title: A novel thermostable, acidophilic alpha-amylase from a new thermophilic "Bacillus sp. Ferdowsicous" isolated from Ferdows hot mineral spring in Iran: Purification and biochemical characterization.
abstract: This paper describes the purification and characterization of a novel acidophile alpha-amylase from newly isolated Bacillus sp. Ferdowsicous. The enzyme displayed a molecular weight of 53 kDa and it was stable over a range of pH from 3.5 to 7 with an optimum around 4.5. The optimum temperature for activity was found to be around 70 degrees C and the enzyme remained active to more than 75% up to 75 degrees C for 45 min. The enzyme activity was decreased by Zn(2+)and EDTA but inhibited by Hg(2+), whereas the activity was increased by approximately 15% by Ba(2+) and Fe(2+). Na(+), Mg(2+), K(+), Ca(2+), PMSF, Triton X-100 and beta-mercaptoethanol had any considerable effect on its activity. The enzyme activity on the amylose as substrate was 1.98 times greater than amylopectin. Partial N-terminal sequencing demonstrated no significant similarity with other known alpha-amylases, indicating that the presented enzyme was new. Considering its promising properties, this enzyme can find potential applications in the food industry as well as in laundry detergents.
authors.affiliation: Department of Chemistry, Faculty of Sciences, Ferdowsi University of Mashhad, Azadi sq., Mashhad, Iran. Asood_a@yahoo.com
authors.forename: Ahmad
authors.initials: A
authors.lastname: Asoodeh
authors.forename: JamshidKhan
authors.initials: J
authors.lastname: Chamani
authors.forename: Milad
authors.initials: M
authors.lastname: Lagzian
mesh_terms: D000143:Acids / Q000378:metabolism; D000595:Amino Acid Sequence; D001407:Bacillus / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D002855:Chromatography, Thin Layer; D003470:Culture Media / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004795:Enzyme Stability / Q000187:drug effects; D045482:Hot Springs / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007477:Ions; D007492:Iran; D008670:Metals / Q000494:pharmacology; D008903:Minerals; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013379:Substrate Specificity / Q000187:drug effects; D013696:Temperature; D000516:alpha-Amylases / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D000143:Acids; D003470:Culture Media; D004791:Enzyme Inhibitors; D007477:Ions; D008670:Metals; D008903:Minerals; D012336:RNA, Ribosomal, 16S; D000516:alpha-Amylases