Effects of adding amino acids on creatinase production using response surface method

• Main Authors: Jung-Ji Chen, 陳俊吉
• Other Authors: Shau-Wei Tsai
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/23673153048127182390

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 91 === The ceatinase was produced from the gene of Pseudomonas putida NTU-8 expressed by a recombinant Escherichia coli JM109. This expression system was constructed by using a pQE-51-pSCR01 vector fused with a chitinase signal peptide, with which the gene product can excrete to the periplasmic space . Cell growth enchancement was found by incubating the recombinant E. coli in Luria-Bertani medium when an inducer of isopropyl-β-D-thiogalactopyranoside (IPTG) was added at an appropriate time. Such behavior might be attributed to the activated usage of certain amino acids. Similar behaviors of increasing cellgrowth and creatinase activing were obtained when adding threonine 、arginine 、histidine and methionine in the R medium. Therefore a Response Surface Method (RSM) with Central Composite Design (CCD) where threonine 、arginine and methionine were as the designed valuables were employed to find the optimal condition for creatinase production. The results indicated that the higher of threonine concentration and the lower of methionine concentration were, the better was the producivity for creatinase