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Electron acceptors for anaerobic oxidation of methane drive microbial community structure and diversity in mud volcanoes 下载免费PDF全文
Ge Ren Anzhou Ma Yanfen Zhang Ye Deng Guodong Zheng Xuliang Zhuang Guoqiang Zhuang Danielle Fortin 《Environmental microbiology》2018,20(7):2370-2385
Mud volcanoes (MVs) emit globally significant quantities of methane into the atmosphere, however, methane cycling in such environments is not yet fully understood, as the roles of microbes and their associated biogeochemical processes have been largely overlooked. Here, we used data from high‐throughput sequencing of microbial 16S rRNA gene amplicons from six MVs in the Junggar Basin in northwest China to quantify patterns of diversity and characterize the community structure of archaea and bacteria. We found anaerobic methanotrophs and diverse sulfate‐ and iron‐reducing microbes in all of the samples, and the diversity of both archaeal and bacterial communities was strongly linked to the concentrations of sulfate, iron and nitrate, which could act as electron acceptors in anaerobic oxidation of methane (AOM). The impacts of sulfate/iron/nitrate on AOM in the MVs were verified by microcosm experiments. Further, two representative MVs were selected to explore the microbial interactions based on phylogenetic molecular ecological networks. The sites showed distinct network structures, key species and microbial interactions, with more complex and numerous linkages between methane‐cycling microbes and their partners being observed in the iron/sulfate‐rich MV. These findings suggest that electron acceptors are important factors driving the structure of microbial communities in these methane‐rich environments. 相似文献
35.
本文对北京西山海拔300米的26年生人工栓皮栎林的生物量作了测定。粮据十株伐倒的标准木分别取得乔木各部分的干重。采用W=a(D2H)b的幂函数方程,获得每公顷土地上的树干重32.16吨,枝条重9.85吨、叶重1.68吨、根重9.95吨。对灌木和草本植物采用收割法作测定:灌木的地上部分每公顷为1.33吨,地下部分为2.3吨;草本植物的地上部分每公顷为0.15吨,地下部分为0.8吨。所以栓皮栎的地上部分总生物量每公顷为45.17吨,地下部分13.05吨,总计58.22吨。 相似文献
36.
Qizhang Long Wenwei Zhang Peng Wang Wenbiao Shen Tong Zhou Nannan Liu Ren Wang Ling Jiang Jiexue Huang Yihua Wang Yuqiang Liu Jianmin Wan 《Journal of Plant Biology》2013,56(4):232-242
Lipoxygenases (LOXs) are enzymes involved in lipid peroxidation. Here we reported the identification, molecular and functional characterization of the gene encoding rice (Oryza sativa L.) seed LOX3 (sLOX3). Via a map-based cloning strategy we identified Os03g0700400 as the candidate gene encoding sLOX3. Further functional complementary test and biochemical characterization of the recombinant Os03g0700400 protein verified the identification. The sLOX3 gene was highly expressed in roots, moderately in embryos and very weakly in leaves, leaf sheaths and stems. Transient expression experiment (in rice protoplasts) and subsequent laser confocal microscopic analysis demonstrated that the sLOX3 protein was localized into the cytosol. We next showed that overexpression of sLOX3 in a japonica sLOX3-normal rice cultivar, Wuyunjing 7 accelerated the decrease of seed germination ability when the seeds were routinely stored, which demonstrated that sLOX3 had a negative effect on seed longevity (storability). Meanwhile, an increased occurrence of embryo decay was observed in the same transgenic seeds, suggesting that sLOX3 might negatively affect seed longevity by facilitating colonization of particular seed pathogens. Our result forwarded the understanding of the effects of 9-LOX on rice seed longevity. 相似文献
37.
SPOP Promotes Nanog Destruction to Suppress Stem Cell Traits and Prostate Cancer Progression 总被引:1,自引:0,他引:1
38.
Jafar A. Mammadov Wei Chen Ruihua Ren Reetal Pai Wesley Marchione Feyruz Yalçin Hanneke Witsenboer Thomas W. Greene Steven A. Thompson Siva P. Kumpatla 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):577-588
The duplicated and the highly repetitive nature of the maize genome has historically impeded the development of true single
nucleotide polymorphism (SNP) markers in this crop. Recent advances in genome complexity reduction methods coupled with sequencing-by-synthesis
technologies permit the implementation of efficient genome-wide SNP discovery in maize. In this study, we have applied Complexity
Reduction of Polymorphic Sequences technology (Keygene N.V., Wageningen, The Netherlands) for the identification of informative
SNPs between two genetically distinct maize inbred lines of North and South American origins. This approach resulted in the
discovery of 1,123 putative SNPs representing low and single copy loci. In silico and experimental (Illumina GoldenGate (GG)
assay) validation of putative SNPs resulted in mapping of 604 markers, out of which 188 SNPs represented 43 haplotype blocks
distributed across all ten chromosomes. We have determined and clearly stated a specific combination of stringent criteria
(>0.3 minor allele frequency, >0.8 GenTrainScore and >0.5 Chi_test100 score) necessary for the identification of highly polymorphic
and genetically stable SNP markers. Due to these criteria, we identified a subset of 120 high-quality SNP markers to leverage
in GG assay-based marker-assisted selection projects. A total of 32 high-quality SNPs represented 21 haplotypes out of 43
identified in this study. The information on the selection criteria of highly polymorphic SNPs in a complex genome such as
maize and the public availability of these SNP assays will be of great value for the maize molecular genetics and breeding
community. 相似文献
39.
It was well known that beta-amyloid (Abeta) and tau protein play an important role in pathological procedure of Alzheimer's disease (AD), a senile dementia. The growth inhibitory factor (GIF, also named metallothionein-3, MT-3) had been demonstrated to inhibit the outgrowth of cortex neurons in the medium with extract of the AD patient brain. In our experiments, it was found that the neurons of cortex and the PC12 (pheochromocytoma) cells could be protected from the cytotoxicity of beta-amyloid 25-35 in presence of GIF and its domains. Additionally, GIF can scavenge the hydroxyl radical efficiently in CytC-VitC radical producing system and its alpha-domain shown more effective potentials than its beta-domain. The electron paramagnetic resonance spectra also show that the alpha-domain has more potential ability for eliminating reactive oxygen free radicals than its beta-domain. The results suggest that GIF could act as an efficient scavenger against free radicals in vitro and the alpha-domain in GIF molecule shows more potential in protecting against reactive oxygen species injury than the beta-domain. 相似文献