title: Alterations in the activity and structure of pectin methylesterase treated by high pressure carbon dioxide.
abstract: The influence of high pressure carbon dioxide (HPCD) on the activity and structure of pectin methylesterase (PME) from orange was investigated. The pressures were 8-30 MPa, temperature 55 degrees C and time 10 min. HPCD caused significant inactivation on PME, the lowest residual activity was about 9.3% at 30 MPa. The SDS-PAGE electrophoretic behavior of HPCD-treated PME was not altered, while changes in the secondary and tertiary structures were found. The beta-structure fraction in the secondary structure decreased and the fluorescence intensity increased as HPCD pressures were elevated. After 7-day storage at 4 degrees C, no alteration of its activity and no reversion of its beta-structure fraction were observed, while its fluorescence intensity further decreased.
authors.affiliation: College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture, Engineering Research Center for Fruit & Vegetable Processing, Ministry of Education, Beijing 100083, China.
authors.forename: Linyan
authors.initials: L
authors.lastname: Zhou
authors.forename: Jihong
authors.initials: J
authors.lastname: Wu
authors.forename: Xiaosong
authors.initials: X
authors.lastname: Hu
authors.forename: Xian
authors.initials: X
authors.lastname: Zhi
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Liao
mesh_terms: D002245:Carbon Dioxide / Q000494:pharmacology*; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry*; D032084:Citrus sinensis / Q000201:enzymology*; D004795:Enzyme Stability; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry*; D011312:Pressure
chemical_list: D010940:Plant Proteins; D002245:Carbon Dioxide; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase