Abundance of narG, nirS, nirK, and nosZ genes of denitrifying bacteria during primary successions of a glacier foreland
Abundance of narG, nirS, nirK, and nosZ genes of denitrifying bacteria during primary successions of a glacier foreland
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DOI：
10.1128/aem.00439-06
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发表时间：
2006-09-01
影响因子：
4.4
通讯作者：
Philippot, Laurent
中科院分区：
文献类型：
--
作者：
Kandeler, Ellen;Deiglmayr, Kathrin;Philippot, Laurent
定量PCR的反硝化基因编码的硝酸盐，亚硝酸盐和一氧化二氮还原酶被用来研究跨越冰川前陆的反硝化细菌。从冰川消退的不同距离处收集的环境样品中含有16S rRNA靶分子的数量从每纳克DNA 4.9 X 10（5）到8.9 X 10（5）拷贝不等，但narG，nirK和nosZ靶分子的数量较少。因此，每纳克DNA的narG、nirK、nirS和nosZ拷贝数分别为2.1 × 10（3）至2.6 × 10（4）、7.4 × 10（2）至1.4 × 10（3）、2.5 × 10（2）至6.4 × 10（3）和1.2 × 10（3）至5.5 × 10（3）。每克土壤中16S rRNA基因的密度随着土壤发育的进行而增加。不同反硝化基因的密度和相对丰度表明，不同的反硝化菌群落在初级演替阶段发育不同：narG和nirS基因在初级演替早期的比例高于16SrRNA基因，而nirK和nosZ基因的比例没有随土壤年龄的增加而显著增加或减少。统计分析表明，有机物的含量是影响真细菌、nirK和nosZ群落丰度的最重要因素，这两个基因的拷贝数是改变真细菌群落沿着时间序列的最重要驱动因素。这项研究产生了一个初步的洞察生态的细菌携带基因的反硝化途径在一个新发展的高山环境。
Quantitative PCR of denitrification genes encoding the nitrate, nitrite, and nitrous oxide reductases was used to study denitrifiers across a glacier foreland. Environmental samples collected at different distances from a receding glacier contained amounts of 16S rRNA target molecules ranging from 4.9 X 10(5) to 8.9 X 10(5) copies per nanogram of DNA but smaller amounts of narG, nirK, and nosZ target molecules. Thus, numbers of narG, nirK, nirS, and nosZ copies per nanogram of DNA ranged from 2.1 X 10(3) to 2.6 X 10(4), 7.4 x 10(2) to 1.4 X 10(3), 2.5 X 10(2) to 6.4 X 10(3), and 1.2 X 10(3) to 5.5 X 10(3), respectively. The densities of 16S rRNA genes per gram of soil increased with progressing soil development. The densities as well as relative abundances of different denitrification genes provide evidence that different denitrifier communities develop under primary succession: higher percentages of narG and nirS versus 16S rRNA genes were observed in the early stage of primary succession, while the percentages of nirK and nosZ genes showed no significant increase or decrease with soil age. Statistical analyses revealed that the amount of organic substances was the most important factor in the abundance of eubacteria as well as of nirK and nosZ communities, and copy numbers of these two genes were the most important drivers changing the denitrifying community along the chronosequence. This study yields an initial insight into the ecology of bacteria carrying genes for the denitrification pathway in a newly developing alpine environment.