Table 1.
Histidine Variants in the Companion Amino Acids Variants Dictionary
| CODE | Variant |
|---|---|
| HIS | HISTIDINE |
| HIS_LEO2 | L-HISTIDINE C-TERMINAL DEPROTONATED FRAGMENT |
| HIS_LEO2H | L-HISTIDINE C-TERMINAL PROTONATED FRAGMENT |
| HIS_LEO2H_DHD1 | L-HISTIDINE-C-TERMINAL PROTONATED FRAGMENT/WITH SIDE CHAIN DEPROTONATED ND1 |
| HIS_LEO2H_DHE2 | L-HISTIDINE-C-TERMINAL PROTONATED FRAGMENT/WITH SIDE CHAIN DEPROTONATED NE2 |
| HIS_LEO2_DHD1 | L-HISTIDINE-C-TERMINAL DEPROTONATED FRAGMENT/WITH SIDE CHAIN DEPROTONATED ND1 |
| HIS_LEO2_DHE2 | L-HISTIDINE-C-TERMINAL DEPROTONATED FRAGMENT/WITH SIDE CHAIN DEPROTONATED NE2 |
| HIS_LFOH | L-HISTIDINE FREE NEUTRAL |
| HIS_LFOH_DHD1 | L-HISTIDINE-FREE NEUTRAL/WITH SIDE CHAIN DEPROTONATED ND1 |
| HIS_LFOH_DHE2 | L-HISTIDINE-FREE NEUTRAL/WITH SIDE CHAIN DEPROTONATED NE2 |
| HIS_LFZW | L-HISTIDINE FREE ZWITTERION |
| HIS_LFZW_DHD1 | L-HISTIDINE-FREE ZWITTERION/WITH SIDE CHAIN DEPROTONATED ND1 |
| HIS_LFZW_DHE2 | L-HISTIDINE-FREE ZWITTERION/WITH SIDE CHAIN DEPROTONATED NE2 |
| HIS_LL | L-HISTIDINE - LINKING EMBEDDED FRAGMENT |
| HIS_LL_DHD1 | L-HISTIDINE-LINKING EMBEDDED FRAGMENT/WITH SIDE CHAIN DEPROTONATED ND1 |
| HIS_LL_DHE2 | L-HISTIDINE-LINKING EMBEDDED FRAGMENT/WITH SIDE CHAIN DEPROTONATED NE2 |
| HIS_LSN3 | L-HISTIDINE N-TERMINAL PROTONATED FRAGMENT |
| HIS_LSN3_DHD1 | L-HISTIDINE-N-TERMINAL PROTONATED FRAGMENT/WITH SIDE CHAIN DEPROTONATED ND1 |
| HIS_LSN3_DHE2 | L-HISTIDINE-N-TERMINAL PROTONATED FRAGMENT/WITH SIDE CHAIN DEPROTONATED NE2 |
Note: The Chemical Component Dictionary is accompanied by a companion dictionary of amino acid variants that provides additional nomenclature information for the protonation states of standard amino acids in N-terminal, C-terminal and free forms. This dictionary also includes common side chain protonation states. It is similar to residue variants used in modeling software such as Charmm (42) and Amber (43).