ICChI, a glycosylated chitinase from the latex of Ipomoea carnea

A multi-functional enzyme ICChI with chitinase/lysozyme/exochitinase activity from the latex of Ipomoea carnea subsp. fistulosa was purified to homogeneity using ammonium sulphate precipitation, hydrophobic interaction and size exclusion chromatography. The enzyme is glycosylated (14–15%), has a molecular mass of 34.94 kDa (MALDI–TOF) and an isoelectric point of pH 5.3. The enzyme is stable in pH range 5.0– 9.0, 80 C and the optimal activity is observed at pH 6.0 and 60 C. Using p-nitrophenyl-N-acetyl-b-D-glucosaminide, the kinetic parameters Km, Vmax, Kcat and specificity constant of the enzyme were calculated as 0.5 mM, 2.5 � 10