Mining of unexplored habitats for novel chitinases - chiA as a helper gene proxy in metagenomics

Mariana Silvia Cretoiu, Anna Maria Kielak, Waleed Abu Al-Soud, Søren Johannes Sørensen, Jan Dirk van Elsas

Research output: Contribution to journalJournal articleResearchpeer-review

36 Citations (Scopus)

Abstract

The main objective of this study was to assess the abundance and diversity of chitin-degrading microbial communities in ten terrestrial and aquatic habitats in order to provide guidance to the subsequent exploration of such environments for novel chitinolytic enzymes. A combined protocol which encompassed (1) classical overall enzymatic assays, (2) chiA gene abundance measurement by qPCR, (3) chiA gene pyrosequencing, and (4) chiA gene-based PCR-DGGE was used. The chiA gene pyrosequencing is unprecedented, as it is the first massive parallel sequencing of this gene. The data obtained showed the existence across habitats of core bacterial communities responsible for chitin assimilation irrespective of ecosystem origin. Conversely, there were habitat-specific differences. In addition, a suite of sequences were obtained that are as yet unregistered in the chitinase database. In terms of chiA gene abundance and diversity, typical low-abundance/diversity versus high-abundance/diversity habitats was distinguished. From the combined data, we selected chitin-amended agricultural soil, the rhizosphere of the Arctic plant Oxyria digyna and the freshwater sponge Ephydatia fluviatilis as the most promising habitats for subsequent bioexploration. Thus, the screening strategy used is proposed as a guide for further metagenomics-based exploration of the selected habitats.
Original languageEnglish
JournalApplied Microbiology and Biotechnology
Volume94
Issue number5
Pages (from-to)1347-1358
Number of pages12
ISSN0175-7598
DOIs
Publication statusPublished - 2012

Keywords

  • Animals
  • Chitinase
  • Cluster Analysis
  • DNA, Bacterial
  • Denaturing Gradient Gel Electrophoresis
  • Ecosystem
  • Environmental Microbiology
  • Genes, Bacterial
  • Genetic Variation
  • Metagenome
  • Metagenomics
  • Polygonaceae
  • Polymerase Chain Reaction
  • Porifera
  • Sequence Analysis, DNA

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