Sulfur respiration in a marine chemolithoautotrophic beggiatoa strain.
Sulfur respiration in a marine chemolithoautotrophic beggiatoa strain.
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DOI：
10.3389/fmicb.2011.00276
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发表时间：
2011
影响因子：
5.2
通讯作者：
Schulz-Vogt HN
中科院分区：
文献类型：
--
作者：
Schwedt A;Kreutzmann AC;Polerecky L;Schulz-Vogt HN
化石型自养菌株Beggiatoa sp.35Flor在高硫化物通量的梯度介质中培养时表现出不寻常的迁移行为。与Beggiatoa spp.一样，细丝在氧-硫化物界面形成垫子。然而，随着培养时间的延长，一个亚群积极地向下迁移到介质的缺氧和硫化部分，在那里细丝的硫磺和聚羟基烷酸(PHA)包裹体逐渐枯竭。这种消耗与硫化氢的产生有关。耗尽硫磺和PHA的细丝返回到氧-硫化物界面，在那里它们通过好氧硫化物氧化切换回沉积硫磺和PHA。基于这些观察，我们得出结论，在缺氧条件下，内部储存的元素硫是以牺牲储存的PHA为代价进行呼吸的。到目前为止，硝酸盐一直被认为是化学自养Beggiatoma spp的替代电子受体。在缺氧条件下。由于基质和花丝中不含氧化氮化合物，我们可以排除这种代谢。此外，到目前为止，在缺氧条件下，硫磺与PHA的呼吸作用仅被描述为异养Beggiatoa spp.，但我们的培养基中不含可接近的有机碳。因此，PHA包裹体必须来自大气中的CO2，在氧-硫化物界面上被灯丝固定。我们认为，将细丝定向迁移到氧-硫化物梯度系统的缺氧区是保持细胞完整性的最后手段，否则在存在氧气和高硫化物通量的情况下，细胞完整性将受到过度硫沉积的影响。这种迁移的调控机制尚不清楚。
The chemolithoautotrophic strain Beggiatoa sp. 35Flor shows an unusual migration behavior when cultivated in a gradient medium under high sulfide fluxes. As common for Beggiatoa spp., the filaments form a mat at the oxygen–sulfide interface. However, upon prolonged incubation, a subpopulation migrates actively downward into the anoxic and sulfidic section of the medium, where the filaments become gradually depleted in their sulfur and polyhydroxyalkanoates (PHA) inclusions. This depletion is correlated with the production of hydrogen sulfide. The sulfur- and PHA-depleted filaments return to the oxygen–sulfide interface, where they switch back to depositing sulfur and PHA by aerobic sulfide oxidation. Based on these observations we conclude that internally stored elemental sulfur is respired at the expense of stored PHA under anoxic conditions. Until now, nitrate has always been assumed to be the alternative electron acceptor in chemolithoautotrophic Beggiatoa spp. under anoxic conditions. As the medium and the filaments were free of oxidized nitrogen compounds we can exclude this metabolism. Furthermore, sulfur respiration with PHA under anoxic conditions has so far only been described for heterotrophic Beggiatoa spp., but our medium did not contain accessible organic carbon. Hence the PHA inclusions must originate from atmospheric CO2 fixed by the filaments while at the oxygen–sulfide interface. We propose that the directed migration of filaments into the anoxic section of an oxygen–sulfide gradient system is used as a last resort to preserve cell integrity, which would otherwise be compromised by excessive sulfur deposition occurring in the presence of oxygen and high sulfide fluxes. The regulating mechanism of this migration is still unknown.
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影响因子：
64.8
作者：
FOSSING, H;GALLARDO, VA;ULLOA, O
通讯作者：
ULLOA, O
影响因子：
3.6
作者：
Kamp, Anja;Roy, Hans;Schulz-Vogt, Heide N.
通讯作者：
Schulz-Vogt, Heide N.
影响因子：
3.8
作者：
Kamyshny, Alexey, Jr.;Borkenstein, Clemens G.;Ferdelman, Timothy G.
通讯作者：
Ferdelman, Timothy G.
影响因子：
4.4
作者：
Kalanetra, KM;Huston, SL;Nelson, DC
通讯作者：
Nelson, DC
影响因子：
3.2
作者：
FAUST, L;WOLFE, RS
通讯作者：
WOLFE, RS