ERs span a wide range of sizes, from small plasmid-like elements to large replicons approaching chromosomal dimensions. If ER size is shaped by lineage-specific genomic constraints, ER size is expected to scale with chromosome size.
For each ER–chromosome pair, we extracted the absolute ER size (bp) and the relative size expressed as a percentage of the chromosome (100 × ER size / chromosome size). Analyses were performed on log-transformed values to assess scaling relationships.
Size scaling was quantified using Spearman rank correlations between log10 chromosome size and log10 ER size (absolute scaling), and between log10 chromosome size and log10 ER size as a percentage of the chromosome (relative scaling). Analyses were conducted globally and for phyla containing at least 100 ERs.
| label | n_pairs | rho_abs | p_abs | rho_rel | p_rel |
|---|---|---|---|---|---|
| GLOBAL | 54710 | 0.09970713244263377 | 6.923510966647698e-121 | -0.13081142665086884 | 2.3746865948656253e-207 |
| Phylum: Actinomycetota | 1824 | 0.25061283701573206 | 1.6049397864341047e-27 | -0.03241595060625714 | 0.1664058693100043 |
| Phylum: Bacillota | 10464 | 0.23829571844841677 | 5.049486698552399e-135 | 0.0290797280820828 | 0.0029303960136567533 |
| Phylum: Bacteroidota | 582 | -0.14949058504690854 | 0.000295727882969925 | -0.3422714150943811 | 1.9384847367468662e-17 |
| Phylum: Campylobacterota | 488 | 0.21332248015161984 | 1.9824398579425778e-06 | 0.13084012510358736 | 0.0037867954283388825 |
| Phylum: Cyanobacteriota | 486 | 0.306481503009211 | 4.985356073132775e-12 | 0.05222929244034898 | 0.25045885245424804 |
| Phylum: Deinococcota | 219 | 0.24863440367020778 | 0.00020165457478111838 | 0.07205870048060399 | 0.28839483249675135 |
| Phylum: Pseudomonadota | 38747 | -0.13011232437452494 | 6.9452497611010764e-146 | -0.24444787493101497 | 0.0 |
| Phylum: Spirochaetota | 1496 | 0.4274681814192872 | 1.6593935372593467e-67 | 0.024544256991176638 | 0.34278539237666317 |
Number of ER–chromosome pairs: 54710
Spearman ρ (absolute size) = 0.100 (p = 6.9e-121), indicating a very weak positive association.
Spearman ρ (relative size, %chr) = -0.131 (p = 2.4e-207), indicating a weak negative association.
Pairs: 1824
Spearman ρ (abs) = 0.251 (p = 1.6e-27), indicating a weak positive association.
Spearman ρ (%chr) = -0.032 (p = 0.1664), indicating a very weak negative association.
Pairs: 10464
Spearman ρ (abs) = 0.238 (p = 5.0e-135), indicating a weak positive association.
Spearman ρ (%chr) = 0.029 (p = 0.0029), indicating a very weak positive association.
Pairs: 582
Spearman ρ (abs) = -0.149 (p = 0.0003), indicating a weak negative association.
Spearman ρ (%chr) = -0.342 (p = 1.9e-17), indicating a strong negative association.
Pairs: 488
Spearman ρ (abs) = 0.213 (p = 2.0e-06), indicating a weak positive association.
Spearman ρ (%chr) = 0.131 (p = 0.0038), indicating a weak positive association.
Pairs: 486
Spearman ρ (abs) = 0.306 (p = 5.0e-12), indicating a strong positive association.
Spearman ρ (%chr) = 0.052 (p = 0.2505), indicating a very weak positive association.
Pairs: 219
Spearman ρ (abs) = 0.249 (p = 0.0002), indicating a weak positive association.
Spearman ρ (%chr) = 0.072 (p = 0.2884), indicating a very weak positive association.
Pairs: 38747
Spearman ρ (abs) = -0.130 (p = 6.9e-146), indicating a weak negative association.
Spearman ρ (%chr) = -0.244 (p = 0.0e+00), indicating a weak negative association.
Pairs: 1496
Spearman ρ (abs) = 0.427 (p = 1.7e-67), indicating a strong positive association.
Spearman ρ (%chr) = 0.025 (p = 0.3428), indicating a very weak positive association.