The purification and characterization of a Trichoderma harzianum exochitinase.
A chitinolytic enzyme was purified from the culture filtrate of T. harzianum (T198) by precipitation with ammonium sulphate followed by affinity binding to swollen chitin and release with 10% (v/v) acetic acid. The molecular weight of the enzyme was calculated to be 28 and 27.5 kD by gel filtration chromatography and SDS-PAGE, respectively. The isoelectric point of the enzyme was 7.4. The pH optimum for activity was 3.5 and maximum activity was obtained at 50 degrees C. The enzyme displayed activity on a wide array of chitin substrates of more than two N-acetylglucosamine units in length. HPLC analysis of hydrolysis products demonstrated that the enzyme was an exochitinase releasing N-acetylglucosamine only.
Deane
E E
EE
Department of Life Science, University of Nottingham, UK.
Whipps
J M
JM
Lynch
J M
JM
Peberdy
J F
JF
D000596:Amino Acids / Q000032:analysis; D002241:Carbohydrates / Q000032:analysis; D002688:Chitinases / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D004492:Edetic Acid / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008670:Metals / Q000494:pharmacology; D008970:Molecular Weight; D009994:Osmolar Concentration; D013379:Substrate Specificity; D014242:Trichoderma / Q000201:enzymology*
D000596:Amino Acids; D002241:Carbohydrates; D008670:Metals; D004492:Edetic Acid; D002688:Chitinases