High-level expression of a neoagarobiose-producing beta-agarase gene from Agarivorans sp. JAMB-A11 in Bacillus subtilis and enzymic properties of the recombinant enzyme.
The structural gene for a neoagarobiose-producing beta-agarase of an Agarivorans isolate was expressed in Bacillus subtilis. High-level production of the recombinant enzyme was achieved corresponding to a level of 1.9 x 10(4) units/l of the culture broth. The efficiency of the production is thus 30-fold greater than that of the original strain. The recombinant enzyme (RagaA11) had a molecular mass of 105 kDa and a specific activity of 371 units/mg. The optimal pH and temperature of the enzyme were 7.5-8.0 and 40 degrees C respectively. The enzyme is an endo-type beta-agarase hydrolysing not only agarose, but also neoagarotetraose, to yield neoagarobiose as the final main product, representing approx. 90 mol% of total products. RagaA11 would be useful for industrial production of neoagarobiose.
Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka 237-0061, Japan.
Yukari
Y
Ohta
Yuji
Y
Hatada
Susumu
S
Ito
Koki
K
Horikoshi
D034241:Alteromonadaceae / Q000201:enzymology*; D001412:Bacillus subtilis / Q000378:metabolism*; D001483:Base Sequence; D002412:Cations; D004187:Disaccharides / Q000096:biosynthesis*; D004795:Enzyme Stability; D005786:Gene Expression Regulation; D006026:Glycoside Hydrolases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010802:Phylogeny; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism
D002412:Cations; D004187:Disaccharides; D011994:Recombinant Proteins; C068544:neoagarobiose; D006026:Glycoside Hydrolases; C019624:agarase