Transcription inLactobacillaceae.DNA-Dependent RNA Polymerase fromLactobacillus caseiIsolation of Transcription Factor y

Abstract

Purified DNA-dependent RNA polymerase [EC 2.7.7.6] from L. casei shows a subunit pattern similar to that of other prokaryotic RNA polymerases. A polypeptide .gamma. (MW = 28,000) with unknown function is tightly bound to about half of the polymerase molecules. A 2nd additional polypeptide (MW = 80,000), already known from L. curvatus, is only present in a fraction of the polymerase molecules. It stimulates transcription of holoenzyme on phage DNA about twice. An isolation procedure for native y is described.