...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Crystal growth & design >Controlling Biomineralization: The Effect of Solution Composition on Coccolith Polysaccharide Functionality
【24h】

Controlling Biomineralization: The Effect of Solution Composition on Coccolith Polysaccharide Functionality

机译：控制生物矿化：溶液组成对球藻多糖功能的影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The calcite shields produced by unicellular marine algae demonstrate the remarkable crystal control that organisms can achieve through biomineralization. Emiliania huxleyi produces complex polysaccharides ("coccolith associated polysaccharides", CAP) that regulate crystal morphology by preferentially attaching to calcite acute step edges, thus promoting growth of the specific crystal faces required for design of that species of coccolith. However, to control crystal growth, the alga must be able to control CAP behavior at the local scale, so its functionality can be switched on and off. Here, we show that the functionality of CAP from E. huxleyi depends directly on solution composition. We used atomic force microscopy (AFM) to investigate the behavior of calcite surfaces under varying pH, in the presence of CAP and cations chosen to test the role of ionic potential, that is, charge per unit radius (K+, Na+, Sr+, Ca2+, Mg2+, Zn2+, and Eu3+ at 1 M charge concentration). Site-specific adsorption to calcite steps, essential for regulating morphology, only occurs in neutral to acidic pH (range investigated: 3.4-7.7) and in the presence of K+, Na+, Sr2+, and Ca2+. Basic pH (range investigated: 9.9-11.3), or cations of higher ionic potential than Ca (Mg2+, Zn2+, and Eu3+), caused CAP to ignore step edges, turning off its normal functionality. We propose that complexation between cations, CAP, and the calcite surface controls CAP behavior. Thus, cations provide an on/off switch for CAP function, with the power to regulate and disturb coccolith biomineralization as well as to control calcite growth at the unblocked precipitation sites.
机译：单细胞海藻产生的方解石防护层显示出生物体可通过生物矿化实现的卓越晶体控制。 Emiliania huxleyi产生复杂的多糖（“ cococolith结合的多糖”，CAP），该多糖通过优先附着在方解石尖锐的台阶边缘来调节晶体形态，从而促进了该coccolith物种设计所需的特定晶面的生长。但是，要控制晶体的生长，藻类必须能够在局部规模上控制CAP行为，因此可以打开和关闭其功能。在这里，我们证明了赫氏大肠杆菌中CAP的功能直接取决于解决方案的组成。我们使用原子力显微镜（AFM）在存在CAP和阳离子的情况下研究了方解石表面在不同pH值下的行为，这些阳离子和阳离子被选择用于测试离子势的作用，即每单位半径的电荷（K +，Na +，Sr +，Ca2 + ，Mg2 +，Zn2 +和Eu3 +（电荷浓度为1 M）。方解石步骤的位点特异性吸附是调节形态所必需的，仅在中性至酸性pH值（研究范围：3.4-7.7）中以及在K +，Na +，Sr2 +和Ca2 +的存在下发生。碱性pH值（研究范围：9.9-11.3）或比Ca（Mg2 +，Zn2 +和Eu3 +）高的离子电势导致CAP忽略台阶边缘，从而关闭了其正常功能。我们建议阳离子，CAP和方解石表面之间的络合物控制CAP行为。因此，阳离子提供了用于CAP功能的开/关开关，具有调节和扰乱可可石矿化以及控制方解石在未阻塞沉淀部位生长的能力。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号