Identification of microbiota associated with Pectinatella magnifica in South Bohemia

The bacterial diversity of Pectinatella magnifica colonies sampled from pounds in South Bohemia during the summer of 2012 was investigated. The bacterial counts determined after cultivation on modified yeast extract-tryptone agar (Oxoid) supplemented with glucose (1 g L⁻¹) varied from 4.22 to 6.61 and from 1.30 to 6.85 log CFU/g for aerobes and anaerobes, respectively. Higher counts were found in the superficial structures of Pectinatella colonies than in the inner gelled mass. Neither a trend in bacterial numbers at the individual site during the season, nor correlations between bacterial counts in P. magnifica and the surrounding water were observed. Fifty-four isolates were identified by sequencing the 16S rRNA gene and through MALDI-TOF MS analysis. Species of Aeromonas and Aquitalea were the predominantly isolated bacteria, but members of Chryseobacterium, Herbaspirillum, Enterobacter, Lactococcus, Leuconostoc, Pseudomonas and Sphingomonas were also found. As listed genera are wildly distributed in different water, soil, and plant samples, we conclude thatPectinatella colonies are inhabited by environmental bacteria. Nevertheless, a symbiotic relationship of these bacteria with P. magnifica cannot be excluded.