SEQ2FUN

BioLiP
Download all results in tab-seperated text for 1072681 receptor-ligand interactions, whose format is explained at readme.txt.
  • Hover over PDB to view the title of the structure. Click PDB to view the structure at the RCSB PDB database. Resolution -1.00 means the resolution is unavailable, e.g., for NMR structures.
  • Click Site # to view the binding site structure. Hover over Site # to view the binding residues.
  • Hover over Ligand to view the full ligand name. Click Ligand to view the 2D diagram and other detail information of the ligand.
  • Hover over EC number to view the full name of enzymatic activity.
  • Hover over GO terms to view all GO terms.
  • Hover over UniProt to view the protein name.
  • Sort results by
    << < 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 > >>
    Go to page

    # PDB
    (Resolution Å)
    Site # Ligand EC number GO terms UniProt PubMed Binding
    affinity
    227601 4guo:B (3.19) BS01 dna ? GO:0000976 ... O15350 N/A
    227602 4guo:B (3.19) BS02 dna ? GO:0000976 ... O15350 N/A
    227603 4guo:B (3.19) BS03 ZN ? GO:0000976 ... O15350 N/A
    227604 4guo:C (3.19) BS01 dna ? GO:0000976 ... O15350 N/A
    227605 4guo:C (3.19) BS02 ZN ? GO:0000976 ... O15350 N/A
    227606 4guo:D (3.19) BS01 dna ? GO:0000976 ... O15350 N/A
    227607 4guo:D (3.19) BS02 ZN ? GO:0000976 ... O15350 N/A
    227608 4guo:I (3.19) BS01 dna ? GO:0000976 ... O15350 N/A
    227609 4guo:I (3.19) BS02 ZN ? GO:0000976 ... O15350 N/A
    227610 4guo:J (3.19) BS01 dna ? GO:0000976 ... O15350 N/A
    227611 4guo:J (3.19) BS02 ZN ? GO:0000976 ... O15350 N/A
    227612 4guo:K (3.19) BS01 dna ? GO:0000976 ... O15350 N/A
    227613 4guo:K (3.19) BS02 dna ? GO:0000976 ... O15350 N/A
    227614 4guo:K (3.19) BS03 ZN ? GO:0000976 ... O15350 N/A
    227615 4guo:L (3.19) BS01 dna ? GO:0000976 ... O15350 N/A
    227616 4guo:L (3.19) BS02 ZN ? GO:0000976 ... O15350 N/A
    227617 4gup:A (3.2) BS01 6FP ? N/A Q95460 23051753
    227618 4gup:C (3.2) BS01 6FP ? N/A Q95460 23051753
    227619 4guq:A (3.7) BS01 dna ? GO:0000976 ... O15350 23892287
    227620 4guq:A (3.7) BS02 dna ? GO:0000976 ... O15350 23892287
    227621 4guq:A (3.7) BS03 ZN ? GO:0000976 ... O15350 23892287
    227622 4guq:B (3.7) BS01 dna ? GO:0000976 ... O15350 23892287
    227623 4guq:B (3.7) BS02 ZN ? GO:0000976 ... O15350 23892287
    227624 4gur:A (2.506) BS01 peptide 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227625 4gur:A (2.506) BS02 peptide 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227626 4gur:A (2.506) BS03 FAD 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227627 4gur:A (2.506) BS04 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227628 4gur:A (2.506) BS05 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227629 4gur:A (2.506) BS06 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227630 4gus:A (2.23) BS01 peptide 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227631 4gus:A (2.23) BS02 peptide 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227632 4gus:A (2.23) BS03 FAD 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227633 4gus:A (2.23) BS04 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227634 4gus:A (2.23) BS05 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227635 4gus:A (2.23) BS06 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227636 4gut:A (1.998) BS01 peptide 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227637 4gut:A (1.998) BS02 FAD 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227638 4gut:A (1.998) BS03 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227639 4gut:A (1.998) BS04 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227640 4gut:A (1.998) BS05 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227641 4guu:A (2.302) BS01 peptide 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227642 4guu:A (2.302) BS02 FA9 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227643 4guu:A (2.302) BS03 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227644 4guu:A (2.302) BS04 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227645 4guu:A (2.302) BS05 ZN 1.14.99.66 GO:0000786 ... Q8NB78 23260659
    227646 4guv:A (2.73) BS01 FAD 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227647 4guv:A (2.73) BS02 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227648 4guv:A (2.73) BS03 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227649 4guv:B (2.73) BS01 FAD 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227650 4guv:B (2.73) BS02 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227651 4guv:B (2.73) BS03 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227652 4guv:C (2.73) BS01 FAD 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227653 4guv:C (2.73) BS02 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227654 4guv:C (2.73) BS03 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227655 4guv:D (2.73) BS01 FAD 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227656 4guv:D (2.73) BS02 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227657 4guv:D (2.73) BS03 XE 1.14.13.231 GO:0000166 ... Q93L51 23999299
    227658 4guw:A (1.6) BS01 LP5 3.2.2.22 GO:0017148 ... D9J2T9 N/A
    227659 4gux:A (1.803) BS01 CA 3.4.21.4 GO:0004252 ... P00760 24169696
    227660 4gux:B (1.803) BS01 CA 3.4.21.4 GO:0004252 ... P00760 24169696
    227661 4gux:C (1.803) BS01 CA 3.4.21.4 GO:0004252 ... P00760 24169696
    227662 4guy:A (2.0) BS01 ZN 3.4.24.65 GO:0004222 ... P39900 N/A
    227663 4guy:A (2.0) BS02 ZN 3.4.24.65 GO:0004222 ... P39900 N/A
    227664 4guy:A (2.0) BS03 CA 3.4.24.65 GO:0004222 ... P39900 N/A
    227665 4guy:A (2.0) BS04 CA 3.4.24.65 GO:0004222 ... P39900 N/A
    227666 4guy:A (2.0) BS05 CA 3.4.24.65 GO:0004222 ... P39900 N/A
    227667 4guy:A (2.0) BS06 KLJ 3.4.24.65 GO:0004222 ... P39900 N/A BindingDB: Ki=10.0nM
    227668 4gv0:A (1.9) BS01 8ME 2.4.2.- GO:0003950 ... Q9Y6F1 23742272 MOAD: ic50=1.3uM
    227669 4gv1:A (1.49) BS01 0XZ 2.7.11.1 GO:0004672 ... P31749 23394218 MOAD: ic50=3nM
    BindingDB: IC50=4.2nM
    227670 4gv2:A (1.8) BS01 5ME 2.4.2.- GO:0003950 ... Q9Y6F1 23742272
    227671 4gv3:A (1.68) BS01 rna 3.1.13.- N/A P13699 23615902
    227672 4gv3:A (1.68) BS02 rna 3.1.13.- N/A P13699 23615902
    227673 4gv3:A (1.68) BS03 ZN 3.1.13.- N/A P13699 23615902
    227674 4gv4:A (1.8) BS01 MEJ 2.4.2.- GO:0003950 ... Q9Y6F1 23742272 MOAD: ic50=0.89uM
    227675 4gv6:A (1.98) BS01 rna 3.1.13.- N/A P13699 23615902
    227676 4gv6:A (1.98) BS02 rna 3.1.13.- N/A P13699 23615902
    227677 4gv6:A (1.98) BS03 ZN 3.1.13.- N/A P13699 23615902
    227678 4gv7:A (2.89) BS01 MEW 2.4.2.-
    2.4.2.30
    GO:0003950 ... P09874 23742272 BindingDB: IC50=5600nM
    227679 4gv7:B (2.89) BS01 MEW 2.4.2.-
    2.4.2.30
    GO:0003950 ... P09874 23742272 BindingDB: IC50=5600nM
    227680 4gv7:C (2.89) BS01 MEW 2.4.2.-
    2.4.2.30
    GO:0003950 ... P09874 23742272 BindingDB: IC50=5600nM
    227681 4gv7:D (2.89) BS01 MEW 2.4.2.-
    2.4.2.30
    GO:0003950 ... P09874 23742272 BindingDB: IC50=5600nM
    227682 4gv8:A (2.1) BS01 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227683 4gv8:A (2.1) BS02 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227684 4gv8:B (2.1) BS01 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227685 4gv8:B (2.1) BS02 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227686 4gv8:C (2.1) BS01 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227687 4gv8:C (2.1) BS02 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227688 4gv8:D (2.1) BS01 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227689 4gv8:D (2.1) BS02 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227690 4gv8:E (2.1) BS01 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227691 4gv8:E (2.1) BS02 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227692 4gv8:F (2.1) BS01 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227693 4gv8:F (2.1) BS02 DUP 3.6.1.23 GO:0000287 ... Q8SDV3 24311572 MOAD: Kd=0.32uM
    227694 4gv9:A (2.46) BS01 rna 3.1.13.- N/A P13699 23615902
    227695 4gv9:A (2.46) BS02 rna 3.1.13.- N/A P13699 23615902
    227696 4gv9:A (2.46) BS03 MN 3.1.13.- N/A P13699 23615902
    227697 4gv9:A (2.46) BS04 ZN 3.1.13.- N/A P13699 23615902
    227698 4gva:A (1.83) BS01 ADP 2.7.11.24 GO:0000165 ... P63086 N/A
    227699 4gvc:A (1.54) BS01 peptide ? GO:0005085 ... Q13009 23395182
    227700 4gvd:A (1.85) BS01 peptide ? GO:0005085 ... Q13009 23395182
    227701 4gvd:A (1.85) BS02 peptide ? GO:0005085 ... Q13009 23395182
    227702 4gvd:B (1.85) BS01 peptide ? GO:0005085 ... Q13009 23395182
    227703 4gve:A (1.73) BS01 ZN 3.1.13.- N/A P18140 23615902
    227704 4gve:A (1.73) BS02 MG 3.1.13.- N/A P18140 23615902
    227705 4gvh:A (1.45) BS01 0XY 3.2.1.52 GO:0004553 ... Q8ZQ06 23177201
    227706 4gvh:B (1.45) BS01 0XY 3.2.1.52 GO:0004553 ... Q8ZQ06 23177201
    227707 4gvi:B (1.55) BS01 AH0 3.2.1.52 GO:0004553 ... Q8ZQ06 23177201
    227708 4gvj:A (2.03) BS01 ADP 2.7.10.2 GO:0004672 ... P29597 23867602
    227709 4gvj:A (2.03) BS02 MG 2.7.10.2 GO:0004672 ... P29597 23867602
    227710 4gvl:A (3.0) BS01 ZN ? GO:0006813 ... Q74FS9 23240087
    227711 4gvl:A (3.0) BS02 AMP ? GO:0006813 ... Q74FS9 23240087
    227712 4gvl:A (3.0) BS03 CA ? GO:0006813 ... Q74FS9 23240087
    227713 4gvl:A (3.0) BS04 CA ? GO:0006813 ... Q74FS9 23240087
    227714 4gvl:B (3.0) BS01 CA ? GO:0006813 ... Q74FS9 23240087
    227715 4gvl:B (3.0) BS02 ZN ? GO:0006813 ... Q74FS9 23240087
    227716 4gvl:B (3.0) BS03 AMP ? GO:0006813 ... Q74FS9 23240087
    227717 4gvl:B (3.0) BS04 CA ? GO:0006813 ... Q74FS9 23240087
    227718 4gvl:C (3.0) BS01 CA ? GO:0006813 ... Q74FS9 23240087
    227719 4gvl:C (3.0) BS02 ZN ? GO:0006813 ... Q74FS9 23240087
    227720 4gvl:C (3.0) BS03 AMP ? GO:0006813 ... Q74FS9 23240087
    227721 4gvl:C (3.0) BS04 CA ? GO:0006813 ... Q74FS9 23240087
    227722 4gvl:D (3.0) BS01 CA ? GO:0006813 ... Q74FS9 23240087
    227723 4gvl:D (3.0) BS02 CA ? GO:0006813 ... Q74FS9 23240087
    227724 4gvl:D (3.0) BS03 ZN ? GO:0006813 ... Q74FS9 23240087
    227725 4gvl:D (3.0) BS04 AMP ? GO:0006813 ... Q74FS9 23240087
    227726 4gvm:A (2.16) BS01 LF2 2.7.7.-
    2.7.7.49
    2.7.7.7
    3.1.-.-
    3.1.13.2
    3.1.26.13
    3.4.23.16
    GO:0003676 ... P12497 23615903 MOAD: ic50=1.49uM
    BindingDB: IC50=1.7e+2nM
    227727 4gvo:A (1.448) BS01 HIS ? N/A Q8Y4T3 N/A
    227728 4gvo:A (1.448) BS02 CSX ? N/A Q8Y4T3 N/A
    227729 4gvo:B (1.448) BS01 HIS ? N/A Q8Y4T3 N/A
    227730 4gvo:B (1.448) BS02 CSX ? N/A Q8Y4T3 N/A
    227731 4gvq:A (1.3) BS01 N4M 3.5.4.27 GO:0005737 ... O28344 23013430
    227732 4gvq:B (1.3) BS01 N4M 3.5.4.27 GO:0005737 ... O28344 23013430
    227733 4gvs:B (1.75) BS01 F4M 3.5.4.27 GO:0005737 ... O28344 23013430
    227734 4gvt:A (2.9) BS01 0SG ? GO:0005515 ... Q9NZD2 23519669
    227735 4gvu:A (1.55) BS01 peptide 3.4.21.36 GO:0004252 ... P00772 23350733
    227736 4gvu:A (1.55) BS02 CA 3.4.21.36 GO:0004252 ... P00772 23350733
    227737 4gvx:A (1.499) BS01 NAP 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227738 4gvx:A (1.499) BS02 FUL 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227739 4gvx:B (1.499) BS01 NAP 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227740 4gvx:B (1.499) BS02 FUL 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227741 4gvx:C (1.499) BS01 NAP 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227742 4gvx:C (1.499) BS02 FUL 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227743 4gvx:D (1.499) BS01 NAP 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227744 4gvx:D (1.499) BS02 FUL 1.1.1.435 GO:0019317 ... A0A0H3KNE7 N/A
    227745 4gvy:A (2.091) BS01 ADP 2.7.3.3 GO:0003824 ... P51541 22995310
    227746 4gvy:A (2.091) BS02 CIR 2.7.3.3 GO:0003824 ... P51541 22995310
    227747 4gvz:A (2.96) BS01 ADP 2.7.3.3 GO:0003824 ... P51541 22995310
    227748 4gvz:A (2.96) BS02 NO3 2.7.3.3 GO:0003824 ... P51541 22995310
    227749 4gvz:A (2.96) BS03 DAR 2.7.3.3 GO:0003824 ... P51541 22995310
    227750 4gw0:A (2.448) BS01 ADP 2.7.3.3 GO:0003824 ... P51541 22995310
    227751 4gw0:A (2.448) BS02 ILO 2.7.3.3 GO:0003824 ... P51541 22995310
    227752 4gw0:A (2.448) BS03 NO3 2.7.3.3 GO:0003824 ... P51541 22995310
    227753 4gw1:A (2.24) BS01 peptide N/A N/A N/A 24101516
    227754 4gw1:B (2.24) BS01 peptide N/A N/A N/A 24101516
    227755 4gw1:C (2.24) BS01 peptide N/A N/A N/A 24101516
    227756 4gw1:D (2.24) BS01 peptide N/A N/A N/A 24101516
    227757 4gw2:A (2.157) BS01 ADP 2.7.3.3 GO:0003824 ... P51541 22995310
    227758 4gw2:A (2.157) BS02 ORN 2.7.3.3 GO:0003824 ... P51541 22995310
    227759 4gw2:A (2.157) BS03 NO3 2.7.3.3 GO:0003824 ... P51541 22995310
    227760 4gw3:A (2.0) BS01 CA 3.1.1.3 GO:0004806 ... B4EVM3 23300806
    227761 4gw3:A (2.0) BS02 CA 3.1.1.3 GO:0004806 ... B4EVM3 23300806
    227762 4gw3:A (2.0) BS03 GOL 3.1.1.3 GO:0004806 ... B4EVM3 23300806
    227763 4gw5:A (2.2) BS01 peptide N/A N/A N/A 24101516
    227764 4gw5:B (2.2) BS01 peptide N/A N/A N/A 24101516
    227765 4gw5:C (2.2) BS01 peptide N/A N/A N/A 24101516
    227766 4gw5:D (2.2) BS01 peptide N/A N/A N/A 24101516
    227767 4gw6:A (2.65) BS01 LF2 2.7.7.-
    2.7.7.49
    2.7.7.7
    3.1.-.-
    3.1.13.2
    3.1.26.13
    3.4.23.16
    GO:0003676 ... P12497 23615903 BindingDB: IC50=1.7e+2nM
    227768 4gw8:A (2.0) BS01 peptide 2.7.11.1 GO:0004672 ... P11309 22998443
    227769 4gw8:A (2.0) BS02 3RA 2.7.11.1 GO:0004672 ... P11309 22998443 MOAD: ic50=0.88uM
    227770 4gw9:A (2.9) BS01 BLA N/A GO:0006355 ... N/A 22795083
    227771 4gw9:B (2.9) BS01 BLA N/A GO:0006355 ... N/A 22795083
    227772 4gw9:C (2.9) BS01 BLA N/A GO:0006355 ... N/A 22795083
    227773 4gw9:D (2.9) BS01 BLA N/A GO:0006355 ... N/A 22795083
    227774 4gwc:A (1.9) BS01 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227775 4gwc:A (1.9) BS02 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227776 4gwc:B (1.9) BS01 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227777 4gwc:B (1.9) BS02 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227778 4gwd:A (1.53) BS01 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227779 4gwd:A (1.53) BS02 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227780 4gwd:A (1.53) BS03 ZN 3.5.3.1 GO:0000050 ... P05089 23061982
    227781 4gwd:A (1.53) BS04 ABH 3.5.3.1 GO:0000050 ... P05089 23061982
    227782 4gwd:B (1.53) BS01 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227783 4gwd:B (1.53) BS02 MN 3.5.3.1 GO:0000050 ... P05089 23061982
    227784 4gwd:B (1.53) BS03 ZN 3.5.3.1 GO:0000050 ... P05089 23061982
    227785 4gwd:B (1.53) BS04 ABH 3.5.3.1 GO:0000050 ... P05089 23061982
    227786 4gwe:A (1.45) BS01 FMN 1.6.99.1 GO:0003959 ... Q02899 N/A
    227787 4gwe:A (1.45) BS02 07V 1.6.99.1 GO:0003959 ... Q02899 N/A
    227788 4gwi:A (1.6) BS01 FUC ? N/A Q2PHL4 23181061
    227789 4gwi:A (1.6) BS02 MG ? N/A Q2PHL4 23181061
    227790 4gwi:A (1.6) BS03 CA ? N/A Q2PHL4 23181061
    227791 4gwj:A (1.6) BS01 FUC ? N/A Q2PHL4 23181061
    227792 4gwj:A (1.6) BS02 MG ? N/A Q2PHL4 23181061
    227793 4gwj:A (1.6) BS03 CA ? N/A Q2PHL4 23181061
    227794 4gwm:A (1.85) BS01 MAN 3.4.24.63 GO:0004222 ... Q16820 22988105
    227795 4gwm:A (1.85) BS02 MAN 3.4.24.63 GO:0004222 ... Q16820 22988105
    227796 4gwm:A (1.85) BS03 ZN 3.4.24.63 GO:0004222 ... Q16820 22988105
    227797 4gwm:B (1.85) BS01 MAN 3.4.24.63 GO:0004222 ... Q16820 22988105
    227798 4gwm:B (1.85) BS02 MAN 3.4.24.63 GO:0004222 ... Q16820 22988105
    227799 4gwm:B (1.85) BS03 MAN 3.4.24.63 GO:0004222 ... Q16820 22988105
    227800 4gwm:B (1.85) BS04 ZN 3.4.24.63 GO:0004222 ... Q16820 22988105

    Reference:
  • Chengxin Zhang, Xi Zhang, Lydia Freddolino, and Yang Zhang. BioLiP2: an updated structure database for biologically relevent ligand-protein interactions, Nucleic Acids Research, gkad630 (2023).
  • Jianyi Yang, Ambrish Roy, and Yang Zhang. BioLiP: a semi-manually curated database for biologically relevant ligand-protein interactions, Nucleic Acids Research, 41: D1096-D1103 (2013) (download the PDF file).