The time required for cro gene product to establish dominance in coliphage lambda lysogens.
To measure the length of heating required to convert a lambda lysogen in the immune (im+) phase into the anti-immune (im-) phase, rex gene activity was used as an indicator. It was observed that 5 min heating at 41 degrees C did not shift any lysogenic cells of 594 (lambda N-c1857O-) from the im+ phase into the im- phase, and it took 17 min heating at 41 degrees C followed by long hours of culture at 30 degrees C to shift half of the lysogenic cells into the im- phase. Such a length of heating is too long to be accounted for by blocking of the expression of lambda repressor by cro gene product. The result is more consistent with accumulation of a certain level of cro gene product during heating so that the synthesis of the repressor is blocked even after a return to low temperature.
D010582:Bacteriophage lambda / Q000235:genetics* / Q000502:physiology; D004268:DNA-Binding Proteins; D005786:Gene Expression Regulation; D005814:Genes, Viral; D006358:Hot Temperature; D007700:Kinetics; D008242:Lysogeny; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000502:physiology*; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins
D004268:DNA-Binding Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins; C016649:phage repressor proteins