This sample was used consistently in DGGE gels as PF-6463922 Marker to normalize the gels and to allow for gel-to-gel comparisons using BioNumerics. A BLAST comparison showed
that the sequences from these bands were similar to Acinetobacter sp. and Lactobacillus sp. (Table 3). Figure 4 Results from RISA analysis. A low percentage of DNA similarity was found between the DNA profiles from subsamples M and the DNA profiles from subsamples A. Table 3 Results from BLAST analysis of sequenced DGGE bands. Marker Band ID BLAST nearest homology (GenBank accession number) % Identity A K 1 Acinetobacter sp. (FN563421) 96 B K 2 Uncultured Myxococcales bacterium (FJ435015) 93 C K 3 Lactobacillus sp. L21 (AF159000) 87 D K 4 Lactobacillus sp. (FJ971864) 95 E K 5 Lactobacillus sp. JN4 (AF157041) 90 Microaerobic subsamplea Campylobacter jejuni (GQ479820) 98 Lactobacillus sp. 30A (FJ971864) 98 Pseudomonas sp. CB10 (EU482914) learn more 98 Pseudomonas sp. R-35702 (AM886093) 97 Aerobic subsamplea Campylobacter jejuni CB-5083 mw (GQ479820) 98 Lactobacillus sp. JN4 (AF157041) 83 Pseudomonas sp. CB11 (EU482915) 98 Uncultured bacterium clone FF_e08 (EU469596) Marker bands were used in all the gels. a Unique DGGE bands from each subsample. O2 content decreased during the incubation of enrichment broths In samples incubated in Bolton broth without the addition of any microaerobic gas mix, the amount of O2 in the head
space Thalidomide of the bags decreased over time and was at or below
17% at 24 h of incubation. The amount of O2 in the atmosphere was stable between 14 and 16% by 30 h of incubation; however, the amount of O2 never reached less than 14% (Figure 5). The amount of dissolved O2 in the enrichment broth, measured one inch from the bottom of the enrichment bags, reached 6 ppm at around 6 h of incubation. This value was stable thereafter and never reached above 7.5 ppm (Figure 6). The presence of naturally occurring Campylobacter spp., either C. jejuni or C. coli, did not alter any of the values obtained with the sensors. In addition, incubation of 100 ml of Bolton broth without meat samples and without the addition of blood resulted in a similar pattern of DO values. In samples in which the O2 sensors were double bagged and gassed with a microaerobic gas mix, the DO decreased to around 5 ppm and remained stable for up to 72 h (data not shown). Identical patterns of dissolved O2 levels were found when using ziplock plastic bags commonly used to freeze food products (The Glad Products Company, Oakland, CA) (data not shown). Figure 5 Oxygen measurements. Percentage of O2 in the head space of plastic bags throughout 48 h of incubation at 42°C. Average ± SEM of six measurements from subsamples positive for Campylobacter spp. after incubation under aerobic conditions. Measures were taken with an O2 sensor (Vernier, Beaverton, OR) as the percentage of O2 in the air in the head space. Figure 6 Oxygen measurements.