Dissertation > Excellent graduate degree dissertation topics show

Isolation, Identification and Characterization of a Novel Elastase from Chryseobacterium Indologenes

Author: ZhaoPeiPei
Tutor: WuZuo
School: Sichuan Agricultural University
Course: Biochemistry and Molecular Biology
Keywords: Chryseobacterium indologenes Elastase Purification Enzymatic properties Proteolytic characteristics
CLC: Q78
Type: Master's thesis
Year: 2012
Downloads: 25
Quote: 0
Read: Download Dissertation

Abstract


Elastase is a kind of protease that can specially degrade elastin. It has a promising application prospect in the food industry, medicine, daily chemical industry, environmental protection and biological control, which shows the high commercial value of elastase. In the study, a microbial strain with the high elastic proteolytic activity was identified from the cowhells powder plate with contamination bacteria. And the elastase produced by the strain was purified. Furthermore, its enzymatic properties and the hydrolysis characteristics on different proteins were studied. The main results are as follows:(1) A contamination bacterium named StrainWZE87was obtained from laboratory due to its strong hydrolysis ability for cowhells powder. Its original enzyme activity was high up to71.06U/mL. Seen from the morphological identification, the physio-biochemical characteristics, and the16S rDNA phylogenetic analysis, the StrainWZE87was identified as Chryseobacterium indologenes.(2) By using (NH4)2SO4fractional precipitatation, Q sepharose fast flow chromatography, Sephadex G-75chromatography, the elastase was purified from C. indologenes WZE87. SDS-PAGE showed that the molecular weight of the electrophoresis pure elastase was about26KDa. The resutls indicated the overall purification was8.3-fold, the recovery of activity was5.8%, and the specific activity was up to2376.5U/mg.(3) Enzymatic characterizations of the purified elastase were measured. The results revealed that its optimal temperature was37℃. After incubation at50℃for30min, it maintained85%of the relative activity, which meant the elastase showed a some degree of thermostability. However, the relative activity was sharply dropped or eventually lost when the elastase was treated above60℃for30min. The optimal pH of the elastase was pH8.0or pH7.5in boric acid buffer or in Tris-HCl buffer, respectively. After treated in the pH5.5-6.5or pH10-11buffers for24h, the elastase remained over60%of its relative activity. Then, the elastase activities were inhabited partly and left with67%to96%relative activity in5mmol/L Li+, Na+, Ca2+, K+, EDTA and0.01mmol/L mercaptoethanol. Furthermore, Mn2+and SDS resulted in a reduction of the elastase activities more than50%. Particularly, Zn2+, Fe2+and Fe3+showed the obvious inhibition effect on the elastase activities, and the residual activities decreased to7%,0%and0%, respectively. However, Mg2+showed a weak activation to enhance the elastase activity up to103%.(4) The elastase from C. indologenesWZE87was prior to degrade elastin in the mixture of elastin and other proteins due to its specific adsorption for elastin. The results found the elastase also possessed the strong hydrolysis abilities for elastin, casein, gelatin, and isolated soy protein.

Related Dissertations

  1. Studies on Isolation, Purification and Chemical Structure for Polysaccharides from Camellia Chrysantha(Hu) Tuyama,S567.19
  2. Study on the Preparation of the Low Molecular Weight Fuciodan from Sargassum Henslowianum (C.Agardh) and Anti-tumor Activity,TS254.9
  3. Optimization of Fermentation Conditions, Purification, Cloning and Expression of a Cold-active Lipase from Pseudomonas Sp.RT-1,TQ925
  4. Extraction, Purification and Antifungal Activity of Anthocyanins in Drop Fruits of Chinese Baberry,TQ914.1
  5. Purification of Human Respiratory Syncytial Virus Fusion Protein with Immunomagnetic Microsphere Technology,R373
  6. Identification of Marine Sreptomyces Sp. GY-4 and Researches on Its Antimicrobial Substances,Q936
  7. Prokaryotic Expression and Purification of Human Beta-Defensin-9,Q78
  8. Biochemical Characterization and Molecular Modification of a Novel Marine Mud-derived Pyrethroid Hydrolase,X172
  9. Screening of Bacterial Strains with High α-Galactosidase Activity and Its Gene Cloning, Expression, Purification and Characterization,TQ925
  10. Lipase-catalyzed Transesterification of Lard to Produce L-ascorbyl Fatty Acid Esters,TS221
  11. Study of Isolation and Identification on Antimicrobial Substances Produced by Lactobacillus Acidophilus NX2-6,TS201.3
  12. Study on Antioxidant Activities and Lipase-catalyzed Transesterification of Lard to Produce L-ascorbyl Fatty Acid Esters,TS202.3
  13. Study on Extraction,purification and Antioxidant Activity of Wheat Germ Polysaccharides,TS210.1
  14. Isolation, Purification and Antioxidant Activity of Proteins from Chinese Yam,TS255.1
  15. Extraction of the Lipase from Pseudomonas Cepacia S31 and Its Applications in Food,TS201.25
  16. Studies on Extracting Mitochondrial DNA and Gene Expressions in Brassica Napus L,S565.4
  17. The Research on the Antioxidant Fat-Solube Compositions of Salicornia Herbacea L.,R284.1
  18. Purification of Recombinant Schistosoma Japonicum Protein SjGST and Preparation and Characterization of the Monoclonal Antibody,R392
  19. Isolation and Identification of Antimicrobial Substance Produced by Bacillus Subtilis fmbJ,TQ920.6
  20. Cloning and Expression of Fimn Gene of Bordetella Bronchiseptica in Rabbitry and Establishment of Rapid Detection Method,S858.291
  21. The Treatment of Experimental Autoimmune Myasthenia Gravis Rats by Using 4-Mercaptoethylpyridine-based Absorbent,R746.1

CLC: > Biological Sciences > Molecular Biology > Genetic engineering (genetic engineering)
© 2012 www.DissertationTopic.Net  Mobile