Process Design for the Microbial Synthesis of Poly‐β‐hydroxybutyrate (PHB) from Natural Gas

A process design for a two‐stage procedure for the production of PHB from natural gas based on the results, obtained on a laboratory and small technical scale, was developed. For this purpose, four bioreactors were dimensioned and interconnected so as to achieve a quasi‐continuous PHB production. A price of 6.35 €/kg PHB was pre‐calculated for the biosynthesis in a plant producing 500 t PHB/year. An extrapolation, which included the incorporation of various downstream procedures to achieve purities dependent on applications, resulted in prices between 11.50 and 14.00 €/kg for the purified final product. Estimations indicate that an expansion of the plant capacity to 5,000 t/year could enable a price reduction of approx. 30–35 %.     

有关生物技术成果转化的调查研究(上)

本文通过对中国科学院等研究机构的生物技术研究人员进行问卷调查,定性的描述了目前生物技术成果转化的总体状况和存在问题,运用相关统计分析方法阐明阻碍成果转化的因素及其结构,并提出相关解决策略 。     

Coordinated Development of Yeast Colonies: Quantitative Modeling of Diffusion‐Limited Growth – Part 2

A mathematical model was developed which described the growth of yeast colonies based on the assumptions that (i) these populations were built up of single cells whose proliferation was (ii) exclusively controlled by nutrient availability in the environment. The model was of a hybrid cellular automaton type and described discrete cells residing on a one‐dimensional lattice as well as on continuously distributed nutrients. Experimental results and numerical calculations were compared to elucidate under which cultivation conditions the diffusion‐limited growth (DLG) was the major construction principle in yeast colonies. Simulations were scaled to the growth of Yarrowia lipolytica and Candida boidinii colonies under carbon and nitrogen limitation. They showed that nutrient‐controlled growth of the individual cells resulted in DLG of the population. Quantitative predictions for the spatio‐temporal development of the cell‐density profile inside a growing yeast mycelium were compared to the growth characteristics of the model yeast mycelia. Only for the carbon‐limited growth of C. boidinii colonies on glucose as the limiting nutrient resource did the DLG model reproduce the cell‐density profile estimated at the end of the cultivation. Under all other cultivation conditions, strong discrepancies between calculations and experimental results were evident precluding DLG as the ruling regulatory mechanism. Thus, whether or not the development of a yeast population could be described by a DLG scenario, was strongly dependent on the particular cultivation conditions and the applied yeast species. In those cases for which the DLG hypothesis failed to explain the observed growth patterns, the underlying assumptions, i.e., the complete absence of nutrient translocation between the individual cells inside the yeast mycelia as well as the exclusively nutrient‐controlled proliferation of the cells, have to be reevaluated. The presented study demonstrated how the mathematical analysis of growth processes in yeast populations could assist the experimental identification of potential regulatory mechanisms.     

Evaluation of Various Unstructured Kinetic Models for the Production of Protease by Bacillus sphaericus MTTC511

Bacillus sphaericus MTCC511 was used for the production of protease in submerged batch fermentation. Maximum protease activity of 1010 U/L was obtained during a fermentation period of 24 h under optimized conditions of 30 °C in a medium with an initial pH of 7 and at a shaking rate of 120 rpm. The maximum biomass obtained in the batch fermentation was 2.55 g/L after 16 h. Various unstructured models were analyzed to simulate the experimental values of microbial growth, protease activity and substrate concentration. The unstructured models, i.e. the Monod model for microbial growth, the Monod incorporated Luedeking‐Piret model for the production of protease and the Monod‐incorporated modified Luedeking‐Piret model for the utilization of substrate were capable of predicting the fermentation profile with high coefficient of determination (R²) values of 0.9967, 0.9402 and 0.9729, respectively. The results indicated that the unstructured models were able to describe the fermentation kinetics more effectively.     

生物技术在食品领域的应用与发展趋势

生物技术是一门新兴的高新技术。简要综述了基因工程、细胞工程、蛋白质工程、酶工程、发酵工程等生物技术在食品领域的应用及其存在问题和发展趋势。     

Re‐engineering the μ‐conotoxin SIIIA scaffold

Voltage‐gated sodium (Na_v) channels are responsible for generation and propagation of action potentials throughout the nervous system. Their malfunction causes several disorders and chronic conditions including neuropathic pain. Potent subtype specific ligands are essential for deciphering the molecular mechanisms of Na_v channel function and development of effective therapeutics. µ‐Conotoxin SIIIA is a potent mammalian Na_v1.2 channel blocker that exhibits analgesic activity in rodents. We undertook to reengineer loop 1 through a strategy involving charge alterations and truncations which led to the development of µ‐SIIIA mimetics with novel selectivity profiles. A novel [N5K/D15A]SIIIA(3–20) mutant with enhanced net positive charge showed a dramatic increase in its Na_v1.2 potency (IC₅₀ of 0.5 nM vs. 9.6 nM for native SIIIA) though further truncations led to loss of potency. Unexpectedly, it appears that SIIIA loop 1 significantly influences its Na_v channel interactions despite loop 2 and 3 residues constituting the pharmacophore. This minimal functional conotoxin scaffold may allow further development of selective Na_V blockers. © 2013 Wiley Periodicals, Inc. Biopolymers 101: 347–354, 2014.     

A New Evaluation Method for 2‐D Fluorescence Spectra Based on Theoretical Modeling

This article presents a new evaluation procedure of 2‐D fluorescence spectra obtained during a yeast cultivation without performing a calibration measurement. The 2‐D fluorescence spectra are used to predict the process variables biomass, glucose and ethanol. The new calibration procedure uses a theoretical model of these process variables, i.e., differential equations, to replace any calibration measurement. The theoretical model parameters are identified simultaneously during the calculation of the chemometric models. The root mean square error of prediction of the chemometric models with respect to off‐line measurements are 1.5 g/L, 0.40 g/L and 0.56 g/L for glucose, biomass and ethanol, respectively.     

Monitoring and Control of Bioproducts from Conception to Production in Real‐time Using an Optical Biosensor

The ability to observe biological interactions in real‐time using optical biosensor technology provides the scientist/engineer with a valuable analytical tool to analyze biological molecules. Production of biological products is a growing area, but the course of discovery through to production is lengthy and complex, especially for therapeutic products. However, the economics of developing new products are clear, time to market for a new product is the primary consideration. Limited patent lifetimes, the need to get a return on the investment in research and gain competitive advantage by launching products before competitors all contribute to the necessity to get products to market. The ability of biosensor technology to give rapid, direct information on key biological parameters, (such as product concentration), makes it a suitable analytical tool to help accelerate the development of biological products. It is difficult to conceive how direct measurements of this speed and selectivity can be possible with other analytical methods. This paper aims to describe how this potential can be brought to use from biological product conception and discovery all the way through to process operation and quality control.     

Process modeling and simulation can guide process development: case study α-cyclodextrin

Modeling and simulation of biotechnological processes enables the quantification of possible process variations. In this way it provides a tool for guiding research towards the most promising directions. The method is shown on the basis of the case study of α-cyclodextrin production. The production process was modeled and the model is used to evaluate the potential impact of CGTases with new properties. Sensitivity analyses show that yield and selectivity are the crucial parameters. Reaction time has only limited impact and substrate concentration has to be above 20%. The use of thermostable enzymes provides some energy savings. Furthermore, the effect of new CGTases leading to a modified downstream processing was assessed.     

我国生物技术基地平台现状与发展建议

生物技术是21世纪以来新一轮科技革命和产业变革的核心,而生物技术基地平台是开展生物技术研究、生产和服务的载体,是生物技术创新体系的重要组成部分。对世界主要发达国家及我国生物技术基地平台的总体规模和建设情况进行梳理分析,并借鉴国外经验,提出改进我国生物技术基地平台建设的政策建议,以供参考。     

“一带一路”沿线国家生物技术发展趋势研究

“一带一路”贯穿亚欧非大陆,联结活跃的东亚经济圈和发达的欧洲经济圈,以及中间经济发展潜力巨大的广大腹地国家与地区,“一带一路”战略将对中国未来国内外的政治、经济、文化、科技发展产生重大深远影响。本报告分析了“一带一路”沿线国家的科技发展基础条件,研究了“一带一路”沿线国家在生物技术领域取得的基础研究进展和专利技术研发进展的总体情况,综述了“一带一路”沿线国家生物技术产业发展现状和国际专利布局情况,并针对中国与“一带一路”沿线国家在生物技术领域进一步深化合作互利共赢提出了发展建议。     

生物技术在我国渔业中的应用

论述了近十几年来我国渔业生物技术的研究进展及应用成果。主要内容有基因工程、细胞工程、发酵工程、酶工程在我国渔业中的研究、应用情况。     

国外生物技术产业发展政策研究

全球生物技术产业尚处于发展时期,政府的政策对技术的进步和产业的发展有明显的导向和促进作用。对美国、欧洲等国家和地区的产业政策进行综合研究,发现这些生物技术产业相对发达的国家和地区,尤其是美国,其产业政策已成体系,而且可操作性强,对产业的推动作用明显,具有相当的可借鉴意义。从组织管理结构、科研投入机制、鼓励研发创新、财税支持方式、资本市场培育、产业基地建设、中介服务网络构建、人才培养与引进、以及国际合作等方面对国际上行之有效的生物技术产业政策进行了归纳分析 。     

基于生产工艺管理的生物工程综合性实验设计

生物工程综合性实验课程以企业人才需求为导向,解决实际生产过程中的复杂工程问题为教学目标,利用两步酶转化法制备L-天冬氨酸和L-丙氨酸的工艺路线,结合生物工程专业生产工艺管理的特点,借鉴生产企业现场管理经验,实施四班三运转的实验运行方式。成绩考核加入交接班总结评价与团队协作评价,该课程设置了包含多门专业核心课程原理、方法与实验技术和企业生产管理模式的新型生物工程综合性实验教学内容,并通过教学实践,持续改进,形成完整的实验教学过程与考核机制。生物工程综合性实验课程取得了良好的教学效果,促进了生物工程专业实验教学的发展。     

Biotechnology in schools: The UK experience

Biotechnology has gained a significant presence in shcool teaching in the United Kingdom over the past decade. This process has been encouraged by some centrally funded initiatives, but has also been due to the efforts of several independent individuals and groups who have recognized the need to focus on this burgeoning area of scientific research and development, and the contribution that it can make to enlivening the curriculum. Developments in the UK have both benefited from and contributed to similar projects overseas. Biotechnology is set to become increasingly prominent in socio-economic terms for the foreseeable future. It is vital that this is reflected in our educational system and that the preliminary work in this respect is allowed to evolve concurrently.