2NSI: Protein

Human inducible nitric oxide synthase, ZN-free, seitu complex. Determined by X-ray diffraction at 3.0 Å resolution. Released 7 Jan 2000.

Method: X-ray diffraction
Resolution: 3.0 Å
Organism: Homo sapiens
Chains: 4
Atoms: 13,985
Mol. weight: 203.53 kDa
Ligands: HEM, ITU, H4B
Released: 7 Jan 2000

Explore 2NSI in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

2NSI contains 119 α-helices and 106 β-strands across 4 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.

Chains A and C: 30 helices, 26 β-strands

Element	Residues	Length	Sheet
β-strand	85-88	4	1
β-strand	89	1	2
β-strand	95-98	4	1
α-helix	100-102	3
β-strand	115	1	3
α-helix	123-125	3
β-strand	126	1	4
α-helix	133-135	3
α-helix	136-153	18
α-helix	159-176	18
α-helix	183-195	13
α-helix	203-205	3
β-strand	210-213	4	5
α-helix	220-235	16
α-helix	236-238	3
β-strand	243-246	4	5
β-strand	258-259	2	6
β-strand	263	1	5
β-strand	267	1	7
β-strand	269-271	3	8
β-strand	277-279	3	8
α-helix	281-283	3
α-helix	284-292	9
α-helix	295-297	3
α-helix	303	1
β-strand	304	1	7
α-helix	305-306	2
β-strand	307-310	4	6
α-helix	314-316	3
β-strand	317-319	3	6
α-helix	320-322	3
α-helix	323-325	3
β-strand	328-330	3	9
α-helix	339-342	4
β-strand	345-347	3	9
β-strand	351-352	2	5
β-strand	355-359	5	4
β-strand	362-364	3	4
β-strand	369-370	2	5
β-strand	374	1	10
α-helix	375-376	2
α-helix	377-382	6
α-helix	383-384	2
α-helix	392-398	7
α-helix	406-408	3
α-helix	410-428	19
β-strand	434	1	10
α-helix	436-453	18
α-helix	461-464	4
α-helix	470-472	3
α-helix	474-477	4
β-strand	478	1	2
β-strand	482	1	11
β-strand	488-491	4	4
α-helix	495-498	4
α-helix	499-501	3

Chain B: 29 helices, 27 β-strands

Element	Residues	Length	Sheet
β-strand	85-88	4	12
β-strand	89	1	13
β-strand	95-98	4	12
α-helix	100-102	3
β-strand	115	1	11
α-helix	123-125	3
β-strand	126	1	14
α-helix	133-135	3
α-helix	136-153	18
α-helix	159-176	18
α-helix	183-195	13
α-helix	203-205	3
β-strand	210-213	4	15
α-helix	220-235	16
α-helix	236-238	3
β-strand	243-246	4	15
β-strand	258-259	2	16
β-strand	263	1	15
β-strand	267	1	17
β-strand	269-271	3	18
β-strand	277-279	3	18
α-helix	281-283	3
α-helix	284-292	9
α-helix	295-297	3
α-helix	303	1
β-strand	304	1	17
α-helix	305-306	2
β-strand	307-310	4	16
α-helix	314-316	3
β-strand	317-319	3	16
α-helix	323-325	3
β-strand	328-331	4	19
α-helix	337-342	6
β-strand	344-347	4	19
β-strand	351-352	2	15
β-strand	356-359	4	20
β-strand	362-364	3	20
β-strand	369-370	2	15
β-strand	374	1	21
α-helix	375-376	2
α-helix	377-382	6
α-helix	383-384	2
α-helix	392-398	7
α-helix	406-408	3
α-helix	410-428	19
β-strand	434	1	21
α-helix	436-453	18
α-helix	461-464	4
α-helix	470-472	3
α-helix	474-477	4
β-strand	478	1	13
β-strand	482	1	3
β-strand	488-490	3	20
β-strand	491	1	14
α-helix	495-498	4
α-helix	499-501	3

Chain D: 30 helices, 27 β-strands

Element	Residues	Length	Sheet
β-strand	85-88	4	33
β-strand	89	1	34
β-strand	95-98	4	33
α-helix	100-102	3
β-strand	115	1	32
α-helix	123-125	3
β-strand	126	1	35
α-helix	133-135	3
α-helix	136-153	18
α-helix	159-176	18
α-helix	183-195	13
α-helix	203-205	3
β-strand	210-213	4	36
α-helix	220-235	16
α-helix	236-238	3
β-strand	243-246	4	36
β-strand	258-259	2	37
β-strand	263	1	36
β-strand	267	1	38
β-strand	269-271	3	39
β-strand	277-279	3	39
α-helix	281-283	3
α-helix	284-292	9
α-helix	295-297	3
α-helix	303	1
β-strand	304	1	38
α-helix	305-306	2
β-strand	307-310	4	37
α-helix	314-316	3
β-strand	317-319	3	37
α-helix	320-322	3
α-helix	323-325	3
β-strand	328-330	3	40
α-helix	339-342	4
β-strand	345-347	3	40
β-strand	351-352	2	36
β-strand	356-359	4	41
β-strand	362-364	3	41
β-strand	369-370	2	36
β-strand	374	1	42
α-helix	375-376	2
α-helix	377-382	6
α-helix	383-384	2
α-helix	392-398	7
α-helix	406-408	3
α-helix	410-428	19
β-strand	434	1	42
α-helix	436-453	18
α-helix	461-464	4
α-helix	470-472	3
α-helix	474-477	4
β-strand	478	1	34
β-strand	482	1	24
β-strand	488-490	3	41
β-strand	491	1	35
α-helix	495-498	4
α-helix	499-501	3

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Protein (nitric oxide synthase)	A, B, C, D	protein	431	Homo sapiens	P35228 (AlphaFold model)

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

>2NSI_1 PROTEIN (NITRIC OXIDE SYNTHASE) (chains A, B, C, D)
LDATPLSSPRHVRIKNWGSGMTFQDTLHHKAKGILTCRSKSCLGSIMTPKSLTRGPRDKP
TPPDELLPQAIEFVNQYYGSFKEAKIEEHLARVEAVTKEIETTGTYQLTGDELIFATKQA
WRNAPRCIGRIQWSNLQVFDARSCSTAREMFEHICRHVRYSTNNGNIRSAITVFPQRSDG
KHDFRVWNAQLIRYAGYQMPDGSIRGDPANVEFTQLCIDLGWKPKYGRFDVVPLVLQANG
RDPELFEIPPDLVLEVAMEHPKYEWFRELELKWYALPAVANMLLEVGGLEFPGCPFNGWY
MGTEIGVRDFCDVQRYNILEEVGRRMGLETHKLASLWKDQAVVEINIAVLHSFQKQNVTI
MDHHSAAESFMKYMQNEYRSRGGCPADWIWLVPPMSGSITPVFHQEMLNYVLSPFYYYQV
EAWKTHVWQDE

Ligands and cofactors

ID	Name	Formula	Copies
HEM	Protoporphyrin IX containing FE	C34 H32 Fe N4 O4	4
ITU	Ethylisothiourea	C3 H8 N2 S	4
H4B	5,6,7,8-tetrahydrobiopterin	C9 H15 N5 O3	4

Water and common crystallization additives (SO4) are not listed.

Primary citation

Crystal structures of zinc-free and -bound heme domain of human inducible nitric-oxide synthase. Implications for dimer stability and comparison with endothelial nitric-oxide synthase. Li, H., Raman, C.S., Glaser, C.B. et al. J Biol Chem (1999) 274:21276-21284. DOI 10.1074/jbc.274.30.21276 · PubMed

Other PDB entries of the same protein (UniProt P35228 (AlphaFold model), which also has an AlphaFold model), best resolution first:

6JWM 1.23 Å, Crystal structure of the SPRY domain of SPSB2 in complex with cR7, a potent cyclic…
6KEY 1.24 Å, Structural basis for the regulation of inducible nitric oxide synthase (iNOS) by the…
5XN3 1.34 Å, Crystal structure of SPSB2 in complex with a rational designed RGD containing cyclic…
6JWN 1.61 Å, Crystal structure of the SPRY domain of SPSB2 in complex with cR9, a cyclic peptide…
3E7G 2.2 Å, Structure of human INOSOX with inhibitor AR-C95791
4NOS 2.25 Å, Human inducible nitric oxide synthase with inhibitor
3HR4 2.5 Å, Human iNOS Reductase and Calmodulin Complex
1NSI 2.55 Å, Human inducible nitric oxide synthase, ZN-bound, L-arg complex
3EJ8 2.55 Å, Structure of double mutant of human iNOS oxygenase domain with bound immidazole
4CX7 3.16 Å, Structure of human iNOS heme domain in complex with (R)-6-(3-AMINO-2-(5-(2-(6-AMINO-4-…
2LL6 Solution NMR structure of CaM bound to iNOS CaM binding domain peptide
5TP6 Solution structure of the CaM34 with the iNOS CaM binding domain peptide

Browse structure collections

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