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Journal of Animal Science and Biotechnology 2018年第2期9卷 467-479页

作者： Dafei Yin Xiaonan Yin Xingyu Wang Zhao Lei Maofei Wang Yuming Guo Samuel E.Aggrey Wei Nie Jianmin Yuan State key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijingChina NutriGenomics Laboratory Department of Poultry ScienceUniversity of GeorgiaAthensGAUSA

Background: The effect of amylases combined with exogenous carbohydrase and protease in a newly harvested corn diet on starch digestibility, intestine health and cecal microbiota was investigated in broiler ***: Two hunderd and eighty-eight 5-day-old female chickens were randomly divided into six treatments: a newly harvested corn-soybean meal diet(control); control supplemented with 1,500 U/g α-amylase(Enzyme A);Enzyme A + 300 U/g amylopectase + 20,000 U/g glucoamylase(Enzyme B); Enzyme B + protease 10,000 U/g(Enzyme C); Enzyme C + xylanase 15,000 U/g(Enzyme D); and Enzyme D + cellulase 200 U/g + pectinase 1,000 U/g(Enzyme E). Growth performance, starch digestibility, digestive organ morphology, and intestinal microbiota were evaluated in the birds at 16 and 23 d of ***: Compared with the control diet, supplementation with Enzyme A significantly decreased ileum lesion scoring at 16 d of age(P glucoamylase or protease showed a beneficial effect on starch digestibility and intestinal microbiota diversity, and increased growth of broilers fed with newly harvested corn.

关键词： Amylase Broiler glucoamylase Microbiota diversity Newly harvested corn Protease

Expression and secretion of Aspergillus niger glucoamylase in Saccharomyces cerevisiae

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Science China Chemistry 1995年第2期38卷 195-201页

作者：李文清何鸣罗进贤 Biotechnology Research Centre Zhongshan University Guagnzhou 510275 China

Aspergillus niger glucoamylase GA 1 cDNA was inserted in between the yeast PGK promoter and terminator on plasmid pMA91. The resultant plasmid pMAG69 was introduced into Saccharomyces cerevisiae GRF18 by protoplast transformation. The A niger GA I cDNA was expressed efficiently under the contiol of PGK promoter and 99% of the gene products were secreted into the culture medium using its own signal sequence The recombmant yeast can digest 87% of starch in 2 d in the medium containing 10% starch. The recombinant plasmid pMAG69 can exist stably in 5. cerevisiae.

关键词： Aspergillus idger glucoamylase gene expression Sacehammyces cerevisiae plasmid stability.

Expression and secretion of barley α-amylase and *** glucoamylase in Saccharomyces cerevisiae

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Science China(Life Sciences) 1998年第2期41卷 113-118页

作者：罗进贤李政海李文清 1. Department of Biochemistry and Biotech-Research Center Zhongshan University 510275 Guangzhou China

cDNAs of barley α amylase and *** glucoamylase were cloned in one *** yeast shuttle plasmid resulting in the construction of expression secretion vector pMAG15. pMAG15 was transformed into *** GRF18 by protoplast transformation. The barley α amylase and *** glucoamylase were efficiently expressed under the control of promoter and terminator of yeast PGK gene and their own signal sequence. Over 99% of the enzyme activity expressed was secreted to the medium. The recombinant yeast strain, *** GRF18(pMAG15), hydrolyzes 99% of the starch in YPS medium containing 15% starch in 47 h. The glucose produced can be used for the production of ethanol.

关键词： barley α amylase and A.niger glucoamylase Saccharomyces cerevisiae expression and secretion.

Study on the molecular basis of glucoamylase overproduction of a mutant strain Aspergillus niger T21

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Science China(Life Sciences) 2001年第3期44卷 287-293页

作者：范晓春仇润祥刘丽唐国敏 1. Institute of Microbiology Chinese Academy of Sciences 100080 Beijing China

The molecular basis for increasing of the glucoamylase (GLA) production of an Aspergillus niger mutant T21 was investigated . Northern blot analysis showed that the amount of glaA specific mRNA of A . niger T21 was about 20 times higher than that of its start strain A . niger AS 3.795. The two glaA promoter fusions (PglaA)-uidAs were respectively introduced into A . niger. Analysis of GUS activity of the transformants revealed that the PglaA activity of the strain T21 is about 3 times stronger than that of the strain AS 3.795. It is considered to be one of the reasons for the increase of glaA transcriptional level in the strain T21. However, comparing with the 20 times increase in the amount of glaA mRNA the alteration of trans regulation should be the most important reason for that. The results of deletion analysis of 5′-cis region of A . niger T21 glaA gene indicated that the region from - 408 to - 513 bp upstream of ATG is responsible for the high level expression of glaA.

关键词： Aspergillus niger glucoamylase promoter activity comparison deletion analysis.

Immobilization of glucoamylase onto Novel Porous Supports Containing Cyclic Carbonate

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Chinese Chemical Letters 2001年第11期12卷 993-996页

作者： Huang, JX Huo, YL Li, Y Yuan, Z Nankai Univ Dept Chem State Key Lab Funct Polymer Mat Adsorpt & Separat Tianjin 300071 Peoples R China

glucoamylase was immobilized onto novel porous polymer supports containing cyclic carbonate. The relationship between activity of immobilized glucoamylase and the properties of porous polymer supports was investigated... 详细信息

关键词： glucoamylase immobilization polymer supports cyclic carbonate

Preparation of glucosamine by hydrolysis of chitosan with commercial α-amylase and glucoamylase

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第11期12卷 931-934页

作者： Sai-kun PAN Sheng-jun WU Jin-moon KIM Jiangsu Key Laboratory of Marine Biotechnology Huaihai Institute of Technology Lianyungang 222005 China School of Marine Science and Technology Huaihai Institute of Technology Lianyungang 222005 China Food Safety and Inspection Service Office of Field Operations US Department of Agriculture Albany iVY 12203 USA

Objective： In order to overcome the defects of chemical hydrolysis approach to prepare glucosamine, an enzymatic hydrolysis method was developed. Methods： Glucosamine was prepared by hydrolyzing chitosan, em- ploying e-amylase initially, and subsequently, glucoamylase. Results： The optimal hydrolyzing conditions were as follows： reaction time, 4 h; pH, 5.0; temperature, 50 ℃; and, α-amylase, 80 U/g for the initial reaction. Subsequently, glucoamylase was added in the presence of a-amylase. The optimal reaction conditions were found to be： reaction time, 8 h; pH, 4.5; temperature, 55 ℃; and, glucoamylase, 4000 U/g. The hydrolysates were subject to filtrating, concentrating to about 20% （w/w）, precipitating with five volumes of ethanol, and drying at 60 ℃ for 2 h. The content and the yield of glucosamine in the dried precipitate were 91.3% （w/w） and 86.2% （w/w）, respectively. Conclusions： The method developed in this study is a promising option in the preparation of glucosamine.

关键词： Glucosamine o-Amylase glucoamylase Hydrolysis

Hydrolysis of Raw Corn Starch Granules by glucoamylase and Product Inhibition During the Hydrolysis

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Transactions of Tianjin University 2005年第3期11卷 199-203页

作者：王金鹏曾爱武刘振袁希钢吴少敏 State Key Laboratory of Chemical Engineering School of Chemical Engineering Tianjin University Tianjin 300072 China

Raw corn starch granules were hydrolysized by glucoamylase in a chemostat. The hydro- lysis of three different-sized granules shows that smaller granules undergo more hydrolyzation than larger ones. After 78 h, 9700 of the granules was hydrolysized with diameter between 0.15 mm and 0.3 mm at 50 ℃. When corn starch concentration increased from 100 g/L to 250 g/L, the amount of reducing sugar produced was proportional to the initial substrate concentration and no substrate inhibition phenomenon appeared. In order to study the product inhibition exactly, the product from hydrolysis reaction itself was added into the hydrolysis system at the beginning of starch hydrolysis. Product inhibition with different quantities of product added were studied in the initial several hours, during which period enzyme inactivation could be neglected and product inhibition could be studied separately. The experiments indicate that product inhibition happens when the additional quantity exceeds 9.56 g/L.

关键词： hydrolysis starch granules glucoamylase product inhibition

Cloning of the Aspergillus awamori glucoamylase gene and expression in Saccharomyces cerevisiae

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Chinese Science Bulletin 1998年第10期43卷 855-859页

作者： Yongji Wang Hongdi Liu Tong Sun Shuzheng Zhang Chinese Acad Sci Inst Microbiol Beijing 100080 Peoples R China

The A. awamori glucoamylase I gene was obtained by RT_PCR and inserted into the plasmid pAC1. We constructed an expression vector pAC1_GA, which was used to transform the yeast S. cerevisiae AS 2 1364 without auxotrophic marker. The transformant secreted glucoamylase into the medium efficiently and degraded starch. The glucoamylase activity of the culture filtrate is up to 8 4 U/mL.

关键词： Aspergillus awamori glucoamylase gene cloning and expression Saccharomyces cerevisiae.

Sweet Potato Starch as a Carbon Source for Growth and glucoamylase Production from <i>Aspergillus niger</i>

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Advances in Microbiology 2014年第12期4卷 788-795页

作者： Alfred O. Ubalua Tissue Culture Unit Biotechnology Research and Development Center National Root Crops Research Institute (NRCRI) Umuahia Nigeria

A mesophilic strain of Aspergillus niger isolated from cassava effluent samples produced extracellular glucoamylase in submerged culture containing 2% (w/v) soluble or sweet potato starch. On soluble starch medium the maximum glucoamylase activity in the culture filtrate was 9.40 U/mg compared to 8.24 U/mg on sweet potato starch culture filtrate. The mycelial dry weight for both media was 494 and 418 mg respectively. The maximum glucoamylase activity was obtained at a growth temperature of 40°C and pH 4.5. The implication is that the bioprocess of utilizing sweet potato starch in the culture is attractive due to its relatively cheaper availability in Nigeria, making it even more favorable when economics is considered.

关键词： Aspergillus niger Sweet Potato Starch Submerged Fermentation Amylolytic Activity glucoamylase Prodcution

Fusion Expression of glucoamylase and Xylanase in Pichia pastoris

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Agricultural Biotechnology 2012年第5期1卷 48-51页

作者： Zhi WANG Baoqing DUN Jingang GU Xuan ZHAO Gu TIAN Ming LU Guiying LI National Key Facility for Crop Gene Resources and Genetic Improvement of Institute of Crop Sciences Chinese Academy of Agricultural Sciences Agricultural Culture Collection of China Institute of Agricultural Resources and Agricultural DivisionsChinese Academy of Agricultural Sciences College of Life Sciences Northeast Agricultural University

Employing RT-PCR amplification method, the mature pepfide coding sequence of glucoamylase （amyA） gene was amplified from total RNA of Talaro- myces emersonii and the xylanase （xyrut） gene from genomic DNA ofPaenibacillus sp. H10-3. The result showed that the mature peptide sequence of amyA is 1857 bp long and encodes 618 amino acids; and the mature peptide sequence of xynA is 636 bp long and encodes 211 amino acids. Then these two genes were spliced by overlap extension PCR （ SOE-PCR）, yielding fusion gene amyA-l-xynA. The fusion gene amyA-l-xynA was then cloned into a Pichia pastoris expression vector pPIC9 to produce the recombinant expression plasmid pPIC9-amyA-l-xynA. The recombinant plasmid pPICg-amyA-l-xynA was linearized and transformed into Pichia pastoris GSll5 via electric shock, yielding engineering strain ALX2. The maximum yields of glucoamylase and xylanase in ALX2 fermentation supernatant were determined as 10.7 and 51.8 U/ml, respectively.

关键词： glucoamylase Xylanase Fusion expression Pichia pastoris