillus, for which the name Lentibacillus amyloliquefaciens sp. nov. is proposed. The type strain is LAM0015(T) (=ACCC 06401(T) = JCM 19838(T)).


Assuntos
Bacillaceae/isolamento & purificação , Sedimentos Geológicos/microbiologia , Cloreto de Sódio/metabolismo , Bacillaceae/classificação , Bacillaceae/genética , Bacillaceae/metabolismo , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Sedimentos Geológicos/análise , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Cloreto de Sódio/análise
12.
Antonie Van Leeuwenhoek ; 108(3): 659-66, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26133115

RESUMO

A novel aerobic bacterium, designated strain LAM0705(T), was isolated from the rhizosphere of Populus alba in the Peking University Third Hospital. Cells of strain LAM0705(T) were observed to be Gram-stain positive, motile, spore-forming and rod-shaped. The optimal temperature and pH for growth were found to be 30 °C and pH 7.5, respectively. Strain LAM0705(T) was found to be able to grow in the presence 0-5 % NaCl (w/v) (optimum 1.0 %). The major fatty acids of strain LAM0705(T) were identified as anteiso-C15:0, C16:0 and iso-C16:0. The dominant polar lipids were found to consist of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The cell wall peptidoglycan of strain LAM0705(T) was found to contain meso-diaminopimelic acid. The predominant menaquinone was identified as MK-7. The G+C content of genomic DNA was found to be 48 mol% when determined by the T m method. The 16S rRNA gene sequence similarity analysis indicated that strain LAM0705(T) is closely related to Paenibacillus agaridevorans DSM 1355(T) and Paenibacillus thailandensis KCTC 13043(T) with 97.8 and 96.1 % sequence similarity, respectively. The DNA-DNA hybridization value between strain LAM0705(T) and P. agaridevorans DSM 1355(T) was 47 ± 0.8 %. On the basis of its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0705(T) is concluded to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus populi sp. nov. is proposed. The type strain is LAM0705(T) (=ACCC 06427(T) = JCM 19843(T)).


Assuntos
Paenibacillus/classificação , Paenibacillus/isolamento & purificação , Populus , Rizosfera , Microbiologia do Solo , Aerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Concentração de Íons de Hidrogênio , Locomoção , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/fisiologia , Peptidoglicano/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Esporos Bacterianos/citologia , Temperatura , Vitamina K 2/análise
13.
Appl Microbiol Biotechnol ; 99(13): 5739-48, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25935346

RESUMO

Furfural and acetic acid from lignocellulosic hydrolysates are the prevalent inhibitors to Zymomonas mobilis during cellulosic ethanol production. Developing a strain tolerant to furfural or acetic acid inhibitors is difficul by using rational engineering strategies due to poor understanding of their underlying molecular mechanisms. In this study, strategy of adaptive laboratory evolution (ALE) was used for development of a furfural and acetic acid-tolerant strain. After three round evolution, four evolved mutants (ZMA7-2, ZMA7-3, ZMF3-2, and ZMF3-3) that showed higher growth capacity were successfully obtained via ALE method. Based on the results of profiling of cell growth, glucose utilization, ethanol yield, and activity of key enzymes, two desired strains, ZMA7-2 and ZMF3-3, were achieved, which showed higher tolerance under 7 g/l acetic acid and 3 g/l furfural stress condition. Especially, it is the first report of Z. mobilis strain that could tolerate higher furfural. The best strain, Z. mobilis ZMF3-3, has showed 94.84% theoretical ethanol yield under 3-g/l furfural stress condition, and the theoretical ethanol yield of ZM4 is only 9.89%. Our study also demonstrated that ALE method might also be used as a powerful metabolic engineering tool for metabolic engineering in Z. mobilis. Furthermore, the two best strains could be used as novel host for further metabolic engineering in cellulosic ethanol or future biorefinery. Importantly, the two strains may also be used as novel-tolerant model organisms for the genetic mechanism on the "omics" level, which will provide some useful information for inverse metabolic engineering.


Assuntos
Ácido Acético/metabolismo , Adaptação Biológica , Tolerância a Medicamentos , Etanol/metabolismo , Furaldeído/metabolismo , Zymomonas/genética , Zymomonas/metabolismo , Antibacterianos/metabolismo , Lignina/metabolismo , Engenharia Metabólica , Zymomonas/efeitos dos fármacos
14.
Antonie Van Leeuwenhoek ; 107(6): 1429-36, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25896305

RESUMO

A novel facultatively anaerobic bacterial strain, designated LAM0504(T), was isolated from a pit mud of Luzhou flavour liquor alcohol fermentation in Sichuan Province, China. Cells of strain LAM0504(T) were observed to be Gram-stain negative, spore-forming, rod shaped and motile by means of peritrichous flagella. Strain LAM0504(T) was found to be able to grow at 20-48 °C (optimum: 30 °C), pH 5.0-9.0 (optimum: 7.0) and 0-3 % NaCl (w/v) (optimum: 1.0 %). The 16S rRNA gene sequence similarity analysis showed that strain LAM0504(T) was most closely related to Paenibacillus konsisdensis JCM 14798(T), Fontibacillus phaseoli LMG 27589(T) and Paenibacillus motobuensis JCM 12774(T), with 97.0, 96.8 and 96.7 % sequence similarity, respectively. The DNA-DNA hybridization value between strain LAM0504(T) and P. konsisdensis JCM 14798(T) was 53.3 ± 1.2 %. The genomic DNA G+C content of strain LAM0504(T) was 43.0 mol% as determined by the Tm method. The major fatty acids of strain LAM0504(T) were identified as anteiso-C15:0, C16:0 and iso-C15:0. The cell-wall peptidoglycan was found to contain meso-diaminopimelic acid. The predominant menaquinone was identified as MK-7. The major polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, two unidentified glycolipids and three unidentified lipids. On the basis of its physiological and phylogenetic characteristics, strain LAM0504(T) is concluded to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus vini sp. nov. is proposed. The type strain is LAM0504(T) (=ACCC 06420(T) = JCM 19842(T)).


Assuntos
Microbiologia de Alimentos , Paenibacillus/classificação , Paenibacillus/isolamento & purificação , Aerobiose , Álcoois/metabolismo , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Fermentação , Glicolipídeos/análise , Concentração de Íons de Hidrogênio , Locomoção , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/fisiologia , Peptidoglicano/análise , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Temperatura , Vitamina K 2/análise
15.
Appl Microbiol Biotechnol ; 99(12): 5363-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25895089

RESUMO

Furfural from lignocellulosic hydrolysates is the key inhibitor for bio-ethanol fermentation. In this study, we report a strategy of improving the furfural tolerance in Zymomonas mobilis on the transcriptional level by engineering its global transcription sigma factor (σ(70), RpoD) protein. Three furfural tolerance RpoD mutants (ZM4-MF1, ZM4-MF2, and ZM4-MF3) were identified from error-prone PCR libraries. The best furfural-tolerance strain ZM4-MF2 reached to the maximal cell density (OD600) about 2.0 after approximately 30 h, while control strain ZM4-rpoD reached its highest cell density of about 1.3 under the same conditions. ZM4-MF2 also consumed glucose faster and yield higher ethanol; expression levels and key Entner-Doudoroff (ED) pathway enzymatic activities were also compared to control strain under furfural stress condition. Our results suggest that global transcription machinery engineering could potentially be used to improve stress tolerance and ethanol production in Z. mobilis.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Furaldeído/metabolismo , Fator sigma/genética , Fator sigma/metabolismo , Zymomonas/metabolismo , Fermentação , Engenharia Genética , Zymomonas/genética
16.
Int J Syst Evol Microbiol ; 65(11): 3788-3793, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28875926

RESUMO

Four novel bacterial strains belonging to the genus Kurthia were isolated from the surface of a weevil of the family Curculionidae (strain 10y-14T), and from bark samples of hybrid poplar, Populus × euramericana (strains 6-3, 2-5 and 06C10-3-14), in Puyang, Henan Province, China. Phylogenetic analyses of the 16S rRNA gene and multilocus sequence analysis (MLSA) data showed that the four strains form a distinct cluster in the genus Kurthia, indicating that they all belong to a single taxon within the genus. DNA-DNA hybridization levels between strain 10y-4T and Kurthia huakuii LAM0618T and Kurthia massiliensis DSM 24639T were 58.31 and 53.92 %, respectively. This indicates that the four novel strains represent a species distinct from these two closely related species. The DNA G+C content of the novel strains was 42.1-42.6 %. The major fatty acids were iso-C15 : 0 and anteiso-C15 : 0.The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown phospholipid and unidentified aminophospholipids. The predominant menaquinones were MK-7 (90 %) and MK-6 (10 %). The major cell-wall amino acids were lysine, alanine, glutamic acid and glycine. On the basis of the MLSA and 16S rRNA gene sequence phylogenetic analyses, DNA-DNA reassociation values, DNA base composition, and biochemical and phenotypic characteristics, the four strains are considered to represent a novel species within the genus Kurthia, for which the name Kurthia populi sp. nov. is proposed. The type strain is 10y-14T ( = CFCC 11600T = KCTC 33522T).

17.
Biotechnol Biofuels ; 7: 101, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25024744

RESUMO

Biosynthesis of liquid fuels and biomass-based building block chemicals from microorganisms have been regarded as a competitive alternative route to traditional. Zymomonas mobilis possesses a number of desirable characteristics for its special Entner-Doudoroff pathway, which makes it an ideal platform for both metabolic engineering and commercial-scale production of desirable bio-products as the same as Escherichia coli and Saccharomyces cerevisiae based on consideration of future biomass biorefinery. Z. mobilis has been studied extensively on both fundamental and applied level, which will provide a basis for industrial biotechnology in the future. Furthermore, metabolic engineering of Z. mobilis for enhancing bio-ethanol production from biomass resources has been significantly promoted by different methods (i.e. mutagenesis, adaptive laboratory evolution, specific gene knock-out, and metabolic engineering). In addition, the feasibility of representative metabolites, i.e. sorbitol, bionic acid, levan, succinic acid, isobutanol, and isobutanol produced by Z. mobilis and the strategies for strain improvements are also discussed or highlighted in this paper. Moreover, this review will present some guidelines for future developments in the bio-based chemical production using Z. mobilis as a novel industrial platform for future biofineries.

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