人工微生物混菌系统机制解析中的组学应用及进展

人工微生物混菌系统的生物工程应用价值日益受到重视,使得对于混菌系统中成员菌间的相互作用机制研究也成为近年来的一个热点。其研究结果一方面可以为现有人工混菌系统的进一步优化提供理论依据,另一方面也为全新混菌系统的人工构建提供新的思路和策略,进而促进人工微生物混菌系统未来规模化应用。基因组学、转录组学、蛋白质组学和代谢组学等研究方法能够高通量分析各种生物分子、提供大量的数据与信息,多组学分析可以获得混菌系统中细胞的“全景”,在揭示人工微生物混菌系统中各个成员间的相互作用的研究中有着特殊的意义。文中综述了近年来多种组学技术在人工微生物混菌系统机制解析中的应用及研究进展,从代谢网络、能量代谢、信号转导、膜转运、胁迫响应、混菌系统的稳定性以及结构合理性等方面探讨混菌系统机制解析的最新进展,以期为利用合成生物学、基因组编辑等新兴生物技术改造微生物混菌系统实现其工程化应用提供理论依据。     

光照混菌培养应用研究进展

光合细菌与其他微生物在光照条件下混合培养是近年来的研究热点。综述了光照混菌培养的特点和目前光照混菌培养在水体净化、生物制氢和高价值物质生产方面的应用,并对影响混合菌株生长代谢与繁殖的因素做了总结。分析表明菌株之间存在的相互协同共生作用能促进微生物的生长繁殖,使底物被充分利用,提高物质产率。光照混菌培养工艺简单、成本较低,在水体净化、生物制氢、高价值物质生产方面的应用具有相当好的效果。在影响因素中对混合培养影响最大的因素是菌株接种量、接种比和培养基pH。在总结光照混菌培养应用现存不足的基础上,对其发展前景作出展望。     

生态工程领域微生物菌剂研究进展

阐述了微生物菌剂在生态工程领域的应用范围、效果和国内外的研究状况,总结了目前微生物菌剂研制中菌种的选育方法和常用的几类菌,并通过系统举例介绍了乳酸菌、酵母菌、光合细菌、芽孢杆菌这些常用菌种在污染物处理方面的效果及在废水处理生态工程方面的相关研究进展。同时,阐明了微生物混合培养技术在复合菌剂研究中的重要性,对微生物菌剂的作用机理进行了探讨,指出了目前关于微生物菌剂的研究大多只是集中于应用效果方面,而对作用机理研究得不够深入,以及复合菌系中微生物相互作用和影响的复杂性,并对此提出了一些建议。最后,对微生物菌剂的应用前景进行了展望。     

光合细菌在水污染治理中的研究进展

光合细菌以其无毒、繁殖快、适应能力强、易人工培养等优点而在环境治理中受到重视。国内外对光合细菌的研究主要集中在水产养殖业(如净化水质,作饵料添加剂等)和生活及工业重污染水处理中的作用,关于光合细菌在景观微污染水体治理方面的作用研究较少。课题组研究发现光合细菌中的沼泽红假单胞菌对西南大学景观水中氨氮的去除率高达95%,暗示光合细菌能有效治理景观水污染。综述了光合细菌的分类、脱氮除磷原理以及目前光合细菌在治理有机废水、重金属废水和养殖污水方面的应用,并展望了光合细菌在处理景观微污染水体方面的应用前景,以期为进一步研究光合细菌在景观水治理中的作用提供参考。     

微生物共培养技术的研究进展

摘要:本文对微生物共培养的发展历史及其在食品、农业、工业及污水净化等方面的应用进行了综述,并对已知的共培养微生物之间的生态学关系进行了总结。人们利用微生物联合共培养、序列共培养和共固定化细胞混菌培养等技术来获得新的代谢产物,提高产量,改造传统发酵工业,生产能源物质,提高底物利用率,扩大底物范围,降解有毒物质。共培养微生物之间可能具有协同代谢作用、诱导作用、种间群体感应、基因转移等多种生态学关系。对共培养微生物之间的微生态机理进行深入系统的研究,有助于充分发挥共培养技术的应用潜力。     

微生物发酵生产多糖的研究进展

微生物是一种能生产多糖的可再生资源,微生物多糖因独特的生理活性和广阔的应用前景而备受人们的关注.本文阐述了微生物多糖的产生菌和发酵培养条件等方面的研究进展,以期对微生物多糖的深入研究和广泛应用有一定的指导意义.     

微生物与能源

对以甲烷产生菌、乙醇产生菌和氢气产生菌为代表的能源性微生物进行了主要类群分类、产生能源的代谢性作用机理和应用该类微生物产生能源的总体生产前景做了较为系统的概括性阐述。能源性微生物不仅在微生物教学中非常重要,而且该类微生物在环境保护、非再生性能源节约和提高有关领域综合效益等方面,都具有直接的、显著的促进作用。     

微生物固碳的电子供给策略研究进展北大核心CSCD

随着生物化工技术的不断发展成熟,通过改造微生物已可以实现二氧化碳、甲烷等温室气体的固定、转化和利用,而电子传递及能量供给对微生物固碳效率起着决定性的作用。本文首先分析了好氧性嗜甲烷菌、化能自养微生物等天然微生物细胞内外的直接、间接电子传递系统。在此基础上,围绕微生物固碳细胞工厂的构建,进一步介绍了基于光能、电能的人工电子供给策略及其对固碳过程中代谢通量、合成路径和供能效率的影响。最后针对微生物固碳的关键共性技术难点,简要展望了可行性的解决方案及相关应用前景。     

合成芳香族化合物的酵母底盘改造策略*

芳香族化合物种类丰富,在多个行业具有广泛的用途,需求量大。通过构建微生物细胞工厂合成芳香族化合物具有独特的优势和工业化应用前景,其中酵母底盘因其清晰的遗传背景、完善的基因操作工具以及成熟的工业发酵体系等优势,常被用于构建细胞工厂。目前改造酵母底盘生产芳香族化合物的研究取得了一系列进展,并针对关键问题提出了一些可行的解决策略。针对酵母合成芳香族化合物的策略与挑战,从芳香族化合物合成路径改造、多样化碳源利用及转运系统改造、基因组多靶点改造、特殊酵母底盘及混菌系统构建、合成生物学高通量技术的应用这五个方面进行系统地梳理和阐述,为生产芳香族化合物的酵母底盘构建与改造提供思路。     

有效微生物群EM的应用及研究现状

有效微生物群（EffectiveMicroorgsnisms,简称EM）是日本琉球大学比嘉照夫教授研究成功的一种新型复合微生物活菌制剂,由光合细菌、酵母菌、乳酸菌、放线菌及发酵型丝状真菌等5科10属80多种微生物复合培养而成。其特点是采用独特的发酵工艺把好气性微生物和嫌气性微生物按一定比例加以混合,培养有效微生物群体。它们互相组合在一起,形成一个复杂的微生物生态系统。这个系统犹如一个微生物加工厂,各样微生物在其生长过程中产生出的有用物质及其分泌物质,成为各自或相互生长的基质或原料,从而形成相互间的共生增殖关系,相互作用,发…     

海洋动物来源微生物的共培养研究进展

近年来,由于一些新疾病的发生和细菌耐药性的出现,微生物来源次级代谢产物的筛选重复率越来越高,微生物一些代谢基因在现有实验室条件下无法表达,所以需要发现新的微生物资源,同时找到激活微生物代谢产物基因的方法。海洋动物体内蕴含着大量的共附生微生物资源,可以产生很多具有生物活性的化合物,是潜在的药用资源。本文综述了近年来海洋动物(海鞘、海绵、珊瑚和海葵等)来源的微生物进行共培养的研究策略,包括共培养菌株的选择、共培养条件、群体感应和信号分子对共培养菌株的影响,以及不同种类微生物间的共培养实例。共培养与单培养相比,增加了次级代谢产物的种类,提高了次级代谢产物的生物活性或产量。共培养的研究有助于发现新的海洋动物来源微生物的活性天然产物,为海洋药物的开发提供新思路。     

Current advances in biological production of propionic acid

Propionic acid and its derivatives are considered “Generally Recognized As Safe” food additives and are generally used as an anti-microbial and anti-inflammatory agent, herbicide, and artificial flavor in diverse industrial applications. It is produced via biological pathways using Propionibacterium and some anaerobic bacteria. However, its commercial chemical synthesis from the petroleum-based feedstock is the conventional production process bit results in some environmental issues. Novel biological approaches using microorganisms and renewable biomass have attracted considerable recent attention due to economic advantages as well as great adaptation with the green technology. This review provides a comprehensive overview of important biotechnological aspects of propionic acid production using recent technologies such as employment of co-culture, genetic and metabolic engineering, immobilization technique and efficient bioreactor systems.     

Photobiological hydrogen production: Recent advances and state of the art

Photobiological hydrogen production has advanced significantly in recent years, and on the way to becoming a mature technology. A variety of photosynthetic and non-photosynthetic microorganisms, including unicellular green algae, cyanobacteria, anoxygenic photosynthetic bacteria, obligate anaerobic, and nitrogen-fixing bacteria are endowed with genes and proteins for H₂-production. Enzymes, mechanisms, and the underlying biochemistry may vary among these systems; however, they are all promising catalysts in hydrogen production. Integration of hydrogen production among these organisms and enzymatic systems is a recent concept and a rather interesting development in the field, as it may minimize feedstock utilization and lower the associated costs, while improving yields of hydrogen production. Photobioreactor development and genetic manipulation of the hydrogen-producing microorganisms is also outlined in this review, as these contribute to improvement in the yield of the respective processes.     

Engineering biofuel tolerance in non-native producing microorganisms

Large-scale production of renewable biofuels through microbiological processes has drawn significant attention in recent years, mostly due to the increasing concerns on the petroleum fuel shortages and the environmental consequences of the over-utilization of petroleum-based fuels. In addition to native biofuel-producing microbes that have been employed for biofuel production for decades, recent advances in metabolic engineering and synthetic biology have made it possible to produce biofuels in several non-native biofuel-producing microorganisms. Compared to native producers, these non-native systems carry the advantages of fast growth, simple nutrient requirements, readiness for genetic modifications, and even the capability to assimilate CO₂ and solar energy, making them competitive alternative systems to further decrease the biofuel production cost. However, the tolerance of these non-native microorganisms to toxic biofuels is naturally low, which has restricted the potentials of their application for high-efficiency biofuel production. To address the issues, researches have been recently conducted to explore the biofuel tolerance mechanisms and to construct robust high-tolerance strains for non-native biofuel-producing microorganisms. In this review, we critically summarize the recent progress in this area, focusing on three popular non-native biofuel-producing systems, i.e. Escherichia coli, Lactobacillus and photosynthetic cyanobacteria.     

微藻与其他微生物共培养的研究进展及应用

化石燃料的挖掘和燃烧导致环境污染以及气候变化。与化石燃料相比,微藻被认为是一种更有前途的生物柴油生产原料,它具有生长速度快、含油量高、不占用耕地的特点。尽管微藻被认为是生产第三代生物燃料的最佳生产者之一,但单独培养微藻容易污染且采收成本高,与化石燃料和传统可再生能源相比缺乏竞争力。利用微藻与其他微生物共培养能够实现自絮凝降低微藻采收成本,而且培养体系不易污染、油脂产率与高价值副产物产量较高。因此,微藻与其他微生物共培养是一种经济、节能、高效的技术,具有广阔的应用前景。文中综述了近年来微藻与其他微生物共培养的研究现状、相互作用机制以及影响微藻产油的因素,总结了微藻与其他微生物共培养技术的应用,最后对微藻与其他微生物共培养体系发展的前景与挑战进行了展望。     

Metabolite induction via microorganism co-culture: A potential way to enhance chemical diversity for drug discovery

Microorganisms have a long track record as important sources of novel bioactive natural products, particularly in the field of drug discovery. While microbes have been shown to biosynthesize a wide array of molecules, recent advances in genome sequencing have revealed that such organisms have the potential to yield even more structurally diverse secondary metabolites. Thus, many microbial gene clusters may be silent under standard laboratory growth conditions. In the last ten years, several methods have been developed to aid in the activation of these cryptic biosynthetic pathways. In addition to the techniques that demand prior knowledge of the genome sequences of the studied microorganisms, several genome sequence-independent tools have been developed. One of these approaches is microorganism co-culture, involving the cultivation of two or more microorganisms in the same confined environment. Microorganism co-culture is inspired by the natural microbe communities that are omnipresent in nature. Within these communities, microbes interact through signaling or defense molecules. Such compounds, produced dynamically, are of potential interest as new leads for drug discovery. Microorganism co-culture can be achieved in either solid or liquid media and has recently been used increasingly extensively to study natural interactions and discover new bioactive metabolites. Because of the complexity of microbial extracts, advanced analytical methods (e.g., mass spectrometry methods and metabolomics) are key for the successful detection and identification of co-culture-induced metabolites.     

Dynamic flux balance analysis of batch fermentation: effect of genetic manipulations on ethanol production

In silico optimization of bioethanol production from lignocellulosic biomasses is investigated by combining process systems engineering approach and systems biology approach. Lignocellulosic biomass is an attractive sustainable carbon source for fermentative production of bioethanol. For enhanced ethanol production, metabolic engineering of wild-type strains—that can metabolize both hexose and pentose sugars or microbial consortia consisting of substrate-selective microbes—may be advantageous. This study presents a detailed in silico analysis of bioethanol production from glucose-xylose mixtures of various compositions by batch mono-culture and co-culture fermentation of specialized microbes. Dynamic flux balance models based on available genome-scale reconstructions of the microorganisms have been used to analyze bioethanol production, and the maximization of ethanol productivity is addressed by computing optimal aerobic–anaerobic switching times. Effects of ten metabolic engineering strategies that have been suggested in the literature for ethanol overproduction, have been evaluated for their efficiency in enhancing the ethanol productivity in the context of batch mono-culture and co-culture processes.     

Phytoplankton trigger the production of cryptic metabolites in the marine actinobacterium Salinispora tropica

Filamentous members of the phylum Actinobacteria are a remarkable source of natural products with pharmaceutical potential. The discovery of novel molecules from these organisms is, however, hindered because most of the biosynthetic gene clusters (BGCs) encoding these secondary metabolites are cryptic or silent and are referred to as orphan BGCs. While co-culture has proven to be a promising approach to unlock the biosynthetic potential of many microorganisms by activating the expression of these orphan BGCs, it still remains an underexplored technique. The marine actinobacterium Salinispora tropica, for instance, produces valuable compounds such as the anti-cancer molecule salinosporamide but half of its putative BGCs are still orphan. Although previous studies have used marine heterotrophs to induce orphan BGCs in Salinispora, its co-culture with marine phototrophs has yet to be investigated. Following the observation of an antimicrobial activity against a range of phytoplankton by S. tropica, we here report that the photosynthate released by photosynthetic primary producers influences its biosynthetic capacities with production of cryptic molecules and the activation of orphan BGCs. Our work, using an approach combining metabolomics and proteomics, pioneers the use of phototrophs as a promising strategy to accelerate the discovery of novel natural products from marine actinobacteria.