Pollen cutinase

Remarkably, Brassica napus pollen was reported to have a 22 kDa cutinase that cross-reacted with antibodies prepared against F. solani f. pisi cutinase [134]. Although a 22 kDa and a 42 kDa protein that catalyzed hydrolysis of p-nitrophenyl butyrate were found in this pollen, only the former catalyzed cutin hydrolysis. Immunofluorescence microscopic examination suggested that the 22 kDa protein was located in the intine. Since the nature of the catalytic mechanism of this enzyme has not been elucidated, it is not clear whether this represents a serine hydrolase indicating that plants may have serine and thiol cutinases. The role of the pollen enzyme in controlling compatibility remains to be established. 

Kolattukudy PE, Purdy RE, Maiti IB (1981) Cutinases from fungi and pollen. In Lowenstein JM (ed) Methods in enzymology. Academic Press, New York, p 652... 

Kolattukudy PE (1984) Cutinases from fungi and pollen. In Borgstrom B, Brockman H (eds) Lipases. Elsevier Science Publishers, Amsterdam, p 471... 

Cutin. Structural component of the outer lipophilic protective layer (cuticle) of the aerial parts of plants, especially leaves. Suberin serves similar functions in roots and bark. C. is a natural polyester, formed enzymatically from hydroxyfatty acids with 16 and 18 C atoms. o+Hydroxy- and dihydroxyfatty acids, e.g., 10,16-dihydroxypalmitic acid, as well as epoxy- and oxofatty acids, and a,o>-dicarboxylic acids are the main components of cutin. Cutinases (C.-cleaving enzymes) occur especially in pollen and in plant-pathogenic fungi, e.g., Fusarium solani (while rot in potatoes). 

Fig. 23. Electrophoresis of cutinase purified from nasturtium pollen top, scan of the gel stained with Coomassie blue middle and bottom, location of enzymatic activity in the gel (Maiti et al., 1979).

Comparison of Some Properties of Cutinases from Fungi and Pollen... 

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