1SAC: Pentameric human serum amyloid P component

The structure of pentameric human serum amyloid P component. Determined by X-ray diffraction at 2.0 Å resolution. Released 31 May 1994.

Method: X-ray diffraction
Resolution: 2.0 Å
Organism: Homo sapiens
Chains: 5
Atoms: 8,271
Mol. weight: 117.05 kDa
Ligands: CA
Released: 31 May 1994

Explore 1SAC in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

1SAC contains 21 α-helices and 100 β-strands across 5 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: 3 helices, 20 β-strands

Element	Residues	Length	Sheet
β-strand	2	1	1
β-strand	7-11	5	2
β-strand	19-22	4	3
β-strand	30	1	4
β-strand	32-40	9	2
β-strand	47-54	8	3
β-strand	57-67	11	3
β-strand	70-75	6	3
β-strand	78-83	6	3
β-strand	92-99	8	2
β-strand	104-109	6	2
β-strand	112-113	2	2
β-strand	117-118	2	2
β-strand	125	1	4
β-strand	130-133	4	3
α-helix	146-148	3
β-strand	152-160	9	2
α-helix	166-173	8
α-helix	177-180	4
β-strand	183-184	2	2
β-strand	188	1	1
β-strand	190-193	4	3
β-strand	197-200	4	2

Chain B: 6 helices, 20 β-strands

Element	Residues	Length	Sheet
β-strand	2	1	5
β-strand	7-11	5	6
β-strand	19-22	4	7
α-helix	29	1
β-strand	30	1	8
β-strand	32-40	9	6
β-strand	47-54	8	7
β-strand	57-67	11	7
β-strand	70-75	6	7
β-strand	78-83	6	7
β-strand	92-99	8	6
β-strand	104-109	6	6
β-strand	112-113	2	6
α-helix	114-116	3
β-strand	117-118	2	6
β-strand	125	1	8
β-strand	130-133	4	7
α-helix	146-148	3
β-strand	152-160	9	6
α-helix	163-165	3
α-helix	166-173	8
α-helix	177-180	4
β-strand	183-184	2	6
β-strand	188	1	5
β-strand	190-193	4	7
β-strand	197-200	4	6

Chain C: 4 helices, 20 β-strands

Element	Residues	Length	Sheet
β-strand	2	1	9
β-strand	7-10	4	10
β-strand	19-22	4	11
β-strand	30	1	12
β-strand	32-40	9	10
β-strand	47-54	8	11
β-strand	57-67	11	11
β-strand	70-75	6	11
β-strand	78-83	6	11
β-strand	92-99	8	10
β-strand	104-109	6	10
β-strand	112-113	2	10
α-helix	114-116	3
β-strand	117-118	2	10
β-strand	125	1	12
β-strand	130-133	4	11
α-helix	146-148	3
β-strand	153-160	8	10
α-helix	166-174	9
α-helix	177-179	3
β-strand	183	1	10
β-strand	188	1	9
β-strand	190-193	4	11
β-strand	197-200	4	10

Chain D: 4 helices, 20 β-strands

Element	Residues	Length	Sheet
β-strand	2	1	13
β-strand	7-11	5	14
β-strand	19-23	5	15
α-helix	29	1
β-strand	30	1	16
β-strand	32-40	9	14
β-strand	47-54	8	15
β-strand	57-67	11	15
β-strand	70-75	6	15
β-strand	78-83	6	15
β-strand	92-99	8	14
β-strand	104-109	6	14
β-strand	112-113	2	14
β-strand	117-118	2	14
β-strand	125	1	16
β-strand	130-133	4	15
α-helix	146-148	3
β-strand	152-160	9	14
α-helix	166-174	9
α-helix	177-180	4
β-strand	183-184	2	14
β-strand	188	1	13
β-strand	189-193	5	15
β-strand	197-200	4	14

Chain E: 4 helices, 20 β-strands

Element	Residues	Length	Sheet
β-strand	2	1	17
β-strand	7-11	5	18
β-strand	19-22	4	19
α-helix	29	1
β-strand	30	1	20
β-strand	32-40	9	18
β-strand	47-54	8	19
β-strand	57-67	11	19
β-strand	70-75	6	19
β-strand	78-83	6	19
β-strand	92-99	8	18
β-strand	104-109	6	18
β-strand	112-113	2	18
β-strand	117-118	2	18
β-strand	125	1	20
β-strand	130-133	4	19
α-helix	146-148	3
β-strand	152-160	9	18
α-helix	166-173	8
α-helix	177-179	3
β-strand	183-184	2	18
β-strand	188	1	17
β-strand	190-193	4	19
β-strand	197-200	4	18

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Serum amyloid P component	A, B, C, D, E	protein	204	Homo sapiens	P02743 (AlphaFold model)

Sequence of entity 1 (A, B, C, D, E), FASTA

>1SAC_1 SERUM AMYLOID P COMPONENT (chains A, B, C, D, E)
HTDLSGKVFVFPRESVTDHVNLITPLEKPLQNFTLCFRAYSDLSRAYSLFSYNTQGRDNE
LLVYKERVGEYSLYIGRHKVTSKVIEKFPAPVHICVSWESSSGIAEFWINGTPLVKKGLR
QGYFVEAQPKIVLGQEQDSYGGKFDRSQSFVGEIGDLYMWDSVLPPENILSAYQGTPLPA
NILDWQALNYEIRGYVIIKPLVWV

Ligands and cofactors

ID	Name	Formula	Copies
CA	Calcium ion	Ca	10

Water and common crystallization additives (ACY) are not listed.

Primary citation

Structure of pentameric human serum amyloid P component. Emsley, J., White, H.E., O'Hara, B.P. et al. Nature (1994) 367:338-345. DOI 10.1038/367338a0 · PubMed

Other PDB entries of the same protein (UniProt P02743 (AlphaFold model), which also has an AlphaFold model), best resolution first:

4AVS 1.4 Å, Structure of N-Acetyl-L-Proline bound to Serum Amyloid P Component
3KQR 1.5 Å, The structure of serum amyloid p component bound to phosphoethanolamine
4AYU 1.5 Å, Structure of N-Acetyl-D-Proline bound to serum amyloid P component
4AVV 1.6 Å, Structure of CPHPC bound to Serum Amyloid P Component
2W08 1.7 Å, The structure of serum amyloid P component bound to 0-phospho- threonine
2A3Y 2.0 Å, Pentameric crystal structure of human serum amyloid P-component bound to…
1GYK 2.2 Å, Serum Amyloid P Component co-crystallised with MOBDG at neutral pH
2A3W 2.2 Å, Decameric structure of human serum amyloid P-component bound to…
1LGN 2.8 Å, Decameric damp complex of human serum amyloid P component
3D5O 2.8 Å, Structural recognition and functional activation of FcrR by innate pentraxins
2A3X 3.0 Å, Decameric crystal structure of human serum amyloid P-component bound to…
4AVT 3.2 Å, Structure of CPHPC bound to Serum Amyloid P Component

Browse structure collections

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