 |
 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Isolation and Characterization of Extracellular Halophilic Ribonuclease from Halotolerant Pseudomonas species) ผู้เขียน: Werasit Kanlayakrit, Takahiro IKEDA, Somporn Tojai, ดร.มังกร โรจน์ประภากร, รองศาสตราจารย์ , ดร.สาโรจน์ ศิริศันสนียกุล, ศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractA halotolerant bacterium isolated from Thai fish sauce, obtained in Surathani province, was identified as a Pseudomonas sp. No. 3241. This strain showed halophilic ribonuclease activity. When casamino acids (CA) and yeast extract (YE) were used as the nitrogen source in a mini jar fermenter, a ratio concentration of CA to YE of 15:20 g/l in Sehgal and Gibbons Complex (SGC) medium, without NaCl, gave maximum growth and ribonuclease activity (18.18 U/ml). The ribonuclease enzyme was optimal at pH 10.0 and at the temperature of 50?C. It had marked halophilic enzyme properties that required an optimal NaCl concentration of 3 M. The ribonuclease was stable between pH 6.0 and 9.0 and at temperatures between 30 and 40?C. |
 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Extracellular Halophilic Ribonuclease from a Halotolerant Pseudomonas sp. : Purification and Characterization) ผู้เขียน: Werasit Kanlayakrit, อนันต์ บุญปาน, Takahiro IKEDA, Somporn Tojai สื่อสิ่งพิมพ์:pdf AbstractA halotolerant bacterium, Pseudomonas sp. No. 3241, isolated from Thai fish sauce obtained in Suratthani province, produced an extracellular ribonuclease when cultivated aerobically without NaCl in Sehgal and Gibbons complex medium (SGC medium). Ribonuclease was purified by ethanol precipitation, Sephadex G-150 gel filtration and DEAE Toyopearl 650M anion-exchange chromatography. The purity and molecular weight were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The result showed that the molecular weight of ribonuclease from halotolerant Pseudomonas sp. No. 3241 was 61,000 daltons. Purified ribonuclease was optimum at pH 10.0 and at temperature of 40?C. Purified ribonuclease was stable between pH 6.0 and 10.0 and at temperatures between 30 and 40?C. This enzyme had marked halophilic enzyme properties that required an optimum NaCl concentration of 3.0 M (18%). |
 |