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פותח על ידי קלירמאש פתרונות בע"מ -
Defense mechanisms of conifers: Relationship of monoterpene cyclase activity to anatomical specialization and oleoresin monoterpene content
Year:
1991
Authors :
לוינסון, אפרים
;
.
Volume :
96
Co-Authors:
Lewinsohn, E., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Gijzen, M., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Savage, T.J., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Croteau, R., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Facilitators :
From page:
38
To page:
43
(
Total pages:
6
)
Abstract:
Cell-free extracts from Pinus ponderosa Lawson (ponderosa pine) and Pinus sylvestris L. (Scotch pine) wood exhibited high levels of monoterpene synthase (cyclase) activity, whereas bark extracts of these species contained no detectable activity, and they inhibited cyclase activity when added to extracts from wood, unless polyvinylpyrrolidone was included in the preparation. The molecular mass of the polyvinylpyrrolidone added was of little consequence; however, polyvinylpolypyrrolidone (a cross-linked insoluble form of the polymer) was ineffective in protecting enzyme activity. Based on these observations, methods were developed for the efficient extraction and assay of monoterpene cyclase activity from conifer stem (wood and bark) tissue. The level of monoterpene cyclase activity for a given conifer species was shown to correlate closely with the monoterpene content of the oleoresin and with the degree of anatomical complexity of the specialized resin-secreting structures. Cyclase activity and monoterpene content were lowest in the stems of species containing only isolated resin cells, such as western red cedar (Thuja plicata D. Don). Increasing levels of cyclase activity and oleoresin monoterpenes were observed in advancing from species with multicellular resin blisters (true firs [Abies]) to those with organized resin passages, such as western larch (Larix occidenta/is Nutt), Colorado blue spruce (Picea pungens Engelm.) and Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco). The highest levels of cyclase activity and oleoresin monoterpenes were noted in Pinus species that contain the most highly developed resin duct systems. The relationship between biosynthetic capacity, as measured by cyclase activity, monoterpene content, and the degree of organization of the secretory structures for a given species, may reflect the total number of specialized resin-producing cells per unit mass of stem tissue.
Note:
Related Files :
conifers
Defense mechanisms
forest trees
Monoterpene
oleoresin
trees
עוד תגיות
תוכן קשור
More details
DOI :
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
20972
Last updated date:
02/03/2022 17:27
Creation date:
16/04/2018 23:40
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Scientific Publication
Defense mechanisms of conifers: Relationship of monoterpene cyclase activity to anatomical specialization and oleoresin monoterpene content
96
Lewinsohn, E., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Gijzen, M., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Savage, T.J., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Croteau, R., Inst. Biol. Chem. and Biochemistry, Biophysics Program, Washington State University, Pullman, WA 99164-6340, United States
Defense mechanisms of conifers: Relationship of monoterpene cyclase activity to anatomical specialization and oleoresin monoterpene content
Cell-free extracts from Pinus ponderosa Lawson (ponderosa pine) and Pinus sylvestris L. (Scotch pine) wood exhibited high levels of monoterpene synthase (cyclase) activity, whereas bark extracts of these species contained no detectable activity, and they inhibited cyclase activity when added to extracts from wood, unless polyvinylpyrrolidone was included in the preparation. The molecular mass of the polyvinylpyrrolidone added was of little consequence; however, polyvinylpolypyrrolidone (a cross-linked insoluble form of the polymer) was ineffective in protecting enzyme activity. Based on these observations, methods were developed for the efficient extraction and assay of monoterpene cyclase activity from conifer stem (wood and bark) tissue. The level of monoterpene cyclase activity for a given conifer species was shown to correlate closely with the monoterpene content of the oleoresin and with the degree of anatomical complexity of the specialized resin-secreting structures. Cyclase activity and monoterpene content were lowest in the stems of species containing only isolated resin cells, such as western red cedar (Thuja plicata D. Don). Increasing levels of cyclase activity and oleoresin monoterpenes were observed in advancing from species with multicellular resin blisters (true firs [Abies]) to those with organized resin passages, such as western larch (Larix occidenta/is Nutt), Colorado blue spruce (Picea pungens Engelm.) and Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco). The highest levels of cyclase activity and oleoresin monoterpenes were noted in Pinus species that contain the most highly developed resin duct systems. The relationship between biosynthetic capacity, as measured by cyclase activity, monoterpene content, and the degree of organization of the secretory structures for a given species, may reflect the total number of specialized resin-producing cells per unit mass of stem tissue.
Scientific Publication
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