Involved in the biosynthesis of oxygen-containing labdane-type diterpenes that may be implicated in direct and indirect defense mechanisms. No activity with geranyl diphosphate or farnesyl diphosphate as substrate. Cistus creticus subsp. creticus (taxid: 483148) EC: 4EC: .EC: 2EC: .EC: 1EC: .EC: 1EC: 3EC: 3
Catalyzes the initial cyclization step in the biosynthesis of ginkgolides, a structurally unique family of diterpenoids that are highly specific platelet-activating-factor receptor antagonists. Bifunctional enzyme that catalyzes two sequential cyclizations of geranylgeranyl diphosphate (GGPP) to levopimaradiene.
Score = 99.4 bits (246), Expect = 7e-21, Method: Composition-based stats.
Identities = 47/81 (58%), Positives = 56/81 (69%), Gaps = 2/81 (2%)
Query: 2 IKLMLGSMGDGELGISAYDTAWVALIKNIDGSDINAPQFPSCLKWIADNQLPHGSWGDDK 61
IK M SMG GE SAYDTAWVA I +DGS+ PQFP L+WI NQL GSWG++
Sbjct: 104 IKNMFRSMGYGETNPSAYDTAWVARIPAVDGSE--KPQFPETLEWILQNQLKDGSWGEEF 161
Query: 62 VFLAHDRLINTLACIVALKSW 82
FLA+DR++ TLACI+ L W
Sbjct: 162 YFLAYDRILATLACIITLTIW 182
Involved in defensive oleoresin formation in conifers in response to insect attack or other injury. Involved in diterpene (C20) olefins biosynthesis. Bifunctional enzyme that catalyzes two sequential cyclizations of geranylgeranyl diphosphate (GGPP) to levopimaradiene. Levopimaradiene is the major products of the enzyme followed by abietadiene, neoabietadiene and palustradiene. No activity with geranyl diphosphate (GPP) or farnesyl diphosphate (FPP) as substrate.
Pinus taeda (taxid: 3352)
EC: 5
EC: .
EC: 5
EC: .
EC: 1
EC: .
EC: 1
EC: 2
Close Homologs in the Non-Redundant Database Detected by BLAST
; InterPro: IPR001330 The beta subunit of the farnesyltransferases is responsible for peptide binding. Squalene-hopene cyclase is a bacterial enzyme that catalyzes the cyclization of squalene into hopene, a key step in hopanoid (triterpenoid) metabolism []. Lanosterol synthase (5.4.99.7 from EC) (oxidosqualene-lanosterol cyclase) catalyzes the cyclization of (S)-2,3-epoxysqualene to lanosterol, the initial precursor of cholesterol, steroid hormones and vitamin D in vertebrates and of ergosterol in fungi []. Cycloartenol synthase () (2,3-epoxysqualene-cycloartenol cyclase) is a plant enzyme that catalyzes the cyclization of (S)-2,3-epoxysqualene to cycloartenol.; GO: 0003824 catalytic activity; PDB: 2IEJ_B 1LD7_B 1LD8_B 2H6G_B 1TN6_B 1S63_B 1MZC_B 2H6I_B 2H6F_B 1JCQ_B ....
This model identifies 2,3-oxidosqualene cyclases from Stigmatella aurantiaca which produces cycloartenol, and Gemmata obscuriglobus and Methylococcus capsulatus which each produce the closely related sterol, lanosterol.
SHC is an essential prokaryotic gene in hopanoid (triterpenoid) biosynthesis. Squalene hopene cyclase, an integral membrane protein, directly cyclizes squalene into hopanoid products.
>cd02897 A2M_2 Proteins similar to alpha2-macroglobulin (alpha (2)-M)
This group also contains the pregnancy zone protein (PZP). Alpha(2)-M and PZP are broadly specific proteinase inhibitors. Alpha (2)-M is a major carrier protein in serum. The structural thioester of alpha (2)-M, is involved in the immobilization and entrapment of proteases. PZP is a trace protein in the plasma of non-pregnant females and males which is elevated in pregnancy. Alpha (2)-M and PZ bind to placental protein-14 and may modulate its activity in T-cell growth and cytokine production contributing to fetal survival. It has been suggested that thioester bond cleavage promotes the binding of PZ and alpha (2)-M to the CD91 receptor clearing them from circulation.
>cd02889 SQCY Squalene cyclase (SQCY) domain; found in class II terpene cyclases that have an alpha 6 - alpha 6 barrel fold
Squalene cyclase (SQCY) and 2,3-oxidosqualene cyclase (OSQCY) are integral membrane proteins that catalyze a cationic cyclization cascade converting linear triterpenes to fused ring compounds. Bacterial SQCY catalyzes the convertion of squalene to hopene or diplopterol. Eukaryotic OSQCY transforms the 2,3-epoxide of squalene to compounds such as, lanosterol (a metabolic precursor of cholesterol and steroid hormones) in mammals and fungi or, cycloartenol in plants. Deletion of a single glycine residue of Alicyclobacillus acidocaldarius SQCY alters its substrate specificity into that of eukaryotic OSQCY. Both enzymes have a second minor domain, which forms an alpha-alpha barrel that is inserted into the major domain. This group also contains SQCY-like archael sequences and some bacterial SQCY's which lack this minor domain.
>cd00688 ISOPREN_C2_like This group contains class II terpene cyclases, protein prenyltransferases beta subunit, two broadly specific proteinase inhibitors alpha2-macroglobulin (alpha (2)-M) and pregnancy zone protein (PZP) and, the C3 C4 and C5 components of vertebrate complement
Class II terpene cyclases include squalene cyclase (SQCY) and 2,3-oxidosqualene cyclase (OSQCY), these integral membrane proteins catalyze a cationic cyclization cascade converting linear triterpenes to fused ring compounds. The protein prenyltransferases include protein farnesyltransferase (FTase) and geranylgeranyltransferase types I and II (GGTase-I and GGTase-II) which catalyze the carboxyl-terminal lipidation of Ras, Rab, and several other cellular signal transduction proteins, facilitating membrane associations and specific protein-protein interactions. Alpha (2)-M is a major carrier protein in serum and involved in the immobilization and entrapment of proteases. PZP is a pregnancy associated protein.
>cd02889 SQCY Squalene cyclase (SQCY) domain; found in class II terpene cyclases that have an alpha 6 - alpha 6 barrel fold
Squalene cyclase (SQCY) and 2,3-oxidosqualene cyclase (OSQCY) are integral membrane proteins that catalyze a cationic cyclization cascade converting linear triterpenes to fused ring compounds. Bacterial SQCY catalyzes the convertion of squalene to hopene or diplopterol. Eukaryotic OSQCY transforms the 2,3-epoxide of squalene to compounds such as, lanosterol (a metabolic precursor of cholesterol and steroid hormones) in mammals and fungi or, cycloartenol in plants. Deletion of a single glycine residue of Alicyclobacillus acidocaldarius SQCY alters its substrate specificity into that of eukaryotic OSQCY. Both enzymes have a second minor domain, which forms an alpha-alpha barrel that is inserted into the major domain. This group also contains SQCY-like archael sequences and some bacterial SQCY's which lack this minor domain.
>cd02896 complement_C3_C4_C5 Proteins similar to C3, C4 and C5 of vertebrate complement
The vertebrate complement system, comprised of a large number of distinct plasma proteins, is an effector of both the acquired and innate immune systems. The point of convergence of the classical, alternative and lectin pathways of the complement system is the proteolytic activation of C3. C4 plays a key role in propagating the classical and lectin pathways. C5 participates in the classical and alternative pathways. The thioester bond located within the structure of C3 and C4 is central to the function of complement. C5 does not contain an active thioester bond.
>cd00688 ISOPREN_C2_like This group contains class II terpene cyclases, protein prenyltransferases beta subunit, two broadly specific proteinase inhibitors alpha2-macroglobulin (alpha (2)-M) and pregnancy zone protein (PZP) and, the C3 C4 and C5 components of vertebrate complement
Class II terpene cyclases include squalene cyclase (SQCY) and 2,3-oxidosqualene cyclase (OSQCY), these integral membrane proteins catalyze a cationic cyclization cascade converting linear triterpenes to fused ring compounds. The protein prenyltransferases include protein farnesyltransferase (FTase) and geranylgeranyltransferase types I and II (GGTase-I and GGTase-II) which catalyze the carboxyl-terminal lipidation of Ras, Rab, and several other cellular signal transduction proteins, facilitating membrane associations and specific protein-protein interactions. Alpha (2)-M is a major carrier protein in serum and involved in the immobilization and entrapment of proteases. PZP is a pregnancy associated protein.
>cd02891 A2M_like Proteins similar to alpha2-macroglobulin (alpha (2)-M)
Alpha (2)-M is a major carrier protein in serum. It is a broadly specific proteinase inhibitor. The structural thioester of alpha (2)-M, is involved in the immobilization and entrapment of proteases. This group contains another broadly specific proteinase inhibitor: pregnancy zone protein (PZP). PZP is a trace protein in the plasma of non-pregnant females and males which is elevated in pregnancy. Alpha (2)-M and PZ bind to placental protein-14 and may modulate its activity in T-cell growth and cytokine production thereby protecting the allogeneic fetus from attack by the maternal immune system. This group also contains C3, C4 and C5 of vertebrate complement. The vertebrate complement is an effector of both the acquired and innate immune systems The point of convergence of the classical, alternative and lectin pathways of the complement system is the proteolytic activation of C3. C4 plays a key role in propaga
>cd02892 SQCY_1 Squalene cyclase (SQCY) domain subgroup 1; found in class II terpene cyclases that have an alpha 6 - alpha 6 barrel fold
Squalene cyclase (SQCY) and 2,3-oxidosqualene cyclase (OSQCY) are integral membrane proteins that catalyze a cationic cyclization cascade converting linear triterpenes to fused ring compounds. This group contains bacterial SQCY which catalyzes the convertion of squalene to hopene or diplopterol and eukaryotic OSQCY which transforms the 2,3-epoxide of squalene to compounds such as, lanosterol in mammals and fungi or, cycloartenol in plants. Deletion of a single glycine residue of Alicyclobacillus acidocaldarius SQCY alters its substrate specificity into that of eukaryotic OSQCY. Both enzymes have a second minor domain, which forms an alpha-alpha barrel that is inserted into the major domain.
This family of enzymes catalyzes the cyclization of the triterpenes squalene or 2-3-oxidosqualene to a variety of products including hopene, lanosterol, cycloartenol, amyrin, lupeol and isomultiflorenol.
This model identifies 2,3-oxidosqualene cyclases from Stigmatella aurantiaca which produces cycloartenol, and Gemmata obscuriglobus and Methylococcus capsulatus which each produce the closely related sterol, lanosterol.
>PF07678 A2M_comp: A-macroglobulin complement component; InterPro: IPR011626 This domain covers the complement component region of the alpha-2-macroglobulin family
The alpha-macroglobulin (aM) family of proteins includes protease inhibitors [], typified by the human tetrameric a2-macroglobulin (a2M); they belong to the MEROPS proteinase inhibitor family I39, clan IL. These protease inhibitors share several defining properties, which include (i) the ability to inhibit proteases from all catalytic classes, (ii) the presence of a 'bait region' and a thiol ester, (iii) a similar protease inhibitory mechanism and (iv) the inactivation of the inhibitory capacity by reaction of the thiol ester with small primary amines. aM protease inhibitors inhibit by steric hindrance []. The mechanism involves protease cleavage of the bait region, a segment of the aM that is particularly susceptible to proteolytic cleavage, which initiates a conformational change such that the aM collapses about the protease. In the resulting aM-protease complex, the active site of the protease is sterically shielded, thus substantially decreasing access to protein substrates. Two additional events occur as a consequence of bait region cleavage, namely (i) the h-cysteinyl-g-glutamyl thiol ester becomes highly reactive and (ii) a major conformational change exposes a conserved COOH-terminal receptor binding domain [] (RBD). RBD exposure allows the aM protease complex to bind to clearance receptors and be removed from circulation []. Tetrameric, dimeric, and, more recently, monomeric aM protease inhibitors have been identified [, ].; GO: 0005615 extracellular space; PDB: 1QSJ_D 1QQF_A 4ACQ_C 2B39_B 2WIN_H 2I07_B 2ICF_B 2XWJ_D 3G6J_B 2NOJ_C ....
This group also contains the pregnancy zone protein (PZP). Alpha(2)-M and PZP are broadly specific proteinase inhibitors. Alpha (2)-M is a major carrier protein in serum. The structural thioester of alpha (2)-M, is involved in the immobilization and entrapment of proteases. PZP is a trace protein in the plasma of non-pregnant females and males which is elevated in pregnancy. Alpha (2)-M and PZ bind to placental protein-14 and may modulate its activity in T-cell growth and cytokine production contributing to fetal survival. It has been suggested that thioester bond cleavage promotes the binding of PZ and alpha (2)-M to the CD91 receptor clearing them from circulation.
This family of enzymes catalyzes the cyclization of the triterpenes squalene or 2-3-oxidosqualene to a variety of products including hopene, lanosterol, cycloartenol, amyrin, lupeol and isomultiflorenol.
SHC is an essential prokaryotic gene in hopanoid (triterpenoid) biosynthesis. Squalene hopene cyclase, an integral membrane protein, directly cyclizes squalene into hopanoid products.
>cd02892 SQCY_1 Squalene cyclase (SQCY) domain subgroup 1; found in class II terpene cyclases that have an alpha 6 - alpha 6 barrel fold
Squalene cyclase (SQCY) and 2,3-oxidosqualene cyclase (OSQCY) are integral membrane proteins that catalyze a cationic cyclization cascade converting linear triterpenes to fused ring compounds. This group contains bacterial SQCY which catalyzes the convertion of squalene to hopene or diplopterol and eukaryotic OSQCY which transforms the 2,3-epoxide of squalene to compounds such as, lanosterol in mammals and fungi or, cycloartenol in plants. Deletion of a single glycine residue of Alicyclobacillus acidocaldarius SQCY alters its substrate specificity into that of eukaryotic OSQCY. Both enzymes have a second minor domain, which forms an alpha-alpha barrel that is inserted into the major domain.
The protein prenyltransferase family of lipid-modifying enzymes includes protein farnesyltransferase (FTase) and geranylgeranyltransferase types I and II (GGTase-I and GGTase-II). They catalyze the carboxyl-terminal lipidation of Ras, Rab, and several other cellular signal transduction proteins, facilitating membrane associations and specific protein-protein interactions. Prenyltransferases employ a Zn2+ ion to alkylate a thiol group catalyzing the formation of thioether linkages between the C1 atom of farnesyl (15-carbon by FTase) or geranylgeranyl (20-carbon by GGTase-I, II) isoprenoid lipids and cysteine residues at or near the C-terminus of protein acceptors. FTase and GGTase-I prenylate the cysteine in the terminal sequence, "CAAX"; and GGTase-II prenylates both cysteines in the "CC" (or "CXC") terminal sequence. These enzymes are heterodimeric with both alpha and beta subunits re
The protein prenyltransferase family of lipid-modifying enzymes includes protein farnesyltransferase (FTase) and geranylgeranyltransferase types I and II (GGTase-I and GGTase-II). They catalyze the carboxyl-terminal lipidation of Ras, Rab, and several other cellular signal transduction proteins, facilitating membrane associations and specific protein-protein interactions. Prenyltransferases employ a Zn2+ ion to alkylate a thiol group catalyzing the formation of thioether linkages between the C1 atom of farnesyl (15-carbon by FTase) or geranylgeranyl (20-carbon by GGTase-I, II) isoprenoid lipids and cysteine residues at or near the C-terminus of protein acceptors. FTase and GGTase-I prenylate the cysteine in the terminal sequence, "CAAX"; and GGTase-II prenylates both cysteines in the "CC" (or "CXC") terminal sequence. These enzymes are heterodimeric with both alpha and beta subunits re
>cd02894 GGTase-II Geranylgeranyltransferase type II (GGTase-II)_like proteins containing the protein prenyltransferase (PTase) domain, beta subunit (alpha 6 - alpha 6 barrel fold)
GGTase-IIs are a subgroup of the protein prenyltransferase family of lipid-modifying enzymes. PTases catalyze the carboxyl-terminal lipidation of Ras, Rab, and several other cellular signal transduction proteins, facilitating membrane associations and specific protein-protein interactions. Prenyltransferases employ a Zn2+ ion to alkylate a thiol group catalyzing the formation of thioether linkages between cysteine residues at or near the C-terminus of protein acceptors and the C1 atom of isoprenoid lipids (geranylgeranyl (20-carbon) in the case of GGTase-II ). GGTase-II catalyzes alkylation of both cysteine residues in Rab proteins containing carboxy-terminal "CC", "CXCX" or "CXC" motifs. PTases are heterodimeric with both alpha and beta subunits required for catalytic activity. In contrast to other prenyltr
>cd02893 FTase Protein farnesyltransferase (FTase)_like proteins containing the protein prenyltransferase (PTase) domain, beta subunit (alpha 6 - alpha 6 barrel fold)
FTases are a subgroup of PTase family of lipid-modifying enzymes. PTases catalyze the carboxyl-terminal lipidation of Ras, Rab, and several other cellular signal transduction proteins, facilitating membrane associations and specific protein-protein interactions. These proteins are heterodimers of alpha and beta subunits. Both subunits are required for catalytic activity. Prenyltransferases employ a Zn2+ ion to alkylate a thiol group catalyzing the formation of thioether linkages between cysteine residues at or near the C-terminus of protein acceptors and the C1 atom of isoprenoid lipids. Ftase attaches a 15-carbon farnesyl group to the cysteine within the C-terminal CaaX motif of substrate proteins when X is Ala, Met, Ser, Cys or Gln. Protein farnesylation has been shown to play critical roles in a variety of cellular pro
>cd02891 A2M_like Proteins similar to alpha2-macroglobulin (alpha (2)-M)
Alpha (2)-M is a major carrier protein in serum. It is a broadly specific proteinase inhibitor. The structural thioester of alpha (2)-M, is involved in the immobilization and entrapment of proteases. This group contains another broadly specific proteinase inhibitor: pregnancy zone protein (PZP). PZP is a trace protein in the plasma of non-pregnant females and males which is elevated in pregnancy. Alpha (2)-M and PZ bind to placental protein-14 and may modulate its activity in T-cell growth and cytokine production thereby protecting the allogeneic fetus from attack by the maternal immune system. This group also contains C3, C4 and C5 of vertebrate complement. The vertebrate complement is an effector of both the acquired and innate immune systems The point of convergence of the classical, alternative and lectin pathways of the complement system is the proteolytic activation of C3. C4 plays a key role in propaga
>cd02894 GGTase-II Geranylgeranyltransferase type II (GGTase-II)_like proteins containing the protein prenyltransferase (PTase) domain, beta subunit (alpha 6 - alpha 6 barrel fold)
GGTase-IIs are a subgroup of the protein prenyltransferase family of lipid-modifying enzymes. PTases catalyze the carboxyl-terminal lipidation of Ras, Rab, and several other cellular signal transduction proteins, facilitating membrane associations and specific protein-protein interactions. Prenyltransferases employ a Zn2+ ion to alkylate a thiol group catalyzing the formation of thioether linkages between cysteine residues at or near the C-terminus of protein acceptors and the C1 atom of isoprenoid lipids (geranylgeranyl (20-carbon) in the case of GGTase-II ). GGTase-II catalyzes alkylation of both cysteine residues in Rab proteins containing carboxy-terminal "CC", "CXCX" or "CXC" motifs. PTases are heterodimeric with both alpha and beta subunits required for catalytic activity. In contrast to other prenyltr
>PF07678 A2M_comp: A-macroglobulin complement component; InterPro: IPR011626 This domain covers the complement component region of the alpha-2-macroglobulin family
The alpha-macroglobulin (aM) family of proteins includes protease inhibitors [], typified by the human tetrameric a2-macroglobulin (a2M); they belong to the MEROPS proteinase inhibitor family I39, clan IL. These protease inhibitors share several defining properties, which include (i) the ability to inhibit proteases from all catalytic classes, (ii) the presence of a 'bait region' and a thiol ester, (iii) a similar protease inhibitory mechanism and (iv) the inactivation of the inhibitory capacity by reaction of the thiol ester with small primary amines. aM protease inhibitors inhibit by steric hindrance []. The mechanism involves protease cleavage of the bait region, a segment of the aM that is particularly susceptible to proteolytic cleavage, which initiates a conformational change such that the aM collapses about the protease. In the resulting aM-protease complex, the active site of the protease is sterically shielded, thus substantially decreasing access to protein substrates. Two additional events occur as a consequence of bait region cleavage, namely (i) the h-cysteinyl-g-glutamyl thiol ester becomes highly reactive and (ii) a major conformational change exposes a conserved COOH-terminal receptor binding domain [] (RBD). RBD exposure allows the aM protease complex to bind to clearance receptors and be removed from circulation []. Tetrameric, dimeric, and, more recently, monomeric aM protease inhibitors have been identified [, ].; GO: 0005615 extracellular space; PDB: 1QSJ_D 1QQF_A 4ACQ_C 2B39_B 2WIN_H 2I07_B 2ICF_B 2XWJ_D 3G6J_B 2NOJ_C ....
>TIGR02474 pec_lyase pectate lyase, PelA/Pel-15E family
Members of this family are isozymes of pectate lyase (EC 4.2.2.2), also called polygalacturonic transeliminase and alpha-1,4-D-endopolygalacturonic acid lyase.
>cd02896 complement_C3_C4_C5 Proteins similar to C3, C4 and C5 of vertebrate complement
The vertebrate complement system, comprised of a large number of distinct plasma proteins, is an effector of both the acquired and innate immune systems. The point of convergence of the classical, alternative and lectin pathways of the complement system is the proteolytic activation of C3. C4 plays a key role in propagating the classical and lectin pathways. C5 participates in the classical and alternative pathways. The thioester bond located within the structure of C3 and C4 is central to the function of complement. C5 does not contain an active thioester bond.
>KOG0497 consensus Oxidosqualene-lanosterol cyclase and related proteins [Lipid transport and metabolism]
Crystal Structure Of Taxadiene Synthase From Pacifi
5e-17
>pdb|3PYA|A Chain A, Crystal Structure Of Ent-Copalyl Diphosphate Synthase From Arabidopsis Thaliana In Complex With (S)-15-Aza-14,15-Dihydrogeranylgeranyl Thiolodiphosphate Length = 727
>pdb|3P5P|A Chain A, Crystal Structure Of Taxadiene Synthase From Pacific Yew (Taxus Brevifolia) In Complex With Mg2+ And 13-Aza-13,14-Dihydrocopalyl Diphosphate Length = 764
>3pya_A ENT-copalyl diphosphate synthase, chloroplastic; class I and II terpene cyclase fold, class II diterpene CYCL DXXDD motif; HET: AG8 1PE; 2.25A {Arabidopsis thaliana} PDB: 3pyb_A* Length = 727
>3pya_A ENT-copalyl diphosphate synthase, chloroplastic; class I and II terpene cyclase fold, class II diterpene CYCL DXXDD motif; HET: AG8 1PE; 2.25A {Arabidopsis thaliana} PDB: 3pyb_A*
>2pmv_A Gastric intrinsic factor; cobalamin transport protein alpha6-alpha6 motif two domain P transport protein; HET: NAG B12; 2.60A {Homo sapiens} PDB: 3kq4_A*
