caa a22 4500 605504695 CHVBK 20210128100617.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s00253-015-6889-2 doi (NATIONALLICENCE)springer-10.1007/s00253-015-6889-2 Improvement in the thermostability of a type A feruloyl esterase, AuFaeA, from Aspergillus usamii by iterative saturation mutagenesis [Elektronische Daten] [Xin Yin, Jian-Fang Li, Chun-Juan Wang, Die Hu, Qin Wu, Ying Gu, Min-Chen Wu] Feruloyl or ferulic acid esterase (Fae, EC 3.1.1.73) catalyzes the hydrolysis of ester bonds between polysaccharides and phenolic acid compounds in xylan side chain. In this study, the thermostability of a type A feruloyl esterase (AuFaeA) from Aspergillus usamii was increased by iterative saturation mutagenesis (ISM). Two amino acids, Ser33 and Asn92, were selected for saturation mutagenesis according to the B-factors analyzed by B-FITTER software and ΔΔG values predicted by PoPMuSiC algorithm. After screening the saturation mutagenesis libraries constructed in Pichia pastoris, 15 promising variants were obtained. The best variant S33E/N92-4 (S33E/N92R) produced a T m value of 44.5°C, the half-lives (t 1/2) of 35 and 198min at 55 and 50°C, respectively, corresponding to a 4.7°C, 2.33- and 3.96-fold improvement compared to the wild type. Additionally, the best S33 variant S33-6 (S33E) was thermostable at 50°C with a t 1/2 of 82min, which was 32min longer than that of the wild type. All the screened S33E/N92 variants were more thermostable than the best S33 variant S33-6 (S33E). This work would contribute to the further studies on higher thermostability modification of type A feruloyl esterases, especially those from fungi. The thermostable feruloyl esterase variants were expected to be potential candidates for industrial application in prompting the enzymic degradation of plant biomass materials at elevated temperatures. Springer-Verlag Berlin Heidelberg, 2015 Feruloyl esterase nationallicence Aspergillus usamii nationallicence Thermostability nationallicence Iterative saturation mutagenesis nationallicence Yin Xin Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut Li Jian-Fang State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut Wang Chun-Juan State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut Hu Die Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut Wu Qin Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut Gu Ying Wuxi Medical School, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut Wu Min-Chen Wuxi Medical School, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/23(2015-12-01), 10047-10056 0175-7598 99:23<10047 2015 99 253 https://doi.org/10.1007/s00253-015-6889-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00253-015-6889-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yin Xin Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut NATIONALLICENCE 700 1- Li Jian-Fang State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut NATIONALLICENCE 700 1- Wang Chun-Juan State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut NATIONALLICENCE 700 1- Hu Die Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut NATIONALLICENCE 700 1- Wu Qin Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut NATIONALLICENCE 700 1- Gu Ying Wuxi Medical School, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut NATIONALLICENCE 700 1- Wu Min-Chen Wuxi Medical School, Jiangnan University, 1800 Lihu Road, 214122, Wuxi, China aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/23(2015-12-01), 10047-10056 0175-7598 99:23<10047 2015 99 253