What are the components required for the initiation of transcription in bacteria?

Components required for initiation of  transcription in bacteria are RNA polymerase is only capable of catalysing the process of elongation. It associates transiently with initiation-factor ($\mathrm{\sigma }$) and termination-factor ($\mathrm{\rho }$) to initiate and terminate the transcription, respectively. A promoter region in DNA and the substrates ribonucleoside triphosphates are required.