許多細(xì)菌都會(huì)產(chǎn)生對(duì)人體有害的毒素,，位于英國(guó)Norwich的John Innes研究中心的科學(xué)家們對(duì)一種土壤細(xì)菌的納米生產(chǎn)機(jī)制——Tat系統(tǒng)——進(jìn)行研究,，發(fā)現(xiàn)了一種方法，能夠駕馭細(xì)菌分泌的過(guò)程來(lái)制造藥劑,。他們的結(jié)果發(fā)表在11月7日的《PNAS》上,。
??科學(xué)家們通過(guò)對(duì)Tat系統(tǒng)的研究，發(fā)現(xiàn)這個(gè)系統(tǒng)使用的蛋白質(zhì)種類(lèi)要比想象的多,。
??現(xiàn)在的生物技術(shù)工業(yè)已經(jīng)利用細(xì)菌來(lái)生產(chǎn)用于生物洗滌劑,、生物藥劑等的蛋白質(zhì)。但是有些生物技術(shù)和生物醫(yī)學(xué)所需的蛋白質(zhì)很難使用目前的方法制造,?？茖W(xué)家們希望通過(guò)對(duì)Tat系統(tǒng)的駕馭能夠更容易地制造這些蛋白質(zhì)。
??東英格蘭大學(xué)的教授,、擁有英國(guó)醫(yī)學(xué)研究理事會(huì)（MRC）研究院職位的Tracy Palmer說(shuō)：“Tat系統(tǒng)通過(guò)辨認(rèn)連接在蛋白質(zhì)末端的信號(hào)序列來(lái)確定分泌哪些蛋白質(zhì),。我們?cè)谫e夕法尼亞大學(xué)的合作者們開(kāi)發(fā)了一個(gè)計(jì)算機(jī)程序來(lái)搜尋細(xì)菌的基因組，從而預(yù)測(cè)系統(tǒng)中會(huì)使用哪些蛋白質(zhì),。研究中我們發(fā)現(xiàn)了被系統(tǒng)識(shí)別的很大數(shù)量的信號(hào)序列,。我們下一步是把這些信號(hào)序列連接在醫(yī)學(xué)上很重要的蛋白質(zhì)，這樣就能利用Tat系統(tǒng)分泌這些蛋白質(zhì)了,。”
??這項(xiàng)工作是作為英國(guó)的“生物技術(shù)和生物科學(xué)研究委員會(huì)”（BBSRC）的基因組開(kāi)發(fā)計(jì)劃（Exploiting Genomics Initiative）的一部分,。最近，Palmer的小組加入了整個(gè)歐洲隊(duì)Tat系統(tǒng)進(jìn)行研究的“Tat 機(jī)器計(jì)劃”中,。
英文原文：
Nature's nanomachines harnessed to make drugs
Many bacteria produce toxins that can threaten human health, however new research into how bacteria secrete these substances is giving clues as to how scientists could harness these processes to produce biopharmaceuticals. Researchers at the John Innes Centre (JIC) in Norwich have used state-of-the-art technology to study a nanomachine in soil bacteria called the Tat system, which the bacteria use to secrete a range of proteins that help them digest food and compete with other microorganisms in the soil.
The scientists?latest work, published today in the respected journal PNAS, identifies which proteins are exported via the Tat system, revealing that this system is used by more proteins than previously thought. The biotechnology industry already uses bacteria to make proteins to use in products such as biological washing powder or pharmaceuticals, but some are difficult to produce using current methods. By harnessing the Tat system, the scientists hope that it will be easier to make these proteins for biotechnological and biomedical purposes.
"The Tat nanomachine selects which proteins to secrete by recognising a short signal sequence attached to the end of the protein", explains Professor Tracy Palmer who has an MRC Fellowship with the University of East Anglia. "Our collaborators at the University of Pennsylvania have developed a computer program to search the bacterial genome to predict which proteins use the Tat system, and in this study we have verified their results experimentally and found a significant number of signals that are recognised by this system. The next step is to attach these signals to medically important proteins so they can be secreted by the bacteria using the Tat system."
The foundation work for this project was started as part of the BBSRC's Exploiting Genomics Initiative; more recently Prof Palmer抯 team has joined forces with the "Tat Machine Project", an EU-funded consortium of researchers from across Europe studying the Tat system. In addition to using the Tat nanomachine to improve production of biopharmaceuticals, the consortium are studying the system in several different types of bacteria, including pathogenic species like E. coli O157 and Pseudomonas aeruginosa to explore Tat as a potential target for new antibiotics.
