Current Biotechnology

Progress on Analytical Methods of Imaging Genomics
TAN Jun, YUAN Shaoxun, MING Wenlong, SUN Xiao*
2018, 8(4): 277-283. DOI: 10.19586/j.2095-2341.2018.0045
Abstract ( ) PDF (2980KB)( )

The association analysis between genotypes and phenotypes has become an emphasis of Precision Medicine in the context of biomedical big data, by which the correlation between disease-associated phenotypic characteristics, genetics polymorphism and gene activities can be revealed. Imaging genomics, a new burgeoning and interdisciplinary research field, can extract the image characteristic of gene polymorphism or gene expression by integrating and analyzing image data and genome data. Thus, diagnostic method based on image features is likely to be noninvasive and promising. The paper principally expounded the main methods in the field of imaging genomics including genome data analysis, image data analysis and genome-image data fusion. And clinic application of imaging genomics such as assistant diagnosis of diseases, predict of clinical outcome and evaluation of curative effect was also discussed in this paper. At last, the future development of imaging genomics was prospected.

Application of Isothermal Nucleic Acid Amplification Technique in Pathogen Detection
PENG Zhi1, CHEN Gangyi2, LIU Xuefei1, HUANG Xinhe1*
2018, 8(4): 284-292. DOI: 10.19586/j.2095-2341.2018.0011
Abstract ( ) PDF (3057KB)( )

In recent years, new infectious diseases, such as severe acute respiratory syndrome (SARS) and H7N9 avian influenza, have outbroken one after another, which seriously threatened human health and the sustainable development of society and economy, and brought severe challenges to the prevention and control of infectious diseases. Pathogen detection is an important link in the prevention and control of infectious diseases, and therefore more and more new techniques have been applied in it. As a rapid and high sensitivity pathogen detection technology, isothermal nucleic acid amplification technology has obtained the considerable development. The principle, important characteristics and application progress in pathogen detection of isothermal nucleic acid amplification technique were reviewed, which were expected to provide important references for the promotion and application of this valuable technique.

Progress on Genetic Transformation of Animals and Plants Based on Nano-gene Vector
WANG Anqi§, ZHU Huaxin§, ZHAO Xiang, CUI Jianxia, WANG Yan*, CUI Haixin*
2018, 8(4): 293-301. DOI: 10.19586/j.2095-2341.2018.0005
Abstract ( ) PDF (1144KB)( )

Transgenic technology plays an important role in the cultivation of excellent new varieties of animals and plants. With the development of nanobiotechnology, genetic transformation technology of animals and plants, which is based on gene vector constructed by nano-materials, is of great significance in developing novel transgenic methods for animals and plants, accelerating the largescale preparation of genetically modified germplasm materials and the process of cultivating new varieties. The types and properties of nano-gene vectors were reviewed. And in combination with the progress on genetics and breeding of animals and plants, the characteristics and advantages of nano-gene vectors compared with other vectors were analyzed. In the meantime, the basic principle and operation process of gene transfection technology based on nano-gene carrier, as well as its application in genetic transformation of animals and plants were expounded emphatically, which was expected to provide a new thought for genetic engineering transformation of animals and plants.

Effects of Molecular Hydrogen on Cervical Cancer Cells
SHANG Lei, LI Jiala, SU Zehua, XIE Fei, MA Xuemei*
2018, 8(4): 302-310. DOI: 10.19586/j.2095-2341.2017.0057
Abstract ( ) PDF (6600KB)( )

The effects of molecular hydrogen on various diseases are predictable. It is easy to use without side effects. Many results also prove that molecular hydrogen is effective on the prevention and treatment of tumors. The effects of molecular hydrogen on HeLa cells were determined in terms of cell proliferation, cell neoplasm formation, viability, cell cycle, apoptosis, migration and invasion. The results showed that hydrogen treatment led to a marked reduction of sphere number and average diameter in HeLa cells. And hydrogen treatment induced markedly fewer and smaller colonies in HeLa cells. Hydrogen treatment induced in a slightly slower growth rate in HeLa cells. And it had a certain role in promoting the expression of vimentin in HeLa cells. In addition, the effect of molecular hydrogen on HeLa cell cycle was significant. In parallel, a matrigel invasion assay was also performed to determine the effect of hydrogen treatment on the invasion of HeLa cells. Wounding assay was employed to examine the influence of hydrogen treatment on the migration of human ovarian cancer cells. The presence of hydrogen significantly inhibited the motile nature of HeLa cells. The results showed that molecular hydrogen promoted the expression of vimentin and decreased the proliferation rate of cells, but inhibited the invasion and migration of HeLa cells. It provides a certain experimental basis for the prevention and treatment of cervical cancer.

The Effects of Chitosan-mediated Spheroid Formation on the Migration and Chemotaxis of Umbilical Cord Mesenchymal Stem Cells
LI Huajie, XU Xiongfeng, QIU Bo*
2018, 8(4): 311-316. DOI: 10.19586/j.2095-2341.2018.0040
Abstract ( ) PDF (6080KB)( )

To investigate the effects of chitosan-mediated spheroid formation on the migration and chemotaxis of mesenchymal stem cells (MSCs). The original MSCs were extracted from umbilical cord tissue, and were cultured on chitosan(CS) membranes, compared with these on trational adherent substrate. MSCs of two groups were collected after 72 hours. Migration rate and chemotactic effect of MSCs were measured by wound healing assay and tranthwell migration assay, observed and screened the cell morphology. The expression levels of genes related to MSCs migration and chemotaxis in two cultures were further detected by real-time PCR（RT-PCR). The results showed that, compared with the MSCs derived on adherent substrate, there was a significant statistical difference (P<0.01) that MSC spheroids derived on CS have more active migration and chemotaxis in vitro. And the expression level of migration genes, such as CXCR4, CXCR7, MCP-1, MMP-1, MMP-2, MMP-9 and TIMP-2, was significantly up-regulated in the MSC spheroids derived on CS (P<0.01). The experimental results showed that chitosan-mediated spheroid formation could enhanced the activities of migration and chemotaxis of MSCs.

QTL Mapping for Gray Leaf Spot Resistance in Maize Based on Bulk Sequencing
CUI Fengchao, WANG Pingxi, LIU Xiaogang, ZOU Cheng*
2018, 8(4): 317-323. DOI: 10.19586/j.2095-2341.2018.0015
Abstract ( ) PDF (2448KB)( )

Gray leaf spot (GLS) caused by Cercospora zeine and Cercospora zeae-maydis is one of the crucial fungal foliar diseases throughout the world. In this study, we constructed one population of BC1F1 with GLS-resistance inbred line Suwan1 and GLS-susceptible inbred line HM01, which was regarded as recurrent parent. After evaluation of GLS resistance for the BC1F1 population in natural condition, one resistant and one susceptible DNA bulks were prepared, both of which included 30 extreme individuals. With the help of high-throughput sequencing technology, quality control and data analysis were utilized to detect genomic variant information in the two bulks. As a result, totally 29 resistant quantitative trait loci (QTL) containing 2 768 genes according to MaizeGDB website were identified via the statistical test of sequencing depth differences of the two bulks. In addition, 2 768 genes were projected onto Oryza sativa and Arabidopsis thaliana genome on the Phytozome website. Finally, three genes located at chromosome 1, 5 and 10 were selected as candidate genes of GLS resistance.

Study on Extraction Process, Antioxidant Activity and Application in Hair Dyeing of Purple Pigment from Wheat
YANG Sanwei1§, ZHAO Jiajia1§, QIAO Ling1, ZHENG Xingwei1, LU Yanzhen2, LI Liujun2, ZHANG Jiancheng1*
2018, 8(4): 324-329. DOI: 10.19586/j.2095-2341.2017.0162
Abstract ( ) PDF (1357KB)( )

With purple wheat bran as raw material, natural purple pigment was extracted by alkali water cracking, macroporous adsorption resin purifying, sodium filter membrane concentrating and evaporation concentrating. The extraction conditions were optimized through single factor experiments. And at room temperature (25~30℃), the optimum process conditions for extracting purple pigment were determined as follows: Extraction time was 60 min, the ratio of material to liquid was 1∶4 (g/mL), 3 times of extraction. Antioxidant experiments showed that the extracted wheat purple pigment had high antioxidant activity. Moreover, the wheat purple pigment could dye wool into different colors after reacting with different metal ions. The results showed that the wheat purple pigment extracted by optimized processes had high purity and strong antioxidant activity, and it had great development potential and practical value.

Effects of Oil Contents of Peanut Cakes on Tofu Quality
GUO Yalong, HU Hui, WANG Qiang*, LIU Hongzhi*
2018, 8(4): 330-337. DOI: 10.19586/j.2095-2341.2018.0029
Abstract ( ) PDF (1322KB)( )

In order to determine the suitable oil content of raw material for peanut tofu preparation, peanut tofu was produced by the method combining transglutaminase (TG) and high-temperature pressure cooking (HTPC), using low-temperature peanut cakes (LTPC) as the raw material. The effects of different oil contents （6.89%, 10.12%, 15.43%, 20.28% and 25.54%） of peanut cakes on the tofu texture were studied, the color and cooking loss of the peanut tofu were compared with the commercial soybean tofu, and the structural changes of peanut proteins during tofu processing were also analyzed. The results showed that the tofu texture was significantly influenced by the oil content of the LTPC（P<0.05）, and the peanut tofu could be made from the LTPC with oil contents from 6.89% to 20.28%. When the oil content of the LTPC was 6.89%, the texture and cooking loss of the obtained peanut tofu were close to those of the commercial soybean gypsum tofu, and its degree of yellow value b (8.38) was significantly lower than that of the soybean gypsum (15.86) and bitter (16.56) tofu (P<0.05), which might be more accepted by the consumers. Besides, the analysis on the structural changes of peanut proteins showed that TG had good effect on peanut proteins, when the oil contents of LTPC were low (6.89%~20.28%), then the peanut proteins could be completely denatured after subsequent HTPC treatment, and finally hydrophobic interaction and disulfide bonds were formed to stabilize the gel structure of peanut tofu. This study provided technical guidance and theoretical support for peanut tofu processing.

Optimization of SRAP-PCR System and Primers Screening for Southern Chinese Herbs Alpinia oxyphylla Miquel
OU Hongya, HAN Dongmiao, HUANG Zibao, ZHANG Mingkang, ZHOU Congcong, GAO Bingmiao*
2018, 8(4): 338-344. DOI: 10.19586/j.2095-2341.2017.0147
Abstract ( ) PDF (3710KB)( )

In order to establish the optimal SRAP-PCR system for southern Chinese herbs Alpinia oxyphylla Miquel and screen the specific primers for studying the genetic diversity of Alpinia oxyphylla Miquel in different geographical groups, the different geographical groups of Alpinia oxyphylla resources in Hainan were collected, and the genomic DNA of Alpinia oxyphylla Miquel was extracted by plant genome DNA extraction kit and then the purity and concentration of the DNA samples were detected. The optimal reaction system (total volume of 25 μL) was obtained by orthogonal test: Taq DNA polymerase 0.5 U, dNTPs 4 mmol/L, Mg2+ 2 mmol/L, primers each 2 μmol/L, DNA templates 10 ng, 10×PCR buffer 2.5 μL. 7 pairs of specific primers were screened by the optimal reaction system from 144 primers, and the sizes of their amplified fragments were within 100~2 000 bp and evenly distributed. And the ratios of polymorphic bands were above 85%. The results of this study laid a foundation for the study on genetic diversity of southern Chinese herbs Alpinia oxyphylla Miquel.

Screening and Identification of a Condensed Tannin Degrading Bacteria and its Degradation Effect
CHEN Duyu, WANG Sen, ZHANG Yu, XU Lei*
2018, 8(4): 345-350. DOI: 10.19586/j.20952341.2018.0023
Abstract ( ) PDF (1399KB)( )

The purpose of this study was to screen and isolate a condensed-tannin degrading bacteria, then identify the strain, and explore its degrading ability. In this study, from cattle and sheep feces, a strain of degrading bacteria which could utilize condensed tannin as a sole carbon source was obtained by gradient acclimation method. Through morphological characteristics observation, Biolog physiological, biochemical tests and 16S rRNA gene sequence analysis, strain B1 was identified as a gram-negative bacterium, which is belonging to the genus Enterobacter sp. and clustered with Enterobacter xiangfangensis 10-17T in a phylogenetic tree constructed. Comprehensive determination was detected by ultraviolet spectrophotometry and high performance liquid chromatography, the maximum OD600 value of B1 cultured for 24 hours was reached to 2.5. The degradation rate of larvae tannin by bacteria B1 was analyzed by the calculated changes in procyanidins and catechins, results showed that the degradation rate reached more than 90% at 72 hours and there was catechin generated. In addition, when explored the effects of additional nitrogen and carbon sources, the results showed that the addition of nitrogen source could slightly increase the degradation ability of bacterium B1, but the addition of carbon source would reduce the degradation rate. The results enriched the overall study of condensed tannins, enhanced the application value of condensed tannins, and further explored the mechanism of microbial degradation of condensed tannins.

Optimization of Ultrasonic Assisted Enzymatic Extraction of Polysaccharide from Kadsura longipedunculata by Response Surface Analysis
HU Qinhan, WANG Wei, LUO Yingbiao, DU Fang, YANG Liuqing, ZHAO Ting*
2018, 8(4): 351-357. DOI: 10.19586/j.2095-2341.2018.0033
Abstract ( ) PDF (4992KB)( )

In this study, the ultrasonic-assisted enzymatic extraction was employed to extract polysaccharides from Kadsura longipedunculata and the extraction process was also studied. Based on single factor experiments, the response surface methodology (RSM) was carried out to further optimize extraction conditions. The optimal extraction condition were extraction temperature 57℃, extraction time 66 min, extraction pH 4.8, enzyme dosage 3.0%. Under the optimum conditions, the yield of crude polysaccharide was 8.73%±0.25%. In summary, the extraction process involved in the study could significantly reduce polysaccharide extraction time and solvent consumption, reduce temperature and effectively improve the extraction yield. Therefore, this process can be applied in the extraction of polysaccharides from Kadsura longipedunculata. The results provided a scientific basis for developing and utilization of polysaccharide from Kadsura longipedunculata.

Study on Detection of Protein Sumoylation by UFDS System
GONG Yu1,2, LI Yingqiu2
2018, 8(4): 358-365. DOI: 10.19586/j.2095-2341.2017.0166
Abstract ( ) PDF (7164KB)( )

To verify Ubc9 fusion-directed sumoylation (UFDS) system as a method for protein detection of sumoylation, the Ubc9-PKCθ fusion expression vector was constructed and cotransfected into 293T cells with SUMO1 expression vector. Then the sumoylation of Ubc9-PKCθ was tested by coimmunoprecipitation and Western blot. Results showed that, Ubc9-PKCθ could be modified by SUMO in UFDS system. SENP1 could induce desumoylation of Ubc9-PKCθ. Compared to wild type Ubc9-PKCθ, the sumoylation of multi-points KR mutants of Ubc9-PKCθ was significantly weakened. And compared with wild type PKCθ, the sumoylation of multi-points KR mutants of PKCθ was totally undetectable. Results indicated that UFDS system is useful for detecting protein sumoylation, but has a certain defect in identifying potential sumoylation sites.

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