Growth temperatures of archaeal communities can be estimated from the guanine-plus-cytosine contents of 16S rRNA gene fragments
Growth temperatures of archaeal communities can be estimated from the guanine-plus-cytosine contents of 16S rRNA gene fragments
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DOI：
10.1111/1758-2229.12035
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发表时间：
2013-06-01
影响因子：
3.3
通讯作者：
Ishibashi, Jun-Ichiro
中科院分区：
文献类型：
--
作者：
Kimura, Hiroyuki;Mori, Kousuke;Ishibashi, Jun-Ichiro
环境样品中的原核生物生长温度很难测量，因为很难在自然环境中培养有活力的原核生物。本研究全面调查了原核生物的生长温度和16SrRNA序列，并根据16SrRNA序列中鸟嘌呤加胞嘧啶含量（PGC）估算了原核生物的生长温度。我们把重点放在古细菌上，因为这个群体的生长温度范围很广。它们的最低（Tmin），最佳（Topt）和最高（Tmax）的生长温度与其16S rRNA基因的PGC强烈相关。建立线性回归方程，以近似PGC的Tmin、Topt和Tmax。我们还建立了一个线性回归方程计算PGC的16S rRNA基因的基础上的PCR片段的熔解温度（Tm），而不使用克隆文库或测序。环境样品从各种各样的微生物自然栖息地获得。实时荧光PCR扩增古细菌16S rRNA基因，熔解曲线分析测定其Tm值。根据这些值，使用线性回归方程计算16S rRNA基因的PGC和平均Tmin、Topt和Tmax。这些温度与原位温度密切相关。Tmax与这些温度特别一致，这表明许多古生菌生活在最高生长温度下。
Prokaryote growth temperatures in environmental samples are difficult to measure because it is hard to culture viable prokaryotes in natural environments. We comprehensively surveyed growth temperatures and 16S rRNA sequences of prokaryotes to estimate their growth temperatures based on guanine-plus-cytosine contents (PGC) of their 16S rRNA sequences. We focused on archaea because of the wide range of growth temperatures within this group. Their minimum (Tmin), optimum (Topt) and maximum (Tmax) growth temperatures correlated strongly with PGC of their 16S rRNA genes. Linear regression equations were established to approximate Tmin, Topt and Tmax from PGC. We also established a linear regression equation for calculating PGC of 16S rRNA genes based on the melting temperatures (Tm) of PCR fragments, without using a clone library or sequencing. Environmental samples were obtained from a wide variety of microbial natural habitats. Tm of archaeal 16S rRNA genes amplified by real-time PCR were determined by melting curve analysis. Based on those values, PGC of 16S rRNA genes and mean Tmin, Topt and Tmax were calculated using the linear regression equations. These temperatures correlated strongly with the in situ temperatures. Tmax agreed particularly well with these temperatures, suggesting many archaea live at their maximum growth temperatures.