5-BROMO-4-CHLORO-3-INDOLYL-β-D

异丙基-1-硫代β-D吡喃（型）半乳糖 isop-ropyl-1-thio-β-D-galactopyranoside

　　异丙基 -1-硫代β -D吡喃（型）半乳糖 isop-ropyl-1-thio-β -D-galactopyranoside 为 isopropyl-1-thio-β -D-galactopyranoside的缩写。是诱导大肠杆菌乳糖操纵子酶合成的强力诱导物。在培养基中加入该物 10-4 克分子时，即可通过存在于大肠杆菌细胞膜中的微量半乳糖苷渗透酶而被参入至细菌体内。通常诱导物质即根据这种通过操纵子的作用制造的β -半乳糖糖苷酶而被利用于代谢的。但 IPTG等不能

邻硝基苯-β-吡喃半乳糖苷 O－nitrophenyl－β－D－galactopyranoside

  　 　缩写为 ONPG。是广泛利用于β -半乳糖苷酶活力测定的底物。水解后可游离出邻硝基酚，由于邻硝基酚在碱性条件下呈黄色（ 420毫微米光吸收），所以容易进行比色定量。另外利用这种性质，还可用于分离各种代谢调节突变株。  

In Situ Hybridization Methods for Mouse Whole Mounts and Tissue Sections with and Without Additional -Galactosidase Staining

than 5-bromo-4-chloro-3-indolyl-β-d -galactoside (X-gal). S-gal is advantageous where β-gal activity is limited including early stage mouse embryos. As a result of the increased sensitivity as well as the color compatibility of S-gal, we successfully combined