Hybrid sequencing approach applied to human fecal metagenomic clone libraries revealed clones with potential biotechnological applications

PLoS One. 2012;7(10):e47654. doi: 10.1371/journal.pone.0047654. Epub 2012 Oct 17.

Abstract

Natural environments represent an incredible source of microbial genetic diversity. Discovery of novel biomolecules involves biotechnological methods that often require the design and implementation of biochemical assays to screen clone libraries. However, when an assay is applied to thousands of clones, one may eventually end up with very few positive clones which, in most of the cases, have to be "domesticated" for downstream characterization and application, and this makes screening both laborious and expensive. The negative clones, which are not considered by the selected assay, may also have biotechnological potential; however, unfortunately they would remain unexplored. Knowledge of the clone sequences provides important clues about potential biotechnological application of the clones in the library; however, the sequencing of clones one-by-one would be very time-consuming and expensive. In this study, we characterized the first metagenomic clone library from the feces of a healthy human volunteer, using a method based on 454 pyrosequencing coupled with a clone-by-clone Sanger end-sequencing. Instead of whole individual clone sequencing, we sequenced 358 clones in a pool. The medium-large insert (7-15 kb) cloning strategy allowed us to assemble these clones correctly, and to assign the clone ends to maintain the link between the position of a living clone in the library and the annotated contig from the 454 assembly. Finally, we found several open reading frames (ORFs) with previously described potential medical application. The proposed approach allows planning ad-hoc biochemical assays for the clones of interest, and the appropriate sub-cloning strategy for gene expression in suitable vectors/hosts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biotechnology / methods*
  • Enzymes / metabolism
  • Feces / microbiology*
  • Gene Library*
  • Humans
  • Industry
  • Metagenomics*
  • Molecular Sequence Annotation
  • Open Reading Frames / genetics
  • Sequence Analysis, DNA / methods*

Substances

  • Enzymes

Grants and funding

This work was funded by grant CP09/00049 Miguel Servet, Instituto de Salud Carlos III, Spain to GD; by projects SAF2009-13032-C02-01 from the Spanish Ministry for Science and Innovation (MCINN), FU2008-04501-E from Spanish Ministry for Science and Innovation (MCINN) in the frame of ERA-Net PathoGenoMics and Prometeo/2009/092 from Conselleria D’Educació Generalitat Valenciana, Spain, to AM. MD is recipient of a fellowship from Spanish Ministry of Education FPU2010. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.