Carious dentine provides a habitat for a complex array of novel Prevotella-like bacteria.
Previous analysis of the microbiology of advanced caries by culture and real-time PCR emphasized the high incidence and abundance of gram-negative anaerobic species, particularly Prevotella-like bacteria. The diversity of Prevotella-like bacteria was further explored by analyzing pooled bacterial DNA from lesions of carious dentine. This was achieved by amplification of a region of the 16S ribosomal DNA with a Prevotella genus-specific forward primer and a universal bacterial reverse primer, followed by cloning and sequencing. Cultured Prevotella species commonly associated with oral tissues constituted only 12% of the Prevotella clones isolated from advanced carious lesions. The remaining 88% consisted of a diverse range of phylotypes. These included five clusters of previously recognized but uncultured oral Prevotella spp. and a major cluster containing Prevotella-like bacteria most closely related to uncharacterized rumen bacteria. Cluster-specific primers were designed, and the numbers of bacteria within clusters were quantified by real-time PCR, confirming the abundance of these organisms. The data indicated that advanced dental caries provides a unique environment for a complex array of novel and uncultured Prevotella and Prevotella-like bacteria which, in some cases, may dominate the diverse polymicrobial community associated with the disease.
Nadkarni
Mangala A
MA
Institute of Dental Research, Westmead Millenium Institute, Wentworthville, New South Wales, Australia. mnadkarni@dental.wsahs.nsw.gov.au
Caldon
C Elizabeth
CE
Chhour
Kim-Ly
KL
Fisher
Ilana P
IP
Martin
F Elizabeth
FE
Jacques
Nicholas A
NA
Hunter
Neil
N
D000293:Adolescent; D000328:Adult; D000368:Aged; D016866:Bacteroidaceae Infections / Q000382:microbiology*; D017931:DNA Primers; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D003731:Dental Caries / Q000382:microbiology*; D003804:Dentin / Q000382:microbiology*; D017753:Ecosystem; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D018720:Prevotella / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
D017931:DNA Primers; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S