Table 2. Associations of alpha diversity measures and of major bacterial taxa and selected genera with levels of microbial enzymatic activity.
| β-glucuronidasea | β-glucosidasea | |||
| Betab | P-value | Betab | P-value | |
| Alpha diversity measures | ||||
| Chao1 | 0.008 | 0.04 | 0.005 | 0.04 |
| Shannon | 0.661 | 0.02 | 0.414 | 0.02 |
| Observed species | 0.014 | 0.01 | 0.009 | 0.007 |
| Phylogenetic distance (PD) whole tree | 0.249 | 0.002 | 0.155 | 0.001 |
| Beta diversity measures c | ||||
| Principal component 1 | −2.54 | 0.029 | −1.75 | 0.012 |
| Principal component 2 | −3.53 | 0.003 | −2.5 | 0.0005 |
| Major phyla, selected genera (mean relative abundance) | ||||
| Firmicutes (80.3%) | 0.002 | 0.932 | −0.003 | 0.91 |
| Firmicutes Lactobacillales | ||||
| Streptococcaceae Streptococcus (0.5%) | −0.2 | 0.04 | −0.41 | 0.008 |
| Firmicutes Clostridia | ||||
| non-Clostridiales (0.2%) | 0.32 | 0.0001d | 0.42 | 0.005 |
| Firmicutes Clostridia Clostridiales | ||||
| Lachnospiraceae Roseburia (4.0%) | −0.26 | 0.02 | −0.58 | 0.0001d |
| Peptostreptococcaceae genus NA (0.2%) | 0.1 | 0.32 | 0.35 | 0.03 |
| Ruminococcaceae Oscillibacter (1.2%) | 0.24 | 0.01 | 0.19 | 0.23 |
| Ruminococcaceae Subdoligranulum (2.8%) | 0.28 | 0.002 | 0.53 | 0.0001 |
| Ruminococcaceae genus NA (4.4%) | 0.15 | 0.04 | 0.23 | 0.05 |
| Bacteroidetes (16.9%) | −0.005 | 0.77 | −0.0009 | 0.98 |
| Bacteroidetes Bacteroidales | ||||
| Rikenellaceae Alistipes (0.6%) | 0.3 | 0.003 | 0.56 | 0.0001d |
| Actinobacteria (1.3%) | 0.002 | 0.27 | 0.002 | 0.55 |
| Proteobacteria (0.5%) | −0.0002 | 0.78 | −0.0002 | 0.84 |
| Fusobacteria (0.2%) | −0.02 | 0.73 | −0.06 | 0.49 |
| Unclassified bacteria (0.8%) | 0.09 | 0.32 | 0.28 | 0.055 |
Log values of enzymatic activity IU/100 mg fecal protein. the two significantly associated principal components, per unit increase in alpha diversity, per tertile for Firmicutes and Bacteroidetes phyla, and per level (none, low, high) for the minor phyla, genera and unclassified bacteria.
Beta values estimate the increase (or decrease for negative values) in loge of enzymatic activity for the two significantly associated principal components, per unit increase in alpha diversity, per tertile for Firmicutes and Bacteroidetes phyla, and per level (none, low, high) for the minor phyla, genera and unclassified bacteria.
Principal component analysis based on unweighted Unifrac, adjusted for sex and age.
Statistically significant at P<0.05 with Bonferroni correction for 61 taxa with mean relative abundance ≥0.1% that were evaluated.