The extraction of undecaprenol from sumac leaves
Bacterial cells are fortified by an outer layer of peptidoglycan and lipid II is the key precursor molecule in the biosynthesis of peptidoglycan. Lipid II is comprised of several units: a disaccharide moiety, a pentapeptide, and a C55 undecaprenyl chain, which attaches to the disaccharide via a pyrophosphate linker. Since lipid II plays a key role in providing structure and integrity to bacterial cells, it is an attractive target for the development of novel antimicrobial agents. Such studies require the ability to synthesize lipid II and its analogues. However, one of the limitations to synthesizing lipid II is the preparation of the C55 lipid chain. While this molecule is difficult to synthesize, its immediate precursor, undecaprenol (C55-OH) can be extracted from sumac leaves. In this project, we describe the isolation of undecaprenol from the leaves of the sumac tree (Rhus typhina) and its purification by HPLC. At the conclusion of the procedure, roughly 20 mg of undecaprenol was collected. Two major results of the project are presented: first, the development of a simple method to extract this important compound from an abundant and renewable source; and second, the observation of the instability of undecaprenol.