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With the Munster cheese (Fig. (Fig.3B,3B, lane 2), we detected five bands; three bands, a, b, and c, were respectively assigned to Kluyvera cryocrescens, Streptococcus thermophilus, and the Arthrobacter sulfureus group; two bands, d and e, were assigned to Brevibacterium linens. However, we did not confirm the presence of Brevibacterium linens in the Munster cheese with specific primers designed by S. Furlan et al. (unpublished data) (Table (Table44).With Morbier cheese, the DGGE method revealed 9 bands. The species database allowed us to identify six of them (Fig. (Fig.3B,3B, lane 3) as corresponding to Lactobacillus buchneri (band a), Streptococcus thermophilus (band b), Lactobacillus reuteri-Enterobacter sakazakii (band d), Lactobacillus casei (band f), the Micrococcus luteus group (band h), and Brevibacterium linens (band i). The presence of Brevibacterium linens in the Morbier cheese was confirmed by specific PCR testing (Table (Table4).4). However, a very faint band (not visible on the gel photograph) was assigned to E. coli.
Three of the unassigned bands were cloned and sequenced; sequence
comparison against the GenBank database allowed us to identify them as Corynebacterium variabile (band c), Arthrobacter species (band e), and Corynebacterium casei (band g). We also identified the Corynebacterium mastitidis species bacteria by sequencing a clone originating from band h (Fig. (Fig.3B,3B, lane 3). Each new species fingerprint was added to the database after validation with pure strains.We detected seven bands in the DGGE pattern of the Epoisses cheese (Fig. (Fig.3B,3B, lane 1); four bands were assigned to Kluyvera cryocrescens (band b), Buttiauxella agrestis-Enterobacter intermedius (band c), Brevibacterium linens (band d), and the Arthrobacter sulfureus group (band g). The presence of Brevibacterium linens was confirmed by a specific PCR test (Table (Table4).4). Sequencing of the unassigned bands a and f (Fig. (Fig.3B,3B, lane 1) revealed the presence of Pseudoalteromonas and Halomonas, although the habitat of these two genera is generally salt water (57). We did not succeed in sequencing the unknown band e (Fig. (Fig.3B,3B, lane 1).
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