2B8K

12-subunit RNA Polymerase II

Functional Information from GO Data

Chain	GOid	namespace	contents
A	0000428	cellular_component	DNA-directed RNA polymerase complex
A	0001054	molecular_function	RNA polymerase I activity
A	0001055	molecular_function	RNA polymerase II activity
A	0001056	molecular_function	RNA polymerase III activity
A	0001057	molecular_function	RNA polymerase IV activity
A	0001058	molecular_function	RNA polymerase V activity
A	0001059	biological_process	transcription by RNA polymerase IV
A	0001060	biological_process	transcription by RNA polymerase V
A	0001065	molecular_function	mitochondrial single subunit type RNA polymerase activity
A	0001066	molecular_function	plastid single subunit type RNA polymerase activity
A	0001172	biological_process	RNA-templated transcription
A	0003677	molecular_function	DNA binding
A	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
A	0003968	molecular_function	RNA-dependent RNA polymerase activity
A	0005515	molecular_function	protein binding
A	0005634	cellular_component	nucleus
A	0005665	cellular_component	RNA polymerase II, core complex
A	0005739	cellular_component	mitochondrion
A	0006351	biological_process	DNA-templated transcription
A	0006360	biological_process	transcription by RNA polymerase I
A	0006366	biological_process	transcription by RNA polymerase II
A	0006367	biological_process	transcription initiation at RNA polymerase II promoter
A	0006368	biological_process	transcription elongation by RNA polymerase II
A	0006383	biological_process	transcription by RNA polymerase III
A	0006390	biological_process	mitochondrial transcription
A	0008270	molecular_function	zinc ion binding
A	0010494	cellular_component	cytoplasmic stress granule
A	0016779	molecular_function	nucleotidyltransferase activity
A	0019985	biological_process	translesion synthesis
A	0034062	molecular_function	5'-3' RNA polymerase activity
A	0042793	biological_process	plastid transcription
A	0046872	molecular_function	metal ion binding
B	0000428	cellular_component	DNA-directed RNA polymerase complex
B	0001054	molecular_function	RNA polymerase I activity
B	0001055	molecular_function	RNA polymerase II activity
B	0001056	molecular_function	RNA polymerase III activity
B	0001057	molecular_function	RNA polymerase IV activity
B	0001058	molecular_function	RNA polymerase V activity
B	0001059	biological_process	transcription by RNA polymerase IV
B	0001060	biological_process	transcription by RNA polymerase V
B	0001065	molecular_function	mitochondrial single subunit type RNA polymerase activity
B	0001066	molecular_function	plastid single subunit type RNA polymerase activity
B	0001172	biological_process	RNA-templated transcription
B	0003677	molecular_function	DNA binding
B	0003729	molecular_function	mRNA binding
B	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
B	0003968	molecular_function	RNA-dependent RNA polymerase activity
B	0005515	molecular_function	protein binding
B	0005634	cellular_component	nucleus
B	0005665	cellular_component	RNA polymerase II, core complex
B	0005739	cellular_component	mitochondrion
B	0006351	biological_process	DNA-templated transcription
B	0006360	biological_process	transcription by RNA polymerase I
B	0006366	biological_process	transcription by RNA polymerase II
B	0006367	biological_process	transcription initiation at RNA polymerase II promoter
B	0006368	biological_process	transcription elongation by RNA polymerase II
B	0006383	biological_process	transcription by RNA polymerase III
B	0006390	biological_process	mitochondrial transcription
B	0008270	molecular_function	zinc ion binding
B	0010494	cellular_component	cytoplasmic stress granule
B	0016779	molecular_function	nucleotidyltransferase activity
B	0032549	molecular_function	ribonucleoside binding
B	0034062	molecular_function	5'-3' RNA polymerase activity
B	0042793	biological_process	plastid transcription
B	0046872	molecular_function	metal ion binding
C	0000428	cellular_component	DNA-directed RNA polymerase complex
C	0001055	molecular_function	RNA polymerase II activity
C	0001172	biological_process	RNA-templated transcription
C	0003677	molecular_function	DNA binding
C	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
C	0003968	molecular_function	RNA-dependent RNA polymerase activity
C	0005515	molecular_function	protein binding
C	0005634	cellular_component	nucleus
C	0005654	cellular_component	nucleoplasm
C	0005665	cellular_component	RNA polymerase II, core complex
C	0006351	biological_process	DNA-templated transcription
C	0006366	biological_process	transcription by RNA polymerase II
C	0006367	biological_process	transcription initiation at RNA polymerase II promoter
C	0006368	biological_process	transcription elongation by RNA polymerase II
C	0006369	biological_process	termination of RNA polymerase II transcription
C	0008270	molecular_function	zinc ion binding
C	0046872	molecular_function	metal ion binding
C	0046983	molecular_function	protein dimerization activity
C	0055029	cellular_component	nuclear DNA-directed RNA polymerase complex
D	0000166	molecular_function	nucleotide binding
D	0000288	biological_process	nuclear-transcribed mRNA catabolic process, deadenylation-dependent decay
D	0000428	cellular_component	DNA-directed RNA polymerase complex
D	0000932	cellular_component	P-body
D	0001172	biological_process	RNA-templated transcription
D	0003697	molecular_function	single-stranded DNA binding
D	0003727	molecular_function	single-stranded RNA binding
D	0003968	molecular_function	RNA-dependent RNA polymerase activity
D	0005515	molecular_function	protein binding
D	0005634	cellular_component	nucleus
D	0005665	cellular_component	RNA polymerase II, core complex
D	0005737	cellular_component	cytoplasm
D	0006352	biological_process	DNA-templated transcription initiation
D	0006366	biological_process	transcription by RNA polymerase II
D	0006367	biological_process	transcription initiation at RNA polymerase II promoter
D	0006368	biological_process	transcription elongation by RNA polymerase II
D	0006397	biological_process	mRNA processing
D	0030880	cellular_component	RNA polymerase complex
D	0031369	molecular_function	translation initiation factor binding
D	0044237	biological_process	cellular metabolic process
D	0045948	biological_process	positive regulation of translational initiation
D	1990328	cellular_component	RPB4-RPB7 complex
E	0000428	cellular_component	DNA-directed RNA polymerase complex
E	0001054	molecular_function	RNA polymerase I activity
E	0001055	molecular_function	RNA polymerase II activity
E	0001056	molecular_function	RNA polymerase III activity
E	0001172	biological_process	RNA-templated transcription
E	0003677	molecular_function	DNA binding
E	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
E	0003968	molecular_function	RNA-dependent RNA polymerase activity
E	0005515	molecular_function	protein binding
E	0005634	cellular_component	nucleus
E	0005654	cellular_component	nucleoplasm
E	0005665	cellular_component	RNA polymerase II, core complex
E	0005666	cellular_component	RNA polymerase III complex
E	0005736	cellular_component	RNA polymerase I complex
E	0006351	biological_process	DNA-templated transcription
E	0006360	biological_process	transcription by RNA polymerase I
E	0006361	biological_process	transcription initiation at RNA polymerase I promoter
E	0006362	biological_process	transcription elongation by RNA polymerase I
E	0006363	biological_process	termination of RNA polymerase I transcription
E	0006366	biological_process	transcription by RNA polymerase II
E	0006367	biological_process	transcription initiation at RNA polymerase II promoter
E	0006368	biological_process	transcription elongation by RNA polymerase II
E	0006383	biological_process	transcription by RNA polymerase III
E	0006384	biological_process	transcription initiation at RNA polymerase III promoter
E	0006386	biological_process	termination of RNA polymerase III transcription
E	0042254	biological_process	ribosome biogenesis
E	0042790	biological_process	nucleolar large rRNA transcription by RNA polymerase I
E	0042797	biological_process	tRNA transcription by RNA polymerase III
F	0000428	cellular_component	DNA-directed RNA polymerase complex
F	0001054	molecular_function	RNA polymerase I activity
F	0001055	molecular_function	RNA polymerase II activity
F	0001056	molecular_function	RNA polymerase III activity
F	0001172	biological_process	RNA-templated transcription
F	0003677	molecular_function	DNA binding
F	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
F	0003968	molecular_function	RNA-dependent RNA polymerase activity
F	0005515	molecular_function	protein binding
F	0005634	cellular_component	nucleus
F	0005654	cellular_component	nucleoplasm
F	0005665	cellular_component	RNA polymerase II, core complex
F	0005666	cellular_component	RNA polymerase III complex
F	0005736	cellular_component	RNA polymerase I complex
F	0005737	cellular_component	cytoplasm
F	0006351	biological_process	DNA-templated transcription
F	0006360	biological_process	transcription by RNA polymerase I
F	0006361	biological_process	transcription initiation at RNA polymerase I promoter
F	0006362	biological_process	transcription elongation by RNA polymerase I
F	0006363	biological_process	termination of RNA polymerase I transcription
F	0006366	biological_process	transcription by RNA polymerase II
F	0006367	biological_process	transcription initiation at RNA polymerase II promoter
F	0006368	biological_process	transcription elongation by RNA polymerase II
F	0006383	biological_process	transcription by RNA polymerase III
F	0006384	biological_process	transcription initiation at RNA polymerase III promoter
F	0006386	biological_process	termination of RNA polymerase III transcription
F	0042254	biological_process	ribosome biogenesis
F	0042790	biological_process	nucleolar large rRNA transcription by RNA polymerase I
F	0042797	biological_process	tRNA transcription by RNA polymerase III
G	0000288	biological_process	nuclear-transcribed mRNA catabolic process, deadenylation-dependent decay
G	0000428	cellular_component	DNA-directed RNA polymerase complex
G	0000932	cellular_component	P-body
G	0000956	biological_process	nuclear-transcribed mRNA catabolic process
G	0001172	biological_process	RNA-templated transcription
G	0003676	molecular_function	nucleic acid binding
G	0003697	molecular_function	single-stranded DNA binding
G	0003727	molecular_function	single-stranded RNA binding
G	0003968	molecular_function	RNA-dependent RNA polymerase activity
G	0005515	molecular_function	protein binding
G	0005634	cellular_component	nucleus
G	0005665	cellular_component	RNA polymerase II, core complex
G	0005737	cellular_component	cytoplasm
G	0006351	biological_process	DNA-templated transcription
G	0006352	biological_process	DNA-templated transcription initiation
G	0006366	biological_process	transcription by RNA polymerase II
G	0006367	biological_process	transcription initiation at RNA polymerase II promoter
G	0006368	biological_process	transcription elongation by RNA polymerase II
G	0031369	molecular_function	translation initiation factor binding
G	0045948	biological_process	positive regulation of translational initiation
G	0055029	cellular_component	nuclear DNA-directed RNA polymerase complex
G	0060213	biological_process	positive regulation of nuclear-transcribed mRNA poly(A) tail shortening
G	1990328	cellular_component	RPB4-RPB7 complex
H	0000428	cellular_component	DNA-directed RNA polymerase complex
H	0001054	molecular_function	RNA polymerase I activity
H	0001055	molecular_function	RNA polymerase II activity
H	0001056	molecular_function	RNA polymerase III activity
H	0001172	biological_process	RNA-templated transcription
H	0003677	molecular_function	DNA binding
H	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
H	0003968	molecular_function	RNA-dependent RNA polymerase activity
H	0005515	molecular_function	protein binding
H	0005634	cellular_component	nucleus
H	0005654	cellular_component	nucleoplasm
H	0005665	cellular_component	RNA polymerase II, core complex
H	0005666	cellular_component	RNA polymerase III complex
H	0005736	cellular_component	RNA polymerase I complex
H	0006351	biological_process	DNA-templated transcription
H	0006360	biological_process	transcription by RNA polymerase I
H	0006361	biological_process	transcription initiation at RNA polymerase I promoter
H	0006362	biological_process	transcription elongation by RNA polymerase I
H	0006363	biological_process	termination of RNA polymerase I transcription
H	0006366	biological_process	transcription by RNA polymerase II
H	0006367	biological_process	transcription initiation at RNA polymerase II promoter
H	0006368	biological_process	transcription elongation by RNA polymerase II
H	0006383	biological_process	transcription by RNA polymerase III
H	0006384	biological_process	transcription initiation at RNA polymerase III promoter
H	0006386	biological_process	termination of RNA polymerase III transcription
H	0042254	biological_process	ribosome biogenesis
H	0042790	biological_process	nucleolar large rRNA transcription by RNA polymerase I
H	0042797	biological_process	tRNA transcription by RNA polymerase III
I	0000428	cellular_component	DNA-directed RNA polymerase complex
I	0001172	biological_process	RNA-templated transcription
I	0001193	biological_process	maintenance of transcriptional fidelity during transcription elongation by RNA polymerase II
I	0003676	molecular_function	nucleic acid binding
I	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
I	0003968	molecular_function	RNA-dependent RNA polymerase activity
I	0005515	molecular_function	protein binding
I	0005634	cellular_component	nucleus
I	0005654	cellular_component	nucleoplasm
I	0005665	cellular_component	RNA polymerase II, core complex
I	0005730	cellular_component	nucleolus
I	0006281	biological_process	DNA repair
I	0006283	biological_process	transcription-coupled nucleotide-excision repair
I	0006351	biological_process	DNA-templated transcription
I	0006366	biological_process	transcription by RNA polymerase II
I	0006367	biological_process	transcription initiation at RNA polymerase II promoter
I	0006368	biological_process	transcription elongation by RNA polymerase II
I	0008270	molecular_function	zinc ion binding
I	0046872	molecular_function	metal ion binding
I	0055029	cellular_component	nuclear DNA-directed RNA polymerase complex
J	0000428	cellular_component	DNA-directed RNA polymerase complex
J	0001054	molecular_function	RNA polymerase I activity
J	0001055	molecular_function	RNA polymerase II activity
J	0001056	molecular_function	RNA polymerase III activity
J	0001172	biological_process	RNA-templated transcription
J	0003677	molecular_function	DNA binding
J	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
J	0003968	molecular_function	RNA-dependent RNA polymerase activity
J	0005515	molecular_function	protein binding
J	0005634	cellular_component	nucleus
J	0005654	cellular_component	nucleoplasm
J	0005665	cellular_component	RNA polymerase II, core complex
J	0005666	cellular_component	RNA polymerase III complex
J	0005730	cellular_component	nucleolus
J	0005736	cellular_component	RNA polymerase I complex
J	0006351	biological_process	DNA-templated transcription
J	0006360	biological_process	transcription by RNA polymerase I
J	0006361	biological_process	transcription initiation at RNA polymerase I promoter
J	0006362	biological_process	transcription elongation by RNA polymerase I
J	0006363	biological_process	termination of RNA polymerase I transcription
J	0006366	biological_process	transcription by RNA polymerase II
J	0006367	biological_process	transcription initiation at RNA polymerase II promoter
J	0006368	biological_process	transcription elongation by RNA polymerase II
J	0006383	biological_process	transcription by RNA polymerase III
J	0006384	biological_process	transcription initiation at RNA polymerase III promoter
J	0006386	biological_process	termination of RNA polymerase III transcription
J	0008270	molecular_function	zinc ion binding
J	0042254	biological_process	ribosome biogenesis
J	0042790	biological_process	nucleolar large rRNA transcription by RNA polymerase I
J	0042797	biological_process	tRNA transcription by RNA polymerase III
J	0046872	molecular_function	metal ion binding
K	0000428	cellular_component	DNA-directed RNA polymerase complex
K	0001055	molecular_function	RNA polymerase II activity
K	0001172	biological_process	RNA-templated transcription
K	0003677	molecular_function	DNA binding
K	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
K	0003968	molecular_function	RNA-dependent RNA polymerase activity
K	0005515	molecular_function	protein binding
K	0005634	cellular_component	nucleus
K	0005665	cellular_component	RNA polymerase II, core complex
K	0006351	biological_process	DNA-templated transcription
K	0006366	biological_process	transcription by RNA polymerase II
K	0006367	biological_process	transcription initiation at RNA polymerase II promoter
K	0006368	biological_process	transcription elongation by RNA polymerase II
K	0006369	biological_process	termination of RNA polymerase II transcription
K	0046983	molecular_function	protein dimerization activity
L	0000428	cellular_component	DNA-directed RNA polymerase complex
L	0001054	molecular_function	RNA polymerase I activity
L	0001055	molecular_function	RNA polymerase II activity
L	0001056	molecular_function	RNA polymerase III activity
L	0001172	biological_process	RNA-templated transcription
L	0003677	molecular_function	DNA binding
L	0003899	molecular_function	DNA-directed 5'-3' RNA polymerase activity
L	0003968	molecular_function	RNA-dependent RNA polymerase activity
L	0005634	cellular_component	nucleus
L	0005654	cellular_component	nucleoplasm
L	0005665	cellular_component	RNA polymerase II, core complex
L	0005666	cellular_component	RNA polymerase III complex
L	0005730	cellular_component	nucleolus
L	0005736	cellular_component	RNA polymerase I complex
L	0005737	cellular_component	cytoplasm
L	0005777	cellular_component	peroxisome
L	0006351	biological_process	DNA-templated transcription
L	0006360	biological_process	transcription by RNA polymerase I
L	0006361	biological_process	transcription initiation at RNA polymerase I promoter
L	0006362	biological_process	transcription elongation by RNA polymerase I
L	0006363	biological_process	termination of RNA polymerase I transcription
L	0006366	biological_process	transcription by RNA polymerase II
L	0006367	biological_process	transcription initiation at RNA polymerase II promoter
L	0006368	biological_process	transcription elongation by RNA polymerase II
L	0006383	biological_process	transcription by RNA polymerase III
L	0006384	biological_process	transcription initiation at RNA polymerase III promoter
L	0006386	biological_process	termination of RNA polymerase III transcription
L	0008270	molecular_function	zinc ion binding
L	0042254	biological_process	ribosome biogenesis
L	0042790	biological_process	nucleolar large rRNA transcription by RNA polymerase I
L	0042797	biological_process	tRNA transcription by RNA polymerase III
L	0046872	molecular_function	metal ion binding

Functional Information from PDB Data

site_id	AC1
Number of Residues	4
Details	BINDING SITE FOR RESIDUE ZN A 1734

Chain	Residue
A	MET108
A	CYS110
A	CYS148
A	CYS167

---

site_id	AC2
Number of Residues	5
Details	BINDING SITE FOR RESIDUE ZN A 1735

Chain	Residue
A	CYS67
A	GLN68
A	CYS70
A	CYS77
A	HIS80

---

site_id	AC3
Number of Residues	5
Details	BINDING SITE FOR RESIDUE ZN B 1225

Chain	Residue
B	CYS1163
B	CYS1166
B	THR1170
B	CYS1182
B	CYS1185

---

site_id	AC4
Number of Residues	4
Details	BINDING SITE FOR RESIDUE ZN C 319

Chain	Residue
C	CYS86
C	CYS88
C	CYS92
C	CYS95

---

site_id	AC5
Number of Residues	4
Details	BINDING SITE FOR RESIDUE ZN I 123

Chain	Residue
I	CYS7
I	CYS10
I	CYS29
I	CYS32

---

site_id	AC6
Number of Residues	4
Details	BINDING SITE FOR RESIDUE ZN I 124

Chain	Residue
I	CYS75
I	CYS78
I	CYS106
I	HIS108

---

site_id	AC7
Number of Residues	4
Details	BINDING SITE FOR RESIDUE ZN J 71

Chain	Residue
J	CYS7
J	CYS10
J	CYS45
J	CYS46

---

site_id	AC8
Number of Residues	4
Details	BINDING SITE FOR RESIDUE ZN L 71

Chain	Residue
L	CYS31
L	CYS34
L	CYS48
L	CYS51

---

Functional Information from PROSITE/UniProt

site_id	PS00115
Number of Residues	7
Details	RNA_POL_II_REPEAT Eukaryotic RNA polymerase II heptapeptide repeat. YSPTSPA

Chain	Residue	Details
A	TYR1549-ALA1555
A	TYR1612-SER1618
A	TYR1619-SER1625
A	TYR1626-SER1632
A	TYR1633-SER1639
A	TYR1640-SER1646
A	TYR1647-SER1653
A	TYR1654-ALA1660
A	TYR1661-SER1667
A	TYR1668-SER1674
A	TYR1675-SER1681
A	TYR1556-SER1562
A	TYR1682-SER1688
A	TYR1689-ASN1695
A	TYR1696-SER1702
A	TYR1563-SER1569
A	TYR1570-SER1576
A	TYR1577-SER1583
A	TYR1584-SER1590
A	TYR1591-SER1597
A	TYR1598-SER1604
A	TYR1605-SER1611

---

site_id	PS00446
Number of Residues	41
Details	RNA_POL_D_30KD RNA polymerases D / 30 to 40 Kd subunits signature. NSLRRvmiaeiptlAidsVevetNtTvlaDEfIAhRLGLIP

Chain	Residue	Details
C	ASN31-PRO71

---

site_id	PS00466
Number of Residues	36
Details	ZF_TFIIS_1 Zinc finger TFIIS-type signature. CpkChsrenvffqSQQRRkDTSmvlffvCls...CshiF

Chain	Residue	Details
I	CYS75-PHE110

---

site_id	PS01030
Number of Residues	27
Details	RNA_POL_M_15KD RNA polymerases M / 15 Kd subunits signature. FCRDCNNMLypredkennrllfeCrtC

Chain	Residue	Details
I	PHE6-CYS32

---

site_id	PS01110
Number of Residues	14
Details	RNA_POL_H_23KD RNA polymerases H / 23 Kd subunits signature. HELVPKHirLssDE

Chain	Residue	Details
E	HIS147-GLU160

---

site_id	PS01111
Number of Residues	15
Details	RNA_POL_K_14KD RNA polymerases K / 14 to 18 Kd subunits signature. TkYErARiLGtRAlQ

Chain	Residue	Details
F	THR86-GLN100

---

site_id	PS01112
Number of Residues	10
Details	RNA_POL_N_8KD RNA polymerases N / 8 Kd subunits signature. IVPVrCFSCG

Chain	Residue	Details
J	ILE2-GLY11

---

site_id	PS01154
Number of Residues	32
Details	RNA_POL_L_13KD RNA polymerases L / 13 to 16 Kd subunits signature. FekEdHTLgNlIraeLlndrkVlfaaYkveHP

Chain	Residue	Details
K	PHE35-PRO66

---

site_id	PS01166
Number of Residues	13
Details	RNA_POL_BETA RNA polymerases beta chain signature. GdKFASrHGQKGT

Chain	Residue	Details
B	GLY977-THR989

---

Functional Information from SwissProt/UniProt

site_id	SWS_FT_FI1
Number of Residues	20
Details	ZN_FING: C4-type

Chain	Residue	Details
L	CYS31-CYS51
A	ASP483
A	ASP485
J	CYS10
J	CYS45
J	CYS46
A	CYS107
A	CYS110
A	CYS148
A	CYS167
A	ASP481

---

site_id	SWS_FT_FI2
Number of Residues	4
Details	BINDING:

Chain	Residue	Details
L	CYS31
L	CYS34
L	CYS48
L	CYS51
B	CYS1185

---

site_id	SWS_FT_FI3
Number of Residues	4
Details	BINDING: BINDING => ECO:0000255|PROSITE-ProRule:PRU10145, ECO:0000269|PubMed:11313498, ECO:0000269|PubMed:11805306, ECO:0000269|PubMed:15537538, ECO:0000305|PubMed:11313499

Chain	Residue	Details
I	CYS7
I	CYS10
I	CYS29
I	CYS32

---

site_id	SWS_FT_FI4
Number of Residues	4
Details	BINDING: BINDING => ECO:0000255|PROSITE-ProRule:PRU00472, ECO:0000269|PubMed:11313498, ECO:0000269|PubMed:11805306, ECO:0000269|PubMed:15537538, ECO:0000305|PubMed:11313499

Chain	Residue	Details
I	CYS75
I	CYS78
I	CYS103
I	CYS106

---

site_id	SWS_FT_FI5
Number of Residues	1
Details	MOD_RES: Phosphoserine => ECO:0007744|PubMed:18407956

Chain	Residue	Details
I	SER40

---

Catalytic Information from CSA

site_id	MCSA1
Number of Residues	1
Details	M-CSA 788

Chain	Residue	Details
B	ASP837	metal ligand
A	ASP483	metal ligand
A	ASP485	metal ligand
A	HIS1085	proton acceptor, proton donor

---