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1.
J Obstet Gynaecol Res ; 48(11): 2888-2895, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36055894

RESUMO

OBJECTIVES: This study aimed to investigate the long-term sexual function of patients with cervical cancer who underwent treatment and to explore influential factors. METHODS: This retrospective cross-sectional study was conducted at Peking University First Hospital in (Beijing, China). A total of 207 patients, who were diagnosed with Stage IA-IIA cervical cancer and had undergone surgical treatment (some patients had also been treated with adjuvant radiotherapy and chemotherapy) between January 2010 and August 2020, completed questionnaires via telephone. The median time since diagnosis was 54 (range, 13-138) months. Sexual function was assessed using the validated short form of Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12). The multivariate logistic regression analysis was performed to determine factors influencing sexual function after treatment. RESULTS: The mean preoperative PISQ-12 score was 39.42 ± 3.922, and the mean postoperative PISQ-12 score was 32.60 ± 6.592, indicating a significant decrease in postoperative PISQ-12 score compared with preoperation (p < 0.001). In total, 49.8% of the patients had sexual dysfunction after treatment. According to the results of the multivariate logistic regression analysis, longer follow-up (months), ovariectomy, lack of hormone replacement therapy after ovariectomy and adjuvant radiotherapy were significantly associated with sexual dysfunction after treatment (p < 0.05). There was no significant correlation among surgical method, tumor stage, adjuvant chemotherapy, and sexual dysfunction after treatment. CONCLUSIONS: The sexual function of cervical cancer survivors significantly decreased after treatment, which was related to the length of follow-up, ovariectomy, and adjuvant radiotherapy. Hormone replacement therapy after ovariectomy can help patients to improve their sexual function.


Assuntos
Sobreviventes de Câncer , Prolapso de Órgão Pélvico , Disfunções Sexuais Fisiológicas , Neoplasias do Colo do Útero , Feminino , Humanos , Estudos Transversais , Estudos Retrospectivos , Neoplasias do Colo do Útero/complicações , Qualidade de Vida , Prolapso de Órgão Pélvico/complicações , Inquéritos e Questionários , Comportamento Sexual
2.
Microb Ecol ; 80(1): 120-132, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31982930

RESUMO

Propionate is one of the major intermediates in anaerobic digestion of organic waste to CO2 and CH4. In methanogenic environments, propionate is degraded through a mutualistic interaction between symbiotic propionate oxidizers and methanogens. Although temperature heavily influences the microbial ecology and performance of methanogenic processes, its effect on syntrophic interaction during propionate degradation remains poorly understood. In this study, metagenomics and metatranscriptomics were employed to compare mesophilic and thermophilic propionate degradation communities. Mesophilic propionate degradation involved multiple syntrophic organisms (Syntrophobacter, Smithella, and Syntrophomonas), pathways, interactions, and preference toward formate-based electron transfer to methanogenic partners (i.e., Methanoculleus). In thermophilic propionate degradation, one syntrophic organism predominated (Pelotomaculum), interspecies H2 transfer played a major role, and phylogenetically and metabolically diverse H2-oxidizing methanogens were present (i.e., Methanoculleus, Methanothermobacter, and Methanomassiliicoccus). This study showed that microbial interactions, metabolic pathways, and niche diversity are distinct between mesophilic and thermophilic microbial communities responsible for syntrophic propionate degradation.


Assuntos
Archaea/metabolismo , Bactérias/metabolismo , Propionatos/metabolismo , Anaerobiose , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Reatores Biológicos , Transporte de Elétrons , Genoma Arqueal , Genoma Bacteriano , Metagenômica , Temperatura
3.
Appl Microbiol Biotechnol ; 103(20): 8631-8645, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418053

RESUMO

Syntrophic oxidization of acetate and propionate are both critical steps of methanogenesis during thermophilic anaerobic digestion. However, knowledge on syntrophic acetate-oxidizing bacteria (SAOB) and syntrophic propionate-oxidizing bacteria (SPOB) is limited because of the difficulty in pure culture isolation due to symbiotic relationship. In this study, two thermophilic acetate-fed anaerobic chemostats, ATL (dilution rate of 0.025 day-1) and ATH (0.05 day-1) and one thermophilic propionate-fed anaerobic chemostat PTL (0.025 day-1) were constructed, AOB and POB in these chemostats were studied via microbial community analysis and DNA stable-isotope probing (SIP). The results showed that, in addition to Tepidanaerobacter, a known SAOB, species of Thauera, Thermodesulfovibrio, Anaerobaculum, Ruminiclostridium, Comamonas, and uncultured bacteria belonging to Lentimicrobiaceae, o_MBA03, Thermoanaerobacteraceae, Anaerolineaceae, Clostridiales, and Ruminococcaceae were determined to be potential AOB in chemostats. Pelotomaculum was the key SPOB detected in the propionate-fed chemostat. Based on the intense fluorescence of coenzyme F420, majority of Methanosarcina cells in acetate-fed chemostats were involved in hydrogenotrophic methanogenesis, suggesting the existence of highly active SAOB among the detected AOB. In the propionate-fed chemostat, most of the species detected as AOB were similar to those detected in the acetate-fed chemostats, suggesting the contribution of the syntrophic acetate oxidization pathway for methane generation. These results revealed the existence of previously unknown AOB with high diversity in thermophilic chemostats and suggested that methanogenesis from acetate via the syntrophic oxidization pathway is relevant for thermophilic anaerobic digestion.


Assuntos
Acetatos/metabolismo , Bactérias Anaeróbias/classificação , Biota , Microbiologia Ambiental , Metano/metabolismo , Methanosarcina/classificação , Anaerobiose , Bactérias Anaeróbias/genética , Bactérias Anaeróbias/metabolismo , Methanosarcina/genética , Methanosarcina/metabolismo , Oxirredução , Propionatos/metabolismo
4.
Zhongguo Zhong Yao Za Zhi ; 43(4): 672-675, 2018 Feb.
Artigo em Zh | MEDLINE | ID: mdl-29600639

RESUMO

As traditional Chinese medicinal herbs, Physalis plants have a variety of pharmacological activities, such as anti-inflammatory, anti-oxidant, and anti-cancer effects, and have been used for the treatment of malaria, rheumatism, hepatitis, asthma, and cancer. In addition to the medicinal value, many Physalis species are also the high-grade nutrition health care fruits, can be made canned and candied etc. In the study, the application progress of DNA molecular marker technologies in medicinal Physalis plants in recent years was reviewed, in order to provide an important molecular technical basis for the identification, classification and rational development and protection of medicinal Physalis resources.


Assuntos
DNA de Plantas/genética , Marcadores Genéticos , Physalis/genética , Plantas Medicinais/genética
5.
Appl Microbiol Biotechnol ; 100(5): 2417-27, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26549238

RESUMO

The feasibility of the anaerobic ammonium oxidation (anammox) process to treat synthetic swine wastewater containing antibiotics and heavy metals was studied in this work. Nitrogen removal performance and granule characteristics were tracked by continuous-flow monitoring to evaluate the long-term joint effects of Cu and Zn and of Cu and oxytetracycline (OTC). Cu and Zn with a joint loading rate (JLR) of 0.04 kg m(-3) day(-1) did not affect the performance, while a JLR of 0.12 kg m(-3) day(-1) caused a rapid collapse in performance. Cu and OTC addition with a JLR of 0.04 kg m(-3) day(-1) for approximately 2 weeks induced significant nitrite accumulation. Granule characteristic analysis elucidated the disparate inhibition mechanisms of heavy metals and antibiotics: the internalization of heavy metals caused metabolic disorders, whereas OTC functioned as a growth retarder. However, anammox reactors could adapt to a JLR of 0.04 kg m(-3) day(-1) via self-regulation during the acclimatization to subinhibitory concentrations, which had a stable nitrogen removal rate (>8.5 kg m(-3) day(-1)) and removal rate efficiency (>75 %) for reactors with Cu-OTC addition. Therefore, this study supports the great potential of using anammox granules to treat swine wastewater.


Assuntos
Amônia/metabolismo , Antibacterianos/metabolismo , Metais Pesados/metabolismo , Consórcios Microbianos/efeitos dos fármacos , Águas Residuárias/microbiologia , Anaerobiose , Animais , Oxirredução , Suínos , Tempo , Purificação da Água
6.
Appl Microbiol Biotechnol ; 99(7): 3221-32, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25398286

RESUMO

In the present study, the short- and long-term effects of Zn(II) on the anaerobic ammonium oxidation (anammox) performance and sludge characteristics were evaluated. The anammox activity decreased with increasing Zn(II) concentration and pre-exposure time in short-term tests. The half maximal inhibitory concentration (IC50) of Zn(II) was found to be 25.0 mg L(-1). The 24 and 48-h pre-exposure time was a restricted factor impacting the anammox activity, and washing the inhibited sludge with buffer solution only worked under 0 and 24-h pre-exposure time. The anammox sludge could tolerate 5 mg L(-1) Zn(II) but was suppressed at 8 mg L(-1). The inhibited performance could be remitted, as the combination strategies were applied, and after the short term of recovery period, the inhibited sludge characteristics were remitted to the normal.


Assuntos
Amônia/metabolismo , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Zinco/farmacologia , Anaerobiose , Biomassa , Reatores Biológicos/microbiologia , Heme/análogos & derivados , Heme/metabolismo , Concentração Inibidora 50 , Cinética , Consórcios Microbianos/efeitos dos fármacos , Modelos Teóricos , Oxirredução
7.
Biochem Genet ; 52(3-4): 127-36, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24213846

RESUMO

Dendrobium plants are important commercial herbs in China, widely used in traditional medicine and ornamental horticulture. In this study, sequence-related amplified polymorphism (SRAP) markers were applied to molecular phylogeny analysis and species identification of 31 Chinese Dendrobium species. Fourteen SRAP primer pairs produced 727 loci, 97% of which (706) showed polymorphism. Average polymorphism information content of the SRAP pairs was 0.987 (0.982-0.991), showing that plenty of genetic diversity exists at the interspecies level of Chinese Dendrobium. The molecular phylogeny analysis (UPGMA) grouped the 31 Dendrobium species into six clusters. We obtained 18 species-specific markers, which can be used to identify 10 of the 31 species. Our results indicate the SRAP marker system is informative and would facilitate further application in germplasm appraisal, evolution, and genetic diversity studies in the genus Dendrobium.


Assuntos
DNA de Plantas/genética , Dendrobium/classificação , Dendrobium/genética , China , Marcadores Genéticos , Variação Genética , Filogenia , Folhas de Planta/genética , Polimorfismo Genético , Especificidade da Espécie
8.
Zootaxa ; 5231(5): 552-566, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37045126

RESUMO

A species of Trichotylenchus nematode was isolated from the rhizosphere of banana root in Leizhou City, Guangdong Province, China. The species assumes the following characteristics: open C-shaped body; head offset from body; lateral field with three incisures, pharyngeal and tail regions irregularly areolated; stylet 18.6-20.7 µm long; pharyngeal gland not extending over intestine; fibrous tissue present in the intestine; post-anal intestinal sac present; elongate-subcylindroid tail, bluntly conoid terminus, lack of striations, and containing 34-44 annuli. In addition, scanning electron microscopy was used to elucidate some morphological details, but only some juveniles were observed. Partial 18S rRNA, ITS, and 28S D2-D3 expansion sequences were amplified with universal primers and deposited in GenBank under accession numbers ON622716, ON622717, and ON622714, respectively. Here, this species was identified as T. dispersus [(Siddiqi & Sharma, 1995) Geraert, 2011].


Assuntos
Tylenchoidea , Animais , Tylenchoidea/genética , Rizosfera , China , Bases de Dados de Ácidos Nucleicos
9.
Virol J ; 9: 113, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22698086

RESUMO

BACKGROUND: Citrus tristeza virus (CTV), a member of the genus Closterovirus within the family Closteroviridae, is the causal agent of citrus tristeza disease. Previous studies revealed that the negative selection, RNA recombination and gene flow were the most important forces that drove CTV evolution. However, the CTV codon usage was not studied and thus its role in CTV evolution remains unknown. RESULTS: A detailed comparative analysis of CTV codon usage pattern was done in this study. Results of the study show that although in general CTV does not have a high degree of codon usage bias, the codon usage of CTV has a high level of resemblance to its host codon usage. In addition, our data indicate that the codon usage resemblance is only observed for the woody plant-infecting closteroviruses but not the closteroviruses infecting the herbaceous host plants, suggesting the existence of different virus-host interactions between the herbaceous plant-infecting and woody plant-infecting closteroviruses. CONCLUSION: Based on the results, we suggest that in addition to RNA recombination, negative selection and gene flow, host plant codon usage selection can also affect CTV evolution.


Assuntos
Adaptação Biológica , Citrus/virologia , Closterovirus/genética , Códon , Doenças das Plantas/virologia , Seleção Genética
10.
Am J Bot ; 99(10): e415-20, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23028002

RESUMO

PREMISE OF THE STUDY: Expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers were developed in Dendrobium officinale by screening a cDNA library. The loci were verified by sequencing and explored for polymorphism among 19 genotypes and transferability among 30 other distantly related Dendrobium species. • METHODS AND RESULTS: One hundred ten EST-SSRs were developed, and a set of 20 amplified two to six nucleotide repeats with a mean number of 2.5 alleles per locus and with an observed heterozygosity and polymorphism information content per locus ranging from 0.3463 to 0.9003 and 0.0997 to 0.6537 in 19 D. officinale genotypes, respectively. Furthermore, 92 of these markers have cross-taxa transferability, ranging from 6.45% to 100% among 30 other distantly related Dendrobium species. • CONCLUSIONS: The developed markers have potential for application in germplasm appraisal, genetic diversity study, genetic mapping, and molecular breeding in D. officinale and other congeneric species.


Assuntos
Dendrobium/genética , Etiquetas de Sequências Expressas , Repetições de Microssatélites/genética , Marcadores Genéticos , Variação Genética , Dados de Sequência Molecular
11.
Front Microbiol ; 13: 1098814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687577

RESUMO

Microorganisms in anaerobic digestion (AD) are easily affected by ammonia, especially acetoclastic methanogens. Thus, in ammonia-suppressed AD systems, acetate degradation is reported to be carried out mainly by the cooperation of syntrophic acetate oxidizers and hydrogenotrophic methanogens. Previous studies have revealed ammonia inhibition on microbial flora by AD performance, but the effect mechanism of ammonia on microbial metabolism remains poorly understood. In this study, we constructed a mesophilic chemostat fed with acetate as the sole carbon source, gradually increased the total ammonia nitrogen (TAN) concentration from 1 g L-1 to 6 g L-1, and employed the 16S rRNA gene, metagenomics, and metatranscriptomics analysis to characterize the microbial community structure and metabolic behavior. The results showed that even at the TAN of 6 g L-1 (pH 7.5), the methanogenesis kept normal, the biogas production was approximately 92% of that at TAN of 1 g L-1 and the acetate degradation ratio reached 99%, suggesting the strong TAN tolerance of the microbial community enriched. 16S rRNA gene analysis suggested that the microbial community structure changed along with the TAN concentration. Methanothrix predominated in methanogens all the time, in which the dominant species was gradually replaced from M. soehngenii to M. harundinacea with the increased TAN. Dominant bacterial species also changed and Proteiniphilum showed a significant positive correlation with increased TAN. Meta-omics analysis showed that the absolute dominant microorganisms at TAN of 6 g L-1 were M. harundinacea and Proteiniphilum, both of which highly expressed genes for anti-oxidative stress. M. harundinacea and the second dominant methanogen Methanosarcina highly expressed both acetate cleavage and CO2 reduction pathways, suggesting the possibility that these two pathways contributed to methanogenesis together. Proteiniphilum and some other species in Firmicutes and Synergistetes were likely acetate oxidizers in the community as they highly expressed genes for syntrophic acetate oxidization, H2 generation, and electron transfer. These results suggested that Proteiniphilum as well as M. harundinacea have strong ammonia tolerance and played critical roles in acetate degradation under ammonia-suppressed conditions. The achievements of the study would contribute to the regulation and management of the AD process.

12.
Appl Biochem Biotechnol ; 191(3): 1010-1026, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31950447

RESUMO

Isovalerate is one of the key intermediates during anaerobic digestion treating protein-containing waste/wastewater. Investigating the effect of different kinds of inhibitors on isovalerate-degrading microbial community is necessary to develop measures for improving the effectiveness of the treatment plants. In the present study, dynamic changes in the isovalerate-degrading microbial community in presence of inhibitors (ammonium, sulfide, mixed ammonium and sulfide, and chlortetracycline (CTC)) were investigated using high-throughput sequencing of 16S rRNA gene. Our observations showed that the isovalerate-degrading microbial community responded differently to different inhibitors and that the isovalerate degradation and gas production were strongly repressed by each inhibitor. We found that sulfide inhibited both isovalerate oxidation followed by methanogenesis, while ammonium, mixed ammonium and sulfide, and CTC mainly inhibited isovalerate oxidation. Genera classified into Proteobacteria and Chloroflexi were less sensitive to inhibitors. The two dominant genera, which are potential syntrophic isovalerate oxidizers, exhibited different responses to inhibitors that the unclassified_Peptococcaceae_3 was more sensitive to inhibitors than the unclassified_Syntrophaceae. Upon comparison to acetoclastic methanogen Methanosaeta, hydrogenotrophic methanogens Methanoculleus and Methanobacterium were less sensitive to inhibitors.


Assuntos
Hemiterpenos/química , Metano/química , Microbiota , Ácidos Pentanoicos/química , Compostos de Amônio/química , Anaerobiose , Reatores Biológicos/microbiologia , Chloroflexi/efeitos dos fármacos , Clortetraciclina/química , Ácidos Graxos Voláteis/química , Microbiologia Industrial , Methanobacterium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nitrogênio/química , Peptococcaceae/efeitos dos fármacos , Proteobactérias/efeitos dos fármacos , RNA Ribossômico 16S/genética , Sulfetos/química , Águas Residuárias/química , Poluentes Químicos da Água , Purificação da Água/métodos
13.
J Biosci Bioeng ; 129(4): 476-485, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31699533

RESUMO

Investigating the effects of different kinds of inhibitors on the activity and structure of acetate-degrading microbial community involved in methane fermentation is critically important for developing countermeasures to make the fermentation process stable under different inhibitory conditions. In the present study, a mesophilic chemostat fed with acetate as the sole carbon source was constructed. Microbial community analysis based on high-throughput sequencing of 16S rRNA revealed that Methanothrix was the dominant methanogen and a variety of bacteria including acetate-oxidizing bacteria such as Tepidanaerobacter, Mesotoga, Geovibrio, and Geobacter were found. The activity and dynamic changes of the acetate-degrading microbial community under different inhibitory conditions were investigated. Addition of 600 mg L-1 ammonium and 150 mg L-1 sulfide reduced nearly half of the biogas production. The response of microbial community to sulfide inhibition was quicker than ammonium but the structure could recover in a short time. Addition of 8 mg L-1 chlortetracycline (CTC) and 160 mg L-1 enrofloxacin (EFX) exhibited a similar inhibitory effect on biogas production, with approximately 35% reduction. Compared to ammonium and sulfide, antibiotics showed stronger selective inhibition on some bacterial species. The genera related to acetate-oxidizing and sulfate-reducing bacteria showed stronger tolerance to CTC, which may be due to their low growth rates. Network analysis suggested that some genera which had close phylogenic relationship and similar functions showed constant positive correlation under different inhibitory conditions.


Assuntos
Acetatos/metabolismo , Antibacterianos/farmacologia , Bactérias/crescimento & desenvolvimento , Metano/metabolismo , Microbiota/efeitos dos fármacos , Animais , Antibacterianos/isolamento & purificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Bactérias Anaeróbias/efeitos dos fármacos , Bactérias Anaeróbias/genética , Bactérias Anaeróbias/metabolismo , Biocombustíveis , Reatores Biológicos/microbiologia , Carbono/metabolismo , Galinhas , Fermentação/efeitos dos fármacos , Geobacter/efeitos dos fármacos , Geobacter/genética , Geobacter/crescimento & desenvolvimento , Geobacter/metabolismo , Testes de Sensibilidade Microbiana , Microbiota/genética , Filogenia , RNA Ribossômico 16S/genética , Águas Residuárias/química , Águas Residuárias/microbiologia
14.
Genetica ; 136(3): 391-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19085060

RESUMO

Spring orchid (Cymbidium goeringii) is a popular flowering plant species. There have been few molecular studies of the genetic diversity and conservation genetics on this species. An assessment of the level of genetic diversity in cultivated spring orchid would facilitate development of the future germplasm conservation for cultivar improvement. In the present study, DNA markers of intersimple sequence repeats (ISSR) were identified and the ISSR fingerprinting technique was used to evaluate genetic diversity in C. goeringii cultivars. Twenty-five ISSR primers were selected to produce a total of 224 ISSR loci for evaluation of the genetic diversity. A wide genetic variation was found in the 50 tested cultivars with Nei's gene diversity (H = 0.2241) and 93.75% of polymorphic loci. Fifty cultivars were unequivocally distinguished based on ISSR fingerprinting. Cultivar-specific ISSR markers were identified in seven of 50 tested cultivars. Unweighted pair-group mean analysis (UPGMA) and principal coordinates analysis (PCA) grouped them into two clusters: one composed the cultivars mainly from Japan, and the other contained three major subclusters mainly from China. Two Chinese subclusters were generally consistent with horticultural classification, and the third Chinese subcluster contained cultivars from various horticultural groups. Our results suggest that the ISSR technique provides a powerful tool for cultivar identification and establishment of genetic relationships of cultivars in C. goeringii.


Assuntos
Variação Genética , Repetições Minissatélites/genética , Orchidaceae/classificação , Orchidaceae/genética , Análise por Conglomerados , Conservação dos Recursos Naturais , Marcadores Genéticos/genética , Polimorfismo Genético , Estações do Ano , Especificidade da Espécie
15.
Sci Rep ; 9(1): 17396, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31758023

RESUMO

Propionate is one of the most important intermediates of anaerobic fermentation. Its oxidation performed by syntrophic propionate-oxidizing bacteria coupled with hydrogenotrophic methanogens is considered to be a rate-limiting step for methane production. However, the current understanding of SPOB is limited due to the difficulty of pure culture isolation. In the present study, two anaerobic chemostats fed with propionate as the sole carbon source were operated at different dilution rates (0.05 d-1 and 0.15 d-1). The propionate- and acetate-oxidizing bacteria in the two methanogenic chemostats were investigated combining DNA-stable isotope probing (DNA-SIP) and 16S rRNA gene high-throughput sequencing. The results of DNA-SIP with 13C-propionate/acetate suggested that, Smithella, Syntrophobacter, Cryptanaerobacter, and unclassified Rhodospirillaceae may be putative propionate-oxidizing bacteria; unclassified Spirochaetaceae, unclassified Synergistaceae, unclassified Elusimicrobia, Mesotoga, and Gracilibacter may contribute to acetate oxidation; unclassified Syntrophaceae and Syntrophomonas may be butyrate oxidizers. By DNA-SIP, unclassified OTUs with 16S rRNA gene abundance higher than 62% of total Bacteria in the PL chemostat and 38% in the PH chemostat were revealed to be related to the degradation of propionate. These results suggest that a variety of uncultured bacteria contribute to propionate degradation during anaerobic digestion. The functions and metabolic characteristics of these bacteria require further investigation.


Assuntos
Acetatos/metabolismo , Bactérias/isolamento & purificação , Reatores Biológicos/microbiologia , DNA/química , Marcação por Isótopo/métodos , Propionatos/metabolismo , Anaerobiose/fisiologia , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Sondas de DNA/química , Microbiologia Ambiental , Fermentação , Microbiota/genética , Oxirredução , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética
16.
Appl Biochem Biotechnol ; 189(1): 233-248, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30972704

RESUMO

Propionate is a crucial intermediate during methane fermentation. Investigating the effects of different kinds of inhibitors on the propionate-degrading microbial community is necessary to develop countermeasures for improving process stability. In the present study, under inhibitory conditions (acetate, propionate, sulfide, and ammonium addition), the dynamic changes of the propionate-degrading microbial community from a mesophilic chemostat fed with propionate as the sole carbon source were investigated using high-throughput sequencing of 16S rRNA. Sulfide and/or ammonia inhibited specific species in the microbial community. Compared with Syntrophobacter, Smithella was more resistant to inhibition by sulfide and/or ammonia. However, Syntrophobacter demonstrated greater tolerance than Smithella under acid inhibition conditions. Some genera that had close phylogenetic relationships and similar functions showed similar responses to different inhibitors.


Assuntos
Deltaproteobacteria/metabolismo , Metano/metabolismo , Microbiota , Propionatos/metabolismo , Biocombustíveis , Carbono/metabolismo , Deltaproteobacteria/genética , Ecossistema , Fermentação , RNA Ribossômico 16S/genética
17.
Yi Chuan ; 30(5): 627-32, 2008 May.
Artigo em Zh | MEDLINE | ID: mdl-18487154

RESUMO

ISSR was applied to detect the relationship between 16 Cymbidium species, and 836 bands were amplified with 15 primers, including 227 polymorphic bands. The polymorphic percentage is 27.2%. UPGMA results showed that the genetic distance were closest between C.goeringii (Rchb.f.) Rchb.f. and C. goeringii var. longibracteatum, and C.lancifolium Hook. was far away from the other 15 species. This result is quite similar to the traditional classification, indicating that the technique could supplement some information to traditional taxonomy in the molecular level.


Assuntos
Variação Genética/genética , Orchidaceae/genética , Sequências Repetitivas de Ácido Nucleico/genética , DNA de Plantas/genética , Orchidaceae/classificação , Filogenia , Reação em Cadeia da Polimerase
18.
J Gen Appl Microbiol ; 64(5): 221-231, 2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29760349

RESUMO

Acetate is a significant intermediate of anaerobic fermentation. There are two pathways for converting acetate to CH4 and CO2: acetoclastic methanogenesis by acetoclastic methanogens, and syntrophic acetate oxidation by acetate-oxidizing bacteria (AOB) and hydrogenotrophic methanogens. Detailed investigations of syntrophic acetate-oxidizing bacteria (SAOB) should contribute to the elucidation of the microbial mechanisms of methanogenesis. In this study, we investigated the major phylogenetic groups of acetate-utilizing bacteria (AUB) in a mesophilic methanogenic chemostat fed with acetate as the sole carbon source by using DNA stable isotope probing (SIP) technology. The results indicated that acetoclastic methanogenesis and acetate oxidization/hydrogenotrophic methanogenesis coexisted in the mesophilic chemostat fed with acetate, operated at a dilution rate of 0.1 d-1. OTU Ace13(9-17) (KU869530), Ace13(9-4) (KU667241), and Ace13(9-23) (KU667236), assigned to the phyla Firmicutes and Bacteroidetes, were probably potential SAOB in the chemostat, which needs further investigation. Species in the phyla Proteobacteria, Deferribacteres, Acidobacteria, Spirochaetes and Actinobacteria were probably capable of utilizing acetate for their growth. Methanoculleus was likely to be the preferred hydrogenotrophic methanogen for syntrophy with AOB in the chemostat.


Assuntos
Ácido Acético/metabolismo , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/isolamento & purificação , Reatores Biológicos/microbiologia , Metano/biossíntese , Filogenia , Bactérias Anaeróbias/genética , Bactérias Anaeróbias/metabolismo , Isótopos de Carbono/metabolismo , Marcação por Isótopo , Microbiota , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética
19.
Zhonghua Gan Zang Bing Za Zhi ; 15(3): 209-11, 2007 Mar.
Artigo em Zh | MEDLINE | ID: mdl-17407713

RESUMO

OBJECTIVE: To evaluate the role of adiponectin in regulating tumor necrosis factor alpha (TNF alpha) production and preventing fulminant autoimmunological damage of hepatocytes following concanavalin A (Con A) injection into mice. METHODS: Three days after recombinant plasmids pAA-neo-mAd were injected into the mice via the tail veins, Con A was injected into the mice. Mice transfected with empty pAA-neo vector served as controls. The serum levels of alanine aminotransferase (ALT), TNF alpha and adiponectin were detected, and histological examination of livers was carried out at different time points after the Con A injection. All results were subjected to statistical analyses. RESULTS: Histological examinations showed that the damage in livers of mice with high serum adiponectin levels was milder than that of the controls. The serum levels of ALT and TNF alpha were both lower than those of the controls (P less than 0.01, respectively). Statistical analyses showed the serum levels of ALT was negatively related to the levels of adiponectin in the sera (r=-0.5034). CONCLUSION: Adiponectin is effective in protecting hepatocytes from Con A-induced immunological injury. The mechanism of this protective effect may be caused by inhibiting the synthesis and/or release of TNF alpha.


Assuntos
Adiponectina/farmacologia , Doenças do Sistema Imunitário , Hepatopatias , Fígado/efeitos dos fármacos , Adiponectina/sangue , Alanina Transaminase/sangue , Animais , Concanavalina A/efeitos adversos , Feminino , Doenças do Sistema Imunitário/induzido quimicamente , Doenças do Sistema Imunitário/patologia , Doenças do Sistema Imunitário/prevenção & controle , Fígado/patologia , Hepatopatias/patologia , Hepatopatias/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/sangue
20.
Yi Chuan Xue Bao ; 33(11): 1047-52, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17112977

RESUMO

A sacB mutant was obtained by transposon IS10 inactivation of a plasmid pXT3sacB carrying the sacB gene. Sequencing of this mutant plasmid DNA (GenBank accession No. AY580883.1) showed that the IS10 flanking the 22 bp inverted repeats were 5'-CTGAGAGATCCCCTCATAATTT-3' and 5'-AAATCATTAGGGGATTCATCAG-3', which were the similar to those published in reports previously. However, the target sequence adjacent to IS10 was 5'-TGCTTGGTT-3' instead of the previously reported 5'-NGCTNAGCN-3'. To our knowledge, this is the first report on the novel insertion site of IS10. In addition, Southern blot hybridization confirmed that the mobile IS10 originated from the chromosomal DNA of the host strain Escherichia coli DH5alpha and that there were two copies in the DH5alpha genome.


Assuntos
Elementos de DNA Transponíveis/genética , Mutagênese Insercional/genética , Recombinação Genética/genética , Sequência de Bases , Southern Blotting , Enzimas de Restrição do DNA/metabolismo , Escherichia coli/genética , Plasmídeos/genética , Plasmídeos/metabolismo , Análise de Sequência de DNA
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