ナノスケールでミネラルフェーズを新鮮なナクレに変換する
Ross T DeVol1, Chang-Yu Sun1, Matthew A Marcus2
1Department of Physics, University of Wisconsin-Madison , 1150 University Avenue, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|September 26, 2015
まとめ
研究者達は 赤いアボロン・ナクレに 無形なカルシウム炭酸 (ACC) の前駆物質を直接観察しました これらのACC段階は,予想されるアラゴニットではなく,カルシットを形成する軟体殻に意外と似ている.
科学分野:
- バイオミネラライゼーションの研究
- 材料科学
- 海洋生物学
背景:
- 貝殻に不可欠なバイオミネラル化合物です 貝殻に不可欠な生物化合物です
- バイオミネラライゼーションには,しばしば一時的な無形カルシウム炭酸 (ACC) の前体が含まれます.
- ナクレ形成におけるACC前駆体は直接観察することが困難である.
研究 の 目的:
- カルシウム炭酸 (ACC) の無形前駆体をガストロポッドナクレで直接観察し,特徴づけること.
- 観察されたACC相を他のバイオミネラル化プロセスで見つかったものと比較する.
- 結晶形成の経路を調査する
主な方法:
- シンクロトロンスペクトル顕微鏡を用いて,赤アボロン (Haliotis rufescens) の殻のナクレの成長面を分析した.
- ナクレの形成部位における前駆体相の直接観察
- 観察された無形カルシウム炭酸相の化学的および構造的分析.
主要な成果:
- ガストロポッドのナクレア形成における無形カルシウム炭酸 (ACC) 前駆体に関する最初の直接的な観察が提示される.
- 観察されたアボロンナクレのACC相は,以前,海のでカルシット形成の前駆体として特定されたものと同一である.
- これらの発見は,アラゴニットナクレの予想された原アラゴニットまたは低結晶アラゴニット (pAra) と対照的です. pAraはサンゴに観察されました.
結論:
- ACC前駆体の直接観察は,ナクレア生物鉱物化の既存のモデルに挑戦しています.
- 予期せぬACC相の類似性は,異なるバイオミネラル構造の間の前駆体経路が保存されていることを示唆している.
- ナクレア形成とその性質を制御するための影響を理解するには,さらなる研究が必要である.
関連する概念動画
Nuclear Transmutation
Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed protons being...
Metabolism of Chemolithotrophs
Chemolithotrophs are microorganisms that obtain energy by oxidizing inorganic molecules such as hydrogen gas (H₂), ammonia (NH₃), reduced sulfur compounds (H₂S, S²⁻), and ferrous iron (Fe²⁺). Unlike heterotrophic organisms that rely on organic carbon, chemolithotrophs transfer electrons from these inorganic donors to the electron transport chain (ETC), generating a proton motive force (PMF) that drives ATP synthesis through oxidative phosphorylation. However, because inorganic electron donors...
Microbes and Other Elemental Cycles
Microbial activity plays a pivotal role in the biogeochemical cycling of iron and manganese, especially at the redox gradients characteristic of stratified aquatic environments. These cycles are driven by microbial transformations between oxidized and reduced forms of the metals, allowing organisms to exploit them for metabolic energy and structural purposes.Iron Cycling Across Redox GradientsIn neutral, oxygen-rich surface waters, iron is predominantly found in its oxidized, insoluble ferric...
Microbial Bioremediation of Uranium
Microorganisms play a critical role in the transformation and immobilization of uranium in contaminated environments through four main pathways: bioreduction, biosorption, bioaccumulation, and biomineralization. These mechanisms reduce uranium’s toxicity and prevent its migration through groundwater systems, offering sustainable approaches for in situ bioremediation.Bioreduction of UraniumBioreduction is driven by anaerobic bacteria such as certain strains of Geobacter and Shewanella, which use...
Microbial Leaching
Microbial leaching, also known as bioleaching, is an environmentally favorable method for extracting metals from low-grade ores using specific microorganisms. This biotechnological approach is particularly valuable for mining operations targeting copper, gold, and uranium, where traditional extraction methods may be economically or environmentally impractical.Copper Leaching and Microbial CatalysisIn copper bioleaching, crushed ore is arranged into heaps and irrigated with a dilute sulfuric...
Microbial Corrosion
Microbiologically Influenced Corrosion (MIC) is a significant form of material degradation caused by the metabolic activities of microorganisms. This phenomenon poses substantial challenges across various industries, including oil and gas, maritime, and water treatment sectors.MIC occurs when microorganisms, such as bacteria, archaea, and fungi, colonize metal surfaces, forming biofilms that alter the local electrochemical environment. These biofilms can lead to the production of corrosive...


