Adsorption Kinetics of Wild Type and Two Synthetic Stability Mutants of T4 Phage Lysozyme at Silanized Silica Surfaces

✍ Scribed by Brijesh Singla; Viwat Krisdhasima; Joseph McGuire

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 120 KB
• Volume: 182
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1996.0463

✦ Synopsis

NOTE

Adsorption Kinetics of Wild Type and Two Synthetic Stability Mutants of T4 Phage Lysozyme at Silanized Silica Surfaces protein than the wild type (12). A mutant with tryptophan substituted for isoleucine at the same position (I3W) was selected as it is one of the least The adsorption kinetics exhibited by the wild type and two stable lysozymes synthesized to date (12). The structural stability of each synthetic stability mutants of bacteriophage T4 lysozyme at silanmutant was quantified by DDG: the difference between the free energy of ized silica surfaces were monitored with in situ ellipsometry. Muunfolding of the mutant protein and that of the wild type at the melting tant lysozymes purified from Escherichia coli strain RRI were temperature of the wild type: DDG Å /1.2 kcal/mol at pH 6.5 for I3C, produced by substitution of the isoleucine at amino acid position and 02.8 kcal/mol at pH 6.5 for I3W (12, 13). These proteins were used three with cysteine and tryptophan, yielding proteins of greater in earlier work on T4L adsorption (9, 11). A summary of the molecular and lower thermal stability than that of the wild type. Adsorption properties of T4L relevant to its surface behavior was provided in that kinetics were measured over a period of 8 h and interpreted with work. reference to mechanisms allowing for binding into one of two states, characterized by different binding strengths. Each interpre-MATERIALS AND METHODS tation suggested that a protein of lower structural stability would more readily undergo a structural change at the interface, all other things being equal, and this change was more pronounced on hy-Proteins and Surfaces drophilic than on hydrophobic surfaces.