Kim Tae Gwan, Yi Taewoo, Lee Jung-Hee, Cho Kyung-Suk
J Environ Biol. 2015 Mar;36(2):371-5.
To investigate starvation effect on methanogen community, two identical membrane reactors were continuously operated for 84 consecutive days, with a temperature change from 50 degrees C to 20 degrees C. Continuous feeding washed out 97% biomass from reactors during the experimental period. Quantitative PCR, using mcrA genes, indicated that the methanogen abundance decreased from 7.0 x 10(7) to 1.2 x 10(7) mcrA copies ml(-1) (volume basis) at 50 degrees C, and then increased to 4.4 x 10(7) mcrA copies ml(7) at 20 degrees C (p<0.05). Correspondence analysis indicated that methanogen communities were distinctly grouped by each temperature. Canonical correspondence analysis indicated that temperature showed a significant correlation with the methanogen community composition. These results suggest that methanogens can survive for a long time (at least more than 84 days) under starvation conditions, and that temperature could be a primary factor determining the density and community of methanogens.
为研究饥饿对产甲烷菌群落的影响，两个相同的膜生物反应器连续运行84天，温度从50℃降至20℃。在实验期间，连续进料使反应器中97%的生物质被冲洗掉。使用mcrA基因的定量PCR结果表明，产甲烷菌丰度在50℃时从7.0×10⁷ mcrA拷贝·ml⁻¹（基于体积）降至1.2×10⁷ mcrA拷贝·ml⁻¹，然后在20℃时增至4.4×10⁷ mcrA拷贝·ml⁻¹（p<0.05）。对应分析表明，产甲烷菌群落按每个温度明显分组。典范对应分析表明，温度与产甲烷菌群落组成显著相关。这些结果表明，产甲烷菌在饥饿条件下可长期存活（至少超过84天），且温度可能是决定产甲烷菌密度和群落的主要因素。
