Isolated population of plant single cells and method of preparing the same
This invention is a method of minimizing the variation of cell growth and production through homogeneous cell line development. To be more specific, it is the method of isolating and proliferating single cell clone from the procambium to promote the stability of the plant-derived biologically active substances production by solving the problems of decrease in cell growth and the productivity during the long term culture.
1. An isolated population of cells from a plant,
wherein the cells of the isolated population are characterized in that they (i) are derived from procambium of the plant, (ii) are innately undifferentiated, (iii) are homogeneous, and (iv) comprise the following characteristics:
(a) including a greater number of single cells or including smaller-sized cell aggregates in suspension culture than cells derived from dedifferentiated callus of the plant;
(b) having multiple vacuoles morphologically;
(c) being capable of growing faster and longer than cells derived from dedifferentiated callus of the plant; and
(d) having lower sensitivity to shear stress in a bioreactor than cells derived from dedifferentiated callus of the plant.
2. The isolated population of cells according to claim 1 , wherein the plant is the genus Taxus.
3. The isolated population of cells according to claim 2 , wherein the cells are capable of releasing paclitaxel 404-1077 times more than cells derived from dedifferentiated callus of the plant.
4. A method for producing a biologically active substance or substances, the method comprising the steps of:
(a) producing the active substance or substances by culturing in a medium the isolated population of cells of claim 1 ; and
(b) collecting said active substance or substances.
5. The method according to claim 4 , wherein in the step (a), a predetermined amount of the medium that has been used to culture the cells is removed and a predetermined amount of a new medium is introduced.
6. The method according to claim 4 , wherein the plant is the genus Taxus and the active substance is paclitaxel.
7. The method according to claim 6 , wherein the medium includes at least one component selected from the group consisting of methyl jasmonate, phenylalanine, and chitosan.
8. A method for preserving a plant cell line, the method comprising cryopreserving the isolated population of cells of claim 1 .