Darwin’s evolutionary theory - Common descent

TLS Online TPP Program

#Id: 595

#Unit 2. Cellular Organization

How cro cause lytic cycle- proteolytic cleavage of lambda repressor

 

TLS Online TPP Program

#Id: 596

#Unit 2. Cellular Organization

When DNA is extensively damaged (such as by UV light. RecA protein binds to this damaged, single-stranded DNA, activating the protein's coprotease activity. While bound to DNA, the RecA protein facilitates cleavage and inactivation of the Lex and Lambda repressor. 

TLS Online TPP Program

#Id: 597

#Unit 2. Cellular Organization

Activator cII, Controls the Decision between Lytic and Lysogenic Growth upon Infection of a New Host

TLS Online TPP Program

#Id: 598

#Unit 2. Cellular Organization

Like the Lambda repressor, the cII protein is a transcriptional activator. It binds to a site upstream of a promoter called PRE (for repressor establishment) and stimulates transcription of the cI (repressor) gene from that promoter.

TLS Online TPP Program

#Id: 599

#Unit 2. Cellular Organization

The cI gene is transcribed from PRE when establishing lysogeny and from PRM when maintaining that state. 

PR controls not only lytic genes, but also expression of cII and is thus important in lysogeny as well as lytic development. PL which controls many lytic genes, also controls the cIII gene which helps establish lysogeny

TLS Online TPP Program

#Id: 600

#Unit 2. Cellular Organization