BACTERIAL ASSOCIATIONS WITH MARINE OSCILLATORIA SP. (TRICHODESMIUM SP.) POPULATIONS: ECOPHYSIOLOGICAL IMPLICATIONS 1
BACTERIAL ASSOCIATIONS WITH MARINE OSCILLATORIA SP. (TRICHODESMIUM SP.) POPULATIONS: ECOPHYSIOLOGICAL IMPLICATIONS 1
复制标题
与海洋振荡菌 SP 的细菌关联。
DOI：
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发表时间：
1989
期刊：
影响因子：
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通讯作者：
L. Prufert
中科院分区：
文献类型：
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作者：
Hans W. Paerly;B. Bebout;L. Prufert
在三个不同的场合，我们调查了细菌协会的形态和生理方面与无处不在的海洋N2固定蓝藻Trichodesmium sp.紧密的协会一般特点Trichodesmium水华的聚集体;协会是在白天和晚上的时间。棒状和丝状异养细菌的定殖发生在活跃固定N2（乙炔还原）的Trichodesmiun聚集体上。扫描电子显微镜和光学显微镜显示细菌位于周围和聚集体内。显微放射自显影表明，相关细菌主要介导利用微量添加的3 H标记的碳水化合物（果糖，葡萄糖，甘露醇）和氨基酸，而束毛藻仅利用氨基酸。使用微电极进行的氧气测量显示，聚集体中的局部氧气消耗很高，在从光合光照期过渡到黑暗期后，氧气从过饱和迅速（一分钟内）变化到不饱和。刺培养技术证实了聚集体相关细菌中存在异养N2固定剂。平行部署的氧微电极，四氮唑盐2，3，5三苯基四氮唑氯化物（TTC）和乙炔还原试验证明微需氧的要求，培养的细菌之间的固氮酶活性的表达。
On three separate occasions we investigated morphological and physiological aspects of bacterial associations with planktonic aggregates of the ubiquitous marine N2 fixing cyanobacterium Trichodesmium sp. Close associations generally characterized Trichodesmium blooms; associations were present during day‐ and night‐time. Colonization by both rod‐shaped and filamentous heterotrophic bacteria occurred on Trichodesmiun aggregates actively fixing N2 (acetylene reduction). Scanning electron and optical microscopy showed bacteria located both around and within aggregates. Microautoradiography demonstrated that associated bacteria largely mediated utilization of trace additions of 3H‐labeled carbohydrates (fructose, glucose, mannitol) and amino acids, whereas Trichodesmium utilized amino acids only. Oxygen measurements using microelectrodes revealed high localized oxygen consumption among aggregates, with rapid (within a minute) changes from supersaturated to subsaturated oxygen following the transition from photosynthetic illuminated to dark periods. Stab culturing techniques confirmed the presence of heterotrophic N2 fixers among aggregate‐associated bacteria. Parallel deployment of oxygen microelectrodes, the tetrazolium salt 2,3,5 triphenyl tetrazolium chloride (TTC) and acetylene reduction assays demonstrated microaerophilic requirements for expression of nitrogenase activity among cultured bacteria.