Ine 2. However, these differences exceeded the threshold of statistical significance in only a few cases. Differences in Shannon andDNA Extraction from Salivary buy Lecirelin MicrobiotaTable 1. Number of sequence reads, number of OTUs, and ecological indices in enzymatically- and mechanically-processed samples using different bioinformatic analysis pipelines.Pipeline # of reads after the first quality filter # of reads after chimera removal # of reads after chimera removal in M # of reads after chimera removal in E Average of reads identified as chimeras Average of reads identified as chimeras in M Average of reads identified as chimeras in E # of reads normalized to (per sample) # total of OTUs AVG # of OTUs in M AVG # of OTUs in E AVG Chao 1 in M AVD Chao 1 in E of OTUs shared among M of OTUs shared among E of OTUs shared between M and E Average Spearmans’s rho among M based on OUT abundance/P value* Average Spearmans’s rho among E based on OUT abundance/P value* Average Spearmans’s rho between E and M based on OTU abundance/P value* Average Spearmans’s rho between E and M based on OTU prevalence/P value* Shannon diversity index [H'(loge)] in M Shannon diversity index [H'(loge)] in E Simpson diversity index [1-l] in M Simpson diversity index [1-l] in E1/5 80,288 76,767 38,038 38,729 4.062.2 2.660.8 5.462.2 (P = 0.041) 43,524 (3,627) 480 214618 195619 313630 281643 71.764.4 70.565.5 67.265.6 0.670/ P,2 80,288 78,697 38,679 40,018 1.861.4 0.960.3 2.661.5 44,340 (3,695) 630 227620 218634 357647 366672 6964.5 65.567.8 6466.4 0.663/ P,3 80,288 74,182 36,761 37,421 7.262.3 5.860.8 8.662.5 41,988 (3,499) 356 17768 167612 255624 251627 74.262.8 7264.1 (P = 0.026) 69.164 0.693/ P,4 80,288 76,767 38,038 38,729 4.062.2 2.660.8 5.462.2 (P = 0.041) 43,524 (3,627) 352 163613 146615 227625 200639 75.564.6 73.466 70.666.3 0.718/ P,6 134,928 123,508 61,639 61,869 8.062.3 6.860.8 9.262.8 69,552 (5,796) 326 21069 18466 (P = 0.005) 250618 219615 (P = 0.041) 83.263.6 8362.6 79.866.1 0.814/ P,10262 0.824/ P,10271 0.722/ P,10241 0.750/P,10266 3.6060.08 3.5460.09 0.93460.010 0.93460.0.685/ P,10257 0.605/ P,10237 0.629/ P,10253 3.3560.15 3.4560.15 0.89360.020 0.90860.0.631/ P,10255 0.692/ P,10241 (P = 0.029) 0.587/ P,10241 0.529/P,10245 3.4160.17 3.5260.18 0.89560.022 0.91160.013 0.601/ P,10225 0.656/P,10244 3.2360.13 3.3060.13 0.88660.019 0.90160.0.710/ P,10241 0.639/ P,10233 0.649/P,10242 3.0860.16 3.1160.15 0.87460.022 0.89760.E, enzymatic lysis; M, mechanical lysis. When a significant difference (Mann-Whitney U test P,0.05) was found between mechanical and enzymatic lysis, the corresponding values are given in bold and P value is indicated in parentheses. *The highest P value for any pairwise comparison. doi:10.1371/journal.pone.0067699.tSimpson diversity indices between the extraction methods were not statistically significant (Table 1).DiscussionThe current study showed that the same bacterial taxa tended to be abundant and frequent in human saliva samples processed by either the mechanical or enzymatic lysis methods, but that their relative abundance, determined by pyrosequencing of 16S rDNA amplicon Title Loaded From File libraries, differed between the 23977191 extraction methods. These differences could be distinguished with as few as 100 sequences per sample, i.e. far below the number of reads routinely analyzed in community studies based on HTS of 16S rDNA amplicon libraries. Similarly, Kuczynski et al. [35] showed that ,100 sequences per sample were sufficient to discriminate bet.Ine 2. However, these differences exceeded the threshold of statistical significance in only a few cases. Differences in Shannon andDNA Extraction from Salivary MicrobiotaTable 1. Number of sequence reads, number of OTUs, and ecological indices in enzymatically- and mechanically-processed samples using different bioinformatic analysis pipelines.Pipeline # of reads after the first quality filter # of reads after chimera removal # of reads after chimera removal in M # of reads after chimera removal in E Average of reads identified as chimeras Average of reads identified as chimeras in M Average of reads identified as chimeras in E # of reads normalized to (per sample) # total of OTUs AVG # of OTUs in M AVG # of OTUs in E AVG Chao 1 in M AVD Chao 1 in E of OTUs shared among M of OTUs shared among E of OTUs shared between M and E Average Spearmans’s rho among M based on OUT abundance/P value* Average Spearmans’s rho among E based on OUT abundance/P value* Average Spearmans’s rho between E and M based on OTU abundance/P value* Average Spearmans’s rho between E and M based on OTU prevalence/P value* Shannon diversity index [H'(loge)] in M Shannon diversity index [H'(loge)] in E Simpson diversity index [1-l] in M Simpson diversity index [1-l] in E1/5 80,288 76,767 38,038 38,729 4.062.2 2.660.8 5.462.2 (P = 0.041) 43,524 (3,627) 480 214618 195619 313630 281643 71.764.4 70.565.5 67.265.6 0.670/ P,2 80,288 78,697 38,679 40,018 1.861.4 0.960.3 2.661.5 44,340 (3,695) 630 227620 218634 357647 366672 6964.5 65.567.8 6466.4 0.663/ P,3 80,288 74,182 36,761 37,421 7.262.3 5.860.8 8.662.5 41,988 (3,499) 356 17768 167612 255624 251627 74.262.8 7264.1 (P = 0.026) 69.164 0.693/ P,4 80,288 76,767 38,038 38,729 4.062.2 2.660.8 5.462.2 (P = 0.041) 43,524 (3,627) 352 163613 146615 227625 200639 75.564.6 73.466 70.666.3 0.718/ P,6 134,928 123,508 61,639 61,869 8.062.3 6.860.8 9.262.8 69,552 (5,796) 326 21069 18466 (P = 0.005) 250618 219615 (P = 0.041) 83.263.6 8362.6 79.866.1 0.814/ P,10262 0.824/ P,10271 0.722/ P,10241 0.750/P,10266 3.6060.08 3.5460.09 0.93460.010 0.93460.0.685/ P,10257 0.605/ P,10237 0.629/ P,10253 3.3560.15 3.4560.15 0.89360.020 0.90860.0.631/ P,10255 0.692/ P,10241 (P = 0.029) 0.587/ P,10241 0.529/P,10245 3.4160.17 3.5260.18 0.89560.022 0.91160.013 0.601/ P,10225 0.656/P,10244 3.2360.13 3.3060.13 0.88660.019 0.90160.0.710/ P,10241 0.639/ P,10233 0.649/P,10242 3.0860.16 3.1160.15 0.87460.022 0.89760.E, enzymatic lysis; M, mechanical lysis. When a significant difference (Mann-Whitney U test P,0.05) was found between mechanical and enzymatic lysis, the corresponding values are given in bold and P value is indicated in parentheses. *The highest P value for any pairwise comparison. doi:10.1371/journal.pone.0067699.tSimpson diversity indices between the extraction methods were not statistically significant (Table 1).DiscussionThe current study showed that the same bacterial taxa tended to be abundant and frequent in human saliva samples processed by either the mechanical or enzymatic lysis methods, but that their relative abundance, determined by pyrosequencing of 16S rDNA amplicon libraries, differed between the 23977191 extraction methods. These differences could be distinguished with as few as 100 sequences per sample, i.e. far below the number of reads routinely analyzed in community studies based on HTS of 16S rDNA amplicon libraries. Similarly, Kuczynski et al. [35] showed that ,100 sequences per sample were sufficient to discriminate bet.
