Bacterial chitinase with phytopathogen control capacity from suppressive soil revealed by functional metagenomics
2014 (English)In: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 98, no 6, 2819-2828 p.Article in journal (Refereed) Published
Plant disease caused by fungal pathogens results in vast crop damage globally. Microbial communities of soil that is suppressive to fungal crop disease provide a source for the identification of novel enzymes functioning as bioshields against plant pathogens. In this study, we targeted chitin-degrading enzymes of the uncultured bacterial community through a functional metagenomics approach, using a fosmid library of a suppressive soil metagenome. We identified a novel bacterial chitinase, Chi18H8, with antifungal activity against several important crop pathogens. Sequence analyses show that the chi18H8 gene encodes a 425-amino acid protein of 46 kDa with an N-terminal signal peptide, a catalytic domain with the conserved active site F175DGIDIDWE183, and a chitinase insertion domain. Chi18H8 was expressed (pGEX-6P-3 vector) in Escherichia coli and purified. Enzyme characterization shows that Chi18H8 has a prevalent chitobiosidase activity with a maximum activity at 35 °C at pH lower than 6, suggesting a role as exochitinase on native chitin. To our knowledge, Chi18H8 is the first chitinase isolated from a metagenome library obtained in pure form and which has the potential to be used as a candidate agent for controlling fungal crop diseases. Furthermore, Chi18H8 may also answer to the demand for novel chitin-degrading enzymes for a broad range of other industrial processes and medical purposes.
Place, publisher, year, edition, pages
2014. Vol. 98, no 6, 2819-2828 p.
metagenomic library, chitinase, terminal restriction fragment length polymorphism (T-RFLP), Streptomycetes, suppressive soil
Microbiology Environmental Sciences
Research subject Baltic and East European studies; Environmental Studies
IdentifiersURN: urn:nbn:se:sh:diva-20023DOI: 10.1007/s00253-013-5287-xISI: 000332108100041PubMedID: 24121932ScopusID: 2-s2.0-84905997072Local ID: 47/42/2011OAI: oai:DiVA.org:sh-20023DiVA: diva2:659271
ProjectsMetaexplore - metagenomics for bioexploration
FunderEU, FP7, Seventh Framework Programme, KBBE-222625The Foundation for Baltic and East European Studies
Electronic supplementary material2013-10-242013-10-242016-10-07Bibliographically approved