|Figure 1. Number of OTUs as
a function of fractional sequence difference
(OTU cut-off) for the 16S rRNA marker
gene (A) and the rpoB marker gene (B).
Interesting new paper in PLoS One: PLoS ONE: A Comparison of rpoB and 16S rRNA as Markers in Pyrosequencing Studies of Bacterial Diversity
In the paper they test and use PCR amplification and pyrosequencing of the rpoB gene for studies of the diversity of bacteria. Due to the lower level of conservation of rpoB than rRNA genes at the DNA level they focused on proteobacteria. It seems that with a little perseverance once can get PCR for protein coding genes to work reasonably well for even reasonably broad taxonomic groups (not totally new here but I am not aware of too many papers doing this with pyrosequencing). Anyway, the paper is worth a look.
Vos M, Quince C, Pijl AS, de Hollander M, Kowalchuk GA (2012) A Comparison of rpoB and 16S rRNA as Markers in Pyrosequencing Studies of Bacterial Diversity. PLoS ONE 7(2): e30600. doi:10.1371/journal.pone.0030600 Vos, M., Quince, C., Pijl, A., de Hollander, M., & Kowalchuk, G. (2012). A Comparison of rpoB and 16S rRNA as Markers in Pyrosequencing Studies of Bacterial Diversity PLoS ONE, 7 (2) DOI: 10.1371/journal.pone.0030600