There's no vaccine to prevent HIV infection and no cure for AIDS. But it's possible to protect yourself and others from infection. That means educating yourself about HIV and avoiding any behavior that allows HIV-infected fluids â blood, semen, vaginal secretions and breast milk â into your body.hen used to help prevent HIV infection, Truvada is only appropriate if your doctor is certain you don't already have an HIV infection. Your doctor should also test for hepatitis B infection. If you have hepatitis B, your doctor should test your kidney function before prescribing Truvada.
Contact Us. A promoter is a regulatory region of DNA located upstream (towards the 5' region) of of a gene, providing a control point for regulated gene transcription.
1 In negative inducible operons, a regulatory repressor protein is normally bound to the operator, which prevents the transcription of the genes on the operon. 2  If an inducer molecule is present, it binds to the repressor and changes its conformation so that it is unable to bind to the operator. Operator â a segment of DNA that a repressor binds to. 2  It is classically defined in the lac operon as a segment between the promoter and the genes of the operon. 3  In the case of a repressor, the repressor protein physically obstructs the RNA polymerase from transcribing the genes.