信息

2012-01可提高生物燃料生产效率的细菌基因用微生物分解农作物和农业废料来生产乙醇,是生物燃料研究的主要方向。美国能源部生物能源科学中心研究小组新近发现一个基因,可望帮助提高微生物生产乙醇的效率、降低生产成本。在用于生产燃料乙醇的一种细菌——热纤梭菌中,新发现的基因决定着细菌对乙醇的耐受力。热纤梭菌能发酵降解纤维素产生乙醇。由于它能自行制造降解过程所需要的酶,不需要添加昂贵的催化剂,在生物燃料方面有很大应用价值。     

发酵设备和管道设计的要点

发酵设备是指应用微生物生产目的产物的设备。发酵工业最早有涉及人们生活的酒、酱油、调味品等酿造工业,后来有青霉素等抗生素、维生素、激素为代表的生理活性物质、酶工业、有机酸工业等,发展很快。近年来,微生物学更引人关注。尤以医药为中心,应用微生物新发酵领域的开发、各种抗癌药物、干扰素等新闻报道大量涌现。本文主要介绍深层培养微生物时,好气发酵的设备和管道设计以及施工方面的注意事项。     

假单胞菌多糖对肿瘤细胞和淋巴细胞的作用

多糖是重要的生物高分子化合物，近年来多糖类药物为癌症和艾滋病等疑难病症的治疗提供了新的方向。微生物多糖尤其是真菌多糖具有提高免疫功能和抗肿瘤作用的研究已有很多报道，细菌多糖的生物活性也逐渐引起重视。有研究显示，细菌所产生的糖复合物具有各种生物活性，可诱导产生不同的细胞因子。     

微生物产物的新用途

“特效药”是指微生物化学制品对于致病细菌、真菌和肿瘤的选择性作用。它的发现开创了“抗生素时代”。四十多年来我们已成了抗生素的卓越疗效的受益者。微生物次级代谢物的应用成功率竟如此之高,在抗细菌、抗真菌和抗肿瘤的化学治疗上占有优势。但不幸地,认为微生物次级代谢物的潜力有限的观点已妨碍了发酵工业的进一步发展。许多工业微生物学家子感到抗生素的活性几乎     

利用微生物酶与细胞制品合成寡肽抗生素

微生物酶与细胞主要应用于水解与生物转化反应。目前应用固定化酶或细胞作催化剂全酶合成已知或新的抗生素,并进一步应用此概念进行肽类抗生素领域的转化和发酵。细菌、酵母菌、放线菌、真菌均可产生     

现代中药发酵研究现状及思路

现代中药发酵是在传统中药发酵基础上,结合发酵工程、微生物工程及生物工程等学科而发展起来的中药生物转化技术,本质上是指在可控的条件下,借助微生物对中药成分分解和代谢,从而改变中药药性或药效。现代中药发酵具有不受自然条件制约,微生物转化能力强,发酵产物丰富,应用范围广等优势,是中药研究热点方向之一。本文针对目前发酵中药研究现状,对中药发酵方式、发酵菌种和中药发酵运用等研究现状进行综述,旨在提出中药发酵的研究思路,以期为中药深入研究及中药发酵开发利用提供一定的参考。     

浅析菌种质量控制

生产用菌种 ,经长期使用和保藏后 ,会发现发酵单位低 ,产生泡沫多 ,菌丝变形等异常现象 ,这标示着菌种的退化 ,导致菌种质量低劣 ,应用该菌种会直接影响发酵生产 ,菌种质量是影响发酵成败的关键因素之一。针对菌种质量这一问题 ,结合菌种本身的特征及菌种制备的方法和条件 ,对已退化的菌种进行处理 ,恢复该菌种原有优良性状 ,是保证生产稳定性的基础。本报道以细菌为例进行探讨。1　影响菌种质量的因素1 1　培养基的营养成分1 1 1　碳源　碳源是构成微生物细胞和代谢产物的碳架及供给菌种生命活动所需能量的营养物质。其主要功能为 :为微生…     

石莼、网地藻多糖含量与藻际微生物丰度关系研究

目的：研究石莼、网地藻藻际微生物丰度对多糖含量的影响。方法：通过实时荧光定量PCR(Real-time PCR)技术对石莼、网地藻所附着的藻际微生物丰度进行研究(细菌16S rDNA以及真菌18S rDNA丰度)。结果：石莼多糖含量、藻际微生物总DNA含量均显著高于网地藻(p <0.05)。石莼藻际微生物丰度(细菌1.04×1010-1.42×1010拷贝数/g干样,真菌1.01×107-1.38×107拷贝数/g干样) 显著高于网地藻(细菌2.05×108-6.9×108拷贝数/g干样、真菌2.59×105-4.79×105拷贝数/g干样)(p<0.01)。典型对应分析(CCA分析)表明石莼、网地藻多糖含量与藻际微生物(细菌、真菌)丰度显著相关。结论：石莼、网地藻藻际微生物丰度对多糖含量有一定影响。     

MALDI-TOF MS 技术在微生物检验中的应用效果

目的 探讨MALDI-TOF MS技术在微生物检验中的应用效果。方法 选取2021年7月至2022年7月进行检验的540例血培养阳性样本为研究对象,每份样本分为2份,1份540例直接应用MALDI-TOF MS技术实施微生物检验,另1份540例进行标本接种后细菌鉴定,前者设为微生物检验组,后者设为细菌鉴定组,比较两组病原菌检出情况与感染检出情况。结果 540份样本共分离出540株病原菌,革兰阳性菌分布如下,凝固酶阴性葡萄球菌有183例,金黄色葡萄球菌有37例,肠球菌有36例,链球菌有32例,革兰阳性杆菌9例,其他17例;革兰阴性菌分布如下,肠杆菌科细菌160株,革兰阴性非发酵菌44株,其他8株;酵母样真菌分布如下,白念9株,其他5株。细菌鉴定组的革兰阳性菌、革兰阴性菌、酵母样真菌检出率高于微生物检验组,差异有统计学意义（P <0.05）。结论 在微生物检验中应用MALDI-TOF MS技术可检出病原菌与感染性疾病,但检出价值低于细菌鉴定,如有必要可联合应用细菌鉴定,进一步明确患者的病原菌类型。     

23价肺炎球菌多糖疫苗定量检定质量趋势分析

目的:统计分析2006-2011年生产的140批23价肺炎球菌多糖疫苗的5项定量检定指标,为疫苗的质量评价和质量监督提供依据。方法:对2006-2011年生产的140批23价肺炎球菌多糖疫苗的多糖含量、苯酚含量、氯化钠含量、pH值、细菌内毒素检查等5项指标的检定结果进行统计分析;对各单型多糖的含量进行移动标准偏差分析;对苯酚含量、氯化钠含量、pH值测定、细菌内毒素检查指标进行移动平均值总体趋势分析。结果:6年来,23价肺炎球菌多糖疫苗的多糖含量批间差异逐渐缩小;苯酚含量、氯化钠含量、细菌内毒素检查均值逐渐下降并趋于稳定;pH值一直较为稳定。结论:2006-2011年生产的23价肺炎球菌多糖疫苗质量逐步提高并保持稳定。     

1,3-二羟基丙酮的分离提取研究进展

1,3-二羟基丙酮(1,3-dihydroxyacetone,DHA)是一种简单酮糖,作为甘油的高附加值产物,在医药、化工领域有广泛的应用前景。微生物发酵生产DHA的方法以其反应条件温和、底物利用率高、副产物少、工艺简单、易于控制等优点成为了目前国内外生产DHA应用的主要方法,但由于DHA在水溶液中溶解度极大,对热极其敏感等特性导致其分离提取成本高、能耗大,成为了工业生产上的一大难题。该文介绍了1,3-二羟基丙酮生产过程中产物分离提取的研究现状和技术开发进展。对以甘油为原料,微生物发酵法制备DHA的研究进行了展望。     

Tracing the past half century of my microbial transformation studies

In the middle of 1950's, microbial transformation technology was introduced into the field of synthetic chemistry as a new methodology. There was a sudden interest in research on the problems of producing steroid hormones by microbial transformation. At that time, the first project entitled "The Study for Microbial Transformation of Steroids", the "Tsuda Project", was established in the Institute of Applied Microbiology (IAM), University of Tokyo, in the spring 1956, in which I took part. This paper summarizes a number of results of our microbial transformation reactions not only in the synthesis of steroidal compounds, but also more broadly for other organic compounds, such as pravastatin, etc. The results are divided into five categories: 1) Microbial transformation of steroids, 2) Correlation between isolation sources of Pseudomonas spp. and their transformation activities, 3) Fermentation Production of prednisolone by Bacillus pulvifaciens SANK 71760, 4) Microbial transformation of siccanin, and 5) Development and fermentation production of pravastatin. About 30 years later, almost at the end of my microbial transformation studies, I had the opportunity to find some microbial strains having superior hydroxylation ability of ML-236BNa to pravastatin. Fortunately, Streptomyces carbophilus SANK 62585 was finally selected as a potent microbial converter with the formation of a lesser amount of by-products. With the view of industrial production of pravastatin, many studies and improvements were made to the culturing conditions to obtain productivity available commercially.     

微生物来源的抗生素JXJ-301-1的研究

从一株未鉴定的微生物菌株的次级代谢产物中分离到一个化合物JXJ-301-1,通过对该化合物在氘代氯仿和氘代二甲亚砜两种溶剂中的核磁共振数据分析,结合质谱、红外光谱和元素分析,证明该化合物是鬼臼毒素。本研究扩展了鬼臼毒素的来源。     

基于微生物互作的新天然产物发掘研究进展

在自然界中,微生物以群落状态生存,通过物种内或物种间的相互作用,不断重塑生态关系来实现共同进化。这种相互作用促使微生物合成大量复杂的次级代谢产物作为通讯工具或者化学武器,来适应环境变化,这些小分子则是药物发现的重要源泉。微生物共培养技术通过模拟自然生态关系,激活沉默基因簇来促进新型天然产物的发现。综述基于不同共培养体系的微生物天然产物挖掘最新进展,重点介绍微生物之间的相互作用机制以及沉默基因簇激活的分子机制,为微生物天然产物的化学多样性挖掘提供参考。     

微生物絮凝剂应用进展与发展前景

微生物絮凝剂具有降解性能好、应用广泛、成本低、操作简单及不会导致二次污染等优点,正日益引起人们的广泛重视。综述了微生物絮凝剂的种类、絮凝机理,微生物高产菌株以及在废水处理、饮用水处理和食品发酵工业的应用,并对其发展趋势作了简单的展望。     

微生物法生产丙酮酸的代谢工程研究进展

丙酮酸是细胞代谢的关键中间产物,为多种氨基酸、油脂、生物碱类、萜类的合成前体,现已广泛应用于食品、医药、化工等领域,市场需求日益增加.丙酮酸可以通过化学合成法、生物催化转化法及微生物发酵法生产.其中微生物发酵法具有原料廉价易得、环境污染小、产物纯度高等优点.文章系统分析了微生物中丙酮酸的生物合成途径和代谢调控,综述了代...     

Biotechnology and genetic engineering in the new drug development. Part III. Biocatalysis,metabolic engineering and molecular modelling

Industrial biotechnology has been defined as the use and application of biotechnology for the sustainable processing and production of chemicals, materials and fuels. It makes use of biocatalysts such as microbial communities, whole-cell microorganisms or purified enzymes. In the review these processes are described.Drug design is an iterative process which begins when a chemist identifies a compound that displays an interesting biological profile and ends when both the activity profile and the chemical synthesis of the new chemical entity are optimized. Traditional approaches to drug discovery rely on a stepwise synthesis and screening program for large numbers of compounds to optimize activity profiles. Over the past ten to twenty years, scientists have used computermodels of newchemical entities to help define activity profiles, geometries and relativities. This article introduces inter alia the concepts ofmolecularmodelling and contains references for further reading.     

Drug development from natural fermentation products: establishing a manufacturing process which maximizes the potential of microorganisms

Natural fermentation products have long been studied as attractive targets for drug discovery due to their amazing diverse, complex chemical structures and biological activities. As such, a number of revolutionary drugs developed from natural fermentation products have contributed to global human health. To commercialize a drug derived from natural fermentation products, an effective chemical entity must be identified and thoroughly researched, and an effective manufacturing process to prepare a commercial supply must be developed. To construct such a manufacturing process for tacrolimus and micafungin, the following studies were conducted: first, we focused on controlling the production of the tacrolimus-related compound FR900525, a fermentation by-product of tacrolimus which was critical for quality assurance of the drug substance. FR900525 production was reduced by using a mutant strain which produced more pipecolic acid, the biosynthesis material of tacrolimus, than the original strain. Then, to optimize the fermentation process of FR901379, an intermediate of micafungin, a fed-batch culture was adopted to increase FR901379 productivity. Additionally, FULLZONE(TM) impeller was installed into the scaled-up fermenter, reducing the agitation-induced damage to the mycelium. As a result, the mycelial form changed from filamentous to pellet-shaped, and the air uptake rate during fermentation was drastically improved. Finally, we conducted screening for FR901379 acylase-producing microorganisms, as FR901379 acylase is necessary to manufacture micafungin. We were able to easily discover FR901379 acylase-producing microorganisms in soil samples using our novel, convenient screening method, which involves comparing the difference in antibiotic activity between FR901379 and its deacylated product.     

Bacterial biopolymers: From production to applications in biomedicine

Bacterial polymers obtained tremendous attention over the decades owing to its widespread use in biomedical applications. A better understanding on metabolic pathways and development of improved production strategies through metabolic engineering tools to synthesize tailor made polymer materials to meet their applicability in biomedicine. This review focuses on wide range of these biocompatible polymeric materials include polysaccharides, polyesters, polyamides and polyphosphates with wound healing, antioxidant, antitumor, antimicrobial activities. This review focuses on the advantages of various biomaterials to obtain controlled/sustained drug release and tissue engineering applications in biomedical field and the applications of microbial polysaccharides as drugs in pharmaceutical industry. This review describes the most prominent biomedical applications of bacterial biopolymer material as wound healing bandages, drug delivery, tissue engineering, ortho-dental applications and hydrogels. Reviews the future aspects based on economic feasibility and challenges in mass production and downstream processing of biopolymers and its tailor made synthesis to accomplish diverse applications.     

Microbial models of mammalian metabolism. O-Dealkylation of 10,11-dimethoxyaporphine.

Microbial transformations of 10,11-dimethoxyaporphine were studied to determine the potential of microorganisms to produce monomethoxyaporphines. Ten microorganisms were identified as being capable of yielding apocodeine and/or isoapocodeine as the major metabolite in 24 and 20% yield, respectively. Cunninghamella blakesleeana (ATCC 9245) converted 10,11-dimethoxyaporphine quantitatively into isapocodeine. O-Dealkylation of this aporphine system is a facile microbial transformation, and the 10-methoxyl group is more susceptible to metabolic cleavage than the sterically hindered 11-methoxyl group. Selectivity in O-dealkylation may be accomplished with different microorganisms. This is the first report dealing with the microbial transformation of an aporphine system.