| Full text | |
| Author(s): |
Total Authors: 2
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| Affiliation: | [1] Univ Sao Paulo, Inst Quim, Dept Bioquim, BR-01498 Sao Paulo - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | PLoS One; v. 10, n. 10 OCT 2 2015. |
| Web of Science Citations: | 2 |
| Abstract | |
The evolution of (beta/alpha)(8) barrel proteins is currently thought to have involved the fusion of two (beta/alpha)(4) half-barrels, thereby conferring stability on the protein structure. After the formation of a whole (beta/alpha)(8) barrel, this structure could evolve and diverge to form fully active enzymes. Interestingly, we show here that isolated (beta/alpha)(4) half-barrels derived from the N- and C-terminal domains of the beta-glucosidase Sf beta gly (Sf beta gly-N: residues 1 to 265; Sf beta gly-C: residues 266 to 509) undergo an activation process, which renders them catalytically active. The rate constants of the activation process were calculated to be 0.029 and 0.032 h(-1) for Sf beta gly-N and Sf beta gly-C, respectively. Moreover, the Sf beta gly-N and Sf beta gly-C activation processes were simultaneous with modifications in their initial structure, which reduced the exposure of their tryptophan residues. Importantly, this activation was also coincident with an increase in the sizes of Sf beta gly-N and Sf beta gly-C particles. These novel observations suggest that the change in catalytic activity associated with the transition from a half to whole (beta/alpha)(8) barrel might also have driven such an evolutionary process. (AU) | |
| FAPESP's process: | 08/55914-9 - Development of beta-glycosidases designed to improve the efficiency of noncomplexed cellulase systems |
| Grantee: | Sandro Roberto Marana |
| Support Opportunities: | Program for Research on Bioenergy (BIOEN) - Thematic Grants |