Phospholipases A(2) (PLA2s) are esterases that hydrolyze the sn-2 ester of glycerophospholipids and constitute one of the largest families of lipid hydrolyzing enzymes. The mammalian genome contains 10 enzymatically active secreted PLA2s (sPLA2s) and two sPLA2-related proteins devoid of lipolytic enzymatic activity. In addition to the well-established functions of one of these enzymes in digest...

Bothrops asper (Squamata: Viperidae) is the most important venomous snake in Central America, being responsible for the majority of snakebite accidents. Four basic PLA2s (pMTX-I to -IV) were purified from crude venom by a single-step chromatography using a CM-Sepharose ion-exchange column (1.5 × 15 cm). Analysis of the N-terminal sequence demonstrated that pMTX-I and III belong to the catalytic...

OBJECTIVE Group V secretory phospholipase A2 (GV sPLA2) has been detected in both human and mouse atherosclerotic lesions. This enzyme has potent hydrolytic activity towards phosphatidylcholine-containing substrates, including lipoprotein particles. Numerous studies in vitro indicate that hydrolysis of high density lipoproteins (HDL) and low density lipoproteins (LDL) by GV sPLA2 leads to the f...

This manuscript reviews and updates radiolabel-based enzyme assays designed to distinguish the activity of phospholipase A2 (PLA2) types in biological samples. This approach should be useful in lipidomics studies. The assays were originally designed to differentiate between Group IVA cytosolic PLA2 (GIVA cPLA2), Group VIA calcium-independent PLA2 (GVIA iPLA2), Group IIA secreted PLA2 (GIIA sPLA...

UNLABELLED BACKGROUND Cytosine methylation is an important chromatin modification that maintains genome integrity and regulates gene expression through transcriptional gene silencing. Major players in de novo methylation guided by siRNAs (known as RNA-directed DNA methylation, or RdDM), maintenance methylation, and active demethylation have been identified in Arabidopsis. However, active dem...

Mammalian cells contain many structurally and functionally diverse phospholipases A2 (PLA2) that catalyze the hydrolysis of sn-2 fatty acid from membrane phospholipid. Assays are described for measuring the activity of Group IVA cytosolic PLA2alpha(cPLAalpha) and for secreted PLA2s (sPLA2) that are suitable for purified enzymes and for measuring activity in crude cell lysates and culture medium...

Phospholipase A2 (PLA2) constitutes a diverse superfamily of enzymes which catalyze the deacylation of phospholipids. At least four types of PLA2 are potentially involved in arachidonic acid release in cells and tissues. Since all of them catalyze the same enzymatic reaction, it is difficult to distinguish between them in mixtures of enzymes normally present in biological samples. Utilizing spe...

Brain phospholipids are highly enriched in docosahexaenoic acid (DHA; 22:6n-3). Recent advances indicate that 22:6n-3 is released from brain phospholipids via the action of phospholipase A2 (PLA2) in response to several stimuli, including neurotransmission, where it then acts as a secondary messenger. Furthermore, it is now known that released 22:6n-3 is a substrate for several oxygenation enzy...

Ophidian envenomation is an important health problem in Brazil and other South American countries. In folk medicine, especially in developing countries, several vegetal species are employed for the treatment of snakebites in communities that lack prompt access to serum therapy. However, the identification and characterization of the effects of several new plants or their isolated compounds, whi...

Background The benefits from treatment with antivenom sera are indubitable. However, the mechanism for toxin neutralization has not been completely elucidated. A mixture of anti-bothropic and anti-crotalic horse antivenom has been reported to be more effective in neutralizing the effects of B. jararacussu snake venom than anti-bothropic antivenom alone. This study determined which regions in th...