Reviewed, UniProtKB/Swiss-Prot P00947 (SDIS_COMTE)

Names and origin

Protein names

Recommended name:
    Steroid Delta-isomerase
    EC=5.3.3.1
Alternative name(s):
    Delta(5)-3-ketosteroid isomerase

Gene names

Name:

ksi

Organism

Comamonas testosteroni (Pseudomonas testosteroni)

Taxonomic identifier

285 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Betaproteobacteria › Burkholderiales › Comamonadaceae › Comamonas

Protein attributes

Sequence length	125 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level.

General annotation (Comments)

Catalytic activity	A 3-oxo-Delta(5)-steroid = a 3-oxo-Delta(4)-steroid.
Subunit structure	Homodimer.
Induction	By steroids.

Ontologies

Keywords
Biological process	Lipid metabolism Steroid metabolism
Molecular function	Isomerase
Technical term	3D-structure Direct protein sequencing
Gene Ontology (GO)
Biological process	steroid metabolic process Inferred from electronic annotation. Source: UniProtKB-KW transport Inferred from electronic annotation. Source: InterPro
Cellular component	intracellular Inferred from electronic annotation. Source: InterPro
Molecular function	steroid delta-isomerase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 125

125

Steroid Delta-isomerase

PRO_0000097644

Sites

Active site

14

1

Proton donor

Active site

38

1

Proton acceptor Ref.2

Binding site

99

1

Substrate

Experimental info

Mutagenesis

39

1

P → A: Perturbs active site geometry and lowers activity.

Mutagenesis

99

1

D → A: Lowers activity 3000-fold. Ref.6

Mutagenesis

116

1

F → W: Slightly lower activity at neutral pH. Increased catalytic activity at pH 3.8.

Secondary structure

1

.

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125

Helix Strand Turn

Details...

Helix

4 – 20

17

Helix

23 – 27

5

Beta strand

30 – 39

10

Beta strand

45 – 47

3

Helix

48 – 58

11

Beta strand

64 – 67

4

Beta strand

72 – 74

3

Beta strand

77 – 87

11

Beta strand

92 – 95

4

Beta strand

98 – 103

6

Beta strand

109 – 115

7

Helix

118 – 120

3

Beta strand

121 – 123

3

Sequences

	Sequence		Length	Mass (Da)
	P00947-1 [UniParc]. Last modified February 1, 1991. Version 2. Checksum: 2ECD410D4B929430	FASTA	125	13,398
	10 20 30 40 50 60 MNTPEHMTAV VQRYVAALNA GDLDGIVALF ADDATVEDPV GSEPRSGTAA IREFYANSLK 70 80 90 100 110 120 LPLAVELTQE VRAVANEAAF AFTVSFEYQG RKTVVAPIDH FRFNGAGKVV SMRALFGEKN IHAGA

References

[1]	"Nucleotide sequence of the gene for the delta 5-3-ketosteroid isomerase of Pseudomonas testosteroni." Choi K.Y., Benisek W.F. Gene 69:121-129(1988) [PubMed: 3224818] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Isolation and sequencing of the gene encoding delta 5-3-ketosteroid isomerase of Pseudomonas testosteroni: overexpression of the protein." Kuliopulos A., Shortle D., Talalay P. Proc. Natl. Acad. Sci. U.S.A. 84:8893-8897(1987) [PubMed: 3480517] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[3]	"The amino acid sequence of delta 5-3-ketosteroid isomerase of Pseudomonas testosteroni." Benson A.M., Jarabak R., Talalay P. J. Biol. Chem. 246:7514-7525(1971) [PubMed: 5135313] [Abstract] Cited for: PRELIMINARY PROTEIN SEQUENCE.
[4]	"Molecular weight determination and structural studies of Pseudomonas testosteroni delta 5 leads to 4-3-oxosteroid isomerase (EC 5.3.3.1)." Weintraub H., Vincent F., Baulieu E.-E., Alfsen A. FEBS Lett. 37:82-88(1973) [PubMed: 4753764] [Abstract] Cited for: CHARACTERIZATION.
[5]	"High-resolution crystal structures of delta5-3-ketosteroid isomerase with and without a reaction intermediate analogue." Kim S.-W., Cha S.-S., Cho H.-S., Kim J.-S., Ha N.-C., Cho M.-J., Joo S., Kim K.-K., Choi K.-Y., Oh B.-H. Biochemistry 36:14030-14036(1997) [PubMed: 9369474] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.3 ANGSTROMS).
[6]	"Solution structure of 3-oxo-delta5-steroid isomerase." Wu Z.R., Ebrahimian S., Zawrotny M.E., Thornburg L.D., Perez-Alvarado G.C., Brothers P., Pollack R.M., Summers M.F. Science 276:415-418(1997) [PubMed: 9103200] [Abstract] Cited for: STRUCTURE BY NMR, MUTAGENESIS OF ASP-99.
[7]	"Solution structure of delta 5-3-ketosteroid isomerase complexed with the steroid 19-nortestosterone hemisuccinate." Massiah M.A., Abeygunawardana C., Gittis A.G., Mildvan A.S. Biochemistry 37:14701-14712(1998) [PubMed: 9778345] [Abstract] Cited for: STRUCTURE BY NMR IN COMPLEX WITH PRODUCT ANALOG.
[8]	"Crystal structure of delta(5)-3-ketosteroid isomerase from Pseudomonas testosteroni in complex with equilenin settles the correct hydrogen bonding scheme for transition state stabilization." Cho H.-S., Ha N.-C., Choi G., Kim H.-J., Lee D., Oh K.S., Kim K.S., Lee W., Choi K.Y., Oh B.-H. J. Biol. Chem. 274:32863-32868(1999) [PubMed: 10551849] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.3 ANGSTROMS) IN COMPLEX WITH REACTION INTERMEDIATE ANALOG.
[9]	"The conserved cis-Pro39 residue plays a crucial role in the proper positioning of the catalytic base Asp38 in ketosteroid isomerase from Comamonas testosteroni." Nam G.H., Cha S.-S., Yun Y.S., Oh Y.H., Hong B.H., Lee H.-S., Choi K.-Y. Biochem. J. 375:297-305(2003) [PubMed: 12852789] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.3 ANGSTROMS) OF MUTANT ALA-39 IN COMPLEX WITH REACTION INTERMEDIATE ANALOG.
[10]	"Origin of the different pH activity profile in two homologous ketosteroid isomerases." Yun Y.S., Lee T.-H., Nam G.H., Jang do S., Shin S., Oh B.-H., Choi K.-Y. J. Biol. Chem. 278:28229-28236(2003) [PubMed: 12734184] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS) OF MUTANT TRP-116.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

M22749 Genomic DNA. Translation: AAA25872.1.
J03568 Genomic DNA. Translation: AAA25871.1.

PIR

SIPSDT. JT0336.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1BUQ	NMR	-	A/B	1-125	[»]
1ISK	NMR	-	A/B	1-125	[»]
1OCV	X-ray	2.00	A/B/C/D	1-125	[»]
1OGZ	X-ray	2.30	A	1-125	[»]
1OHP	X-ray	1.53	A/B/C/D	1-125	[»]
1OHS	X-ray	1.70	A/B/C/D	1-125	[»]
1QJG	X-ray	2.30	A/B/C/D/E/F	1-125	[»]
8CHO	X-ray	2.30	A	1-125	[»]

ModBase

Search...

Enzyme and pathway databases

BRENDA

5.3.3.1. 4566.

Family and domain databases

InterPro

IPR002075. NTF2.
IPR011944. Steroid_delta5-4_isomerase.
[Graphical view]

Pfam

PF02136. NTF2. 1 hit.
[Graphical view]

TIGRFAMs

TIGR02246. CHP2246. 1 hit.

ProtoNet

Search...

Entry information

Entry name

SDIS_COMTE

Accession

Primary (citable) accession number: P00947

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	February 1, 1991
Last modified:	February 9, 2010
This is version 74 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)