Miller Scott R, Bebout Brad M
NASA Ames Research Center, Moffett Field, California 94035, USA.
Appl Environ Microbiol. 2004 Feb;70(2):736-44. doi: 10.1128/AEM.70.2.736-744.2004.
Physiological and molecular phylogenetic approaches were used to investigate variation among 12 cyanobacterial strains in their tolerance of sulfide, an inhibitor of oxygenic photosynthesis. Cyanobacteria from sulfidic habitats were found to be phylogenetically diverse and exhibited an approximately 50-fold variation in photosystem II performance in the presence of sulfide. Whereas the degree of tolerance was positively correlated with sulfide levels in the environment, a strain's phenotype could not be predicted from the tolerance of its closest relatives. These observations suggest that sulfide tolerance is a dynamic trait primarily shaped by environmental variation. Despite differences in absolute tolerance, similarities among strains in the effects of sulfide on chlorophyll fluorescence induction indicated a common mode of toxicity. Based on similarities with treatments known to disrupt the oxygen-evolving complex, it was concluded that sulfide toxicity resulted from inhibition of the donor side of photosystem II.
采用生理和分子系统发育方法，研究了12株蓝藻菌株对硫化物（一种光合放氧抑制剂）耐受性的差异。研究发现，来自含硫环境的蓝藻在系统发育上具有多样性，并且在存在硫化物的情况下，其光系统II性能表现出约50倍的差异。虽然耐受性程度与环境中的硫化物水平呈正相关，但无法根据菌株近亲的耐受性来预测其表型。这些观察结果表明，硫化物耐受性是一种主要受环境变化影响的动态特性。尽管绝对耐受性存在差异，但硫化物对叶绿素荧光诱导影响方面菌株之间的相似性表明存在共同的毒性模式。基于与已知会破坏放氧复合体的处理方法的相似性，得出结论：硫化物毒性是由光系统II供体侧的抑制作用导致的。
