2014.07.11【英译中】SCI 连载之一

小妮丫头 (流火) 路人甲
37 5 0
发表于:2014-07-11 23:47 [只看楼主] [划词开启]

2014.07.11【英译中】SCI 连载之一


楼主最近学术狗模式开启,就不 @ 各位亲朋了。

By 楼主


Abstract

Genome sequencing of Streptomyces, myxobacteria, and fungi showed that although each strain contains genes that encode the enzymes to synthesize a plethora of potential secondary metabolites, only a fraction are expressed during fermentation. Interest has therefore grown in the activation of these cryptic pathways. We review current progress on this topic, describing concepts for activating silent genes, utilization of “natural” mutant-type RNA polymerases and rare earth elements, and the applicability of ribosome engineering to myxobacteria and fungi, the microbial groups known as excellent searching sources, as well as actinomycetes, for secondary metabolites.

摘要:

链霉菌属、粘细菌以及真菌的基因组序列分析结果显示,虽然每个菌种包含着许多能合成潜在次级代谢产物的酶的基因,只有少部分基因会在发酵过程中表达。因此,对于这些潜在途径的激活方式的探索成为一个有趣的课题。我们搜集并回顾有关这个热点的研究进程,整理了如下几个方面:1、描述了激活沉默基因的概念;2、自然存在的突变型RNA聚合酶和稀土元素的利用;3、粘细菌和真菌的核糖体工程可应用性分析;4、微生物群体,包括放线菌,被认为是发掘次级代谢产物的有效资源。

 

Introduction

Applied microbiology seeks, for example, to identify the latent activities of microorganisms and to enhance these activities at the industrial level by strain improvement. Current methods of strain improvement, ranging from classical random approaches to metabolic engineering, however, are either costly or laborintensive (Santosand Stephanopoulos 2008). Moreover, after 1970, the rate of discovery of useful compounds declined progressively, despite the constant need for new and improved drugs to combat emerging and reemerging infectious diseases and cancer. Recent advances in DNA sequencing technologies have enabled multiple genomes to be sequenced rapidly and inexpensively. Streptomyces genome sequencing showed that each strain contains genes that encode the enzymes to synthesize 20 or more potential secondary metabolites (Bentley et al. 2002; Ikeda et al.2003;Ohnishietal.2008), only a fraction of which are expressed during fermentation. These cryptic biosynthetic pathways may produce many novel bioactive compounds with the potential to rejuvenate stalled drug discovery pipelines. Methods to activate these silent biosynthetic pathways are thus of major interest. The key issue for the success of this approach is to find ways to induce or enhance the expression of cryptic or poorly expressed pathways to provide material for structure elucidation and biological testing. Thus, strategies for rapid strain improvement will likely shift from the improved expression of well-known, highly productive, secondary metabolites of fermentation to the expression of novel and often cryptic secondary metabolite pathways (Baltz 2011). This approach may solve the early stage discovery problems of: (a) inducing some level of expression of cryptic biosynthetic gene clusters [waking the sleeping genes] and (b) rapidly increasing product yields to obtain enough material to characterize chemically and biologically [early stage yield enhancement].

前言

应用微生物学,比如说,就是一门发掘微生物潜在活性,并且通过菌种选育提供其在产业层面的活性。就目前的菌种选育方法来说,从传统的随机方法选育到代谢工程,不是造价太高就是劳动强度过大。1970年以后,即便在治疗及治愈新型传染病和癌症方面的新型和改良药剂不断在以一种稳定的速度增长,有用化合物的发现速度仍在逐年减少。DNA测序技术的发展使得多倍体基因组测序工作快速廉价的完成成为可能。链霉菌属基因组测序结果显示,每个种都包含着能合成至少20个潜在次级代谢产物的酶的功能基因,但只有极少部分在其发酵过程中会表达。这些隐藏的生物合成途径可能产生很多新兴的活性物质,甚至能成为一部分药物重新焕发活力的发现方法。因此,如何激活这些生物合成途径的沉默基因成为最主要的课题。解决这个问题的关键性方法是,找寻一种可以诱导或者强化这种隐藏表达或者弱表达的途径,最后通过产物的结构分析和活性测定进行验证。所以,在快速的改良菌种进程中研究重点,很可能从一种常见的、次级代谢物高表达的、改良后的发酵方式表达转移到一种新兴的,通常是一种潜在次级代谢途径的表达上来。这种方法能够解决现初级阶段遇到的问题,如:(a) 诱导同水平下潜在生物合成基因簇的表达[激活沉默基因](b) 快速增加代谢产物产量以便能够获得足够的实验材料进行化学结构分析和活性测定[初级阶段的增强作用]


最后编辑于:2014-07-11 23:58
分类: 英语
全部回复 (5)

  • 0

    点赞

  • 收藏

  • 扫一扫分享朋友圈

    二维码

  • 分享

课程推荐

需要先加入社团哦

编辑标签

最多可添加10个标签,不同标签用英文逗号分开

保存

编辑官方标签

最多可添加10个官方标签,不同标签用英文逗号分开

保存
知道了

复制到我的社团