[Phenotypic expression of a 100-pair nucleotide deletion in the regulatory region of the Bacillus subtilis riboflavin operon].

: Assessment of specific activity of riboflavin synthase and the level of riboflavin accumulation in strains with a 110-nucleotide deletion in the regulatory region of the riboflavin operon showed that this deletion specified semi-constitutive expression of the operon. This was assumed to be connected with the elimination of three nucleotides from a potential transcription antiterminator.