大腸桿菌對(duì)氮限制的適應(yīng)性進(jìn)化
發(fā)布時(shí)間：2019-02-27 15:20
【摘要】：自然界中生物常常面臨氮資源限制,它們可能會(huì)采用不同的策略來(lái)適應(yīng).通過(guò)比較現(xiàn)存物種的研究認(rèn)為生物采取的是節(jié)約氮的策略,而進(jìn)化實(shí)驗(yàn)的研究發(fā)現(xiàn)生物提高了吸收氮資源的能力.這2類研究都有一些方法缺陷,因此本研究設(shè)計(jì)了一個(gè)更系統(tǒng)的進(jìn)化實(shí)驗(yàn),讓大腸桿菌種群在2種氮資源環(huán)境中進(jìn)化1 300代,分析其對(duì)不同氮資源環(huán)境的適應(yīng)性進(jìn)化.1 300代后,2種氮資源環(huán)境中進(jìn)化的大腸桿菌株系適合度均提高,低氮進(jìn)化株系適合度提升幅度大于高氮進(jìn)化株系.與祖先相比,低氮株系氮質(zhì)量分?jǐn)?shù)和DNA質(zhì)量分?jǐn)?shù)均顯著提高,碳、氮質(zhì)量比顯著降低,而高氮株系在RNA質(zhì)量分?jǐn)?shù)上顯著提高.說(shuō)明在本研究體系中,大腸桿菌采用了增強(qiáng)氮獲取能力的策略來(lái)適應(yīng)氮限制,而不是節(jié)約氮.
[Abstract]:Living things in nature often face nitrogen resource constraints, and they may adopt different strategies to adapt. Compared with the existing species, it is believed that organisms adopt the strategy of saving nitrogen, while evolutionary experiments show that organisms improve their ability to absorb nitrogen resources. These two types of studies have some methodological defects, so this study designed a more systematic evolutionary experiment to let the Escherichia coli population evolve 1,300 generations in two nitrogen resource environments. The adaptive evolution of these strains to different nitrogen resources and environments was analyzed. 1 300 generations later, the fitness of the two strains was improved, and that of the low nitrogen evolutionary strain was greater than that of the high nitrogen evolutionary strain. Compared with their ancestors, the nitrogen mass fraction and DNA mass fraction of low nitrogen plant lines were significantly increased, while the mass ratio of carbon to nitrogen was significantly decreased, while the mass fraction of RNA of high nitrogen lines was significantly increased. In this study, E. coli used the strategy of enhancing the ability of nitrogen acquisition to adapt to nitrogen limitation, rather than saving nitrogen.
【作者單位】： 北京師范大學(xué)生物多樣性與生態(tài)工程教育部重點(diǎn)實(shí)驗(yàn)室;
【基金】：國(guó)家自然科學(xué)基金資助項(xiàng)目(31030014)
【分類號(hào)】：R378
本文編號(hào)：2431383
[Abstract]:Living things in nature often face nitrogen resource constraints, and they may adopt different strategies to adapt. Compared with the existing species, it is believed that organisms adopt the strategy of saving nitrogen, while evolutionary experiments show that organisms improve their ability to absorb nitrogen resources. These two types of studies have some methodological defects, so this study designed a more systematic evolutionary experiment to let the Escherichia coli population evolve 1,300 generations in two nitrogen resource environments. The adaptive evolution of these strains to different nitrogen resources and environments was analyzed. 1 300 generations later, the fitness of the two strains was improved, and that of the low nitrogen evolutionary strain was greater than that of the high nitrogen evolutionary strain. Compared with their ancestors, the nitrogen mass fraction and DNA mass fraction of low nitrogen plant lines were significantly increased, while the mass ratio of carbon to nitrogen was significantly decreased, while the mass fraction of RNA of high nitrogen lines was significantly increased. In this study, E. coli used the strategy of enhancing the ability of nitrogen acquisition to adapt to nitrogen limitation, rather than saving nitrogen.
【作者單位】： 北京師范大學(xué)生物多樣性與生態(tài)工程教育部重點(diǎn)實(shí)驗(yàn)室;
【基金】：國(guó)家自然科學(xué)基金資助項(xiàng)目(31030014)
【分類號(hào)】：R378
【相似文獻(xiàn)】
中國(guó)期刊全文數(shù)據(jù)庫(kù) 前1條
1 張馳宇;魏繼福;;SARS-CoV由果子貍向人類跨種傳播中S蛋白的適應(yīng)性進(jìn)化研究[J];江蘇大學(xué)學(xué)報(bào)(醫(yī)學(xué)版);2006年05期
中國(guó)碩士學(xué)位論文全文數(shù)據(jù)庫(kù) 前1條
1 丁娜;HIV-1和A/H1N1的適應(yīng)性進(jìn)化研究及HIV-1重組分析方法的評(píng)價(jià)[D];江蘇大學(xué);2010年
，本文編號(hào)：2431383
本文鏈接：http://sikaile.net/xiyixuelunwen/2431383.html
最近更新
教材專著
