Creating and screening Cochliobolus heterostrophus non-ribosomal peptide synthetase mutants

An exhaustive characterization of the set of non-ribosomal peptide synthetase (NRPS) genes of the corn pathogen, Cochliobolus heterostrophus, and the small molecule peptides produced by the enzymes they encode, has been undertaken to ascertain the role of the peptide metabolites in the fungal cell. To date, the NRPS method of peptide biosynthesis has been described for filamentous ascomycete fungi (and to a limited extent, for basidiomycete fungi) and for bacteria, only. In addition to structural diversity, non-ribosomal peptides have a broad spectrum of biological activities, many are useful in medicine, agriculture, industry, and biological research. However, to suggest that inter-organismal activities is their primary function is likely incorrect; in fact, the physiological significance of these peptides to the producing fungi is largely unknown. We document that NRPS enzymes are purveyors of small molecules for both basal metabolism and for specialized environmental niches and that some are conserved, but most are not.     

CRISPR/Cas9在丝状真菌基因组编辑中的应用

丝状真菌(filamentous fungi)通常指那些菌丝体较发达且不产生大型肉质子实体结构的真核微生物。丝状真菌不仅在自然界物质循环中发挥着重要作用,还与人类健康和工农业生产有着紧密的联系。然而,对丝状真菌进行遗传操作相对困难,极大地妨碍了丝状真菌的遗传学研究。成簇的规律间隔的短回文重复序列及其相关系统(clustered regulatory interspaced short palindromic repeats/CRISPR-associated protein 9, CRISPR/Cas9)是近年来发现的一种存在于细菌和古菌中保守的获得性免疫防御机制。最近,CRISPR/Cas9被开发成为了一种方便灵活的基因组编辑技术。目前,该技术已经广泛应用在不同物种的基因组编辑中。本文概述了CRISPR/Cas9在丝状真菌基因组编辑中的应用进展,旨在为开展该领域的研究工作提供参考。     

中国柑橘菌物病原名录

我国是世界上最大的柑橘生产国,柑橘产业在我国农业生产中占有重要地位.菌物病害是制约我国柑橘产业效益的重要因素.在过去一百余年里,我国植物病理学家和菌物学家描述和记载了大量柑橘上的病原菌物.然而随着分子系统学在菌物分类鉴定中的广泛应用,以及菌物命名法规的变化,一些菌物的分类地位和拉丁学名发生了较大的变化.为了方便使用者了...     

丝状真菌G蛋白信号途径的研究进展

丝状真菌在工业、农业、医药等领域具有重要经济价值,一些亦可导致人类及动、植物疾病,造成经济损失.G蛋白信号途径是真核生物中普遍存在的细胞跨膜信号转导途径.近年来,丝状真菌中G蛋白信号途径的研究发展很快,相关报道表明该信号途径参与感应并传递多种胞外信号刺激,对丝状真菌的生长、分化、繁殖、致病性及真菌毒素等次生代谢产物合成有重要的调控作用.本文就丝状真菌中G蛋白信号途径的基本组成及其生理功能的研究现状进行简要综述.     

食用菌菌种现状及退化防控措施

随着食用菌产业迅速发展，菌种在食用菌生产中的重要地位凸显。食用菌菌种质量的优劣是影响食用菌产量和品质的重要因素之一，使用劣质菌种会存在食品安全隐患，也会给食用菌生产企业带来不必要的经济损失。菌种质量参差不齐、标准缺失或难以与国际对接，严重制约着食用菌产业的持续健康发展。本文从食用菌产业现状、食用菌菌种现状及存在问题、食用菌菌种退化因素及防控、食用菌菌种质量评价等方面进行了详细论述，从多个维度分析了菌种退化原因，总结了应对菌种退化的防控措施，从本质上解决菌种退化问题，以期为食用菌规模化生产及产业发展规划提供参考。     

Engineering Thermostable Microbial Xylanases Toward its Industrial Applications

Xylanases are one of the important hydrolytic enzymes which hydrolyze the β-1, 4 xylosidic linkage of the backbone of the xylan polymeric chain which consists of xylose subunits. Xylanases are mainly found in plant cell walls and are produced by several kinds of microorganisms such as fungi, bacteria, yeast, and some protozoans. The fungi are considered as most potent xylanase producers than that of yeast and bacteria. There is a broad series of industrial applications for the thermostable xylanase as an industrial enzyme. Thermostable xylanases have been used in a number of industries such as paper and pulp industry, biofuel industry, food and feed industry, textile industry, etc. The present review explores xylanase–substrate interactions using gene-editing tools toward the comprehension in improvement in industrial stability of xylanases. The various protein-engineering and metabolic-engineering methods have also been explored to improve operational stability of xylanase. Thermostable xylanases have also been used for improvement in animal feed nutritional value. Furthermore, they have been used directly in bakery and breweries, including a major use in paper and pulp industry as a biobleaching agent. This present review envisages some of such applications of thermostable xylanases for their bioengineering.     

Filamentous fungi as production organisms for glycoproteins of bio-medical interest

Filamentous fungi are commonly used in the fermentation industry for large scale production of glycoproteins. Several of these proteins can be produced in concentrations up to 20–40 g per litre. The production of heterologous glycoproteins is at least one or two orders of magnitude lower but research is in progress to increase the production levels. In the past years the structure of protein-linked carbohydrates of a number of fungal proteins has been elucidated, showing the presence of oligo-mannosidic and high-mannose chains, sometimes with typical fungal modifications. A start has been made to engineer the glycosylation pathway in filamentous fungi to obtain strains that show a more mammalian-like type of glycosylation. This mini review aims to cover the current knowledge of glycosylation in filamentous fungi, and to show the possibilities to produce glycoproteins with these organisms with a more mammalian-like type of glycosylation for research purposes or pharmaceutical applications     

丝状真菌遗传筛选系统的研究及其应用

随着基因组时代的发展,主要丝状真菌基因组测序基本完成而被广泛应用于工业、农业、医药等领域。然而丝状真菌的遗传转化效率极低,为了保证在大量非转化子背景下能筛选到目标转化子,恰当的筛选标记显得尤为重要。目前,在丝状真菌的遗传转化过程中常用的筛选标记可分为两类:药物抗性筛选标记和营养缺陷型筛选标记。但两者均具有一定的局限性,为此科研人员利用最新研究的基因组编辑技术对筛选标记加以修饰改造,以更好地用于遗传筛选。本文综述了目前常用的遗传筛选系统的分子机制及运用基因组编辑技术改造的新型筛选标记理论,为丝状真菌在各领域更广泛的应用奠定基础。     

Detection and identification of fungal species by electronic nose technology: A systematic review

A rapid and effective identification of fungal species is essential for numerous applications, and electronic nose systems are being proposed as suitable alternatives to currently available fungi identification techniques. Hence, the present review aims to unveil all published information concerning fungi identification by electronic nose systems.A systematic review of the literature was conducted according to the PRISMA guidelines. A total of 16 articles met the inclusion criteria and were included in the analysis. The results of the reviewed studies demonstrated that effective detection of fungi was possible through sensor-based electronic nose systems, which may actually function as a mycotoxin screening tool for several applications.The obtained results suggest that the sensor-based electronic nose systems may not only screen different fungi genera, but also identify the associated species. This technology has already been experimented in several fields, from food industry to clinical practice.By summarizing these results, the present review may accelerate the standardization of electronic noses in fungi detection and discrimination, allowing a faster and more efficient screening of samples.     

Impact of fungal molecular genetics on biotechnology

Summary The application of biotechnology has a very long history and life has benefited a lot from the application of fungal products. The industrial successful application of the use of fungi has been due to pioneering activities in both universities and industry. The most recent example of the application of a new technique was demonstrated with recombinant DNA techniques. Until now these techniques were mainly applied to rather simple processes. But we might also expect in the near future the application of these techniques to more complex systems. A very interesting area in this respect might be the production of plant secondary metabolites by fungi. As far as the economic benefits are concerned, a good balance has to be found between the economics of the processes and constrains posed on these processes by governmental regulations.     

我国食用菌产业技术路线图研究初报

在对产业发展形势与文献资料分析的基础上,提出我国食用菌产业发展路线图和产业链构成图,初步绘制了我国食用菌产业的技术路线图,同时对我国食用菌产业发展所面临的知识产权与保护、资金与融资、市场与环境等进行了分析,最后提出了加速发展我国食用菌产业的建议。     

Fungal biotechnology

Fungi are used in many industrial processes, such as the production of enzymes, vitamins, polysaccharides, polyhydric alcohols, pigments, lipids, and glycolipids. Some of these products are produced commercially while others are potentially valuable in biotechnology. Fungal secondary metabolites are extremely important to our health and nutrition and have tremendous economic impact. In addition to the multiple reaction sequences of fermentations, fungi are extremely useful in carrying out biotransformation processes. These are becoming essential to the fine-chemical industry in the production of single-isomer intermediates. Recombinant DNA technology, which includes yeasts and other fungi as hosts, has markedly increased markets for microbial enzymes. Molecular manipulations have been added to mutational techniques as a means of increasing titers and yields of microbial processes and in the discovery of new drugs. Today, fungal biology is a major participant in global industry. Moreover, the best is yet to come as genomes of additional species are sequenced at some level (cDNA, complete genomes, expressed sequence tags) and gene and protein arrays become available.     

Molecular tools for breeding basidiomycetes.

The industrial production of edible basidiomycetes is increasing every year as a response to the increasing public demand of them because of their nutritional properties. About a dozen of fungal species can be currently produced for food with sound industrial and economic bases. Notwithstanding, this production is threatened by biotic and abiotic factors that make it necessary to improve the fungal strains currently used in industry. Breeding of edible basidiomycetes, however, has been mainly empirical and slow since the genetic tools useful in the selection of the new genetic material to be introduced in the commercial strains have not been developed for these fungi as it was for other organisms. In this review we will discuss the main genetic factors that should be considered to develop breeding approaches and tools for higher basidiomycetes. These factors are (i) the genetic system controlling fungal mating; (ii) the genomic structure and organisation of these fungi; and (iii) the identification of genes involved in the control of quantitative traits. We will discuss the weight of these factors using the oyster mushroom Pleurotus ostreatus as a model organism for most of the edible fungi cultivated industrially.     

食用菌菌糠综合利用研究进展

中国是食用菌生产第一大国,每年产生约1亿多t菌糠,菌糠中含有大量的粗纤维和多糖等物质,但大部分菌糠都被当作废弃物直接丢弃或焚烧,造成严重的环境污染和资源浪费,同时也不符合我国新时期的环保政策,如何变废为宝,科学、环保、经济、合理地利用菌糠成为食用菌产业健康发展的重要环节。本文通过对食用菌菌糠综合利用的方式和现状进行阐述,探讨菌糠利用存在的主要问题,对未来菌糠利用的方向和发展趋势进行展望,为食用菌菌糠的高效利用提供参考和理论依据。     

草酸脱羧酶及其应用

草酸脱羧酶是一种含锰的酶,在白腐菌中广泛存在,少数低等真菌和细菌中也能产生。目前,至少10多种草酸脱羧酶得到了分离和纯化。该酶是一种氨基酸残基在379个左右的单体酶,一般都为酸性糖蛋白,含有2个锰离子,形成2个活性区域;表面一些氨基酸被不同程度地糖基化。晶体结构和其它一些波谱学研究解释了其空间结构和可能的电子传递机制。运用PCR技术和cDNA文库技术,越来越多的草酸脱羧酶基因被克隆。已研究的该酶基因中都含有17个左右的内含子,这些内含子在活性域位置上有比较高的保守性。一些特殊氨基酸序列的存在决定了该酶的表达形式为诱导型,菌株的基因调控序列中含有一段受草酸化合物作用的序列。该酶在一些酵母和植物等异源表达系统中有成功表达的报道。该酶的应用主要集中在以下几方面：造纸废水中的草酸盐降解;食品中的草酸降解;草酸生物检测（如,临床诊断）等。     

近十年中国重要食药用菌研究进展

食用菌跻身我国第五大农作物,我国已经成为名副其实的食药用菌大国。本文对近十年来食药用菌重要种类名称变更、人工培植或栽培技术的突破和基因组学研究的进展进行了综述。随着分子系统学研究的深入,灵芝、黑木耳、毛木耳、桑黄等重要种类的名称得到更正和完善;冬虫夏草、羊肚菌、暗褐网柄牛肝菌等难栽培种类在全世界范围内首次实现人工栽培;大多数常见食药用菌种类完成了基因组解析。分析了分类和系统发育研究、生物学研究、组学研究与食药用菌产业发展的关系,基础研究促进食药用菌产业发展,同时产业发展为基础研究提出更多的科学问题。     

Genetic transformation in Aspergilli: tools of the trade

DNA-mediated transformation is a powerful tool that allows the introduction of specific genetic changes in an organism. Transformation of Aspergilli, acclaimed for their wide use in the industry, has been possible for about two decades now. Several basic and applied problems related to fungal biology have been addressed using this technique. Nonetheless, new markers and strategies for transformation are still being developed for these filamentous fungi. Different methods and markers that are currently available for the transformation of Aspergilli are summarized here. The review also brings out the importance of these transformation systems in analyzing fungal gene function. Aspects of Aspergillus niger transformation are selectively emphasized.     

一种用于PCR扩增的丝状真菌DNA快速提取方法

丝状真菌在工业、农业、医药以及基础生物学研究中具有重要作用。利用遗传转化技术对丝状真菌进行菌株改良和基因功能分析, 也越来越受到重视。然而, 丝状真菌DNA提取方法繁琐、费时, 难以满足利用PCR技术高通量筛选转化子的需要。本文以曲霉菌为例建立了一种快速提取丝状真菌DNA的实验方法, 微波处理置于10 × TE buffer中的菌丝即可得到DNA。RAPD试验和PCR扩增证明, 该方法提取的DNA能够达到PCR扩增的要求。研究结果为高通量快速筛选丝状真菌转化子奠定了基础。     

Strategies for mining fungal natural products

Fungi are well known for their ability to produce a multitude of natural products. On the one hand their potential to provide beneficial antibiotics and immunosuppressants has been maximized by the pharmaceutical industry to service the market with cost-efficient drugs. On the other hand identification of trace amounts of known mycotoxins in food and feed samples is of major importance to ensure consumer health and safety. Although several fungal natural products, their biosynthesis and regulation are known today, recent genome sequences of hundreds of fungal species illustrate that the secondary metabolite potential of fungi has been substantially underestimated. Since expression of genes and subsequent production of the encoded metabolites are frequently cryptic or silent under standard laboratory conditions, strategies for activating these hidden new compounds are essential. This review will cover the latest advances in fungal genome mining undertaken to unlock novel products.     

我国食用菌产业化存在的问题及发展对策

我国是栽培食用菌最早的国家,食用菌产量居世界首位,食用菌产业化发展已具有一定规模。针对食用菌产业中存在的发展不均衡、生产规模偏小等问题,提出了开拓国内外市场、增加产品特色等发展对策,为加快食用菌产业化发展提供思路。