title: Purification and characterization of a novel alpha-agarase from a Thalassomonas sp.
abstract: An agar-degrading Thalassomonas bacterium, strain JAMB-A33, was isolated from the sediment off Noma Point, Japan, at a depth of 230 m. A novel alpha-agarase from the isolate was purified to homogeneity from cultures containing agar as a carbon source. The molecular mass of the purified enzyme, designated as agaraseA33, was 85 kDa on both SDS-PAGE and gel-filtration chromatography, suggesting that it is a monomer. The optimal pH and temperature for activity were about 8.5 and 45 degrees C, respectively. The enzyme had a specific activity of 40.7 U/mg protein. The pattern of agarose hydrolysis showed that the enzyme is an endo-type alpha-agarase, and the final main product was agarotetraose. The enzyme degraded not only agarose but also agarohexaose, neoagarohexaose, and porphyran.
authors.affiliation: Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima, Yokosuka 237-0061, Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Ohta
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hatada
authors.forename: Masayuki
authors.initials: M
authors.lastname: Miyazaki
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Nogi
authors.forename: Susumu
authors.initials: S
authors.lastname: Ito
authors.forename: Koki
authors.initials: K
authors.lastname: Horikoshi
mesh_terms: D020563:Gammaproteobacteria / Q000145:classification / Q000201:enzymology* / Q000254:growth & development; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D010802:Phylogeny
chemical_list: D006026:Glycoside Hydrolases; C019624:agarase