| Cocaine's impact on society spans several thousand years, yet its adverse effects due to the toll of addiction have only imposed a global problem during the last hundred years. After cocaine was isolated from its natural source, leaves of a coca plant, it proved to be a "miracle drug" with numerous pharmacological effects. Its potential for abuse quickly became so prevalent that it became one of several drugs targeted by the war on drugs. A standard treatment for cocaine addiction remains elusive though multiple research efforts are currently developing a number of candidates. The majority of pharmacological approaches to treating cocaine addiction offer limited benefits that treat symptoms of addiction and do not curb long term drug seeking behavior once the treatment is over. A number of protein-based therapeutics has shown promise in their ability to hydrolyze cocaine and provide a more pharmacokinetic approach to cocaine addiction. In this thesis, the continued development of a bacterial enzyme - cocaine esterase -- will be explored. More specifically, through PEGylation of CocE, the in vivo activity of the drug has been extended to four days of complete protection against a lethal dose of cocaine in mice, providing the best protection to date. Also, through crystallographic studies and mutation of CocE's primary structure a mutant with the highest velocity of cocaine hydrolysis has been engineered. The results of these studies demonstrate how CocE continues to prove worthy for the application of cocaine addiction treatment. |
