title: Enantioselective Resolution of γ-Lactam by a Novel Thermostable Type II (+)-γ-Lactamase from the Hyperthermophilic Archaeon Aeropyrum pernix.
abstract: A thermostable formamidase from the aerobic hyperthermophilic archaeon Aeropyrum pernix was revealed a novel type II (+)-γ-lactamase. This type II (+)-γ-lactamase is only composed of 377 amino acid residues, in contrast to another thermostable (+)-γ-lactamase from Sulfolobus solfataricus with 504 amino acid residues (type I). It is interesting that there are low identities between these two (+)-γ-lactamases, and herein, we further proved that at least two types of (+)-γ-lactamases exist in nature due to enzyme promiscuity. The gene of this thermostable (+)-γ-lactamase was cloned, functionally expressed in Escherichia coli BL21, and purified by a simple yet effective heat treatment method. It showed incredible thermostability, retaining 100% of its activity after 12 h at 100 °C. The optimum temperature for this enzyme was supposed to be more than 100 °C, and the optimum pH for this enzyme was about 9.0. The lactamase maintained its activity in the presence of most metal ions, except for Cu(2+). This thermo- and alkaline-tolerant (+)-γ-lactamase presents promising properties for the industrial application. Specifically, it could be used for the production of chirally pure (-)-γ-lactam for the synthesis of well-known carbocyclic nucleosides like abacavir and peramivir. The optical purity of the chiral product reached over 97% enantiomeric excess.
authors: State Key Laboratory of Chemical Resources Engineering, Beijing University of Chemical Technology, 100029, Beijing, People's Republic of China.
authors: Lu
authors: L
authors: Ren
authors: Shaozhou
authors: S
authors: Zhu
authors: Ying
authors: Y
authors: Shi
authors: Shuahua
authors: S
authors: Gao
authors: Guojun
authors: G
authors: Zheng
mesh_terms: D041522:Aeropyrum / Q000201:enzymology*; D000581:Amidohydrolases / Q000737:chemistry* / Q000378:metabolism; D019843:Archaeal Proteins / Q000737:chemistry* / Q000378:metabolism; D004795:Enzyme Stability; D006358:Hot Temperature; D007769:Lactams / Q000737:chemistry* / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D019843:Archaeal Proteins; D007769:Lactams; D000581:Amidohydrolases; C401943:gamma-lactamase