Single Molecule Dynamics of Lysozyme Processing Distinguishes Linear and Cross-linked Peptidoglycan Substrates
| Autor: | Issa S. Moody, Patrick C. Sims, Gregory A. Weiss, Brad L. Corso, David E. Seitz, Steven R. Hunt, Larry C. Blaszczak, Philip G. Collins, Yongki Choi |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2012 |
| Předmět: |
chemistry.chemical_classification
Quenching (fluorescence) Nanotubes Carbon Hydrolysis Substrate (chemistry) Glycosidic bond General Chemistry Processivity Peptidoglycan Molecular Dynamics Simulation Biochemistry Catalysis Article chemistry.chemical_compound Crystallography Colloid and Surface Chemistry chemistry Biocatalysis Molecule Bacteriophage T4 Muramidase Lysozyme Linker |
| Popis: | The dynamic processivity of individual T4 lysozyme molecules was monitored in the presence of either linear or cross-linked peptidoglycan substrates. Single-molecule monitoring was accomplished using a novel electronic technique in which lysozyme molecules were tethered to single-walled carbon nanotube field-effect transistors through pyrene linker molecules. The substrate-driven hinge-bending motions of lysozyme induced dynamic electronic signals in the underlying transistor, allowing long-term monitoring of the same molecule without the limitations of optical quenching or bleaching. For both substrates, lysozyme exhibited processive low turnover rates of 20-50 s(-1) and rapid (200-400 s(-1)) nonproductive motions. The latter nonproductive binding events occupied 43% of the enzyme's time in the presence of the cross-linked peptidoglycan but only 7% with the linear substrate. Furthermore, lysozyme catalyzed the hydrolysis of glycosidic bonds to the end of the linear substrate but appeared to sidestep the peptide cross-links to zigzag through the wild-type substrate. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|