捷安肽素高产突变株96孔板筛选方法的建立

建立了一种快速灵敏地筛选出捷安肽素(JAA)高产突变株的方法。主要利用96多孔板固体培养菌体,用50%乙醇为最佳浸提液浸提4h,滤纸片法检测JAA生物活性的点样量为100μL,筛选出5株高产突变株,经摇瓶复筛选出2株高产突变株,经一剂量法检测,其抑菌圈直径较出发菌株提高了14%左右。     

Evaluation of filter paper collection of urine samples for detection and measurement of organic acidurias by capillary electrophoresis

There is little doubt that mental retardation has been prevented in most babies diagnosed by newborn screening programs for inborn errors and the cost-benefit ratios of these programs have been reported as highly positive. In a previous work we optimised a CE method for quick profiling of organic acidurias, which characterize a large number of inborn errors, so that it permits the separation, detection and even identification in less than 15 min of 22 organic acids in urine samples related to a wide range of metabolic disorders. In the present work we have studied the adequacy of filter paper collection of urine samples to simplify this step, always difficult in babies, when it is not performed by training personnel. The studied parameters were: media and conditions for re-extraction to give the best sensitivity and a more simple procedure when the samples are measured by CE, interferences coming from the diaper, recoveries obtained, possible correction of recoveries with creatinine and stability of the compounds. The whole method we report has the advantages of easy sample collection, easy shipping or delivery, and rapid analysis. Moreover, this method of collection and analysis allows the identification and quantitation of fumaric, methylmalonic, N-acetylaspartic, pyroglutamic and homogentisic acids, as well as glutaric acid for which screening is considered especially advisable.     

Agreement between spatiotemporal parameters from a photoelectric system with different filter settings and high-speed video analysis during running on a treadmill at comfortable velocity

The aim of this study was to determine the level of agreement between spatiotemporal gait characteristics from a photoelectric system with different filter settings and high-speed video analysis during running on a treadmill at comfortable velocity. Forty-nine runners performed a running protocol on a treadmill at comfortable velocity. Two systems were used to determine spatiotemporal parameters (i.e. contact time [CT], flight time [FT], step frequency [SF] and step length [SL]) during running: OptoGait system and high-speed video analysis at 1000 Hz. The collected data was re-filtered in the OptoGait software by using nine different settings (i.e. 0_0, 1_1, 2_2, 3_3, 3_4, 4_4, 4_5, 5_4 and 5_5), and compared to those obtained through video analysis. The Pearson correlation analysis revealed very large correlations (r > 0.9, p < 0.001) in CT, FT, SF and SL between both systems, regardless of the OptoGait’s filter settings. The ICC reported an almost perfect association (ICC > 0.9) for both SL and SF regardless of the filter setting. However, large variations between filter settings according to the data from video analysis were reported in CT and FT (0_0, 1_1 and 2_2 filter settings obtained an association ICC > 0.9, whereas other filters obtained lower ICCs). Bland-Altman plots revealed small bias and error and no presence of heteroscedasticity of error for 1_1 setting. In conclusion, the filter setting for the OptoGait system should be considered to minimize the bias and error of spatiotemporal parameters measurement. For running on a treadmill, the 1_1 filter setting is recommended if gait parameters are to be compared to a high-speed video analysis (1000 Hz).     

A high‐throughput sample preparation method for cellular proteomics using 96‐well filter plates

A high‐throughput sample preparation protocol based on the use of 96‐well molecular weight cutoff (MWCO) filter plates was developed for shotgun proteomics of cell lysates. All sample preparation steps, including cell lysis, buffer exchange, protein denaturation, reduction, alkylation and proteolytic digestion are performed in a 96‐well plate format, making the platform extremely well suited for processing large numbers of samples and directly compatible with functional assays for cellular proteomics. In addition, the usage of a single plate for all sample preparation steps following cell lysis reduces potential samples losses and allows for automation. The MWCO filter also enables sample concentration, thereby increasing the overall sensitivity, and implementation of washing steps involving organic solvents, for example, to remove cell membranes constituents. The optimized protocol allowed for higher throughput with improved sensitivity in terms of the number of identified cellular proteins when compared to an established protocol employing gel‐filtration columns.     

Rosette Colonies of Choanoflagellates (Salpingoeca rosetta) Show Increased Food Vacuole Formation Compared with Single Swimming Cells

Choanoflagellates exist as both single‐celled and colonial forms and filter‐feed by generating water currents using a single apical flagellum. Hydrodynamic modeling studies have differed in predictions of whether single cells or colonies produce greater fluid flow to enhance feeding, and a recent study reported no increase in feeding efficiency of stalked colonies of choanoflagellates compared with single cells. We report that rosette colonies of Salpingoeca rosetta demonstrate higher rates of food vacuole formation compared with unicellular, slow swimmers.     

Case studies on the use of biotechnologies and on biosafety provisions in four African countries

This review is based on a study commissioned by the European Commission on the evaluation of scientific, technical and institutional challenges, priorities and bottlenecks for biotechnologies and regional harmonisation of biosafety in Africa. Biotechnology was considered within four domains: agricultural biotechnologies (‘Green’), industrial biotechnologies and biotechnologies for environmental remediation (‘White’), biotechnologies in aquaculture (‘Blue’) and biotechnologies for healthcare (‘Red’). An important consideration was the decline in partnerships between the EU and developing countries because of the original public antipathy to some green biotechnologies, particularly genetically modified organisms (GMOs) and food from GM crops in Europe. The study focus reported here was West Africa (Ghana, Senegal, Mali and Burkina Faso).The overall conclusion was that whereas high-quality research was proceeding in the countries visited, funding is not sustained and there is little evidence of practical application of biotechnology and benefit to farmers and the wider community. Research and development that was being carried out on genetically modified crop varieties was concentrating on improving food security and therefore unlikely to have significant impact on EU markets and consumers. However, there is much non-controversial green biotechnology such as molecular diagnostics for plant and animal disease and marker-assisted selection for breeding that has great potential application. Regarding white biotechnology, it is currently occupying only a very small industrial niche in West Africa, basically in the sole sector of the production of liquid biofuels (i.e., bio-ethanol) from indigenous and locally planted biomass (very often non-food crops). The presence of diffused small-scale fish production is the basis to develop and apply new (Blue) aquaculture technologies and, where the research conditions and the production sector can permit, to increase this type of production and the economy of this depressed areas. However, the problems bound to environmental protection must not be forgotten; priority should be given to monitor the risks of introduction of foreign species. Red biotechnologies potentially bring a vast domain of powerful tools and processes to achieve better human health, most notably improved diagnostics by molecular techniques, better targeting of pathogens and a better knowledge of their sensitivities to drugs to permit better treatment.Biosafety regulatory frameworks had been initiated in several countries, starting with primary biosafety law. However, disparate attitudes to the purpose of biosafety regulation (e.g., fostering informed decision-making versus ‘giving the green-light for a flood of GMOs’) currently prevent a needed consensus for sub-regional harmonisation. To date, most R&D funding has come from North America with some commercial interests from Asia, but African biotechnology workers expressed strong desire for (re-)engagement with interested parties from the European Union. Although in some of the visited countries there are very well qualified personnel in molecular biology and biosafety/regulation, the main message received is that human resources and capacity building in-house are still needed. This could be achieved through home-based courses and capacity-building including funds for post-degree research to motivate and retain trained staff.     

产业化案例辅助“酶工程”理论教学的探讨

介绍对生物技术和生物工程专业高年级学生开设的“酶工程”课程在教学内容、教学方法等方面的改革。采取产业化案例辅助理论教学的全新授课模式, 主要包括教材和授课内容体现工程特色、产业化案例辅助章节理论和整个课程体系教学、学生参与课堂互动教学等方面。通过教学改革, 收到较好的授课效果。     

Identification and characterization of functional aquaporin water channel protein from alimentary tract of whitefly, Bemisia tabaci

Some hemipteran xylem and phloem-feeding insects have evolved specialized alimentary structures or filter chambers that rapidly transport water for excretion or osmoregulation. In the whitefly, Bemisia tabaci, mass movement of water through opposing alimentary tract tissues within the filter chamber is likely facilitated by an aquaporin protein. B. tabaci aquaporin-1 (BtAQP1) possesses characteristic aquaporin topology and conserved pore-forming residues found in water-specific aquaporins. As predicted for an integral transmembrane protein, recombinant BtAQP1 expressed in cultured insect cells localized within the plasma membrane. BtAQP1 is primarily expressed in early instar nymphs and adults, where in adults it is localized in the filter chamber and hindgut. Xenopus oocytes expressing BtAQP1 were water permeable and mercury-sensitive, both characteristics of classical water-specific aquaporins. These data support the hypothesis that BtAQP1 is a water transport protein within the specialized filter chamber of the alimentary tract and functions to translocate water across tissues for maintenance of osmotic pressure and/or excretion of excess dietary fluid.