Table 4. The most common ternary anion–π–cation surface interactions in proteins. Triads of interacting residues and their occurrences in number (amount), percentage (%), and residues' representativities for each distinct anion (%A–), central π-system (%πc), and cation (%C+). The expected amount of each interaction pair, according to its relative abundance, and the statistical significance are shown (Methods). Statistical significance is denoted with * for p-value < 0.05.
| Interaction | Amount (expected) | % | %A– | %πc | %C+ |
| Glu–Phe–Arg | 47 (46) | 17.8 | 31.3 | 41.2 | 25.0 |
| Asp–Phe–Arg | 43 (35) | 16.3 | 37.7 | 37.7 | 22.9 |
| Asp–Tyr–Arg | 21 (18) | 8.0 | 18.4 | 35.6 | 11.2 |
| Glu–His–Arg | 21 (17) | 8.0 | 14.0 | 48.8 | 11.2 |
| Glu–Trp–Lys | 20 (8)* | 7.6 | 13.3 | 41.7 | 26.3 |
| Glu–Trp–Arg | 20 (19) | 7.6 | 13.3 | 41.7 | 10.6 |
| Glu–Tyr–Arg | 19 (24) | 7.2 | 12.7 | 32.2 | 10.1 |
| Asp–Phe–Lys | 14 (14) | 5.3 | 12.3 | 12.3 | 18.4 |
| Asp–His–Arg | 10 (13) | 3.8 | 8.8 | 23.3 | 5.3 |
| Glu–Phe–Lys | 10 (19) | 3.8 | 6.7 | 8.8 | 13.2 |