Construction of minimum size cellulase (Cel5Z) from Pectobacterium chrysanthemi PY35 by removal of the C-terminal region.
Pectobacterium chrysanthemi PY35 secretes the endoglucanase Cel5Z, an enzyme of the glycoside hydrolase family 5. Cel5Z is a 426 amino acid, signal peptide (SP)-containing protein composed of two domains: a large N-terminal catalytic domain (CD; 291 amino acids) and a small C-terminal cellulose binding domain (CBD; 62 amino acids). These two domains are separated by a 30 amino acid linker region (LR). A truncated cel5Z gene was constructed with the addition of a nonsense mutation that removes the C-terminal region of the protein. A truncated Cel5Z protein, consisting of 280 amino acid residues, functioned as a mature enzyme despite the absence of the SP, 11 amino acid CD, LR, and CBD region. In fact, this truncated Cel5Z protein showed an enzymatic activity 80% higher than that of full-length Cel5Z. However, cellulase activity was undetectable in mature Cel5Z proteins truncated to less than 280 amino acids.
Lim
Woo Jin
WJ
Division of Applied Life Science, Gyeongsang National University, Chinju, 660-701, Korea.
Hong
Su Young
SY
An
Chang Long
CL
Cho
Kye Man
KM
Choi
Byoung Rock
BR
Kim
Young Kyun
YK
An
Jin Mee
JM
Kang
Jung Mi
JM
Lee
Sun Mi
SM
Cho
Soo Jeong
SJ
Kim
Hoon
H
Yun
Han Dae
HD
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D001483:Base Sequence; D044602:Cellulases / Q000737:chemistry* / Q000378:metabolism*; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D016974:Dickeya chrysanthemi / Q000201:enzymology*; D015870:Gene Expression; D008969:Molecular Sequence Data; D011487:Protein Conformation; D015202:Protein Engineering
D001426:Bacterial Proteins; D044602:Cellulases