We present results of optical phase conjugation experiments in modified DNA (deoxyribonucleic acid) - dye system. The system consisted of a biopolymeric matrix made of DNA blended with cationic surfactant molecule cetyltrimethyl-ammonium chloride (CTMA) and doped with a photochromic dye Disperse Red 1. Results were obtained in a typical degenerate four wave mixing experiment. For sample excitation we used linearly polarized light at a wavelength 514.5 nm, delivered by an argon ion (Ar+) laser. The phase conjugated signal which emerged from the sample had rise and fall time constants of a few milliseconds with an excellent reversibility