Abstract
Cell-1 is a host-derived beta-1,4-endoglucanase (Glycohydrolase Family 9 [GHF9]) from the lower termite Reticulitermes flavipes. Here, we report on the heterologous production of Cell-1 using eukaryotic (Baculovirus Expression Vector System; BEVS) and prokaryotic (E. coli) expression systems. The BEVS-expressed enzyme was more readily obtained in solubilized form and more active than the E. coli-expressed enzyme. Km and Vmax values for BEVS-expressed Cell-1 against the model substrate CMC were 0.993% w/v and 1.056 μmol/min/mg. Additional characterization studies on the BEVS-expressed enzyme revealed that it possesses activity comparable to the native enzyme, is optimally active around pH 6.5-7.5 and 50-60°C, is inhibited by EDTA, and displays enhanced activity up to 70°C in the presence of CaCl2. These findings provide a foundation on which to begin subsequent investigations of collaborative digestion by coevolved host and symbiont digestive enzymes from R. flavipes that include GHF7 exoglucanases, GHF1 beta glucosidases, phenol-oxidizing laccases, and others.
Original language | English (US) |
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Pages (from-to) | 147-162 |
Number of pages | 16 |
Journal | Archives of Insect Biochemistry and Physiology |
Volume | 74 |
Issue number | 3 |
DOIs | |
State | Published - Jul 2010 |
Externally published | Yes |
Keywords
- Baculovirus
- Bioethanol
- Endoglucanase
- Feedstock
- GHF9
- Termite
ASJC Scopus subject areas
- Physiology
- Biochemistry
- Insect Science