Abstract
The effect of lipophilization on the structure-function and stability of Mucor miehei aspartyl proteinase (MMP) was examined. Modification of approximately 3 and 2 e-amino groups in MMP with caproyl and myristoyl chloride, respectively, decreased the proteolytic activity (PA) and milk-clotting activity (MC) of the enzyme; differential reduction in these activities was manifest as increased MC/PA. Lipophilized MMP also showed significantly higher thermal, kinetic and conformational stability. Interaction between fatty acids and proteinase appeared to be ionic in nature, as evidenced by increased relative electrophoretic (cathodic) mobility. Attachment of the fatty acid ligands was shown to increase both aliphatic and aromatic hydrophobicity of MMP as indicated by the hydrophobic fluorescent probes cis-parinaric acid and l-anilino-8-naphthalenesulfonate. Lipo-philization-induced changes in functional properties were accompanied by altered secondary and tertiary structure as reflected by far-UV and near- UV circular dichroism spectra, respectively. Results of this study suggesed that high MC/PA may be related to high hydrophobicity in aspartyl proteinases.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.