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331.
Woyke T Teeling H Ivanova NN Huntemann M Richter M Gloeckner FO Boffelli D Anderson IJ Barry KW Shapiro HJ Szeto E Kyrpides NC Mussmann M Amann R Bergin C Ruehland C Rubin EM Dubilier N 《Nature》2006,443(7114):950-955
Symbioses between bacteria and eukaryotes are ubiquitous, yet our understanding of the interactions driving these associations is hampered by our inability to cultivate most host-associated microbes. Here we use a metagenomic approach to describe four co-occurring symbionts from the marine oligochaete Olavius algarvensis, a worm lacking a mouth, gut and nephridia. Shotgun sequencing and metabolic pathway reconstruction revealed that the symbionts are sulphur-oxidizing and sulphate-reducing bacteria, all of which are capable of carbon fixation, thus providing the host with multiple sources of nutrition. Molecular evidence for the uptake and recycling of worm waste products by the symbionts suggests how the worm could eliminate its excretory system, an adaptation unique among annelid worms. We propose a model that describes how the versatile metabolism within this symbiotic consortium provides the host with an optimal energy supply as it shuttles between the upper oxic and lower anoxic coastal sediments that it inhabits. 相似文献
332.
Scherer SE Muzny DM Buhay CJ Chen R Cree A Ding Y Dugan-Rocha S Gill R Gunaratne P Harris RA Hawes AC Hernandez J Hodgson AV Hume J Jackson A Khan ZM Kovar-Smith C Lewis LR Lozado RJ Metzker ML Milosavljevic A Miner GR Montgomery KT Morgan MB Nazareth LV Scott G Sodergren E Song XZ Steffen D Lovering RC Wheeler DA Worley KC Yuan Y Zhang Z Adams CQ Ansari-Lari MA Ayele M Brown MJ Chen G Chen Z Clerc-Blankenburg KP Davis C Delgado O Dinh HH Draper H Gonzalez-Garay ML Havlak P Jackson LR Jacob LS 《Nature》2006,440(7082):346-351
Human chromosome 12 contains more than 1,400 coding genes and 487 loci that have been directly implicated in human disease. The q arm of chromosome 12 contains one of the largest blocks of linkage disequilibrium found in the human genome. Here we present the finished sequence of human chromosome 12, which has been finished to high quality and spans approximately 132 megabases, representing approximately 4.5% of the human genome. Alignment of the human chromosome 12 sequence across vertebrates reveals the origin of individual segments in chicken, and a unique history of rearrangement through rodent and primate lineages. The rate of base substitutions in recent evolutionary history shows an overall slowing in hominids compared with primates and rodents. 相似文献
333.
Environmental chemistry: browning the waters 总被引:1,自引:0,他引:1
334.
335.
IntroductionChlorinated phenolic compounds,which aregenerated from a number of industrialmanufacturing processes,comprise the bulk of theenvironmental pollutants.Aqueous effluents fromindustrial operations such as polymeric resinproduction,oil refining,iron- steel,petroleum,pesticide,paint,solvent,pharmaceutics,woodpreserving chemicals,coke- oven,and paper andpulp industries contain chlorophenolic compounds.Their fate in the environment is of greatimportance as they are toxic,recalcitrant andb… 相似文献