9IT5: P300 KAT domain

p300 KAT domain in complex with KB528. Determined by X-ray diffraction at 2.0 Å resolution. Released 23 Jul 2025.

Method: X-ray diffraction
Resolution: 2.0 Å
Organism: Homo sapiens
Chains: 2
Atoms: 6,007
Mol. weight: 82.09 kDa
Ligands: A1L3B
Released: 23 Jul 2025

Explore 9IT5 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9IT5 contains 47 α-helices and 20 β-strands across 2 chains. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 24 helices, 10 β-strands

Element	Residues	Length	Sheet
α-helix	1290-1292	3
α-helix	1294-1295	2
α-helix	1297-1313	17
β-strand	1321-1334	14	1
α-helix	1335-1336	2
α-helix	1337-1339	3
α-helix	1340-1344	5
β-strand	1352-1366	15	1
β-strand	1369-1381	13	1
α-helix	1386	1
β-strand	1392-1400	9	1
α-helix	1407-1409	3
α-helix	1410-1428	19
β-strand	1432-1436	5	1
α-helix	1438-1440	3
β-strand	1441	1	2
β-strand	1444	1	2
α-helix	1455-1459	5
α-helix	1460-1476	17
β-strand	1482-1485	4	1
α-helix	1486-1493	8
α-helix	1498-1500	3
α-helix	1508-1522	15
α-helix	1558-1561	4
α-helix	1579-1590	12
α-helix	1592-1594	3
β-strand	1595-1599	5	1
α-helix	1603-1607	5
α-helix	1609-1612	4
α-helix	1617-1618	2
β-strand	1619	1	1
α-helix	1622-1624	3
α-helix	1628-1636	9
α-helix	1644-1660	17

Chain B: 23 helices, 10 β-strands

Element	Residues	Length	Sheet
α-helix	1290-1292	3
α-helix	1294-1295	2
α-helix	1297-1313	17
β-strand	1321-1334	14	3
α-helix	1335-1336	2
α-helix	1337-1339	3
α-helix	1340-1344	5
β-strand	1352-1365	14	3
β-strand	1370-1381	12	3
α-helix	1386	1
β-strand	1392-1400	9	3
α-helix	1407-1409	3
α-helix	1410-1428	19
β-strand	1432-1436	5	3
β-strand	1441	1	4
β-strand	1444	1	4
α-helix	1455-1459	5
α-helix	1460-1476	17
β-strand	1482-1485	4	3
α-helix	1486-1492	7
α-helix	1498-1500	3
α-helix	1508-1521	14
α-helix	1558-1560	3
α-helix	1576-1590	15
α-helix	1592-1594	3
β-strand	1595-1599	5	3
α-helix	1603-1607	5
α-helix	1609-1612	4
α-helix	1617-1618	2
β-strand	1619	1	3
α-helix	1622-1624	3
α-helix	1628-1636	9
α-helix	1644-1659	16

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Histone acetyltransferase p300	A, B	protein	349	Homo sapiens	Q09472 (AlphaFold model)

Sequence of entity 1 (A, B), FASTA

>9IT5_1 Histone acetyltransferase p300 (chains A, B)
MKFSAKRLPSTRLGTFLENRVNDFLRRQNHPESGEVTVRVVHASDKTVEVKPGMKARFVD
SGEMAESFPYRTKALFAFEEIDGVDLCFFGMHVQEYGSDCPPPNQRRVYISYLDSVHFFR
PKCLRTAVYHEILIGYLEYVKKLGYTTGHIWACPPSEGDDYIFHCHPPDQKIPKPKRLQE
WYKKMLDKAVSERIVHDYKDIFKQATEDRLTSAKELPYFEGDFWPNVLEESIKELEQKTS
KNKSSLSRGNKKKPGMPNVSNDLSQKLYATMEKHKEVFFVIRLIAGPAANSLPPIVDPDP
LIPCDLMDGRDAFLTLARDRHLEFSSLRRAQWSTGCMLVELHTQSQDRF

Ligands and cofactors

ID	Name	Formula	Copies
A1L3B	4-[(2~{S})-1-[[(~{R})-[(3~{S})-7-(1-methylpyrazol-4-yl)-2,3-dihydro-1~{H}-pyrid…	C28 H28 N6 O	2

Water and common crystallization additives (EDO, GOL, CL) are not listed.

Primary citation

Catalytic Inhibition of p300 Preferentially Targets IRF4 Oncogenic Activity and Tumor Growth in Multiple Myeloma. Lenoir, W.F., McKeown, M.R., Giorgetti, G. et al. Cancer Res (2026) 86:1010-1034. DOI 10.1158/0008-5472.CAN-25-3440 · PubMed

Other PDB entries of the same protein (UniProt Q09472 (AlphaFold model), which also has an AlphaFold model), best resolution first:

5BT3 1.05 Å, Crystal structure of EP300 bromodomain in complex with SGC-CBP30 chemical probe
3T92 1.5 Å, Crystal structure of the Taz2:C/EBPepsilon-TAD chimera protein
5LPM 1.5 Å, Crystal structure of the bromodomain of human Ep300 bound to the inhibitor XDM3d
5NU5 1.6 Å, Crystal structure of the human bromodomain of EP300 bound to the inhibitor XDM-CBP
3BIY 1.7 Å, Crystal structure of p300 histone acetyltransferase domain in complex with a bisubstrate…
6PGU 1.72 Å, Crystal structure of the p300 acetyltransferase domain with allosteric inhibitor CPI-076…
6V8K 1.84 Å, Crystal structure of the p300 acetyltransferase domain with peptide-competitive…
4PZS 1.94 Å, Crystal structure of p300 histone acetyltransferase domain in complex with…
5KJ2 1.95 Å, The novel p300/CBP inhibitor A-485 uncovers a unique mechanism of action to target AR in…
6DS6 1.95 Å, Crystal structure of p300 ZZ domain in complex with histone H3 peptide
7QGS 2.0 Å, Crystal structure of p300 CH1 domain in complex with CITIF (a CITED2-HIF-1alpha hybrid)
7UGI 2.0 Å, Bromodomain of EP300 liganded with BMS-536924

Browse structure collections

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