One of the most interesting bacterial genera concerning the mineral-weathering process remains Collimonas. This genus was previously described as being able to grow at the expense of living fungal hyphae (mycophagy), to hydrolyze chitin (de Boer et al., 2004) and, more recently, to be preferentially associated with fungi (Ma¨nnisto¨ and Ha¨ggblom, 2006; Offre et al., 2007; Uroz et al., 2007).