STP2201 A CHROMOSOMAL PROMOTER SEQUENCE OF STREPTOCOCCUS-THERMOPHILUS

Analysis of the structural and functional properties of chromosomal DN A fragments of Streptococcus thermophilus ST128 delineated the promote r sequence STP2301 and identified its -35, -10 and Shine-Dalgarno regi ons. STP2201 was used in cloning vectors derived from small resident p lasmids pER8 (2094 bp) and pER371 (2672 bp) of S. thermophilus strains to facilitate expression of a Streptomyces sp, marker gene (cholester ol oxidase) in lactic acid bacteria, Cell extracts of ST128 transforma nts converted up to 75% of cholesterol into 4-cholesten-3-one during a h of incubation.