Characterization of AlgMsp, an Alginate Lyase from Microbulbifer sp. 6532A

Published

November 19, 2014

Author(s)

Jeffrey W. Hudgens, Steven M. Swift, Ryan D. Heselpoth, Patrick M. Bales, Daniel C. Nelson

Abstract

Alginate is a polysaccharide produced by certain seaweeds and bacteria that consists of mannuronic acid and guluronic acid residues. Seaweed alginate is used in food and industrial chemical processes, while the biosynthesis of bacterial alginate is associated with pathogenic Pseudomonas aeruginosa. Alginate lyases cleave this polysaccharide into short oligo-uronates and thus have the potential to be utilized for both industrial and medicinal applications. An alginate lyase gene, algMsp, from Microbulbifer sp. 6532A, was synthesized as an E.coli codon-optimized clone. The resulting 37 kDa recombinant protein, AlgMsp, was expressed, purified and characterized. The alginate lyase displayed highest activity at pH 8 and 0.2 M NaCl. Activity of the alginate lyase was greatest at 50°C; however the enzyme was not stable over time when incubated at 50°C. The alginate lyase was still highly active at 25°C and displayed little or no loss of activity after 24 hours at 25°C. The activity of AlgMsp was not dependent on the presence of divalent cations. Comparing activity of the lyase against polymannuronic acid and polyguluronic acid substrates showed higher specific activity towards polymannuronic acid. However, AlgMSP exhibited greater binding affinity to the polyguluronic acid substrate. Prolonged AlgMsp-mediated degradation of alginate produced dimer, trimer, tetramer, and pentamer oligo-uronates.

Citation

PLoS One

Volume

9

Issue

11

Pub Type

Journals

Download Paper

https://doi.org/10.1371/journal.pone.0112939

Keywords

alginate, lyase, polysaccharide degradation, polymannuronic acid, polyguluronic acid, oligo-uronates, Microbulbifer

Citation

Hudgens, J. , Swift, S. , , R. , , P. and , D. (2014), Characterization of AlgMsp, an Alginate Lyase from Microbulbifer sp. 6532A, PLoS One, [online], https://doi.org/10.1371/journal.pone.0112939 (Accessed April 24, 2024)