Table of Content

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• Current Biotechnology
  Volume 2 Issue 4 25 July 2012
• Recent Advances in the Rational Design to Improve the Protein Thermostability
• TIAN Jian, WANG Ping, WU Ning-feng, FAN Yun-liu
• 2012, 2(4):  233-239.  DOI: 10.3969/j.issn.2095-2341.2012.04.01
• Abstract ( ) PDF (1215KB)( )
The studies on the rational design methods for improving the protein thermalstability were the hotspots in the field of computational biology and protein engineering. Compared to the traditional methods for enhancing the protein thermostability, rational design methods had many advantages, such as high efficiency and strong purposes. Moreover, the methods could not only expand the application scope of enzymes, but also help us to understand the relationship between protein structure and its function. In this paper, we introduced some factors that related to the protein thermostability and strategies usually used to improve the protein thermostability in detail. However, there were many factors that could affect the thermalstability of proteins, and there were many intricate links among these factors. So far, the researchers did not yet propose a rational design strategy that could adapt to all proteins. But it was an important direction that need the computing biologists and protein engineering scientists to study.
• Progress on Application of Drought-resistance Genes in Tobacco
• ZHAO Wen-jun, YANG Ji-zhou, HU Bao-wen, CHANG Jian
• 2012, 2(4):  240-248.  DOI: 10.3969/j.issn.2095-2341.2012.04.02
• Abstract ( ) PDF (1168KB)( )
Drought is one of the most important stress factors influencing the growth, development, yield and quality in tobacco. Several droughtresistance related genes can be triggered to improve drought tolerance when the plants suffer from drought stress. Many droughtresistance related functional and regulatory genes had been cloned and integrated into tobacco genome by genetic engineering method. Droughtresistance ability is improved due to the expression of foreign droughtresistance related genes in transgenic tobacco. Cloning of droughtresistance gene lays the molecular foundation for breeding droughtresistance cultivars. Systematic study on expression and regulation of droughtresistance related genes under drought stress can provide a new approach for improving droughtresistance in tobacco as well as providing genetic resources for droughtresistant breeding and variety improvement in other crops.
• The Application Prospect of RNAi Technology in Animal Breeding for Disease Resistance
• YE Ming-qiang, KUANG Zhe-shi, ZHAO Xiang-jie, WU Fu-quan, LI Qing-rong, XIAO Yang, LUO Guo-qing*
• 2012, 2(4):  249-254.  DOI: 10.3969/j.issn.2095-2341.2012.04.03
• Abstract ( ) PDF (1119KB)( )
Viruses are serious threats to human and animal health. Vaccines can prevent viral diseases, but few antiviral treatments are available to control evolving infections. Though it is only more than ten years since RNA interference (RNAi) has been discovered, we have had a clear picture of RNAi mechanism. RNAi is an effective means of suppressing virus replication in vitro, the progress has been achieved in studies of RNA interference mediated transgenic animals resistant to disease. At present, genetically modified sheep and cattle resistant to prion prote, as well as pig resistant to porcine endogenous retrovirus (PERV) and silkworm resistant to nuclear polyhedrosis virus (NPV) have been achieved. Though most RNAi researches focus on cell lines and the available species of transgenic animals is limited, these researches provide a valid basis for the continued production of disease resistant transgenic animals. With the progress of transgenic technology, RNAi mediated transgenic breeding for disease resistance should be the most promising methods of reducing animal infectious diseases in the future.
• The Comparison of Development Biological Changes Between Normal Embryos and Nuclear Transfer Embryo
• SUI Jin-qiang, GAO Wen-chao, ZUO Xiu-he, LEI An-min*
• 2012, 2(4):  255-262.  DOI: 10.3969/j.issn.2095-2341.2012.04.04
• Abstract ( ) PDF (1133KB)( )
In this paper, we introduced biological morphological change during development of normal embryos and cloned embryos, elaborated the difference from the morphological and molecular mechanism between the two, and summed up the main factors which impact the development of reconstruction of nuclear transfer embryos. Moreover, we disscussed morphology in the cells focused on chromosome structural changes to the effect of egg reprogramming, at the molecular level the replacement between the egg histone and the cell histone, in theory, to provide a reference to improve the efficiency of nuclear transfer.
• Research Progress in Macrocyclic Compounds of Secondary Metabolites from Myxobacteria
• HUANG Yan, HU Jian-wei, ZHU Hong-hui
• 2012, 2(4):  263-269.  DOI: 10.3969/j.issn.2095-2341.2012.04.05
• Abstract ( ) PDF (1204KB)( )
Myxobacteria can produce various secondary metabolites, and hence are considered as the third group of bacteria producing secondary metabolites following Actinomyces and Bacillus. This paper presents the research advance in macrocyclic compounds of secondary metabolites from myxobacteria. This paper introduces the major kinds of macrocyclic compounds, their structure and myxobacteria strains from which they were isolated, summarizes the bioactivities from the aspects of anti-tumor, anti-bacteria, anti-fungi, and anti-virus etc, and puts forward the related researches on macrocyclic compounds of secondary metabolites from myxobacteria.
• Study on Genetic Divergence of Hainan Common Wild Rice (Oraza rufipogon) Based on ITS Analysis
• YIN Zhao-kun, LIAO Cheng-hong, XU Li-xin, PEI Xin-wu, YUAN Qian-hua
• 2012, 2(4):  270-275.  DOI: 10.3969/j.issn.2095-2341.2012.04.06
• Abstract ( ) PDF (1126KB)( )
Eighteen individual samples of common wild rice (Oryza rufipogon Griff.) from Hainan were used for cloning and sequencing. Sequence analysis showed significant differences in ITS sequence among these populations. The results indicated that these populations had a genetic relationship, a total of 108 polymorphic fragments were detected in ITS1, and 145 polymorphic fragments in ITS2. Besides, there were 133 InDels in ITS1, 145 InDels in ITS2. It indicated that the common wild rice from Hainan performed some Indica-Japonica differentiations, more Indica than Japonica types, and 9 ITS Indica-Japonica differentiations sites were found. This work will help to understand the status of Oraza ruffipogon from Hainan in the origin and evolution of the cultivated rice in China, and also offer reference for potential use of the wild rice from Hainan.
• The Comparative Study on Stress Resistance of two Trifolium Varieties at the Germination Period and the Seeding Stage
• LIU Xiao-shan
• 2012, 2(4):  276-281.  DOI: 10.3969/j.issn.2095-2341.2012.04.07
• Abstract ( ) PDF (1110KB)( )
The paper studies the stress resistance of two Trifolium varieties(Trifolium hybridum L. and T. subterraneum L.)under different conditions of environmental stress. The result indicated that, under the stress of different salinities processing, the chlorophyll content of Trifolium reduces with the salinity increase, the tissue water content has no obvious change, the content of free-proline increases with the salinity increase, the permeability of cell membrane in leaf blade goes up with the salinity increase. Under different water regimes, the permeability of cell membrane and the content of free-proline of Trifolium increases along with the moisture content increase, the chlorophyll content and the tissue water content have no obvious change. Under different illu mination schemes, the chlorophyll content, the tissue water content and the content of free-proline of Trifolium have no obvious change, the permeability of cell membrane reduces with the daylight length increase. Under the stress of different temperature, the chlorophyll content, the tissue water content and the content of free-proline of Trifolium have no obvious change, the permeability of cell membrane reduces with the temperature increase. Otherwise，the stress resistance of T. hybridum L. is better than that of T. subterraneum L.
• Cloning and Prokaryotic Expression of the S Gene Segment of Porcine Epidemic Diarrhea Virus
• WANG Shu-kun, LANG Hong-wu, LI Yi-nv, CHEN Xiao-chun, ZHANG Zhi-fang
• 2012, 2(4):  282-287.  DOI: 10.3969/j.issn.2095-2341.2012.04.08
• Abstract ( ) PDF (1352KB)( )
In order to study the antigenicity of prokaryotic expression of the S gene segment of porcine epidemic diarrhea virus (PEDV), its antigen site was analyzed, and the segment was amplified with PCR. Then we constructed the recombinant with the vector pET-28a(+) named pET-28a-PEDV-Sp, which was induced to express in E.coli BL21(DE3) by 0.5 mmol/L IPTG at 37℃. Futhermore, the expressed product was analysed by SDS-PAGE, and the result indicated that there was a new 29 kDa-electrophoretic band corresponding to the presumptive interested protein. In addition, the result of mass spectrometry also showed that the recombinant protein was expressed successfully. The purified protein was then used for preparation of polyclonal antibody. The result of ELISA showed the protein had good antigenicity. This work lays a foundation for the development of genetic engineering vaccine of PEDV.
• Research on Extraction Process for Cyclic Adenosine Monophosphate(cAMP) in Jujubes by Ion Exchange
• XIA Quan-ming1,2, ZHOU Yang1, ZHAO Li-ming1,2*, ZHOU Jia-chun1,2, JIANG Li-hua1,2, ZHAO He-fei2
• 2012, 2(4):  288-292.  DOI: 10.3969/j.issn.2095-2341.2012.04.09
• Abstract ( ) PDF (1341KB)( )
Cyclic adenosine-3′,5′-monophosphate (cAMP) is one of the most important physiological active substances as the second messenger for regulating physiological and biochemical processes. Water extraction and 6 000 Da ultrafiltration method were used for pretreatment. The most suitable one was selected from 5 types of resins and the extraction process was optimized. Results showed that the optimal pretreatment condition for jujubes is that 12 hours water extraction at 60℃ with small granular (0.3 cm) broken state. By comparing SD5, SD8, D01, D05 and D13 ion exchange resins, D13 was found to be the most suitable one for cAMP extraction. 0.05 mol/L HCl were selected as eluting agent at the flow rate of 1.5 mL/min. The product yield was 65% while the cAMP concentration was 37.5%.
• A Simple and Effective Method for Genomic DNA Extraction from Yeasts
• TANG Qiao-ling, FU Peng-fei, WANG Xu-jing, WANG Zhi-xing
• 2012, 2(4):  293-296.  DOI: 10.3969/j.issn.2095-2341.2012.04.10
• Abstract ( ) PDF (1297KB)( )
Extraction genomic DNA from yeasts for some assays is very important. Yeast-lysis solution contained 0.2 mol/L lithium acetate, 1% SDS and other components can efficiently lysis Pichia pastoris GS115 cells. In comparison with two kinds of yeast genomic DNA extraction kits, the amount of genomic DNA extracted by this way was more than five times as much as those by the kits from same volume liquid culture. Moreover, the genomic DNA extraction protocol set up in the paper was simple and easy to perform. It took 2 hours to finish a whole protocol. To further test the quality of genomic DNA, PCR amplification and Southern blot analysis of AOX gene in yeast genomic DNA were done. Therefore, we have developed a quick, lowcost and effective genomic DNA extraction protocol from yeast cells in this paper.
• Argentina Agricultural Biotechnology Annual (2011)
• Andrea Yankelevich, David Mergen*
• 2012, 2(4):  297-303.  DOI: 10.3969/j.issn.2095-2341.2012.04.11
• Abstract ( ) PDF (1702KB)( )
Argentina continues to be the third largest producer of biotech crops after the United States and Brazil, producing 15 percent of the world s biotech production. On May 19, 2011, the government approved Syngenta s corn event MIR162 for production and commercialization and as the event is not yet approved in Europe, this represents a step forward against the “mirror policy” with the European Union. In an effort to move forward in finding a mechanism to recognize intellectual property rights, Monsanto (with support of the seed industry) developed a private agreement with farmers. Up until now, 3 640 farmers have signed the agreement, which represents 31.5 percent of the total area.