Catalysis by Cutinase

Fungal cutinase catalyzes hydrolysis of model substrates and in particular p-nitrophenyl esters of short chain fatty acids, providing a convenient spectro-photometric assay for this enzyme activity [101,102,116]. Hydrolysis of model esters by this cutinase showed the high degree of preference of this enzyme for primary alcohol ester hydrolysis. Wax esters and methyl esters of fatty acids were hydrolyzed at low rates. Alkane-2-ol esters were hydrolyzed much more slowly than wax esters and esters of mid-chain secondary alcohols were not 

Fungal cutinases show no free SH groups but have 4 Cys residues, indicating that they are in disulfide linkage [119]. The reaction of the native enzyme with DTE was extremely slow but in the presence of SDS at its CMC rapid reduction could be observed [102]. Reduction of the disulfide bridge resulted in irreversible inactivation of the enzyme and the protein tended to become insoluble. CD spectra of cutinase in the 205-230 nm region, before and after DTE reduc- 

The crystal structure of cutinase from F. solani f. pisi (Fig. 10) indicated that this fungal cutinase constitutes a separate class of enzyme that maybe regarded as a bridge between esterases and lipases in that the free cutinase has a well-de- 

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Figure 1. Mechanism of catalysis by cutinase. (Reproduced with permission from Ref. 16. Copyright 1984 Elsevier/ North Holland Biomedical Press.)...

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