Diversity of Beetle Genes Encoding Novel Plant Cell Wall Degrading Enzymes

Plant cell walls are composed of complex sugars and proteins that need certain enzymes in order to be degraded. Plant cell walls are also the major source of cellulose, which is the world's most vital biopolymer. Thus, plant cell wall degrading enzymes (PCWDEs) are necessary in various biotechnological procedures such as biofuels production and food to waste processing.

The last common ancestor of echinoderms, acorn worms, and chordates was inferred to have the ability to digest and synthesize cellulose, but the current model insects lack genes coding for PCWDEs. Thus, Yannick Pauchet of the University of Exeter, UK, together with his team, investigated this disappearance of genes coding for PCWDEs by examining the sets of RNA molecules of guts of beetles that have different plant diets. They also surveyed Expressed Sequence Tags (ESTs) which are small portions of genes that are publicly available to help scientists identify and locate unknown genes. The scientists were able to characterize 167 new beetle PCWDEs under eight enzyme families.

Based on their results, they found out that these newly discovered enzymes were not present in the model insects with mapped genomes, and also the insect families that produce the enzymes are experiencing complex child-birth dynamics. The initial reported loss of genes coding for PCWDEs was a mere sampling problem. Various beetles, aside from the microorganisms that live in them, are able to produce PCWDEs and could be used as a source of enzymes for utilization in biotechnology.

Read the research article at http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015635.