|
KMID : 0545120130230070913
|
|
Journal of Microbiology and Biotechnology
2013 Volume.23 No. 7 p.913 ~ p.922
|
|
|
Molecular Cloning, Overexpression, and Enzymatic Characterization of Glycosyl Hydrolase Family 16 β-Agarase from Marine Bacterium Saccharophagus sp. AG21 in Escherichia coli
|
|
Lee Young-Deuk
Oh Chul-Hong
Mahanama De Zoysa
Kim Hyo-Won
Wickramaarachchige Don Niroshana Wickramaarachchi
Whang Il-Son
Kang Do-Hyung
Lee Je-Hee
|
|
|
Abstract
|
|
|
|
An agar-degrading bacterium was isolated from red seaweed (Gelidium amansii) on a natural seawater agar plate, and identified as Saccharophagus sp. AG21. The β-agarase gene from Saccharophagus sp. AG21 (agy1) was screened by long and accurate (LA)-PCR. The predicted sequence has a 1,908 bp open reading frame encoding 636 amino acids (aa), and includes a glycosyl hydrolase family 16 (GH16) β-agarase module and two carbohydrate binding modules of family 6 (CBM6). The deduced aa sequence showed 93.7% and 84.9% similarity to β-agarase of Saccharophagus degradans and Microbulbifer agarilyticus, respectively. The mature agy1 was cloned and overexpressed as a His-tagged recombinant β-agarase (rAgy1) in Escherichia coli, and had a predicted molecular mass of 69 kDa and an isoelectric point of 4.5. rAgy1 showed optimum activity at 55oC and pH 7.6, and had a specific activity of 85 U/mg. The rAgy1 activity was enhanced by FeSO4 (40%), KCl (34%), and NaCl (34%), compared with the control. The newly identified rAgy1 is a β-agarase, which acts to degrade agarose to neoagarotetraose (NA4) and neoagarohexaose (NA6) and may be useful for applications in the cosmetics, food, bioethanol, and reagent industries.
|
|
|
KEYWORD
|
|
|
Saccharophagus sp.AG21, beta-agarase, GH16, neoagaro-oligosaccharide
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
  
|
|