Regulation of $\beta$-galactosidase Biosynt hesis in Lactobacillus sporogenes

Lactobacillus sporogenes에서$\beta$-galactosidase 생합성 조절

  • 이정희 (고려대학교 농과대학 유전공학과) ;
  • 최용진 (고려대학교 농과대학 유전공학과)
  • Published : 1990.12.01

Abstract

Regulation of $\beta$ -galactosidase formation was studied with Lactobacillus sporogenes. Synthesis of the enzyme was effectively induced by isopropyl- $\beta$-D-thiogalactopyranoside (IPTG) or galactose, and to a much lower level by lactose. When 15 mM glucose was added at the different intervals to the cultures that had been in contact with IPTG, the same levels of inhibition of the enzyme synthesis were observed (approximately one-third the differential rate of a control culture without glucose). This suggests that glucose did not interfere with the entry of the inducer into the cells, but interfere with the formation of $\beta$ -galactosidase through catabolite repression. The glucose inhibitory effect was not overcome by adding CAMP or cGMP to the culture media.

Keywords

Regulation;$\beta$-galactosidase synthesis;Lactobacillus sporogenes;catabolite repression