Cutinase fungal

The purified fungal cutinase fiom F. oxysporum f. sp. pisi was kindly provided by Prof. C.M.J. Sagt in Utrecht University. The commercial product of esterase firom Candida cylindracea was purchased fi om Boehringer Mannheim (Germany). The enzymatic degradation of DEP... 

Fig. 2. Time-course variation in the amount of chemical compounds produced during DEP degradation by fungal cutinase (10 mg 1 ) (a) and yeast esterase (100 mg F) (b), analyzed through GC/MS chromatography.

Isolation of Fungal Cutinases and their Molecular Properties... 

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-... 

Fig. 12. Schematic representation of how the plant cuticle induces cutinase in a fungal spore... 

The biopolymer cutin is a major constituent of the plant cuticle that provides a protective covering for plants (1,2). At the time of infection, a number of fungal pathogens secrete an extracellular hydrolytic enzyme, cutinase, which facilitates the degradation of cutin into its constituent Ci6-to Cig-length hydroxy fatty acids (3,4). Since the enzyme is believed to... 

Apart from proteases, cutinases and lipases were demonstrated to hydrolyse PA. Hydrolysis of PA with a lipase (not further specified) was confirmed by using FTIR analysis and dye-binding assays [32]. Several reports have assessed the potential of cutinases for PA functionalisation, and a fungal cutinase from F. solani was successfully genetically engineered towards higher activity on a PA oligomer and PA [23-25]. 

Various bacterial, fungal and plant lipases have been described to hydrolyze PET (Table 15.1). Lipases catalyze the hydrolysis of long chain water insoluble triglycerides and, unlike cutinase they are interfacially activated in the presence of a water-lipid interface [63-65]. The active site of lipases is covered with a peptide segment called lid while upon opening the active site becomes accessible to the substrate. Consequently, it as been indicated that PET hydrolysis by lipase can be improved in the presence of detergents [55, 66]. Apart from typical lipases and cutinases, other esterases have been shown to hydrolyze PET. Nevertheless, it is not quite clear yet what constitues a PET-hydrolase. On the one hand a comprehensive comparison of all reported enzymes on typical lipase and cutinase substrates in addition to PET is not available. On the other hand, apart from the active site architecture and specificities on water soluble substrates, the adsorption behavior onto polymers will also play a major role. 

Benomyl has been frequently reported to be more effective than MBC although both compounds exhibited similar toxic effect. Kdller et al. (1982) found that benomyl, but not MBC inhibits cutinase from Fusarium solani by the reaction of butylisocyanate and prevents under controlled conditions of a bioassay, the fungal penetration into its host suggesting the possibility of a dual mode of action for this fungicide. 

Studied. Instead, the spray program was conducted In alternate weeks for an entire season and results were positive. It Is likely that antipenetrant chemicals which inhibit cutinase will work effectively if combined with a low level of a classical fungicide. In this manner, the bulk of the fungal spores will not be able to penetrate and some which might penetrate through some breach in the cuticular barrier can be prevented from setting up infection by the fungicide. 

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