ANOXYGENIC MICROBIAL MATS OF HOT-SPRINGS - THERMOPHILIC CHLOROBIUM SP
ANOXYGENIC MICROBIAL MATS OF HOT-SPRINGS - THERMOPHILIC CHLOROBIUM SP
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DOI：
10.1111/j.1574-6968.1990.tb04079.x
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发表时间：
1990-12-15
影响因子：
4.2
通讯作者：
JORGENSON, BB
中科院分区：
文献类型：
--
作者：
CASTENHOLZ, RW;BAULD, J;JORGENSON, BB
非层压，绿色至黄绿色微生物垫，与Chlorobium sp.作为唯一的光养生物，发生在55至约40摄氏度的温泉和附近的罗托鲁瓦，新西兰。pH值范围为4.3至6.2，硫化物为0.2至1.8 mM。这种Chlorobium sp.在高达55 ℃的温度下形成种群的能力是独一无二的。使用光纤微探针对完整的绿球藻团进行光谱放射性测量，结果显示出很大的不透明度，在垫内0.7 mm深度处可获得不到0.1%的入射辐射（在光合作用可用波长下），尽管浓缩的绿球藻种群有时会延伸到3毫米深度。硫化物依赖性，缺氧光合作用表现为[C-14]碳酸氢盐同化垫悬浮液和完整的垫由硫化物特定的微电极。没有发生氧气析出，并且在垫内不存在O2。光增强摄取的[C-14]乙酸也发生在细胞悬浮液。这一比率没有提高硫化物。
Non-laminated, green to yellow-green microbial mats, with Chlorobium sp. as the only phototroph, occurred from 55 to about 40-degrees-C in hot springs in and near Rotorua, New Zealand. The pH ranged from 4.3 to 6.2 and sulfide from 0.2 to 1.8 mM. This Chlorobium sp. is unique in its ability to form populations at temperatures as high as 55-degrees-C. Spectroradiometric measurements with a fiber-optic microprobe in the intact chlorobium mass showed great opacity with less than 0.1% of the incident radiation (at photosynthetically usable wavelengths) available at 0.7 mm depth within the mat, although the concentrated Chlorobium population sometimes extended to 3 mm depth. Sulfide-dependent, anoxygenic photosynthesis was demonstrated by [C-14]bicarbonate assimilation in mat suspensions and in intact mats by a sulfide-specific microelectrode. No oxygen evolution occurred and no O2 was present within the mat. A light-enhanced uptake of [C-14]acetate also occurred in cell suspensions. This rate was not enhanced by sulfide.