TY - JOUR
T1 - Cassava pullulanase and its synergistic debranching action with isoamylase 3 in starch catabolism
AU - Wangpaiboon, Karan
AU - Charoenwongpaiboon, Thanapon
AU - Klaewkla, Methus
AU - Field, Robert A.
AU - Panpetch, Pawinee
N1 - Data availability statement: The original contributions presented in the study are included in the article/Supplementary Material. Further inquiries can be directed to the corresponding author.
Funding information: This research was supported by Thailand Science research and Innovation Fund Chulalongkorn University [BCG66230003 to PP]. KW received a Second Century Fund (C2F) Postdoctoral Fellowship of Chulalongkorn University. This work [Grant No. RGNS 64-014] is also supported by Office of the Permanent Secretary, Ministry of Higher Education, Science, Research and Innovation (OPS MHESI), Thailand Science Research and Innovation (TSRI) and Chulalongkorn University. This research project is supported by grants for development of new faculty Staff, Ratchadaphiseksomphot Fund, Chulalongkorn University.
PY - 2023/1/27
Y1 - 2023/1/27
N2 - Pullulanase (EC 3.2.1.41, PUL), a debranching enzyme belonging to glycoside hydrolase family 13 subfamily 13, catalyses the cleavage of α-1,6 linkages of pullulan and β-limit dextrin. The present work studied PUL from cassava Manihot esculenta Crantz (MePUL) tubers, an important economic crop. The Mepul gene was successfully cloned and expressed in E. coli and rMePUL was biochemically characterised. MePUL was present as monomer and homodimer, as judged by apparent mass of ~ 84 - 197 kDa by gel permeation chromatography analysis. Optimal pH and temperature were at pH 6.0 and 50 °C, and enzyme activity was enhanced by the addition of Ca2+ ions. Pullulan is the most favourable substrate for rMePUL, followed by β-limit dextrin. Additionally, maltooligosaccharides were potential allosteric modulators of rMePUL. Interestingly, short-chain maltooligosaccharides (DP 2 - 4) were significantly revealed at a higher level when rMePUL was mixed with cassava isoamylase 3 (rMeISA3), compared to that of each single enzyme reaction. This suggests that MePUL and MeISA3 debranch β-limit dextrin in a synergistic manner, which represents a major starch catabolising process in dicots. Additionally, subcellular localisation suggested the involvement of MePUL in starch catabolism, which normally takes place in plastids.
AB - Pullulanase (EC 3.2.1.41, PUL), a debranching enzyme belonging to glycoside hydrolase family 13 subfamily 13, catalyses the cleavage of α-1,6 linkages of pullulan and β-limit dextrin. The present work studied PUL from cassava Manihot esculenta Crantz (MePUL) tubers, an important economic crop. The Mepul gene was successfully cloned and expressed in E. coli and rMePUL was biochemically characterised. MePUL was present as monomer and homodimer, as judged by apparent mass of ~ 84 - 197 kDa by gel permeation chromatography analysis. Optimal pH and temperature were at pH 6.0 and 50 °C, and enzyme activity was enhanced by the addition of Ca2+ ions. Pullulan is the most favourable substrate for rMePUL, followed by β-limit dextrin. Additionally, maltooligosaccharides were potential allosteric modulators of rMePUL. Interestingly, short-chain maltooligosaccharides (DP 2 - 4) were significantly revealed at a higher level when rMePUL was mixed with cassava isoamylase 3 (rMeISA3), compared to that of each single enzyme reaction. This suggests that MePUL and MeISA3 debranch β-limit dextrin in a synergistic manner, which represents a major starch catabolising process in dicots. Additionally, subcellular localisation suggested the involvement of MePUL in starch catabolism, which normally takes place in plastids.
KW - cassava (Manihot esculenta Crantz)
KW - debranching enzyme
KW - pullulan
KW - pullulanase
KW - starch
KW - starch degradation
KW - synergistic debranching
UR - http://www.scopus.com/inward/record.url?scp=85147808481&partnerID=8YFLogxK
U2 - 10.3389/fpls.2023.1114215
DO - 10.3389/fpls.2023.1114215
M3 - Article
AN - SCOPUS:85147808481
VL - 14
JO - Frontiers in Plant Science
JF - Frontiers in Plant Science
SN - 1664-462X
M1 - 1114215
ER -