title: Comparative quantification of human intestinal bacteria based on cPCR and LDR/LCR.
abstract: OBJECTIVE
  To establish a multiple detection method based on comparative polymerase chain reaction (cPCR) and ligase detection reaction (LDR)/ligase chain reaction (LCR) to quantify the intestinal bacterial components.
  
  
  METHODS
  Comparative quantification of 16S rDNAs from different intestinal bacterial components was used to quantify multiple intestinal bacteria. The 16S rDNAs of different bacteria were amplified simultaneously by cPCR. The LDR/LCR was examined to actualize the genotyping and quantification. Two beneficial (Bifidobacterium, Lactobacillus) and three conditionally pathogenic bacteria (Enterococcus, Enterobacterium and Eubacterium) were used in this detection. With cloned standard bacterial 16S rDNAs, standard curves were prepared to validate the quantitative relations between the ratio of original concentrations of two templates and the ratio of the fluorescence signals of their final ligation products. The internal controls were added to monitor the whole detection flow. The quantity ratio between two bacteria was tested.
  
  
  RESULTS
  cPCR and LDR revealed obvious linear correlations with standard DNAs, but cPCR and LCR did not. In the sample test, the distributions of the quantity ratio between each two bacterial species were obtained. There were significant differences among these distributions in the total samples. But these distributions of quantity ratio of each two bacteria remained stable among groups divided by age or sex.
  
  
  CONCLUSIONS
  The detection method in this study can be used to conduct multiple intestinal bacteria genotyping and quantification, and to monitor the human intestinal health status as well.
authors.affiliation: College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China.
authors.forename: Zhou-Rui
authors.initials: ZR
authors.lastname: Tang
authors.forename: Kai
authors.initials: K
authors.lastname: Li
authors.forename: Yu-Xun
authors.initials: YX
authors.lastname: Zhou
authors.forename: Zhen-Xian
authors.initials: ZX
authors.lastname: Xiao
authors.forename: Jun-Hua
authors.initials: JH
authors.lastname: Xiao
authors.forename: Rui
authors.initials: R
authors.lastname: Huang
authors.forename: Guo-Hao
authors.initials: GH
authors.lastname: Gu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000235:genetics*; D005243:Feces / Q000382:microbiology; D005838:Genotype; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D022521:Ligase Chain Reaction / Q000379:methods*; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D016133:Polymerase Chain Reaction / Q000379:methods*; D012336:RNA, Ribosomal, 16S / Q000032:analysis / Q000235:genetics; D055815:Young Adult
chemical_list: D012336:RNA, Ribosomal, 16S