DNAs of magnetically purified cells from eight bottles
were obtained by boiling the cells in 200 lL water at
100 C for 15 min and then centrifuged. Primers used for
16S rRNA gene amplification were 341F-GC (50-CC TAC
GGG AGG CAG CAG-30) to which a 40 bp GC-clamp was
added at the 50 end and 907R (50-CCG TCA ATT CMT
TTG AGT TT-30) [17]. The 50 lL PCR reaction mix
contained 10 lL Taq-& LOADTM Mastermix 5xC (MP
Biomedicals Europe), 0.5 lL of each primer at 25 lM,
37 lL of sterile water, and 2 lL of extracted DNA as
template. PCR reactions were performed in the T100TM
Thermal Cycler (BIO-RAD). The cycling conditions were
5 min at 94 C for initial denaturation; 35 cycles of 1 min
at 94 C, 1 min at 55 C, and 1 min at 72 C; and a final
extension of 5 min at 72 C