Concept explainers
To review:
The signal transduction pathway of Escherichia coli in response to a hypertonic solution, with the help of a diagram.
Given:
The labeled P-EnvZ was incubated with OmpR protein and the samples were tested for the presence of fluorescence at different time intervals. The results were recorded in Table 1 below:
Table 1: Labeled proteins observed at different intervals after the incubation of 32P-EnvZ with OmpR.
Duration after mixing 32P-EnvZ and OmpR (min) | ||||
0 | 2 | 5 | 10 | |
Presence of 32P label in EnvZ | High | Medium | Low | Absent |
Presence of 32P label in OmpR | Absent | Low | Medium | High |
Introduction:
Cells activate different genes under a specific situation. The bacterial cells like E. coli synthesize high OmpC protein levels in hypertonic solutions, as compared to hypotonic or isotonic solutions. Proteins, like EnvZ which is a membrane protein, get phosphorylated and also function as a protein kinase. EnvZ also phosphorylates proteins, like OmpR, which is a cytoplasm protein.
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Life: The Science of Biology
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