Konishi Yasuhiro, Tsukiyama Takeshi, Saitoh Norizoh, Nomura Toshiyuki, Nagamine Shinsuke, Takahashi Yoshio, Uruga Tomoya
Department of Chemical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan.
J Biosci Bioeng. 2007 Jun;103(6):568-71. doi: 10.1263/jbb.103.568.
X-ray absorption near-edge structure spectroscopy (XANES) was successfully employed to determine the gold valence in the metal-reducing bacterium Shewanella algae after exposure to a 1 mM aqueous HAuCl4 solution for 10-120 min. XANES spectra revealed the oxidation state of gold in the bacterial cells to be Au(0) without any contribution from Au(III), demonstrating that S. algae cells can reduce AuCl4- ions to elemental gold. Transmission electron microscopy (TEM) and energy dispersive X-ray (EDX) analysis confirmed that gold nanoparticles 5-15 nm in size were deposited in the periplasmic space of the bacterial cells; a preferable, cell surface location for the easy recovery of biogenic nanoparticles.
利用X射线吸收近边结构光谱法（XANES）成功测定了金属还原菌嗜盐碱单胞菌（Shewanella algae）在暴露于1 mM HAuCl4水溶液10 - 120分钟后的金价态。XANES光谱显示细菌细胞中的金氧化态为Au(0)，没有Au(III)的贡献，这表明嗜盐碱单胞菌细胞可以将AuCl4-离子还原为元素金。透射电子显微镜（TEM）和能量色散X射线（EDX）分析证实，尺寸为5 - 15 nm的金纳米颗粒沉积在细菌细胞的周质空间中；这是生物源纳米颗粒易于回收的理想细胞表面位置。
