| Автор | Osswald, Wolfgang F. |
| Автор | Shapiro, Jeffrey P. |
| Автор | Doostdar, Hamed |
| Автор | McDonald, Roy E. |
| Автор | Niedz, Randall P. |
| Автор | Nairn, C. Joseph |
| Автор | Hearn, C. Jack |
| Автор | Mayer, Richard T. |
| Дата выпуска | 1994 |
| dc.description | Acidic chitinases (EC 3.2.1.14) were isolated and characterized from 4-week-old nonembryogenic Citrus sinensis L. Osbeck cv ‘Valencia’ callus tissue. The enzymes were purified using size exclusion, anion exchange, and chromatofocusing HPLC techniques. Eleven isoforms were isolated with M<sub>1</sub>s between 26,000 and 37,400. Eight of the isoforms were purified to homogeneity, and all but one cross-reacted with a polyclonal antibody raised against a basic class I potato leaf chitinase. The isoelectric points (determined by chromatofocusing) were from pH 4.5 to 5.4. All hydrolases degraded chitin and four were capable of hydrolyzing solubilized shrimp shell chitosan suggesting they may be chitosanases (EC 3.2.1.99). Apparent chitosanase activity generally decreased with decreasing acetylation of the chitosan (i.e. from 20% to 0% acetylation). The chitinases and chitinases/chitosanases are predominantly endochitinases. Chitosanase activity was optimal at pH 5 while the pH optimum for chitinase activity ranged between pH 3.5 and 5.5. The chitinases and chitinases/chitosanases wer stable up to 60°C and showed their highest enzyme activity at that temperature. N-terminal sequences were obtained on three of the isoforms. One of the isoforms was identified as a class II chitinase and the other two as class III chitinases. |
| Формат | application.pdf |
| Издатель | Oxford University Press |
| Копирайт | © 1994 The Japanese Society of Plant Physiologists (JSPP) |
| Тема | Citrus |
| Тема | Defensive proteins |
| Тема | Hydrolases |
| Тема | Lysozyme |
| Тема | Plant tissue culture |
| Тема | Pathogenesis-related proteins |
| Тема | Regular Papers |
| Название | Identification and Characterization of Acidic Hydrolases with Chitinase and Chitosanase Activities from Sweet Orange Callus Tissue<sup>1</sup> |
| Тип | research-article |
| Electronic ISSN | 1471-9053 |
| Print ISSN | 0032-0781 |
| Журнал | Plant and Cell Physiology |
| Том | 35 |
| Первая страница | 811 |
| Последняя страница | 820 |
| Аффилиация | U.S. Horticultural Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture2120 Camden Road, Orlando, Florida 32803-1419, U.S.A. |
| Выпуск | 5 |
