Molecular level characterization of diatom‐associated biopolymers that bind 234Th, 233Pa, 210Pb, and 7Be in seawater: A case study with Phaeodactylum tricornutum
Molecular level characterization of diatom‐associated biopolymers that bind 234Th, 233Pa, 210Pb, and 7Be in seawater: A case study with Phaeodactylum tricornutum
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海水中结合 234Th、233Pa、210Pb 和 7Be 的硅藻相关生物聚合物的分子水平表征：以三角褐指藻为例
DOI：
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
D. Schumann
中科院分区：
文献类型：
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作者：
C. Chuang;P. Santschi;Chen Xu;Yuelu Jiang;Y. Ho;A. Quigg;Laodong Guo;P. Hatcher;M. Ayranov;D. Schumann
为了研究生物硅相关的生物聚合物对放射性核素的清除的重要性，硅藻Phaeodactylum tricornutum与放射性核素234 Th，233 Pa，210 Pb，和7 Be在其生长阶段一起孵育。确定与不同有机化合物类别结合的放射性核素的归一化亲和力系数（即，蛋白质、总碳水化合物、糖醛酸）、细胞内（乙二胺四乙酸和十二烷基硫酸钠可提取物）和硅藻壳包埋的生物聚合物级分（BF）。结果表明，放射性核素主要富集在硅藻壳BF中。在三个测量的有机成分，糖醛酸表现出最强的亲和力，所有测试的放射性核素。通过分光光度法和二维异质单量子相干-核磁共振分析证实，硅藻壳BF主要由富含羧基的脂肪族磷蛋白组成，这可能是许多放射性核素强结合的原因。这项研究的结果为不同种类的硅藻相关生物聚合物选择性吸收放射性核素提供了证据，这些生物聚合物共同发挥作用，而不是作为单一化合物。这清楚地表明了这些硅藻相关的生物聚合物，特别是硅藻生物聚合物，在清除和分馏海洋中用作颗粒示踪剂的放射性核素方面的重要性。
In order to investigate the importance of biogenic silica associated biopolymers on the scavenging of radionuclides, the diatom Phaeodactylum tricornutum was incubated together with the radionuclides 234Th, 233Pa, 210Pb, and 7Be during their growth phase. Normalized affinity coefficients were determined for the radionuclides bound with different organic compound classes (i.e., proteins, total carbohydrates, uronic acids) in extracellular (nonattached and attached exopolymeric substances), intracellular (ethylene diamine tetraacetic acid and sodium dodecyl sulfate extractable), and frustule embedded biopolymeric fractions (BF). Results indicated that radionuclides were mostly concentrated in frustule BF. Among three measured organic components, Uronic acids showed the strongest affinities to all tested radionuclides. Confirmed by spectrophotometry and two‐dimensional heteronuclear single quantum coherence‐nuclear magnetic resonance analyses, the frustule BF were mainly composed of carboxyl‐rich, aliphatic‐phosphoproteins, which were likely responsible for the strong binding of many of the radionuclides. Results from this study provide evidence for selective absorption of radionuclides with different kinds of diatom‐associated biopolymers acting in concert rather than as a single compound. This clearly indicates the importance of these diatom‐related biopolymers, especially frustule biopolymers, in the scavenging and fractionation of radionuclides used as particle tracers in the ocean.
影响因子：
2.9
作者：
Abdullahi, AS;Underwood, GJC;Gretz, MR
通讯作者：
Gretz, MR