This chapter discusses regulated transcription in a complete ribosome-free in vitro system of Escherichia coli. In studying transcription regulation, however, it is simpler to analyze nascent RNA rather than protein products. A new method has been developed in which cell extract (S-150)-driven DNA-dependent RNA synthesis can be directly monitored. The S-150 is the supernatant of 150,000 g centrifugation of the previously mentioned S-30, and it is devoid of ribosomes and the membrane fraction. The S-150 of Escherichia coli has been proven to contain various cytosolic proteins as well as RNA polymerase. The S-150-dependent transcription system is easy to prepare, and yet, it is effective in studying transcription regulation, especially when unidentified cytosolic components are involved. S-150 is a cell extract generally devoid of membrane and ribosome material. S-150 contains no endogenous cAMP and sufficient CRP (cAMP receptor protein) molecules. Series: Methods in Enzymology (Book 274) Hardcover: 566 pages Publisher: Academic Press; Language: English ISBN-10: 0121821757 ISBN-13: 978-0121821753 Product Dimensions: 1.2 x 6.5 x 9.5 inches Link Download http://nitroflare.com/view/E49B5E1E8E3DA39https://drive.google.com/drive/folders/1yLBzZ1rSQoNjmWeJTZ3WGQHg04L1