1 Supplementary Information 2 Supplementary Materials and Methods 3 Denaturing gradient gel electrophoresis (DGGE) analysis of gut microbiota 4 A. PCR amplification and DGGE 5 DNA isolated from each faecal sample was used as template in the amplification of the V3 6 region of the 16S rRNA gene using the universal bacterial primers P2 (5’- 7 ATTACCGCGGCTGCTGG-3’) and P3 (5’- 8 CGCCCGCCGCGCGCGGCGGGCGGGGCGGGGGCACGGGGGGCCTACGGGAGGCA 9 GCAG-3’) and the hot-start touchdown protocol described by Muyzer et al(Muyzer et al., 10 1993) in a thermocycler PCR system (PCR Sprint, Thermo electron, Corp., UK). Each 25 μl 11 PCR reaction mixture contained 1.5 U of rTaq DNA polymerase (Takara, Dalian, China), 2.5 12 μl of the corresponding 10× buffer (Takara, Dalian, China), 0.2 mmol/L each 13 deoxynucleoside triphosphate (dNTP), 25 pmol of each primer, and 20 ng of total faecal 14 DNA. After the initial amplification, a reconditioning PCR method was performed to 15 decrease heteroduplexes formation (Thompson et al., 2002). Parallel DGGE was performed 16 using a Dcode System apparatus (Bio-Rad) in an 8% (w/v) acrylamide gel with a gradient 17 from 27% to 52% and electrophoresis in 1× Tris-acetate-EDTA (TAE) buffer at the constant 18 voltage of 200 V and a temperature of 60oC for 240 minutes. After electrophoresis, the gels 19 were stained with SYBR GreenⅠ (Amresco, Solon, Ohio) and visualized on a UVI gel 20 documentation system (UVltec, Cambridge, United Kingdom). 21 B. Sequence analysis of DGGE bands 22 Important DGGE bands were excised from the original gel and incubated in 100 μl sterile 23 distilled water at 4°C overnight. A 1-μl aliquot of elution was used for PCR amplification of 24 the DNA fragments from the excised gel with corresponding primers, P2 and P3. PCR 25 products was excised from a 1.0% agarose gel and purified with a DNA Gel Extraction Kit 26 (V-gene, Hangzhou, China). The products were ligated into the pGEM-T easy vector 27 (Promega, Madison, WI) and transformed into competent E.coli DH5α cells (TIANGEN, 28 China). Inserted DNA was amplified using corresponding primers and resolved by DGGE to 29 verify the position of the original band. Then three clones migrating to the same position of 30 the original band were sequenced (Invitrogen, Shanghai, China). 31 The sequences of excised DGGE bands were submitted to the RDP database (version 9.33) 32 to determine their closest relatives with length greater than 1,200 nt. The sequences obtained 33 are available in the GenBank database under accession numbers EU584214-EU584231. 34 Terminal restriction fragment length polymorphism (T-RFLP) analysis of faecal 35 samples 36 A. 16S rRNA gene amplification and purification 37 DNA isolated from each faecal sample was used as template in the amplification of the 38 16S rRNA gene using the universal bacterial primers, 8F (5’- 39 GAGAGTTTGATCCTGGCTCAG-3’), 5’ end labelled with D4, and 1492R (5’- 40 GGC/TTACCTTGTTACGACTT-5’) (Hayashi et al., 2002). Each 25 μl PCR reaction 41 mixture contained 1.5 U of rTaq DNA polymerase (Takara, Dalian, China), 2.5 μl of the 42 corresponding 10× buffer (Takara, Dalian, China), 0.2 mmol/L each deoxynucleoside 43 triphosphate (dNTP), 25 pmol of each primer, and 10 ng of total faecal DNA. A 20 cycles 44 PCR program (Eckburg et al., 2005) was performed with a thermocycler PCR system (PCR 45 Sprint, Thermo electron, Corp., UK). Each 100 μl PCR product was digested by 1 U Mung 46 bean nuclease (Promega, Madison, WI) to remove the single stranded extensions. Digestion 47 products were purified with a DNA purification Kit (V-gene, Hangzhou, China), according to 48 the manufacturer’s instruction. 49 B. T-RFLP 50 A 50-ng sample of 16S rRNA gene amplification product from each mouse sample was 51 digested at 37°C for 3 h with 5 U of the following restriction endonucleases: AluⅠ, HaeⅢ, 52 HhaⅠ, MspⅠ, or Csp6Ⅰ(Promega, Madison, WI). The efficiency of restriction digestion 53 was confirmed by agarose gel electrophoresis, and the digested fragments were separated on 54 a CEQTM 8000 genetic analysis system (Beckman Coulter). The sizes of the fluorescently 55 labelled fragments were determined by comparison with the internal size standard 56 (GenomeLabTM DNA Size Standard 600 Kit, Beckman Coulter). Fluorescence intensity data 57 were automatically collected and subsequently analyzed by the fragment analysis software 58 provided with the CEQTM 8000 system. Relative peak areas of each TRF were determined 59 by dividing the area of the peak of interest by the total area of peaks within the following 60 threshold values: a lower threshold at 60 nt and an upper threshold at 640 nt. A threshold for 61 relative peak area was applied at 3%, and only TRFs with higher relative abundances were 62 included in the remaining analyses. The two peaks were identified as the same if the 63 difference of the peak size was less than 1 nt. T-RFLP was repeated three times from each 64 16S rRNA gene amplification. 65 C. Statistical analysis of T-RFLP data 66 In the matrix used for statistical analysis, the data of three replicates from each animal 67 were as independent objects and the relative peak height of TRFs from every restriction 68 endonuclease was as the variable. This matrix was used for PCA. 69 variance (MANOVA) is a generalized form of analysis of variance (ANOVA) methods to 70 cover cases where there is more than one (correlated) dependent variable and where the 71 dependent variables cannot simply be combined, and the number of variables should less 72 than the number of samples. Because the TFRs far outnumber our animals and PC1 to PC9 73 from PCA, which accounts for 98% of total variations, PC1 to PC9 were used for 74 Multivariate ANOVA test. The clusters are computed by applying the single linkage method 75 to the matrix of Mahalanobis distances between group means. H returns a vector of handles 76 to the lines in the figure. All the above methods were implemented in Matlab® (ver. 7.1, 77 The MathWorks, Inc.). 78 Pyrosequencing of 16S rRNA gene V3 region 79 A. PCR amplification of 16S rRNA gene V3 region 80 Multivariate analysis of For faecal samples from each mouse, the extracted DNA was used as template in the 81 amplification of the V3 region of 16S rRNA gene. The forward primer was 5’- 82 NNNNNNNNCCTACGGGAGGCAGCAG-3’, and the reverse primer was5’- 83 NNNNNNNNATTACCGCGGCTGCT-3’, where the underlined sequence is the universal 84 bacterial primer P1 and P2. The NNNNNNNN is the unique eight base barcode used to 85 distinguish PCR product from different samples. Reaction conditions were as follows: Each 86 25 μl PCR reaction mixture contained 0.25 U of Platinum® Pfx DNA polymerase 87 (Invitrogen, USA), 2.5 μl of the corresponding 10× Pfx amplification buffer (Invitrogen, 88 USA), 0.5 mM of MgSO4 (Invitrogen, USA), 0.3 mmol/L each deoxynucleoside triphosphate 89 (dNTP), and 6.25 pmol of each primer, and 20 ng of total faecal DNA. PCR reactions were 90 run in a thermocycler PCR system (PCR Sprint, Thermo electron, Corp., UK) using the 91 following program: 3 minutes denaturing at 94°C followed by 20 cycles of 1 minute at 94°C 92 (denaturing), 1 minute for annealing (1°C reduced for every 2 cycles from 65°C to 57°C 93 followed by 1 cycle at 56°C and 1 cycle at 55°C), and 1 minute at 72°C (elongation), with a 94 final extension at 72°C for 6 minutes. Three independent PCR reactions using different 95 barcoded primers were performed for two animals from each group. 96 B. Gel purification and pyrosequencing 97 Each PCR product was isolated with the Gel/PCR DNA Fragments Extraction Kit 98 (Geneaid, UKAS). 30 ng of each purified PCR product was mixed, and the mixture was 99 purified from 1.2% agarose gel with the Gel/PCR DNA Fragments Extraction Kit (Geneaid, 100 UKAS) and used as the DNA library for pyrosequencing using a GS20 platform (Roche), as 101 described previously (Margulies et al., 2005). Based on several previous reports describing 102 sources of errors in 454 sequencing runs (Margulies et al., 2005; Sogin et al., 2006; 103 McKenna et al., 2008), standards were used for quality control, as follows: if a sequence (a) 104 shows no mismatch to the barcode and 16S rRNA gene primer at sequencing end, (b) is more 105 than 100 nt in length, (c) has no more than two undermined bases in the sequence read, and 106 (d) finds more than 75% mach to a previously determined 16S rRNA gene sequence, then it 107 will be regarded as usable. The unique sequences obtained in this study are available in the 108 GenBank database under accession numbers FJ032696- FJ036862. 109 C. Bioinformatic and Statistical analysis 110 The unique V3 sequences of 16S rRNA gene from pyrosequencing were aligned using 111 NAST multi-aligner with a minimum template length of 100 bases and a minimum percent 112 identity of 75% (DeSantis et al., 2006). The resulting alignments were imported into the 113 ARB (Ludwig et al., 2004) for construction of a neighbour-joining tree. The phylogenetic 114 tree was then used for online UniFrac (http://bmf.colourado.edu/unifrac ) with abundance 115 weighting (incorporating abundance data). 116 A distance matrix of unique sequences from ARB was imported into DOTUR for 117 phylotype binning (Schloss and Handelsman, 2005). The abundance information of each 118 unique sequence was added to the OTU results from DOTUR, and measured for coverage 119 (rarefaction analysis with software Past) and diversity (Shannon index with R software 120 (http://www.r-project.org/)). 121 OTUs were defined using a threshold of 97% identity, which was a criterion for species 122 level delineation in previous studies (Huse et al., 2007). One sequence randomly selected 123 from each OTU was BLAST searched against the RDP database (version 9.33) to identify the 124 taxonomic group and inserted into pre-established phylogenetic trees of full length 16S 125 rRNA gene sequences database from GreenGenes using ARB (hypervariable regions masked 126 with the lanemaskPH filter) (Ludwig et al., 2004). 127 Errors in pyrosequencing may occur at a rate of about 0.25%, suggesting that most of the 128 200 nt sequences will contain either 0 or 1 error. Using the Poisson model, we would expect 129 only 1.029e-6 of the reads to contain the six errors that would be required to form a new 130 species-level at the 97% OTU identity. Thus, it is unlikely that a single OTU in analysis was 131 generated through that mechanism. 132 133 PLS-DA was used to test if two groups can be separated based on OTUs data. Martens’ uncertainty test was used to select significant OTUs which can discriminate the different 134 treatment groups (different diets, host genotypes, or cages). One-way ANOVA was further 135 performed to validate these differential variables. All statements of significance are at P< 136 0.05. The correct prediction rate of the PLS-DA model was performed with leave-one-out 137 CV. 138 Quantitative Real-time PCR of Bifidobacterium spp. 139 The plasmid containing the 16S rRNA gene of Bifidobacterium spp. was prepared with 3S 140 Spin plasmid Miniprep Kit V3.1 (Shanghai Biocolour BioScience & Technology Company) 141 and linearized with ScalⅠlinear. The plasmid was then diluted from 2.39E+9 to 2.39E+2 142 (copies/μl) to make a standard curve. Real-time PCR amplification and detection were 143 performed in the DNA Engine Opticon 2 system (MJ Research). The primers were the 144 Bifidobacterium specific primers: Bif164-f (5’-GGGTGGTAATGCCGGATG-3’) and 145 Bif662-r (5’-CCACCGTTACACCGGGAA-3’) (Satokari et al., 2001). The reaction mixture 146 (25 μl) was composed of 1.5 U rTaq DNA polymerase (Takara, Dalian, China), 12.5μl of 147 2×SYBR greenⅠmix (Shanghai Biocolour BioScience & Technology Company), 25 pmol of 148 each primer, and 20 ng of total faecal DNA from each mouse or 1μl stander plasmid. The 149 amplification program was as follows: one cycle of 94°C for 5 min, then 40 cycles of 94°C 150 for 30 s, 62°C for 20 s, and 72°C for 40 s, and finally one cycle of 88°C for 10 s. The 151 fluorescent product was detected at the last step of each cycle. Following amplification, 152 melting temperature analysis of PCR products was performed to determine the specificity of 153 the PCR. The melting curves were obtained by slow heating at 0.5°C/s increments from 70 154 to 95°C, with continuous fluorescence collection. Each sample had three replicates of 155 quantitative analysis. The data detected by the system was analyzed using Opticon Monitor 156 (Version 1.1). 157 Supplementary Results 158 T-RFLP analysis of gut microbiota 159 In the PCA based on T-RFLP data, the variables influenced PCs 1, 2, and 3 are shown in 160 Figure S8. 161 Pyrosequencing of 16S rRNA gene V3 region 162 A total of 29,343 high quality sequences of pyrosequencing were first selected based on 163 the following criteria: if a sequence (a) shows no mismatch to the barcode and 16S rRNA 164 gene primer at sequencing end, (b) is more than 100 nt in length, (c) has no more than two 165 undermined bases in the sequence read. All the sequences were aligned using NAST multi- 166 aligner with a minimum template length of 100 bases and a minimum percent identity of 167 75% (DeSantis et al., 2006). In all, 29 sequences had no neighbours with higher than 75% 168 homology and were discarded. A total of 29,314 useable sequence reads were then obtained. 169 There were 4,156 unique sequences in all the samples, 3,145 of which were detected only 170 once. Because two animals from each treatment group had three replicates, we used 36 171 different barcodes. All barcodes were well populated, with an average of 814 sequences per 172 sample tested and only two samples had less than 500 reads (Table S 3). 173 UniFrac provides a suite of tools for the comparison of microbial communities using 174 phylogenetic information. The UniFrac analysis based on the unique sequences of all the 175 four treatment groups revealed the significant impact of diet on gut microbiota (Fig.S2a), but 176 the difference between mice having different genotypes was not obvious. These results 177 confirmed that diets have a more significant influence on gut microbiota than genotypes. 178 Hierarchical Clustering Analysis based on UniFrac analysis also indicated that the three 179 replicates of the same animal were more similar to each other than to another animal 180 (Fig.S2b). In other words, this 454 barcoded technology shows satisfactory reproducibility. 181 In order to do phylotype binning and diversity estimation of our pyrosequencing data, the 182 ARB distance matrix of sequence reads were imported to DOTUR. When sequences were 183 condensed under 99% identity, 1,360 different operational taxonomic units (OTUs) were 184 obtained. But the number of OTUs was reduced to 516 under 97% identity (Fig.S1a). The 185 rarefaction analysis and Shannon Diversity Index were calculated for each of the 20 mice 186 (Fig.S1b and 1c). For all the samples, the rarefaction curves did not reach a stable value, 187 indicating that the actual numbers of OTUs in the samples are larger, echoing some recent 188 reports based on pyrosequencing that the diversity of community of macaque gut or deep sea 189 has been underestimated (McKenna et al., 2008)(Sogin et al., 2006). The curves of Shannon 190 Diversity Index of all the samples had reached stable values. There was no significant 191 difference of Shannon Diversity Index among the four groups. 192 Analysis of the taxa present in the mice gut communities indicated that bacteria of 193 Firmicutes and Bacteroidetes were dominant, which was followed by Actinobacteria and 194 Proteobacteria. Phylum-wide changes associated with IGT/Obesity were not observed. 195 More than 20 different families were found in the 20 mouse faecal samples, showing 196 significant difference with the family level composition of gut bacteria in human (Ley et al., 197 2005). The relative abundance distribution of families showed individual-specific difference 198 among the 20 mice (Fig.S5). The proportion of Erysipelotrichaceae was the highest in most 199 mice. 200 PLS-DA was used to find patterns out of this complex dataset. Using 97% identity to 201 define OTUs, a PLS-DA scores plot with the first two components showed that animals with 202 different diets, genotypes, or health phenotypes were separated into different classes 203 (Fig.S3). The PLS-DA model of Apoa-Ⅰ-/- mice fed on different diets yielded a 99% correct 204 classification rate in leave-one-out cross validation when 2 PLS components were used. The 205 correct classification rate of wildtype mice fed different diets, animals with different 206 genotypes fed HFD, and animals with different genotypes fed NC are as follows: 99% using 207 1 PLS component, 80% using 2 PLS components, 90% using 2 PLS components. When the 208 mice were divided into two groups based on the diet, the correct classification rate was 90% 209 with 1 PLS component. When the mice were divided into two groups based on genotype, the 210 correct classification rate was 75% with 2 PLS components. When the mice were divided 211 into two groups based on health status, the correct classification rate was 95% with 2 PLS 212 components. 213 Sixty-five OTUs were selected using Martens’ uncertainty test key variables for the 214 classifications. One random sequence from each of the key OTUs was inserted into the pre- 215 established phylogenetic tree (Fig.S4). 21 OTUs (pink marked in the tree) increased in the 216 mice group fed on HFD compared with their counterparts fed on NC, but 26 OTUs (blue) 217 showed opposite behaviour. We also found 4 OTUs (yellow) with genotype-dependent 218 reactions. For example, one phylotype, OTU 64 in Class Clostridia, was high in the Apoa-Ⅰ 219 -/- 220 S1). However, it disappeared completely in HFD groups regardless of genotype, confirming 221 the results with DNA fingerprinting that high fat diet can diminish genotype-related 222 differences. There was 1 OTU (purple) increased in the knockout mice, which may be only 223 associated with genotype. There were 12 OTUs (green) reduced and 1 OTU (orange) 224 abundant in mice with IGT. Four lineages were found in Class Erysipelotrichi, M1 (9 OTUs), 225 M2 (6 OTUs), M3 (14 OTUs), M4 (1 OTU). M1 were abundant in healthy Wt/NC animals, 226 but significantly reduced in the other three groups with IGT. M2 and M4 were predominant 227 in HFD/obese groups and M3 had much higher population levels in NC/lean animals. 228 /NC group but low in Wt/NC animals, showing a response to genotype difference (Table When one sequence randomly selected from each OTU under 97% identity was BLAST 229 searched against the RDP database (version 9.33) to identify the taxonomic group and 230 inserted into pre-established phylogenetic trees of full length 16S rRNA gene sequences 231 using ARB, more OTUs were found in the four lineages in Class Erysipelotrichi. The total 232 OTUs in the four lineages M1-4 were 36, 30, 44, and 4, respectively. Those OTUs which 233 were not selected as key variables for separating classes were mostly rare phylotypes. 234 However, most rare phylotypes showed similar behaviour to the identified ones in the same 235 lineage (Fig.S6). 236 Real time PCR of Bifidobacterium 237 Standard curve showed the linear relationship between the threshold cycles and the log 238 quantity of the input standard plasmid (R2=0.999). Based on the standard curve, the average 239 copy number of three replicates for each sample was calculated (Fig.S7). The 240 Bifidobacterium spp. were present in all wildtype and most knockout mice on NC but 241 disappeared in all HFD animals regardless of genotype. 242 243 Supplementary References 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 DeSantis, T.Z., Jr., Hugenholtz, P., Keller, K., Brodie, E.L., Larsen, N., Piceno, Y.M. et al. (2006) NAST: a multiple sequence alignment server for comparative analysis of 16S rRNA genes. Nucleic Acids Res 34: W394-399. Eckburg, P.B., Bik, E.M., Bernstein, C.N., Purdom, E., Dethlefsen, L., Sargent, M. et al. (2005) Diversity of the human intestinal microbial flora. Science 308: 1635-1638. Hayashi, H., Sakamoto, M., and Benno, Y. (2002) Phylogenetic analysis of the human gut microbiota using 16S rDNA clone libraries and strictly anaerobic culture-based methods. Microbiol Immunol 46: 535-548. Huse, S.M., Huber, J.A., Morrison, H.G., Sogin, M.L., and Welch, D.M. (2007) Accuracy and quality of massively parallel DNA pyrosequencing. Genome Biol 8: R143. Ley, R.E., Backhed, F., Turnbaugh, P., Lozupone, C.A., Knight, R.D., and Gordon, J.I. (2005) Obesity alters gut microbial ecology. Proc Natl Acad Sci U S A 102: 11070-11075. Ludwig, W., Strunk, O., Westram, R., Richter, L., Meier, H., Yadhukumar et al. (2004) ARB: a software environment for sequence data. Nucleic Acids Res 32: 1363-1371. Margulies, M., Egholm, M., Altman, W.E., Attiya, S., Bader, J.S., Bemben, L.A. et al. (2005) Genome sequencing in microfabricated high-density picolitre reactors. Nature 437: 376-380. McKenna, P., Hoffmann, C., Minkah, N., Aye, P.P., Lackner, A., Liu, Z. et al. (2008) The macaque gut microbiome in health, lentiviral infection, and chronic enterocolitis. PLoS Pathog 4: e20. Muyzer, G., de Waal, E.C., and Uitterlinden, A.G. (1993) Profiling of complex microbial populations by denaturing gradient gel electrophoresis analysis of polymerase chain reactionamplified genes coding for 16S rRNA. Appl Environ Microbiol 59: 695-700. Satokari, R.M., Vaughan, E.E., Akkermans, A.D., Saarela, M., and de Vos, W.M. (2001) Bifidobacterial diversity in human feces detected by genus-specific PCR and denaturing gradient gel electrophoresis. Appl Environ Microbiol 67: 504-513. Schloss, P.D., and Handelsman, J. (2005) Introducing DOTUR, a computer program for defining operational taxonomic units and estimating species richness. Appl Environ Microbiol 71: 1501-1506. Sogin, M.L., Morrison, H.G., Huber, J.A., Mark Welch, D., Huse, S.M., Neal, P.R. et al. (2006) Microbial diversity in the deep sea and the underexplored "rare biosphere". Proc Natl Acad Sci U S A 103: 12115-12120. 275 276 277 278 279 280 281 282 283 284 Thompson, J.R., Marcelino, L.A., and Polz, M.F. (2002) Heteroduplexes in mixed-template amplifications: formation, consequence and elimination by 'reconditioning PCR'. Nucleic Acids Res 30: 2083-2088. Wang, Y., Holmes, E., Nicholson, J.K., Cloarec, O., Chollet, J., Tanner, M. et al. (2004) Metabonomic investigations in mice infected with Schistosoma mansoni: an approach for biomarker identification. Proc Natl Acad Sci U S A 101: 12676-12681. 285 the collection of pyrosequencing reads was analyzed by condensing sequences at several 286 percent identity thresholds. The X-axis shows the percent identity, the Y-axis the number of 287 OTUs detected. (b) Rarefaction analysis of sampling. Repeated samples of OTU subsets 288 were used to evaluate where further sampling would likely yield additional taxa, as indicated 289 by whether the curve has reached a plateau value. (c) Shannon Diversity Index curves to 290 estimate the diversity of taxa present in individual animals. Color code for each treatment 291 group in this figures: green=Wt/NC; yellow=Wt/HFD; blue= Apoa-Ⅰ-/-/NC; red= Apoa-Ⅰ-/- 292 /HFD. Supplementary Figure Legends Figure S1. Diversity of the mouse gut microbiota. (a) The numbers of OTUs present in 293 294 Figure S2. Comparison of gut microbiota among groups of mice based on 295 pyrosequencing data and Unifrac metrics. The phylogenetic tree of all unique sequences 296 in four groups was used for UniFrac analysis. (a) The PCoA plot was generated using 297 weighted UniFrac. (b) Hierarchical clustering analysis based on weighted UniFrac. Each 298 point represents an individual samples (two animals from each treatment group had three 299 replicates). Color code for each treatment group in this figures: green=Wt/NC; 300 black=Wt/HFD; blue= Apoa-Ⅰ-/-/NC; red=Apoa-Ⅰ-/-/HFD. 301 302 Figure S3. PLS-DA scores plots of first two components based on pyrosequencing OTU 303 (97%) data. (a) A PLS-DA scores plot of Apoa-Ⅰ-/- mice given different diets. (b) A PLS- 304 DA scores plot of wild-type mice given different diets. (c) A PLS-DA scores plot of Apoa- 305 Ⅰ-/- and wild-type mice given HFD. (d) A PLS-DA scores plot of Apoa-Ⅰ-/- and wild-type 306 mice given NC. (e) A PLS-DA scores plot of all the mice with the distinction of diet. (f) A 307 PLS-DA scores plot of all the mice with the distinction of genotype. (g) A PLS-DA scores 308 plot of all the mice with the distinction of IGT phenotype. Animal groups are color-coded as 309 in Figure S2. 310 311 Figure S4. Phylogeny of OTUs under 97% identity showing significant differences 312 among four treatment groups of mice. 65 OTUs were selected using PLS-DA and 313 Martens’ uncertainty test. One random sequence of each of these OTUs was inserted into the 314 phylogenetic tree of full-length 16S rRNA gene sequences from the GreenGenes database. 315 The sequences of important DGGE bands were also inserted into the tree. The color codes 316 are as follows: pink=increased in high fat diet; blue=increased in normal chow; green, 317 reduced in mice with IGT; orange=abundant in mice with IGT; yellow=genotype-dependent 318 reaction to diet; purple=increased in Apoa-Ⅰ-/- mice. 319 320 Figure S5. Summary of the bacterial taxa present in the gut community of each mouse. 321 Each sample analyzed is indicated along the X-axis, the Y-axis indicates the relative 322 abundance of each type (family) of bacteria present in that gut community. A key to the 323 bacteria taxa is listed at the right. 324 325 Figure S6. Comparison of abundance distribution OTUs and rare phylotypes in M1 - 326 M4. (a) Abundance distribution of dominant OTUs in M1-M4, which were selected by as 327 key variables for separating classes. (b) Abundance distribution of rare phylotypes in M1- 328 M4, which were not selected as key variables for separating classes. 329 330 Figure S7. Real-time PCR analysis of Bifidobacterium. Every sample had three 331 replicates of RT-PCR, and the histogram shows the average copy numbers of 332 Bifidobacterium spp. in every ng of faecal DNA from each mouse. Mean values ± SEM are 333 shown. 334 335 Figure S8. Coefficient of variables on PCs 1, 2, and 3 of T-RFLP data PCA analysis. 336 The absolute value of coefficient of marked variable is more than 0.1. (a) Coefficient of 337 variables on PC1. (b) Coefficient of variables on PC2. (c) Coefficient of variables on PC3. Figure S1 Figure S2 Figure S3 Figure S4 Figure S5 Figure S6 Figure S7 Figure S8 Table S1 OTUs (97% identity) showing significant differences among the treatment groups of mice. Closest Relatives (Identified sequences using RDP database) Abundance distribution (%) One-way ANOVA P value(s) ApoaⅠ-/- High Wild-type High ApoaⅠ-/- ApoaⅠ-/- fat diet fat diet High fat diet Normal chow Representative OTU sequence ApoaⅠ-/- ApoaⅠ-/- Wild-type Wild-type High fat Normal High fat Normal diet chow diet chow Healthy High Fat Diet Knockout Similarity ACC No. Phylum Class Order Family VS. VS. VS. VS. ApoaⅠ-/- Wild-type Wild-type Wild-type Normal chow Normal chow High fat diet Normal chow VS. VS. VS. (%) Unhealthy Normal chow Wild-type 7 U000028382 EF096080 Proteobacteria Deltaproteobacteria Desulfovibrionales Desulfovibrionaceae 100 2.03 2.13 4.68 0.75 / 0.0075 / / / / / 9 U000023613 EU504743 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 99.4 0 3.94 0.81 1.25 0.0093 / / / / / / 38 U000003735 EU009776 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 94.3 0 0.53 0 1.16 / 0.032 / / / 0.0039 / 40 U000006061 EU009776 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 93 0 0.39 0 1.11 / 0.045 / / / 0.0081 / 11 U000016351 EU504815 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 99.4 1.93 1.1 3.77 0.67 / 0.000019 / / / 0.0073 / 180 U000025698 EF614639 Bacteroidetes Bacteroidetes Bacteroidales 98.1 0.016 0.024 0 0.1 / / / / 0.0035 / / 67 U000039702 AY850513 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 89.1 0.46 0.44 0.014 0.1 / / / / / / 0.0077 46 U000001832 EF406868 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 100 0.37 0 1.99 0 / 0.039 / / / 0.0032 / 100 U000040596 EF097551 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 95.6 0.016 0.14 0 0.17 / 0.013 / / / / / 81 U000016500 EF604763 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 99.4 0.13 0.071 0.029 0.4 / / / / 0.011 / / 75 U000041621 DQ015203 Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae 98.8 0.065 0.22 0.072 0.4 / 0.0077 / / 0.0017 0.0025 / 62 U000031422 EF097211 Bacteroidetes Bacteroidetes Bacteroidales Rikenellaceae 98.1 0.11 0.51 0.37 0.052 / / / 0.019 / / / 27 U000020286 AY174109 Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae 98.7 0 0 0 3.5 / 0.000011 / / / / / 15 U000024557 AY174109 Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae 98.1 0 1.88 0 3.5 / 0.0031 / / / 0.0016 / 8 U000031489 AY174109 Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae 100 0 2.39 0.014 6.3 / 0.00032 / / / 0.0064 / 183 U000003389 D86185 Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae 96.1 0 0.094 0. 0.077 / / / / / 0.041 / 36 U000001115 EU503611 Actinobacteria Actinobacteria Coriobacteriales Coriobacteriaceae 100 0.39 0.38 0.97 0.83 / / / / / / 0.03 52 U000014392 DQ071473 Actinobacteria Actinobacteria Coriobacteriales Coriobacteriaceae 95.9 0.6 0 0 0.65 0.017 / / / / / / 43 U000000324 DQ014810 Firmicutes Clostridia Clostridiales Lachnospiraceae 99.3 0 1.57 0 0.052 / / / 0.017 / 0.023 / 91 U000033955 EF097536 Firmicutes Clostridia Clostridiales Lachnospiraceae 97.8 0.42 0 0.1 0 / 0.013 / / / 0.011 / 161 U000033147 DQ015450 Firmicutes Clostridia Clostridiales Lachnospiraceae 100 0 0.059 0 0.065 / 0.025 / / / 0.0073 / 108 U000005416 EU508080 Firmicutes Clostridia Clostridiales Lachnospiraceae 92.8 0.16 0.012 0.27 0.013 / / / / / 0.014 / 64 U000009711 EU507738 Firmicutes Clostridia Clostridiales Lachnospiraceae 99.3 0 0.12 0.79 0.065 / 0.0032 / / / / / 18 U000029595 EU506836 Firmicutes Clostridia Clostridiales Lachnospiraceae 99.1 1.54 0.32 3.31 0.19 / / / / / 0.016 / 89 U000010964 EU508875 Firmicutes Clostridia Clostridiales Ruminococcaceae 99.3 0.081 0 0.33 0 / / / / / 0.015 / 72 U000009642 EF603323 Firmicutes Clostridia Clostridiales Ruminococcaceae 99.3 0.16 0.059 0.63 0.077 / 0.0015 0.007 / / 0.0065 / 58 U000025890 EU509242 Firmicutes Clostridia Clostridiales Ruminococcaceae 99.3 0.29 0.51 0.79 0.09 / 0.0067 / / / / / 59 U000000934 EU509809 Firmicutes Clostridia Clostridiales Ruminococcaceae 99.3 0.33 0.15 0.6 0.052 / 0.0051 / / / 0.0055 / 39 U000017048 DQ815552 Firmicutes Clostridia Clostridiales Ruminococcaceae 99 1.32 0.024 0.58 0 / / / / / 0.01 / 34 U000012845 EF603866 Firmicutes Clostridia Clostridiales Lachnospiraceae 99.3 0.55 0.21 1.18 0.065 / 0.012 / / 0.013 / 33 U000000486 DQ808568 Firmicutes Clostridia Clostridiales Ruminococcaceae 99.3 1.93 0.024 0.89 0 / / / / / 0.0027 / 87 U000002211 DQ325814 Firmicutes Clostridia Clostridiales Lachnospiraceae 100 0.46 0.047 0.37 0.052 / / / / / 0.025 / 74 U000008559 EF096608 Firmicutes Clostridia Clostridiales Lachnospiraceae 99.3 0.39 0.21 0.95 0.065 / / / / / 0.015 / 24 U000030860 EU507383 Firmicutes Clostridia Clostridiales Lachnospiraceae 99.4 1.2 0.46 1.05 0.15 / 0.000089 / / 0.00069 0.00022 / 28 U000030555 AY328550 Firmicutes Bacilli Lactobacillales Streptococcaceae 100 1.19 0.54 1.11 0.14 / 0.012 / / 0.013 0.0018 / 77 U000037248 EU510844 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.8 0.081 0.035 0 0.86 / 0.0022 / 0.0029 0.00016 / / 145 U000027359 EU508960 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 96.4 0 0 0 0.14 / 0.033 / 0.033 0.00017 / / 357 U000029900 EU505653 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 94.6 0 0 0 0.065 / / / / 0.0013 / / 88 U000018234 EU507232 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0.033 0.012 0.014 0.86 / 0.00026 / 0.00015 0.00016 / / 212 U000034857 EU511304 Firmicutes 99.4 0 0.012 0 0.1 / 0.048 / / 0.0011 / / 141 U000002839 EU507232 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.8 0.016 0 0.014 0.3 / 0.032 / 0.029 0.0017 / / 6 U000034579 EU505377 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0.88 0.24 0.37 12.5 / 0.00049 / 0.00035 0.00016 / / 56 U000006185 EU508960 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 96.9 0.13 0.035 0.043 1.85 / 0.0024 / 0.0015 0.00016 / / 217 U000037797 EU511394 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0 0 0 0.34 / 0.0021 / 0.0021 0.00016 / / 2 U000035271 EU505669 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 24.3 0.083 3.86 0.93 0.0021 0.046 0.037 / / 0.00082 / 131 U000008904 EU503568 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0.88 0.035 0.14 0.013 0.02 / / / / 0.0082 / 26 U000008160 EU505483 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 2.8 0.024 0.32 0.026 0.014 0.045 / / / 0.0069 / 5 U000010299 EU503724 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.8 13.9 0.17 2.87 0.3 0.0021 / / / / 0.00046 / 359 U000022068 EU503645 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0.098 0 0.014 0 / / / / / 0.029 / 101 U000021437 EU503645 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0.37 0 0.014 0.026 0.0016 / 0.0026 / / 0.019 / 86 U000035671 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.8 0.016 0.31 0 0.46 / 0.00049 / / / 0.0044 / 127 U000037422 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.2 0.016 0.059 0 0.15 / 0.0029 / / / 0.034 / 21 U000024281 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 97.6 0.098 1.88 0.029 1.85 / 0.00036 / / / 0.0014 / 227 U000026824 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 100 0 0.15 0 0.077 / / / / / 0.027 / 134 U000001902 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0 0.2 0 0.18 / / / / / 0.012 / 208 U000035866 EU511581 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 93.9 0 0 0 0.065 / 0.013 / / / / / 214 U000035767 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 0 0.11 0 0.12 / / / / / 0.0033 / 185 U000036828 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.2 0 0.083 0 0.1 / / / / / 0.0097 / 102 U000038832 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 97.5 0 0.19 0 0.24 / 0.0025 / / / 0.00037 / 1 U000029463 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.8 0.91 29.6 0.37 30.2 0.023 0.000022 / / / 0.00019 / 116 U000038624 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 98.8 0 0.4 0 0.34 / 0.0049 / / / 0.019 / 160 U000029891 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 96.2 0 0.19 0 0.28 / 0.002 / / / 0.00037 / 219 U000026363 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99 0.016 0.059 0 0.026 / / / / / 0.013 / 201 U000034887 EF603858 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 96.9 0 0.083 0 0.18 / 0.011 / / / 0.0015 / 35 U000018452 EU507348 Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae 99.4 1.5 0.024 0.66 0.13 / / / / / 0.00096 / 22 Table S2 Sequence analysis of the significant different V3 DGGE bands between groups. Band No. Closest molecular relatives and isolates identified from RDP database Organism (Similarity) Phylum Class Order Family Clostridium cocleatum Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae AF028350 (100%) 1 Clostridium cocleatum(T) Y18188 (99.5%) Uncultured bacterium EU503645 (100%) 2 Allobaculum stercoricanis (T) AJ417075 (85.6%) Uncultured bacterium EU503646 (100%) 3 Allobaculum stercoricanis (T) AJ417075 (85.6%) Uncultured bacterium EU503571 (100%) 4 Allobaculum stercoricanis (T) AJ417075 (85.6%) Uncultured bacterium 6a EF603858 (99.5%) Allobaculum stercoricanis (T) 23 AJ417075 (92.3%) Uncultured bacterium Bacteroidetes Bacteroidetes Bacteroidales Porphyromonadaceae Bacteroidetes Flavobacteria Flavobacteriales Flavobacteriaceae Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae Actinobacteria Actinobacteria Bifidobacteriales Bifidobacteriaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae Firmicutes Erysipelotrichi Erysipelotrichales Erysipelotrichaceae EU504743 (99.5%) 6b cf.Bergeyella sp.CCUG 46293 (T) AJ575430 (81.5%) Bifidobacterium pseudolongum subsp. pseudolongum AY174109 (98.9%) 10 Bifidobacterium animalis subsp. animalis (T) AY722379 (98.9%) Bifidobacterium animalis subsp. animalis D86185 (97.9%) 11 Bifidobacterium animalis subsp. animalis (T) AY722379 (97.8%) Uncultured bacterium EU507135 (100%) 12 Allobaculum stercoricanis (T) AJ417075 (87.6%) 24 Table S3 Pyrosequencing reads of all samples. Total Unique Group NO. Total Unique Group NO. reads sequence 1 reads sequence 577 165 1 510 119 2a 595 171 2 335 93 2b 524 154 3a 640 204 2c 469 152 3b 1419 315 3c 607 178 ApoaⅠ-/- Wildtype 3 886 242 High fat diet High fat diet 4 629 160 4 861 245 5a 706 174 5a 1167 341 5b 879 174 5b 762 239 5c 887 182 5c 642 221 1a 944 224 1a 711 229 1b 1080 286 1b 842 248 1c 921 249 1c 779 213 2 1006 278 2 864 280 3 207 3 925 237 ApoaⅠ-/- Wildtype 750 Normal chow Normal chow 4a 927 227 4 964 270 4b 865 223 5a 922 220 4c 978 256 5b 947 218 5 255 5c 796 198 998