Is a trp operon an example of positive or negative feedback?

Related questions

• How does the a lac operon switch off?
• How are lac operons regulated?
• What is a lac operon?
• What is a regulatory gene?
• What is the regulatory gene, or the regulatory elements in an operon?
• In bacteria, what binds with the repressor to activate the lac operon?
• Is the lac operon a negative or positive control system?
• What is the function of the lac-A gene in the lac operon?
• What is a repressible operon?
• How does lactose get into an E. coli cell if the lac operon is turned "off" and the cell is not...