Comparative biochemical characterization of three exolytic oligoalginate lyases from Vibrio splendidus reveals complementary substrate scope, temperature, and pH adaptations

Sujit Sadashiv Jagtap, Jan Hendrik Hehemann, Martin F. Polz, Jung Kul Lee, Huimin Zhao

Research output: Contribution to journalArticle

Abstract

Marine microbes use alginate lyases to degrade and catabolize alginate, a major cell wall matrix polysaccharide of brown seaweeds. Microbes frequently contain multiple, apparently redundant alginate lyases, raising the question of whether these enzymes have complementary functions. We report here on the molecular cloning and functional characterization of three exotype oligoalginate lyases (OalA, OalB, and OalC) from Vibrio splendidus 12B01 (12B01), a marine bacterioplankton species. OalA was most active at 16°C, had a pH optimum of 6.5, and displayed activities toward poly-β-D-mannuronate [poly(M)] and poly-α-L-guluronate [poly(G)], indicating that it is a bifunctional enzyme. OalB and OalC were most active at 30 and 35°C, had pH optima of 7.0 and 7.5, and degraded poly(M·G) and poly(M), respectively. Detailed kinetic analyses of oligoalginate lyases with poly(G), poly(M), and poly(M·G) and sodium alginate as substrates demonstrated that OalA and OalC preferred poly(M), whereas OalB preferred poly(M·G). The catalytic efficiency (kcat/Km) of OalA against poly(M) increased with decreasing size of the substrate. OalA showed kcat/Km from 2,130 mg-1 ml s-1 for the trisaccharide to 224 mg-1 ml s-1 for larger oligomers of ~50 residues, and 50.5 mg-1 ml s-1 for high-molecular-weight alginate. Although OalA was most active on the trisaccharide, OalB and OalC preferred dimers. Taken together, our results indicate that these three Oals have complementary substrate scopes and temperature and pH adaptations.

Original languageEnglish (US)
Pages (from-to)4207-4214
Number of pages8
JournalApplied and environmental microbiology
Volume80
Issue number14
DOIs
StatePublished - 2014

ASJC Scopus subject areas

  • Biotechnology
  • Food Science
  • Applied Microbiology and Biotechnology
  • Ecology

Fingerprint Dive into the research topics of 'Comparative biochemical characterization of three exolytic oligoalginate lyases from Vibrio splendidus reveals complementary substrate scope, temperature, and pH adaptations'. Together they form a unique fingerprint.

  • Cite this