在珊瑚骨架形成过程中更快的结晶与海洋酸化的弹性相关
Connor A Schmidt1, Cayla A Stifler1, Emily L Luffey1
1Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|January 17, 2022
概括
珊瑚骨是由细胞内囊泡产生的无形碳酸颗粒形成的,而不是开放的海水. 这种细胞内过程影响了骨结晶率,解释了珊瑚对海洋酸化的不同弹性.
科学领域:
- 海洋生物学
- 生物矿物化
- 斯克拉克提尼珊瑚
背景情况:
- 硬珊瑚骨主要是阿拉贡石 (CaCO3).
- 生物矿化过程涉及无形碳酸前体.
- 之前的假设将化放在细胞外化液 (ECF) 中.
研究的目的:
- 在珊瑚骨架形成过程中调查无形碳酸颗粒的位置和性质.
- 要确定粒子形成是否发生在细胞内或细胞外.
- 将颗粒形成和骨结晶与珊瑚对海洋酸化 (OA) 的敏感性相关.
主要方法:
- 在三种珊瑚属的无形颗粒形成的微观观测:Acropora sp.,Stylophora pistillata和Turbinaria peltata.
- 对粒子大小和组成的分析,重点是无形前体相.
- 测量无形表面层厚度和与属性特定的OA敏感度的相关性.
主要成果:
- 在细胞内囊泡中经常观察到无形碳酸颗粒 (0.21.0μm),而不是ECF.
- 这些细胞内粒子是骨添加剂制造的主要来源.
- 骨表面结晶率有很大差异,阿克罗波拉的结晶速度较慢,无形层较厚,与OA脆弱性相关.
结论:
- 珊瑚骨是通过囊泡内的细胞内粒子沉形成的, 挑战了以前的细胞外模型.
- 细胞内化会影响骨特性和对海洋酸化的差异性反应.
- 在Acropora骨中较慢的结晶解释了它们对OA的敏感性增加,而在Stylophora中更快的结晶表明了弹性.
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