title: Biochemical characterization of thermophilic dextranase from a thermophilic bacterium, Thermoanaerobacter pseudethanolicus.
abstract: TPDex, a putative dextranase from Thermoanaerobacter pseudethanolicus, was purified as a single 70 kDa band of 7.37 U/mg. Its optimum pH was 5.2 and the enzyme was stable between pH 3.1 and 8.5 at 70 degrees C. A half-life comparison showed that TPDex was stable for 7.4 h at 70 degrees C, whereas Chaetominum dextranase (CEDex), currently used as a dextranase for sugar milling, was stable at 55 degrees C. TPDex showed broad dextranase activity regardless of dextran types, including dextran T2000, 742CB dextran, and alternan. TPDex showed the highest thermostability among the characterized dextranases, and may be a suitable enzyme for use in sugar manufacture without decreased temperature.
authors.affiliation: Infection Control Material Research Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 580-185, Korea.
authors.forename: Tae-Soon
authors.initials: TS
authors.lastname: Park
authors.forename: Hyung Jae
authors.initials: HJ
authors.lastname: Jeong
authors.forename: Jin-A
authors.initials: JA
authors.lastname: Ko
authors.forename: Young Bae
authors.initials: YB
authors.lastname: Ryu
authors.forename: Su-Jin
authors.initials: SJ
authors.lastname: Park
authors.forename: Doman
authors.initials: D
authors.lastname: Kim
authors.forename: Young-Min
authors.initials: YM
authors.lastname: Kim
authors.forename: Woo Song
authors.initials: WS
authors.lastname: Lee
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D003910:Dextranase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004795:Enzyme Stability; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D013379:Substrate Specificity; D046968:Thermoanaerobacter / Q000737:chemistry / Q000201:enzymology* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D003910:Dextranase