The DNA from the bacterial community was amplified with the
primers 338fgc (5′-CGC CCG CCG CGC GCG GCG GGC GGG GCG GGG
GCA CGG GGG GAC TCC TAC GGG AGG CAG CAG-3′) (the GC clamp
is underlined) and 518r (5′-ATT ACC GCG GCTGCT GG-3′), which span
the V3 region of the 16S rRNA gene (Ovreas, Forney, Daae, & Torsvik,
1997)