Inhibition of Nitrosomonas europaea by Monoterpenes from Coastal Redwood (Sequoia sempervirens) in Whole-Cell Studies
Inhibition of Nitrosomonas europaea by Monoterpenes from Coastal Redwood (Sequoia sempervirens) in Whole-Cell Studies
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DOI：
10.1023/b:joec.0000006668.48855.b7
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发表时间：
2004
影响因子：
2.3
通讯作者：
Bettie Ward;K. J. Courtney;J. H. Langenheim
中科院分区：
文献类型：
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作者：
Bettie Ward;K. J. Courtney;J. H. Langenheim
抑制化感物质，包括单萜，已被认为是一个因素，在沿海红杉林中观察到的极低的硝化率。已知硝化抑制剂和一些针叶树单萜的分子结构之间的相似性已被认为是针叶树单萜抑制自养硝化菌的一个原因。利用海岸红杉针叶中含量最丰富的5种单萜类化合物，通过全细胞纯培养实验研究了单萜类化合物对亚硝化单胞菌硝化速率和生长的影响。它们是（按针叶中浓度递减的顺序）柠檬烯、α-蒎烯、桧烯、月桂烯和γ-萜品烯。5种化合物中有4种对N.欧洲分批培养实验。对两种最具抑制性的单萜类化合物柠檬烯和α-蒎烯进行了全细胞短期动力学研究，以评估这些化学物质与硝化速率之间的相互作用模式。测定了柠檬烯（38 μM）和α-蒎烯（95 μM）的抑制常数（Ki）。Lineweaver-Burk图的硝化作用在单萜类的存在下似乎适合一个非竞争性抑制模型，然而，抑制的机制可能更复杂。
Inhibition by allelochemicals, including monoterpenes, has been suggested as a factor in the extremely low nitrification rates observed in coastal redwood forests. Similarities between the molecular structure of known nitrification inhibitors and some conifer monoterpenes have been suggested as one reason for the inhibition of autotrophic nitrifiers by conifer monoterpenes. The effect of monolerpenes on nitrification rate and growth ofNitrosomonas europaeawas examined in whole-cell pure culture experiments using the five most abundant monoterpenes in coastal redwood needles. These are (in order of decreasing concentration in the needles) limonene, α-pinenc, sabinene, myrcene, and γ-terpinene. Four of the five compounds significantly inhibited growth ofN. europaeain batch culture experiments. Short-term kinetic studies of the two most inhibitory monoterpenes, limonene and α-pinene, were performed on whole cells to evaluate the mode of interaction between these chemicals and nitrification rates. Inhibition constants (Ki) of limonene (38 μM) and α-pinene (95 μM) were determined. Lineweaver-Burk plots of nitrification in the presence of monoterpenes appear to fit a noncompetitive inhibition model; however, the mechanisms of inhibition may be more complex.