Bacterial chitinase with phytopathogen control capacity from suppressive soil revealed by functional metagenomics

Autor: Karin Hjort, Annelie Elväng, Flavia Marinelli, I. Presti, Sara Sjöling
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Medicin och hälsovetenskap
Gene Expression
Chitin
Applied Microbiology and Biotechnology
Medical and Health Sciences
chemistry.chemical_compound
Enzyme Stability
Cloning
Molecular
Soil Microbiology
2. Zero hunger
0303 health sciences
biology
Chitinases
Temperature
Soil metagenome
General Medicine
Hydrogen-Ion Concentration
Miljövetenskap
Plant disease
Recombinant Proteins
Fosmid
chitinase
Soil microbiology
Metagenomic library
Biotechnology
DNA
Bacterial
Molecular Sequence Data
terminal restriction fragment length polymorphism (T-RFLP)
Chitinolytic enzyme
Antifungal
Microbiology
Bacterial genetics
Heterologous protein expression
03 medical and health sciences
Environmental Biotechnology
Escherichia coli
Phytopathogen control
suppressive soil
Streptomycetes
030304 developmental biology
Gene Library
Bacteria
030306 microbiology
Fungi
Sequence Analysis
DNA
biology.organism_classification
Protein Structure
Tertiary
Molecular Weight
Mikrobiologi
chemistry
Metagenomics
Chitinase
biology.protein
Environmental Sciences
Zdroj: Applied Microbiology and Biotechnology
Popis: 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. Electronic supplementary material The online version of this article (doi:10.1007/s00253-013-5287-x) contains supplementary material, which is available to authorized users.
Databáze: OpenAIRE
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