Table 3.
Diversity data and indices computed from 454-pyrosequencing data of gut bacterial communities in mice on diets supplemented with different Fe sources for 28 days
| Group | Number of sequences | Richness (S) | Shannon diversity index (H′)1 | Shannon evenness index (EH)1 | Good's coverage (ESC %)1 |
|---|---|---|---|---|---|
| Effect of Fe-depletion | |||||
| @ weaning (day 0), n = 23 | 3889 (746) | 35 (4)x | 2.4 (0.2)x | 0.67 (0.06) | 92 (2) |
| After Fe-depletion (day 28), n = 17 | 3592 (893) | 27 (4)y | 2.1 (0.2)y | 0.63 (0.06) | 93 (2) |
| Fe-sufficient (reference, day 28), n = 5 | 3439 (611) | 37 (4)x | 2.4 (0.2)x | 0.66 (0.05) | 91 (2) |
| Effect of Fe-repletion | |||||
| Fe-sufficient (reference) n = 5 | |||||
| Day 28, n = 5 | 3439 (611) | 37 (4) | 2.4 (0.2) | 0.66 (0.05) | 91 (2) |
| Day 42, n = 5 | 3519 (1166) | 34 (2) | 2.3 (0.2) | 0.66 (0.04) | 91 (2) |
| Day 56, n = 5 | 2613 (446)x | 43 (10) | 2.6 (0.2)x | 0.70 (0.04)x | 87 (2)x |
| Fe-deficient (FD) | |||||
| Day 28, n = 5 | 3284 (717)a | 25 (3)a | 2.0 (0.2) | 0.63 (0.06) | 92 (3) |
| Day 42, n = 6 | 4057 (730)a | 31 (3)b | 1.8 (0.4) | 0.51 (0.09) | 94 (1) |
| Day 56, n = 6 | 6506 (1494)b,y | 33 (3)b | 1.7 (0.3)y | 0.47 (0.09)y | 95 (2)y |
| FeSO4 | |||||
| Day 28, n = 4 | 3734 (443) | 29 (4) | 2.1 (0.2) | 0.61 (0.05) | 94 (2) |
| Day 42, n = 4 | 3853 (309) | 25 (4) | 2.0 (0.1) | 0.64 (0.02) | 93.7 (0.5) |
| Day 56, n = 4 | 3407 (1505)xz | 32 (3) | 2.1 (0.2)z | 0.62 (0.05)x | 89 (4)x |
| Nano Fe(III) | |||||
| Day 28, n = 8 | 3767 (1116) | 28 (4) | 2.1 (0.3)a | 0.64 (0.08)a | 93 (3) |
| Day 42, n = 8 | 5036 (1460) | 31 (7) | 2.0 (0.3)a | 0.59 (0.06)a | 94 (1) |
| Day 56, n = 7 | 4777 (911)yz | 32 (9) | 1.6 (0.1)b,y | 0.47 (0.04)b,y | 94 (1)y |
Mice underwent an initial period of 28 days of dietary-induced Fe-depletion (i.e., weaning to study day 28), followed by 28 days of Fe-repletion (i.e., study day 28 to study day 56) with the Fe-deficient diet supplemented with FeSO4 or nano Fe(III) as per study outline in Figure1B. Data for the control Fe-deficient group (i.e., the group that remained on the Fe-deficient diet throughout) and the Fe-sufficient reference group (i.e., iron-replete mice) are also shown. Values are mean (SD). OTU, operational taxonomic unit; ESC, estimated sample coverage; d, day; FeSO4, ferrous sulfate; Nano Fe(III), nanoparticulate tartrate-modified ferrihydrite.
, and 
; where S, is the total number of unique OTUs within each sample; n1, is the number of single copy OTU within each sample; N, is the total number of sequences, and pi, is the proportional abundance of each unique OTU within each sample (Hariri et al. 1990; Godden and Bajorath 2000; Claesson et al. 2010).
a,bWhere statistical significance was established, means in a column within each group without a common superscripts letter differ: within-group comparisons (i.e., comparing the different timepoints for each diet group) were performed using one-way repeated-measures ANOVA, with the Greenhouse–Geisser correction for nonsphericity and the Tukey's multiple comparisons test with pairwise exclusion of missing data. P < 0.05 was considered significant (multiplicity adjusted).
x,y,zBetween-group comparisons (i.e., comparing the different diet groups) at the end of the study (day 56) or comparing the effect of Fe-depletion (day 0 versus day 28) was carried out with ordinary one-way ANOVA with the Tukey's multiple comparison test: where statistical significance was established, means without a common superscripts letter differ. P < 0.05 was considered significant (multiplicity adjusted).