Biochemical and Molecular Characterisation of Pectate Lyase in Ripening Nangka (AAB) Bananas

Biochemical and molecular analysis were carried on Nangka (AAB) banana, a cooking variety banana which is widely distributed in Malaysia. Analysis was focused on pectate lyase which is a cell wall hydrolase enzyme. The enzyme was assayed from crude extract to measure its activity in pulp softening during ripening of Nangka banana. Pectate lyase showed trends of increasing activity which may contribute to cell wall degradation during ripening. This may give insight into the function or the redundancy of pectate lyase enzymes in pulp softening during ripening. Total DNA was extracted from the pulp and pectate lyase gene was amplified and sequenced. Further characterisation of the isolated gene using bioinformatics tools showed more than 90% homology with PL1 gene from 'Williams' (AAA) cultivar and 'Dwarf Cavendish' (AAA).