據(jù)9月份Microbiology雜志上的一篇文章,，科學(xué)家發(fā)現(xiàn)一種微生物能夠快速將工業(yè)金屬廢料轉(zhuǎn)變成高價值的催化劑進而用于清潔能源的生產(chǎn),。
據(jù)文章報道，伯明翰大學(xué)的研究人員發(fā)現(xiàn)了一種新機制,，其允許土壤中的常見細菌Desulfovibrio desulfuricans重新從工業(yè)廢料中獲得稀有金屬鈀,。
鈀是鉑族金屬（PGMs）中的一種，由于其具有優(yōu)越的化學(xué)性能而得到廣泛使用,。PGMs一般使用于催化系統(tǒng)中,，是自我催化轉(zhuǎn)換器的活性成分，該轉(zhuǎn)換機制能夠降低溫室氣體排放,。
Kevin Deplanche博士主持了這項研究,，同時他也解釋了這種再生PGMs新技術(shù)的必要性,。他表示，一方面這些金屬是稀有資源,，這點可以從它們在市場中的高價值體現(xiàn)出來,。此外，在過去的10年,，這些金屬也一直是供少于求,。因此研究再生鈀的方法對于保證未來這些資源的利用是很重要的，也是很有必要的,。
先前的研究表明,，Desulfovibrio desulfuricans能夠減少工業(yè)金屬廢料中的鈀。目前科學(xué)家已經(jīng)識別出了參與該過程的小分子,。位于細菌膜表面的氫化酶參與鈀的再生,。包裹著鈀微粒的細菌細胞科學(xué)家稱之為’BioPd’。
研究人員相信BioPd在清潔能源方面具有巨大的潛力,，且BioPd是清理工業(yè)污染物質(zhì)的極好催化劑,，比如鉻。另外BioPd甚至能夠用于產(chǎn)生清潔的電能,。研究人員表示,，他們的最終目的是開發(fā)一種簡便的技術(shù)將工業(yè)廢料轉(zhuǎn)化成高價值催化劑以進行綠色能源的生產(chǎn)。
更多閱讀：
Nature：細菌產(chǎn)生抗藥性的機制
PNAS：一些慢性疲勞綜合征患者身上發(fā)現(xiàn)的病毒
Nature：細菌鞭毛改變轉(zhuǎn)動方向的本領(lǐng)
Biotechnology Journal：細菌也有“嗅覺”
Microbiology：藍色鏈霉菌中篩選出活性基因簇
生物谷推薦原文出處：
Microbiology, DOI: 10.1099/mic.0.036681-0
Involvement of hydrogenases in the formation of highly catalytic Pd(0) nanoparticles by bioreduction of Pd(II) using Escherichia coli mutant strains
Kevin Deplanche1, Isabelle Caldelari2,, Iryna P. Mikheenko1, Frank Sargent2 and Lynne E. Macaskie1
1 Unit of Functional Bionanomaterials, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
2 Division of Molecular and Environmental Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
Escherichia coli produces at least three [NiFe] hydrogenases (Hyd-1, Hyd-2 and Hyd-3). Hyd-1 and Hyd-2 are membrane-bound respiratory isoenzymes with their catalytic subunits exposed to the periplasmic side of the membrane. Hyd-3 is part of the cytoplasmically oriented formate hydrogenlyase complex. In this work the involvement of each of these hydrogenases in Pd(II) reduction under acidic (pH 2.4) conditions was studied. While all three hydrogenases could contribute to Pd(II) reduction, the presence of either periplasmic hydrogenase (Hyd-1 or Hyd-2) was required to observe Pd(II) reduction rates comparable to the parent strain. An E. coli mutant strain genetically deprived of all hydrogenase activity showed negligible Pd(II) reduction. Electron microscopy suggested that the location of the resulting Pd(0) deposits was as expected from the subcellular localization of the particular hydrogenase involved in the reduction process. Membrane separation experiments established that Pd(II) reductase activity is membrane-bound and that hydrogenases are required to initiate Pd(II) reduction. The catalytic activity of the resulting Pd(0) nanoparticles in the reduction of Cr(VI) to Cr(III) varied according to the E. coli mutant strain used for the initial bioreduction of Pd(II). Optimum Cr(VI) reduction, comparable to that observed with a commercial Pd catalyst, was observed when the bio-Pd(0) catalytic particles were prepared from a strain containing an active Hyd-1. The results are discussed in the context of economic production of novel nanometallic catalysts.
