A Novel Cyclodextrin Glycosyltransferase from Alkaliphilic Amphibacillus sp. NPST-10: Purification and Properties
نویسندگان
چکیده
Screening for cyclodextrin glycosyltransferase (CGTase)-producing alkaliphilic bacteria from samples collected from hyper saline soda lakes (Wadi Natrun Valley, Egypt), resulted in isolation of potent CGTase producing alkaliphilic bacterium, termed NPST-10. 16S rDNA sequence analysis identified the isolate as Amphibacillus sp. CGTase was purified to homogeneity up to 22.1 fold by starch adsorption and anion exchange chromatography with a yield of 44.7%. The purified enzyme was a monomeric protein with an estimated molecular weight of 92 kDa using SDS-PAGE. Catalytic activities of the enzyme were found to be 88.8 U mg(-1) protein, 20.0 U mg(-1) protein and 11.0 U mg(-1) protein for cyclization, coupling and hydrolytic activities, respectively. The enzyme was stable over a wide pH range from pH 5.0 to 11.0, with a maximal activity at pH 8.0. CGTase exhibited activity over a wide temperature range from 45 °C to 70 °C, with maximal activity at 50 °C and was stable at 30 °C to 55 °C for at least 1 h. Thermal stability of the purified enzyme could be significantly improved in the presence of CaCl(2). K(m) and V(max) values were estimated using soluble starch as a substrate to be 1.7 ± 0.15 mg/mL and 100 ± 2.0 μmol/min, respectively. CGTase was significantly inhibited in the presence of Co(2+), Zn(2+), Cu(2+), Hg(2+), Ba(2+), Cd(2+), and 2-mercaptoethanol. To the best of our knowledge, this is the first report of CGTase production by Amphibacillus sp. The achieved high conversion of insoluble raw corn starch into cyclodextrins (67.2%) with production of mainly β-CD (86.4%), makes Amphibacillus sp. NPST-10 desirable for the cyclodextrin production industry.
منابع مشابه
Purification and some properties of a keratinolytic enzyme from an alkaliphilic Nocardiopsis sp. TOA-1.
A novel alkaliphilic Nocardiopsis sp., strain TOA-1, was isolated from a tile-joint of a bathroom. Strain TOA-1 produced a variety of alkaline hydrolytic enzymes. An alkaline protease, designated NAPase, was purified and characterized. NAPase had a very high keratinolytic activity and high stability under acidic conditions.
متن کاملDraft Genome Sequence of Amphibacillus jilinensis Y1T, a Facultatively Anaerobic, Alkaliphilic and Halotolerant Bacterium
The genus Amphibacillus was established in 1990, and seven additional species were described in the past two decades. Amphibacillus jilinensis Y1(T) is a facultatively anaerobic and alkaliphilic bacterium isolated from a soda lake in China. Here we describe the structural and genetic features of the draft genome about the type strain Y1(T) (3,831,075 bp, with a G+C content of 37.27%). This is t...
متن کاملPurification and Characterization of a Novel Thermostable and Acid Stable α-Amylase from Bacillus Sp. Iranian S1
This study reports the purification and biochemical characterization of thermostable and acidic-pH-stable α-amylase from Bacillus sp. Iranian S1 isolated from the desert soil (Gandom-e-Beryan in Lut desert, Iran). Amylase production was found to be growth associated. Maximum enzyme production was in exponential phase with activity 2.93 U ml-1 at 50°C and pH 5. The enzyme was purified by isoprop...
متن کاملPurification and Properties of a Xylan-Binding Endoxylanase from Alkaliphilic Bacillus sp. Strain K-1 KHANOK RATANAKHANOKCHAI,* KHIN LAY KYU, AND MORAKOT TANTICHAROEN
متن کامل
Single Step Purification of Novel Thermostable and Chelator Resistant Amylase from Bacillus Licheniformis RM44 by Affinity Chromatography
Bacillus licheniformis RM44 was isolated from hot spring near Karachi and screened forthe production of extracellular amylase Amy RM44. Amy RM44 was purified to homogeneityon a single step by affinity chromatography using insoluble corn starch. The molecular weightof Amy RM44 was estimated to be 66 kDa by SDS–PAGE and zymographic analysis. Nine foldpurification was achieved with the specific ac...
متن کامل