Sclerite formation in the hydrothermal-vent "scaly-foot" gastropod - possible control of iron sulfide biomineralization by the animal
Sclerite formation in the hydrothermal-vent "scaly-foot" gastropod - possible control of iron sulfide biomineralization by the animal
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DOI：
10.1016/j.epsl.2005.11.029
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发表时间：
2006-02-15
影响因子：
5.3
通讯作者：
Kirschvink, JL
中科院分区：
文献类型：
--
作者：
Suzuki, Y;Kopp, RE;Kirschvink, JL
在印度洋罗德里格斯三重交界处的深海热液区发现了一种腹足类动物，它有鳞片状的结构，被称为硬化剂，它的脚上有硫化铁矿化。目前还不知道其他生物能产生由硫化铁组成的骨架。为了研究铁硫化物矿化是否由腹足动物介导的硬膜功能，我们进行了详细的物理和化学表征。硫化铁硬结石的纳米结构表征表明，硫化铁矿物黄铁矿（FeS2）和灰长铁矿（Fe3S4）分别以独特的晶体习性在有机基质内外形成。硬晶石的磁性能与纳米结构特征预测的磁性能基本一致，但并没有对磁接受进行优化，而是支持磁性矿物作为结构元素的使用。其力学性能优于其他生物矿物，在喷口环境中用于捕食和防止捕食。这些特征以及短爪蟹的共存，支持了这样的推论：硫化铁的矿化可能是由腹足类动物控制的，以使硬壳变硬，以保护自己免受捕食者的攻击。硫和铁同位素分析表明，岩屑中的硫和铁来自热液流体，而不是细菌代谢物，铁的供应不太可能由腹足动物调节，以实现硫化铁矿化。我们认为腹足类动物可能通过调节体内还原性硫化合物的浓度来控制硫化铁矿化。(c) 2005 Elsevier B.V.版权所有
A gastropod from a deep-sea hydrothermal field at the Rodriguez triple junction, Indian Ocean, has scale-shaped structures, called sclerites, mineralized with iron sulfides in its foot. No other organisms are known to produce a skeleton consisting of iron sulfides. To investigate whether iron Sulfide mineralization is mediated by the gastropod for the function of the sclerites, we performed a detailed physical and chemical characterization. Nanostructural characterization of the iron sulfide sclerites reveals that the iron sulfide minerals pyrite (FeS2) and greigite (Fe3S4) form with unique crystal habits inside and outside of the organic matrix, respectively. The magnetic properties of the sclerites, which are mostly consistent with those predicted from their nanostructual features, are not optimized for magnetoreception and instead support use of the magnetic minerals as structural elements. The mechanical performance of the sclerites is superior to that of other biominerals used in the vent environment for predation as well as protection from predation. These characteristics, as well as the co-currence of brachuran crabs, support the inference that the mineralization of iron sulfides might be controlled by the gastropod to harden the sclerites for protection from predators. Sulfur and iron isotopic analyses indicate that sulfur and iron in the sclerites originate from hydrothermal fluids rather than from bacterial metabolites, and that iron supply is unlikely to be regulated by the gastropod for iron sulfide mineralization. We propose that the gastropod may control iron sulfide mineralization by modulating the internal concentrations of reduced sulfur compounds. (c) 2005 Elsevier B.V. All rights reserved.