PHOSPHOLIPASES

ENZYMES

SE-100
Diacylglycerol kinase (from E. coli)
sn-1,2-diacylglycerol kinase (DAGK)
A highly useful tool to quantify diacylglycerols, the product of phospholipase C hydrolysis of membrane lipids.

SE-104
Phospholipase A₂ (from Apis mellifera)
Phosphatidylcholine 2-acylhydrolase
[9001-84-7] (EC 3.1.1.4) Storage: -20°C
Supplied lyophilized. Specific activity: 600-1800 U/mg protein. One unit will hydrolyze 1 µmol soybean L-a-phosphatidylcholine to L-a-lysophosphatidylcholine and fatty acid per minute at pH 8.9 and 25°C. Also acts on phosphatidylethanolamine and other phosphatidyl esters.
1 mg
5 mg

SE-106
Phospholipase C, phosphatidylinositol-specific (from Bacillus cereus)
>95% by SDS-PAGE [9001-86-9] (EC 3.1.4.10) Storage: -20°C
Supplied at 0.1 mg/ml. Specific activity: ~500 U/mg protein. One unit will liberate 4 U of glycosyl-PI-anchored acetylcholinesterase per minute at pH 7.4 and 37°C. May be used to release phosphatidylinositol (PI)-linked proteins from membranes.
5 U
5 x 5 U

SE-166
Phospholipase D (from Streptomyces sp.)
Phosphatidylcholine phosphatidohydrolase
>90% by SDS-PAGE, 50-55 kDa, [9001-87-0] (EC 3.1.4.4) Storage: -70°C
Supplied ~5000 U/ml in 100 mM sodium acetate, pH 5.6. Specific activity: 20 kU/mg protein. One unit will release 1 µmol of choline from L-a-phosphatidylcholine per hour at pH 5.6 and 37°C^1,2. This enzyme has two useful activities: 1) Hydrolysis of lecithins to phosphatidic acid and choline. Also active on phosphatidylserine, phosphatidylethanolamine, phosphatidylglycerol and sphingomyelins. 2) Transfer of n-alchohols, in the presence of phosphatidylcholine, to produce phosphatidyl alcohols and choline.
2.5 kU
5 x 2.5 kU

SE-108
Sphingomyelinase (from Staphylococcus aureus)
Sphingomyelin cholinephosphohydrolase
[9031-54-3] (EC 3.1.4.12) Storage: 4°C
Supplied in 50% glycerol/0.25 M phosphate buffer. Specific activity: 100-300 U/mg protein. One unit will hydrolyze 1 µmol of TNPAL-sphingomyelin per minute at pH 7.4 and 37°C. May be used exogenously to initiate the sphingomyelin signaling pathway^3,4,5. Has very little activity on phosphatidylcholine.
10 U
50 U

PHOSPHOLIPASE A₂ (PLA₂)

PLA₂ ANTISENSE OLIGO'S

ZA-110
cPLA₂ Antisense Oligo
>90% by HPLC and capillary electrophoresis, MW=5.6 kDa, Storage: -70°C
An 18-mer oligodeoxynucleotide with four phosphorothioate linkages, directed against the human cytosolic, Ca²⁺-dependent phospholipase A₂ (cPLA₂). To increase nuclease resistance, this oligo contains a total of four phosphorothioate linkages, two each at the 5' and 3' ends. An identical oligo without phosphorothioate linkages and applied without cationic lipids decreased human monocyte cPLA₂ protein levels by 57% and chemokine-stimulated arachidonate release by 81% (10 µM)⁶. At 3-10 µM, it completely blocked chemotaxis toward monocyte chemotactic protein-1⁶. Supplied lyophilized.
25 nmols

ZA-111
cPLA₂ Control Oligo
>90% by HPLC and capillary electrophoresis, MW=5.6 kDa, Storage: -70°C
An 18-mer oligo with two phosphorothioate linkages at each end, it has the cPLA₂ antisense sequence (ZA-110, above) except for four mismatched bases. Oligonucleotide with this sequence had no effect on cPLA₂ expression or chemokine-stimulated arachidonate release⁶. Supplied lyophilized.
25 nmols

ZP-110
cPLA₂ Antisense and Control Oligo Pair
This pair consists of cPLA₂ Antisense Oligo, 25 nmols (ZA-110) and cPLA₂ Control Oligo, 25 nmols (ZA-111).
1 pair

PLA₂ INHIBITORS

ST-335
AACOCF₃
Arachidonyltrifluoromethyl ketone
98%, MW=356.5 [149301-79-1] Storage: -20°C
AACOCF₃ is a trifluoromethylketone derivative of arachidonic acid. It is a selective inhibitor of human cytosolic PLA₂ and Ca²⁺-independent PLA₂ (iPLA₂, IC₅₀=15 µM)⁸. It is active in intact platelets⁹ and U937 cells (IC₅₀=8 µM)¹⁰. It also inhibits anandamide amidase (100% at 7.5 µM)¹¹.
10 mg
50 mg

EI-178
N-(p-Amylcinnamoyl)anthranilic acid (ACA)
99%, MW=337.4 [110683-10-8] Storage: RT
ACA is a close structural analog of the PLA₂ inhibitor, ONO-RS-082¹² and possesses similar but less potent inhibitory activity¹³. It also possesses moderate leukotriene antagonist activity¹⁴.
50 mg
250 mg

EI-175
Aristolochic acid
97%, 1:1 mixture of aristolochic acids I and II, MW=341.3 [313-67-7] Storage: RT
Aristolochic acid is a phenanthrenecarboxylic acid derivative occurring in Aristolochiaceae. It has been reported to inhibit PLA₂ from various snake venoms¹⁵ as well as human platelet and synovial fluid PLA₂¹⁶. It also inhibits ionophore-stimulated PLA₂ activity in human neutrophils (IC₅₀=40 µM)¹⁷.
50 mg
250 mg

EI-176
Aristolochic acid sodium salt
97%, 1:1 mixture of aristolochic acids I and II, MW=363.2, Storage: RT
Water soluble form of aristolochic acid.
50 mg
250 mg

EI-123
Cytidine 5'-diphosphocholine sodium salt (CDP-choline)
99%, MW=510.3 [33818-15-4] Storage: 0°C
Completely inhibits PLA₂ activation following cryogenic brain injury in the rabbit at 200 mg/kg¹⁸. Intermediate in phospholipid biosynthesis.
100 mg
1 g

EI-112
7,7-Dimethyleicosadienoic acid (DEDA)
98%, MW=336.6 [89560-01-0] Storage: 0°C
DEDA inhibits P388D₁ cell PLA₂ (IC₅₀=16 µM)¹⁹ and snake venum PLA₂ (IC₅₀=14 µM)²⁰. It inhibits human recombinant sPLA₂ (IC₅₀=5.8 µM) selectively over cPLA₂. It is also a weak inhibitor of 5-lipoxygenase (IC₅₀=56 µM, RBL-l cells)²². Licensed under U.S. patent 4,434,101.
10 mg
50 mg

ST-340
HELSS (Haloenol lactone suicide substrate, BEL, Bromoenol lactone)
E-6-(Bromomethylene)tetrahydro-3-(1-naphthalenyl)-2H-pyran-2-one
98%, MW=317.2 [88070-98-8] Storage: -20°C
HELSS is a potent, irreversible, mechanism-based inhibitor of Ca²⁺-independent PLA₂ (70% inhibition at 100 nM)^23,8. It possesses a 1000-fold selectivity for Ca²⁺-independent PLA₂ vs. Ca²⁺-dependent PLA₂. It has been used to identify the PLA₂ involved in the release of arachidonate induced by vasopressin stimulation of A-10 smooth muscle cells (IC₅₀=1 µM²⁴. It has also been shown to inhibit the Mg²⁺-dependent phophatidate phosphohydrolase from P388D₁ macrophages (IC₅₀~8 µM)²⁵.
5 mg
25 mg

ST-310
Luffariellolide
98%, MW=386.3, Storage: -20°C
Luffariellolide, a marine sesterterpenoid isolated from Luffariella sp., is structurally related to manoalide. It is slightly less potent than manoalide at PLA₂ inhibition but partially reversible (IC₅₀=0.23 µM, bee venum PLA₂)²⁶. It inhibits human recombinant sPLA₂ (IC₅₀=9.3 µM) selectively over cPLA₂^21,27.
1 mg
5 x 1 mg

ST-360
Methyl arachidonyl fluorophosphonate (MAFP)
98%, MW=370.5, Storage: -20°C
MAFP is a new, selective, irreversible inhibitor of cPLA₂, IC₅₀=5 µM^28,29. It has also been shown to inhibit the Ca²⁺-independent iPLA₂ (IC₅₀=0.5 µM)³⁰.
5 mg
25 mg

EI-177
Manoalide
98%, MW=416.5 [75088-80-1] Storage: -20°C
Manoalide is a marine sesterterpenoid isolated from Luffariella variabilis. It irreversibly inhibits human synovial fluid PLA₂ (IC₅₀=0.02-0.2 µM depending on substrate)³¹ as well as bee (IC₅₀=0.05 µM)³² and cobra venum (IC₅₀=2 µM)³³ PLA₂. It inhibits human recombinant sPLA₂ (IC₅₀=4.7 µM) selectively over cPLA₂²¹. It inhibits the release of arachidonate in cultured mouse peritoneal macrophages and in a mouse in vivo model³⁴. Its mechanism of action involves covalent modification of lysine residues^35,36. Also inhibits PLC (IC₅₀=1.5 µM)³⁷ and calcium channels³⁸.
1 mg
5 x 1 mg

ST-315
3-(4-Octadecyl)-benzoylacrylic acid (OBAA)
98%, MW=428.4, Storage: RT
OBAA is a potent inhibitor of snake venom PLA₂ (IC₅₀=0.07 µM)³⁹. It inhibits allergen-induced bronchospasm in the guinea pig⁴⁰.
10 mg
50 mg

EI-118
Oleyloxyethyl phosphorylcholine
98%, MW=477.7 [96720-06-8] Storage: -20°C
A potent and specific substrate analog PLA₂ inhibitor (IC₅₀=6.2 µM-porcine pancreatic PLA₂)⁴¹. It inhibits human recombinant sPLA₂ (IC₅₀=13.7 µM) selectively over cPLA₂²¹. At 1 µM it completely blocked the myogenic response in perfused dog renal arcuate arteries⁴².
10 mg
50 mg

ST-320
ONO-RS-082
2-(p-Amylcinnamoyl)amino-4-chlorobenzoic acid
98%, MW=371.9 [99754-06-0] Storage: RT
Inhibits epinephrine-stimulated thromboxane production (86% at 3.5 µM) via inhibition of PLA₂ in human platelets¹². IC₅₀=7 µM for purified guinea pig lung PLA₂⁴³.
20 mg
100 mg

ST-336
PACOCF₃
Palmityltrifluoromethyl ketone
99%, MW=308.4 [141022-99-3] Storage: -20°C
Selective cPLA₂ (IC₅₀=45 µM)⁴⁴ and iPLA₂ inhibitor (IC₅₀=3.8 µM)⁸.
10 mg
50 mg

ST-350
12-epi-Scalaradial
98%, MW=428.6 [53527-28-9] Storage: -20°C
Scalaradial is a marine natural product isolated from Cacospongia sp. It is a potent inhibitor of bee venom PLA₂ (IC₅₀=0.07 µM)⁴⁵. The close analog, 12-epi-scalaradial has identical activity. It inhibits human recombinant sPLA₂ with 5-fold selectivity over cPLA₂ (IC₅₀=5.4 vs. 28 µM)²¹.
1 mg
5 x 1 mg

ST-325
Thioetheramide-PC
1-Palmitylthio-2-palmitoylamino-1,2-dideoxy-sn-glycero-3-phosphorylcholine
98%, MW=735.6, Storage: -20°C
A potent substrate analog inhibitor of snake venom PLA₂ (IC₅₀=2 µM)⁴⁶. It inhibits human recombinant sPLA₂ (IC₅₀=0.9 µM) selectively over cPLA₂²¹.
5 mg
25 mg

PLA₂ ASSAY SUBSTRATES

ST-500
1,2-bis(Heptanoylthio)glycerophosphocholine
98%, MW=513.7 [89019-63-6] Storage: -20°C
A novel PLA₁ and PLA₂ substrate for use in a thiol-based spectrophotometric assay^47,48.
5 mg
5 x 5 mg

ST-502
7-HC-arachidonate
7-Hydroxycoumarinyl-arachidonate
98%, MW=448.6, Storage: -20°C
PLA₂ fluorogenic substrate for use in assays with phospholipid and Ca²⁺. For use with purified enzyme, as this substrate is nonspecific⁴⁹.
10 mg
50 mg

ST-501
7-HC 6-heptenoate
7-Hydroxycoumarinyl 6-heptenoate
99%, MW=272.3, Storage: RT
PLA₂ fluorogenic substrate for use in assays without phospholipid and Ca²⁺. For use with purified, enzyme, as this substrate is nonspecific⁴⁹.
10 mg
50 mg

ST-503
7-HC-g-linolenate
7-Hydroxycoumarinyl-g-linolenate
98%, MW=422.6, Storage: -20°C
PLA₂ fluorogenic substrate for use in assays with phospholipid and Ca²⁺. For use with purified enzyme, as this substrate is nonspecific^49,50.
10 mg
50 mg

PHOSPHOLIPASE C INHIBITORS

ST-330
D609
Tricyclodecan-9-yl xanthogenate·K
98%, MW=266.5 [83373-60-8] Storage: -20°C
D609 is a selective inhibitor of phosphatidylcholine-specific PLC (PC-PLC)⁵¹ (IC₅₀~94 µM)⁵². It has been employed to establish the functional coupling of PC-PLC with sphingomyelinase⁵² and to establish the coupling of PC hydrolysis to the activation of Raf-1 protein kinase⁵³. A recent report showed that D609 indirectly inhibits phorbol ester-stimulated PLD activity⁵⁴. Possesses antitumor and antiviral activity⁵⁵.
5 mg
25 mg

EI-180
Neomycin sulfate
85% neomycin B, remainder neomycin C, MW=908.9 [1405-10-3] Storage: 0°C
An aminoglycoside antibiotic which inhibits PLC (IC₅₀=1-10 µM)^56,57,58 via binding to inositol phospholipids⁵⁹. It also inhibits phosphatidylcholine-PLD activity (IC₅₀=65 µM)⁶⁰ and induces Ca²⁺ mobilization and PLA₂ activation in human platelets⁶¹.
1 g
5 g

L-108
1-O-Octadecyl-2-O-methyl-sn-glycero-3-phosphorylcholine (ET-18-OCH₃)
99%, MW=523.7 [70641-51-9] Storage: -20°C
Inhibits phosphatidylinositol-specific PLC (IC₅₀=0.4-9.6 µM)⁶². Inhibits protein kinase C from various leukemic cells⁶³. Inhibits CoA-independent transacylase (IC₅₀=0.5 µM) an enzyme that remodels arachidonate between specific phospholipids⁶⁴. Induces apoptosis in HL-60 cells⁶⁵. Antineoplastic activity⁶⁶.
5 mg
25 mg

ST-300
RHC-80267 (U-57908)
1,6-bis-(cyclohexyloximinocarbonylamino)-hexane
98%, MW=394.6 [83654-05-1] Storage: RT
Diacylglycerol (DAG) is an important cellular source of arachidonate which may be released by the action of DAG lipase⁶⁷. RHC-80267 selectively inhibits DAG lipase activity in canine platelets (IC₅₀=4 µM)⁶⁸, bovine adrenal chromaffin cells⁶⁹, human adrenal glomerulosa cells⁷⁰, rat thyroid lobes⁷¹ and pancreatic minilobules⁷².
10 mg
50 mg

ST-391
U-73122
1-(6-((17b-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione
98%, MW=464.7 [112648-68-7] Storage: RT
Inhibits agonist induced phospholipase C (PLC) activation (IC₅₀=1.0-2.1 µM) in human platelets⁷³ and neutrophils⁷⁴. It also inhibits agonist induced down-regulation of muscarinic receptors in SK-N-SH neuroblastoma cells⁷⁵. It is a useful tool to investigate receptor-mediated PI turnover in signal transduction^76,77. It is a potent inhibitor of human neutrophil adhesion to biological surfaces as well as adhesion-dependent granule exocytosis and oxidative burst⁷⁸.
5 mg
25 mg

ST-392
U-73343
1-(6-((17b-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-2,5-pyrrolidine-dione
98%, MW=466.7 [142878-12-4] Storage: RT
Inactive analog of U-73122. May be used as a negative control^73,74.
5 mg
25 mg

PHOSPHOLIPASE D REAGENTS

ST-401
Phosphatidylbutanol
1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphobutanol
98%, MW=731.1, Storage: -20°C
Phosphatidylbutanol is a useful chromatographic standard for PLD assay⁷⁹.
Inquire

ST-400
Phosphatidylethanol
1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanol
98%, MW=703.0, Storage: -20°C
In the presence of ethanol, phospholipase D converts phosphatidylcholine to phosphatidylethanol^80,81. This conversion is the basis of a sensitive and selective assay for PLD activity in intact cells^82,83. Phosphatidylethanol is a useful chromatographic standard for this assay. For reviews on PLD mediated signalling see references^84,85,86.
10 mg
50 mg

ST-405
Propranolol
(?1-(Isopropylamino)-3-(1-naphthyloxy)-2-propanol·HCl
98%, MW=295.8 [3506-09-0] Storage: 0°C
Propranolol blocks PLD derived DAG formation by inhibiting phosphatidate phosphohydrolase (IC₅₀=70 µM)^87,88. It is a useful tool to discriminate between PLC or PLD mediated DAG production⁸⁶. It is also a b-adrenergic receptor blocking agent⁸⁹.
1 g
5 g

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