2013 Fiscal Year Final Research Report

Synthesis of functional metal nano particles based on bacterial metal metabolism

Research Project

Project/Area Number	23658078
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Multi-year Fund
Research Field	Applied microbiology
Research Institution	Kyoto University
Principal Investigator	KAWAMOTO Jun 京都大学, 化学研究所, 助教 (90511238)
Project Period (FY)	2011 – 2012
Keywords	応用微生物学 / 微生物機能 / 環境農学 / 金属ナノ粒子
Research Abstract	Metallic nanoparticles have huge potentials in nanotechnology. In this study, we attempted to develop the novel methods for metallic nanoparticles by using microorganisms. We have isolated a novel strain of Pseudomonas species, which produces nano-sized silver particles in the presence of silver nitrate at moderate temperatures, suggesting that this strain has an unique mechanism for metallic nanoparticle synthesis. In order to develop the efficient nano particle synthesis, we also analyzed the iron-respiratory mechanism of a psychrotrophic bacterium, Shewanella livingstonensis Ac10, which has flexible metal respiratory system at anaerobic conditions. Only when grown with divalent iron (ferric citrate), this strain produces a homolog of a phosphate selective porn, PhoE. In the presence of ferric citrate, a gene-disrupted mutant of phoE showed growth retardation, indicating that PhoE has an important role in iron-respiration mechanism of this strain.