title: Biochemical characterization of a novel thermophilic α-galactosidase from Talaromyces leycettanus JCM12802 with significant transglycosylation activity.
abstract: Thermophilic α-galactosidases have great potentials in biotechnological and medicinal applications due to their high-temperature activity and specific stability. In this study, a novel α-galactosidase gene of glycoside hydrolase family 27 (aga27A) was cloned from Talaromyces leycettanus JCM12802 and successfully expressed in Pichia pastoris GS115. Purified recombinant Aga27A (rAga27A) was thermophilic and thermotolerant, exhibiting the maximum activity at 70°C and retaining stability at 65°C. Like most fungal α-galactosidases, rAga27A had an acidic pH optimum (pH 4.0) but retained stability over a boarder pH range (pH 3.0-11.0) at 70°C. Moreover, the enzyme exhibited strong resistance to most metal ions and chemicals tested (except for Ag(+) and SDS) and great tolerance to galactose (19 mM). The preferable transglycosylation capacity of rAga27A with various substrates further widens its application spectrum. Thus rAga27A with excellent enzymatic properties will be ideal for applications in various industries, especially for the synthesis of galactooligosaccharides.
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
authors.forename: Caihong
authors.initials: C
authors.lastname: Wang
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China; Biotechnology Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
authors.forename: Rui
authors.initials: R
authors.lastname: Ma
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
authors.forename: Pengjun
authors.initials: P
authors.lastname: Shi
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
authors.forename: Canfang
authors.initials: C
authors.lastname: Niu
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
authors.forename: Huiying
authors.initials: H
authors.lastname: Luo
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China; CAAS-ICRAF Joint Laboratory on Agroforestry and Sustainable Animal Husbandry, Beijing 100193, People's Republic of China.
authors.forename: Peilong
authors.initials: P
authors.lastname: Yang
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China. Electronic address: binyao@caas.cn.
authors.forename: Bin
authors.initials: B
authors.lastname: Yao
mesh_terms: D004795:Enzyme Stability; D005690:Galactose / Q000378:metabolism; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000378:metabolism / Q000494:pharmacology; D009844:Oligosaccharides / Q000096:biosynthesis; D010843:Pichia / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity; D032901:Talaromyces / Q000201:enzymology* / Q000235:genetics; D013696:Temperature; D000519:alpha-Galactosidase / Q000235:genetics / Q000378:metabolism*
chemical_list: D008670:Metals; D009844:Oligosaccharides; D011994:Recombinant Proteins; D000519:alpha-Galactosidase; D005690:Galactose
keywords: Galactose tolerance; Talaromyces leycettanus JCM12802; Thermophilic; Transglycosylation; α-Galactosidase