Glucose inhibits the formation of gas vesicles in Haloferax volcanii transformants |
| |
Authors: | Hechler Torsten Frech Miriam Pfeifer Felicitas |
| |
Institution: | Institut für Mikrobiologie und Genetik, TU Darmstadt, D-64287 Darmstadt, Germany. |
| |
Abstract: | The effect of glucose on the formation of gas vesicles was investigated in Haloferax mediterranei and Hfx.volcanii transformants containing the mc- gvp gene cluster of Hfx. mediterranei (mc-vac transformants). Increasing amounts of glucose in the medium resulted in a successive decrease in the amount of gas vesicles in both species, with a complete inhibition of their formation at glucose concentrations of > 70 mM in mc-vac transformants, and 100 mM in Hfx. mediterranei . Maltose and sucrose imposed a similar inhibitory effect, whereas xylose, arabinose, lactose, pyruvate and 2-deoxy-glucose had no influence on the gas vesicle formation in mc-vac transformants. The activities of the two mc-vac promoters were strongly reduced in mc-vac transformants grown in the presence of > 50 mM glucose. The gas vesicle overproducing ΔD transformant (lacking the repressing protein GvpD) also showed a glucose-induced lack of gas vesicles, indicating that GvpD is not involved in the repression. The addition of glucose was useful to block gas vesicle formation at a certain stage during growth, and vice versa , gas vesicle synthesis could be induced when a glucose-grown culture was shifted to medium lacking glucose. Both procedures will enable the investigation of defined stages during gas vesicle formation. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|