遗传物质的横向传递与转基因植物的安全性

横向传递是在同种或异种生物不同个体之间沿水平方向进行遗传物质的单方向转移,有多种不同的转移方式。在生物界中,遗传物质的横向传递通常是借助某种载体如病毒来完成,高等生物还可以通过有性生殖在同种生物不同个体之间或异种生物不同个体之间传递遗传物质。基因的横向传递是普遍存在的,是生物进化的重要动力之一。转基因植物是人工遗传物质横向转移的结果,人工遗传物质横向转移正在越来越明显地影响着生物的生存状态。     

Particle Erosion Resistance of Bionic Samples Inspired from Skin Structure of Desert Lizard, Laudakin stoliczkana

In order to improve the particle erosion resistance of engineering surfaces,this paper proposed a bionic sample which is inspired from the skin structure of desert lizard,Laudakin stoliczkana.The bionic sample consists of a hard shell (aluminum) and a soft core (silicone rubber) which form a two-layer composite structure.The sand blast tests indicated that the bionic sample has better particle erosion resistance.In steady erosion period,the weight loss per unit time of the bionic sample is about 10％ smaller than the contrast sample.The anti-erosion mechanism of the bionic sample was studied by single particle impact test.The results show that,after the impact,the kinetic energy of the particle is reduced by 56.5％ on the bionic sample which is higher than that on the contrast sample (31.2％).That means the bionic sample can partly convert the kinetic energy of the particle into the deformation energy of the silicone rubber layer,thus the erosion is reduced.     

Secondary transport as an efficient membrane transport mechanism for plant secondary metabolites

Plants produce a large number of secondary metabolites, such as alkaloids, terpenoids, and phenolic compounds. Secondary metabolites have various functions including protection against pathogens and UV light in plants, and have been used as natural medicines for humans utilizing their diverse biological activities. Many of these natural compounds are accumulated in a particular compartment such as vacuoles, and some are even translocated from source cells to sink organs via long distance transport. Both primary and secondary transporters are involved in such compartmentation and translocation, and many transporter genes, especially genes belonging to the multidrug and toxin extrusion type transporter family, which consists of 56 members in Arabidopsis, have been identified as responsible for the membrane transport of secondary metabolites. Better understandings of these transporters as well as the biosynthetic genes of secondary metabolites will be important for metabolic engineering aiming to increase the production of commercially valuable secondary metabolites in plant cells.     

热稳定型α-半乳糖苷酶的应用及基因工程研究进展

α-半乳糖苷酶是一种水解酶,可以将食品、饲料中的不良寡糖等抗营养因子水解,改变其营养成分并被动物吸收利用。该酶广泛存在于植物、动物及微生物中,在饲料、食品等工业以及现代医学中都有应用。目前,开发热稳定的α-半乳糖苷酶并利用基因工程方法进行分子改造和外源表达已成为研究热点。本文对近年来热稳定的α-半乳糖苷酶的应用和基因工程研究进展进行综述。     

Bionic Photovoltaic Panels Bio-Inspired by Green Leaves

In strong solar light, silicon solar panels can heat up by 70℃ and, thereby, loose approximately one third of their efficiencyfor electricity generation. Leaf structures of plants on the other hand, have developed a series of technological adaptations,which allow them to limit their temperature to 40-45℃ in full sunlight, even if water evaporation is suppressed. This is accomplishedby several strategies such as limitation of leaf size, optimization of aerodynamics in wind, limitation of absorbedsolar energy only to the useful fraction of radiation and by efficient thermal emission. Optical and infrared thermographicmeasurements under a solar simulator and in a streaming channel were used to investigate the corresponding properties of leavesand to identify suitable bionic model systems. Experiments started with the serrated structure of ordinary green leaves distributedover typical twig structures and finally identified the Australian palm tree Licuala ramsayi as a more useful bionic model. Itcombines a large area for solar energy harvesting with optimized aerodynamic properties for cooling and is able to restructureitself as a protection against strong winds. The bionic models, which were constructed and built, are analyzed and discussed.     

DEM Simulation of Clod Crushing by Bionic Bulldozing Plate

Through evolving over millions of years, earthworm has developed the typical wavy body surface. The non-smooth surface shape can break the clods into small pieces, which is one of the important reasons to make earthworm move freely in soil. Based on engineering bionics, the non-smooth body surface of earthworm was regarded as the bionic prototype, and a bionic wavy plane bulldozing plate was designed. In order to analyze the clod crushing mechanism by the bionic bulldozing plate, the nonlinear mechanical model of contact between soil particles was established and the clod-crushing processes by the bionic bulldozing plate and the smooth bulldozing plate were simulated by Distinct Element Method (DEM). Simulation results indicate that the bionic bulldozing plate has stronger clod-crushing ability and can break much more clods than the smooth bulldozing plate can.     

Sounds Synthesis with Slime Mould of Physarum Polycephalum

This paper introduces a novel application of bionic engineering: a bionic musical instrument using Physarum polycephalum. Physarum polycephalum is a huge single cell with thousands of nuclei, which behaves like a giant amoeba. During its foraging behavior this plasmodium produces electrical activity corresponding to different physiological states. We developed a method to render sounds from such electrical activity and thus represent spatio-temporal behavior of slime mould in a form apprehended auditorily. The electrical activity is captured by various electrodes placed on a Petri dish containing the cultured slime mold. Sounds are synthesized by a bank of parallel sinusoidal oscillators connected to the electrodes. Each electrode is responsible for one partial of the spectrum of the resulting sound. The behavior of the slime mould can be controlled to produce different timbres.     

植物甜菜碱合成途径及基因工程研究进展

甜菜碱是公认的在细胞中起着无毒渗透保护作用的细胞相溶性物质 ,广泛存在于植物、动物、细菌等多种生物体中。植物中甜菜碱因其结构不同 ,其生物合成途径和催化合成所需要的酶也各不相同。综述了近年来甜菜碱生物合成途径、相关基因的克隆及基因工程研究进展 ,包括从不同生物体中克隆、鉴定的甜菜碱合成的相关基因及其定位、作用机理、同源性比较及表达差异、在转基因植物中的遗传稳定性以及转基因植物的抗盐耐旱、抗寒性等。     

骨组织工程血管化的研究进展

血管化是组织工程骨成活的关键,组织工程骨的血管化过程与生理情况下的血管发生相似,但又有其独特性,并受多种因素影响。基于对组织工程骨血管化过程的认识,研究者通过联合细胞培养、促血管化生长因子、显微外科等方法重建血运。本文综述了当前骨组织工程的血管化研究进展。     

Mechanism Interpretation of the Biological Brain Cooling and Its Inspiration on Bionic Engineering

The brain is one of the most important organs in a biological body which can only work in a relatively stable temperature range. However, many environmental factors in biosphere would cause cerebral temperature fluctuations. To sustain and regulate the brain temperature, many mechanisms of biological brain cooling have been evolved, including Selective Brain Cooling (SBC), cooling through surface water evaporation, respiration, behavior response and using special anatomical appendages. This article is dedicated to present a summarization and systematic interpretation on brain cooling strategies developed in animals by classifying and comparatively analyzing each typical biological brain cooling mechanism from the perspective of bio-heat transfer. Meanwhile, inspirations from such cooling in nature were proposed for developing advanced bionic engineering technologies especially with two focuses on therapeutic hypothermia and computer chip cooling areas. It is expected that many innovations can be achieved along this way to find out new cooling methodologies for a wide variety of industrial applications which will be highly efficient, energy saving, flexible or even intelligent.     

Towards microbial tissue engineering?

Tissue engineering involves the creation of multicellular tissues from individual cells. It was previously perceived that tissues were only formed by higher organisms such as plants and animals. However, it is now known that multicellular systems of microorganisms, such as microbial colonies, biofilms, flocs and aggregates, can also show extensive spatial organization. Here, we discuss methods that can be used to spatially organize microorganisms--bacteria, in particular--into tissue-like materials with defined internal architectures. Some potential uses of such "microbial tissues" are covered.     

Biotechnology-a sustainable alternative for chemical industry

This review outlines the current and emerging applications of biotechnology, particularly in the production and processing of chemicals, for sustainable development. Biotechnology is “the application of scientific and engineering principles to the processing of materials by biological agents”. Some of the defining technologies of modern biotechnology include genetic engineering; culture of recombinant microorganisms, cells of animals and plants; metabolic engineering; hybridoma technology; bioelectronics; nanobiotechnology; protein engineering; transgenic animals and plants; tissue and organ engineering; immunological assays; genomics and proteomics; bioseparations and bioreactor technologies. Environmental and economic benefits that biotechnology can offer in manufacturing, monitoring and waste management are highlighted. These benefits include the following: greatly reduced dependence on nonrenewable fuels and other resources; reduced potential for pollution of industrial processes and products; ability to safely destroy accumulated pollutants for remediation of the environment; improved economics of production; and sustainable production of existing and novel products.     

A Biological Coupling Extension Model and Coupling Element Identification

Extenics is a newly developed interdisciplinary subject combining mathematics, philosophy and engineering. It providesuseful formalized qualitative tools and quantitative tools for solving contradictory problems. In this paper, extension theory isintroduced briefly and the primary applications of this theory and methods in bionic engineering research are discussed. Theextension model of biological coupling functional system is established. In order to identify the primary and secondary sequencingof coupling elements, the Extension Analytic Hierarchy Process (EAHP) was adopted to analyze the contribution ofeach coupling element to the coupling functional system. Thus, the influence weight factor of each coupling element can bedetermined, so as to provide a new approach for solving primary and secondary sequencing problem of coupling elements in aquantitative way, and facilitate the subsequent bionic coupling study.     

Plants intertwine fluvial landform dynamics with ecological succession and natural selection: a niche construction perspective for riparian systems

Aim   To contribute to the development of a macroevolutionary framework for riparian systems, reinforcing conceptual linkages between earth surface processes and biological and ecological processes.
Location   Riparian systems.
Methods   Literature review leading to an original proposition for perceiving the functioning of riparian systems in a new and different way.
Results   Riparian systems provide diverse landforms, habitats and resources for animals and plants. Certain organisms, defined as 'ecosystem engineers', significantly create and modify the physical components of riparian systems. Many studies have highlighted such engineering effects by animals on riparian systems, but the identification and understanding of the effects and responses of plants within fluvial corridors have emerged only recently. The modulation of matter, resources and energy flows by engineering plants helps establish characteristic sequences of fluvial landform creation and maintenance associated with synergetic ecological successions. We relate this process to the concept of niche construction, developed mainly by evolutionary biologists. Feedbacks between adaptive responses of riparian plants to flow regime and adjusting effects on biostabilization and bioconstruction are discussed in the context of niche construction at the scale of ecological succession and the evolution of organisms.
Main conclusions   Our conceptualization forges an integrated approach for understanding vegetated fluvial systems from a macroevolutionary perspective, for elucidating riparian ecosystem dynamics and potentially for establishing long-term stream conservation and restoration strategies.     

Carotenoid biotechnology in plants for nutritionally improved foods

Carotenoids participate in light harvesting and are essential for photoprotection in photosynthetic plant tissues. They also furnish non-photosynthetic flowers and fruits with yellow to red colors to attract animals for pollination and dispersal of seeds. Although animals can not synthesize carotenoids de novo , carotenoid-derived products such as retinoids (including vitamin A) are required as visual pigments and signaling molecules. Dietary carotenoids also provide health benefits based on their antioxidant properties. The main pathway for carotenoid biosynthesis in plants and microorganisms has been virtually elucidated in recent years, and some of the identified biosynthetic genes have been successfully used in metabolic engineering approaches to overproduce carotenoids of interest in plants. Alternative approaches that enhance the metabolic flux to carotenoids by upregulating the production of their isoprenoid precursors or interfere with light-mediated regulation of carotenogenesis have been recently shown to result in increased carotenoid levels. Despite spectacular achievements in the metabolic engineering of plant carotenogenesis, much work is still ahead to better understand the regulation of carotenoid biosynthesis and accumulation in plant cells. New genetic and genomic approaches are now in progress to identify regulatory factors that might significantly contribute to improve the nutritional value of plant-derived foods by increasing their carotenoid levels.     

Nutritious crops producing multiple carotenoids--a metabolic balancing act

Plants and microbes produce multiple carotenoid pigments with important nutritional roles in animals. By unraveling the basis of carotenoid biosynthesis it has become possible to modulate the key metabolic steps in plants and thus increase the nutritional value of staple crops, such as rice (Oryza sativa), maize (Zea mays) and potato (Solanum tuberosum). Multigene engineering has been used to modify three different metabolic pathways simultaneously, producing maize seeds with higher levels of carotenoids, folate and ascorbate. This strategy may allow the development of nutritionally enhanced staples providing adequate amounts of several unrelated nutrients. By focusing on different steps in the carotenoid biosynthesis pathway, it is also possible to generate plants with enhanced levels of several nutritionally-beneficial carotenoid molecules simultaneously.     

Biosynthesis and genetic engineering of proanthocyanidins and (iso)flavonoids

Plant natural products have been used since ancient times as medicines and herbal remedies. Over the past two decades, the results of population and intervention studies, or assays in animal or cell model systems, have revealed positive health beneficial effects for various classes of phytochemicals, particularly polyphenols. The results of such studies have ignited an interest in being able to manipulate the levels of such bioactive compounds in plants using biotechnological approaches. Although still in its infancy, this technology promises to deliver health benefits to humans and animals through direct consumption of genetically-modified or -enhanced dietary plant materials. We here review the strategies currently being used for engineering two classes of nutraceuticals, the proanthocyanidins and the isoflavones, in transgenic plants. We also provide an overview of recent advances in our understanding of the biosynthesis of these classes of compounds.     

Design Principles of the Non-smooth Surface of Bionic Plow Moldboard

1　IntroductionTransferringbiologyfunctiontoengineeringtech nology[1] isaprominentprogressintechnologicalfields ,whichenrichesthecontentofTRIZsystematicmethod .Thenon smoothsurfacesofthetypicalsoilan imalshavetheeffectsofreducingsoiladhesion ,whichhasbeenconvincedandgraduallyaccepted .Thebionicplowmoldboardisanappliedexampleofimitatingthecharacteristicsofsoilanimals’surfaceappearancesandpracticingtheBionicTheoryofNon SmoothSurface(TNSS) .ThebasisofTNSSisnon smoothsurfaceef fects[2 ,3] …     

The limits and frontiers of desiccation-tolerant life

Drying to equilibrium with the air is lethal to most speciesof animals and plants, making drought (i.e., low external waterpotential) a central problem for terrestrial life and a majorcause of agronomic failure and human famine. Surprisingly, awide taxonomic variety of animals, microbes, and plants do toleratecomplete desiccation, defined as water content below 0.1 g H₂Og^–1 dry mass. Species in five phyla of animals and fourdivisions of plants contain desiccation-tolerant adults, juveniles,seeds, or spores. There seem to be few inherent limits on desiccationtolerance, since tolerant organisms can survive extremely intenseand prolonged desiccation. There seems to be little phylogeneticlimitation of tolerance in plants but may be more in animals.Physical constraints may restrict tolerance of animals withoutrigid skeletons and to plants shorter than 3 m. Physiologicalconstraints on tolerance in plants may include control by hormoneswith multiple effects that could link tolerance to slow growth.Tolerance tends to be lower in organisms from wetter habitats,and there may be selection against tolerance when water availabilityis high. Our current knowledge of limits to tolerance suggeststhat they pose few obstacles to engineering tolerance in prokaryotesand in isolated cells and tissues, and there has already beenmuch success on this scientific frontier of desiccation tolerance.However, physical and physiological constraints and perhapsother limits may explain the lack of success in extending toleranceto whole, desiccation-sensitive, multicellular animals and plants.Deeper understanding of the limits to desiccation tolerancein living things may be needed to cross this next frontier.