Title : Crystal structure and functional characterization of a cold-active acetyl xylan esterase (PbAcE) from psychrophilic soil microbe Paenibacillus sp - Park_2018_PLoS.One_13_e0206260 |
Author(s) : Park SH , Yoo W , Lee CW , Jeong CS , Shin SC , Kim HW , Park H , Kim KK , Kim TD , Lee JH |
Ref : PLoS ONE , 13 :e0206260 , 2018 |
Abstract :
Cold-active acetyl xylan esterases allow for reduced bioreactor heating costs in bioenergy production. Here, we isolated and characterized a cold-active acetyl xylan esterase (PbAcE) from the psychrophilic soil microbe Paenibacillus sp. R4. The enzyme hydrolyzes glucose penta-acetate and xylan acetate, reversibly producing acetyl xylan from xylan, and it shows higher activity at 4 degrees C than at 25 degrees C. We solved the crystal structure of PbAcE at 2.1-A resolution to investigate its active site and the reason for its low-temperature activity. Structural analysis showed that PbAcE forms a hexamer with a central substrate binding tunnel, and the inter-subunit interactions are relatively weak compared with those of its mesophilic and thermophilic homologs. PbAcE also has a shorter loop and different residue composition in the beta4-alpha3 and beta5-alpha4 regions near the substrate binding site. Flexible subunit movements and different active site loop conformations may enable the strong low-temperature activity and broad substrate specificity of PbAcE. In addition, PbAcE was found to have strong activity against antibiotic compound substrates, such as cefotaxime and 7-amino cephalosporanic acid (7-ACA). In conclusion, the PbAcE structure and our biochemical results provide the first example of a cold-active acetyl xylan esterase and a starting template for structure-based protein engineering. |
PubMedSearch : Park_2018_PLoS.One_13_e0206260 |
PubMedID: 30379876 |
Gene_locus related to this paper: 9mico-6AGQ |
Substrate | 7-Aminocephalosporanic-acid |
Gene_locus | 9mico-6AGQ |
Family | Acetyl-esterase_deacetylase |
Structure | 6AGQ |
Park SH, Yoo W, Lee CW, Jeong CS, Shin SC, Kim HW, Park H, Kim KK, Kim TD, Lee JH (2018)
Crystal structure and functional characterization of a cold-active acetyl xylan esterase (PbAcE) from psychrophilic soil microbe Paenibacillus sp
PLoS ONE
13 :e0206260
Park SH, Yoo W, Lee CW, Jeong CS, Shin SC, Kim HW, Park H, Kim KK, Kim TD, Lee JH (2018)
PLoS ONE
13 :e0206260