Regulation by overlapping promoters of the rate of synthesis and deposition into crystalline inclusions of Bacillus thuringiensis delta-endotoxins.

ABSTRACT: During sporulation, Bacillus thuringiensis produces intracellular, crystalline inclusions comprised of a mixture of protoxins active on insect larvae. A major class of these protoxin genes, designated cry1, is transcribed from two overlapping promoters (BtI and BtII) utilizing RNA polymerase containing sporulation sigma factors sigma(E) and sigma(K), respectively. Fusions of these promoters to lacZ were constructed in order to analyze transcription patterns. Mutations within the -10 region of the BtII promoter (within the spacer region of the BtI promoter) which departed from the consensus -10 sequence for either sigma(E) or sigma(K) resulted in inactivation of transcription from BtII and a fivefold stimulation of transcription from BtI. In contrast, transcription from both promoters was i

SUBMITTER: Sedlak M 

PROVIDER: S-EPMC94337 | biostudies-literature | 2000 Feb

REPOSITORIES: biostudies-literature