Total synthesis and evaluation of T4 lysozyme activity of two N-acetylmuramic acid derivatives

CHED 510

Kelsey N. Pobanz, kpobanz@ups.edu and Dr. John E. Hanson. Department of Chemistry, University of Puget Sound, 1500 N Warner St., Tacoma, WA 98416
T4 lysozyme, an enzyme produced by T4 bacteriophage, hydrolyzes the β(1-4) glycosidic bond between N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG) in polysaccharides chains of the bacterial cell wall. The T4 lysozyme also requires that NAM be substituted with a peptide side chain in order for hydrolysis to occur. The only available substrate is actual cell wall, which is heterogeneous, preventing detailed, accurate kinetic analysis. Synthesis of a smaller, well-defined and convenient substrate, and the ability to modify the peptide side chain in that substrate, would allow us to study the kinetics and mechanism of T4 lysozyme. O-nitrophenyl and p-nitrophenyl β-glycosides of N-acetylmuramic acid linked to Ala-D-Glu(Lys) peptides were synthesized and purified by HPLC and characterized by NMR. Synthesis of the substrates and activity, analyzed by UV/Vis spectroscopy, of the T4 lysozyme will be discussed.