Snake venom phospholipase

A. indica L. Indian Aristolochia, also known as Indian birthwort, ishvara (Sanskrit), or adagam (Tamil), is a bitter climber native to India. The medicinal material consists of the rhizome, which is to resolve inflammation (India), counteract insect poison, and as an antipyretic (Philippines and Vietnam). The rhizome contains aristolochic acid, which inhibits in vitro and dose-dependent phospholipid hydrolysis by the human synovial fluid phospholipase A2, snake venom phospholipase A2, porcine pancreatic phospholipase A2, and human platelet phospholipase A2 (2). 

Influence of Intermolecular Spacing on Enzymic Hydrolysis of Lecithin Monolayers. When snake venom phospholipase A is injected under a lecithin monolayer, it splits lecithin into lysolecithin and free fatty acid. The change in polar groups of the monolayer results in a change of surface potential. However, if prior to injection of enzyme into the subsolution, a lecithin monolayer is compressed to such a surface pressure that the active site of the enzyme is unable to penetrate the monolayer, hydrolysis does not proceed. For monolayers of dipalmitoyl, egg, soybean, and dioleoyl lecithins the threshold surface pressure values at which hydrolysis does not proceed are 20, 30, 37, and 45 dynes per cm., respectively (40). This is also the same order for area per molecule in their surface pressure-area curves, indicating that enzymic hydrolysis of lecithin monolayers is influenced by the unsaturation of the fatty acyl chains and hence the intermolecular spacing in monolayers (40). 

Kini RM (1997) Venom phospholipase a2 enzymes. John Wiley Sons, Chichester Kini RM, Evans HJ (1989) A model to explain the pharmacological effects of snake venom phospholipases a2. Toxicon 27 613-35... 

Teshima, K., Kitagawa, Y., Samejima, Y., Kawauchi, S., Fijii, S., Ikeda, K., Hayashi, K., and Omori-Satoh, T. (1989). Role of calcium in the substrate binding and catalytic functions of snake venom phospholipases A. J. Biochem. (Tokyo) 106, 518-527. 

Zieler, H., Keister, D. B., Dvorak, J. A., and Ribeiro, J. M. (2001). A snake venom phospholipase A(2) blocks malaria parasite development in the mosquito midgut by inhibiting ookinete association with the midgut surface. ]. Exp. Biol. 204, 4157-4167. 

CHEMICAL CONNECTIONS 19A Snake Venom Phospholipases 19B Nonsteroidal Estrogen Antagonists... 

Section 26.5 Chemical Connections Snake Venom Phospholipases... 

Villar JAFP, Lima FTD, C.L. Veber, A.R.M. Oliveira, A.K. Calgarotto, S. Marangoni, da Silva SL (2008) Synthesis and evaluation of nitrostyrene derivative eompounds, new snake venom phospholipase A2 inhibitors. Toxicon 51(8) 1467-1478. doi 10.1016/j.toxicon.2008.03.023... 

Marinetti, G. V., J. Erbland, and E. Stotz The hydrolysis of lecithins by snake venom phospholipase A. Biochim. biophys. Acta (Amst.) 33, 403 (1959). 

While difficult to prepare, choline dehydrogenase has been solubilized and isolated in recent years by a number of procedures. These include ultrasonic disintegration and n-butanol treatment (80), extraction with the nonionic detergent, isooctylphenoxyethoxyethanol (81), and by incubation with snake venom phospholipase A (8 ). Purified choline dehydrogenase appears to be a flavoprotein, the flavin coenzyme being very tightly bound (8S). 

Positional distribution of fatty acids was determined by GLC analysis, after position-specific hydrolysis with snake venom phospholipase Az (7). ... 

Choumet, V., Faure, G., Robbe-Vincent, A., Saliou, B., Mazie, J.C. and Bon, C. (1992) Immunochemical analysis of a snake venom phospholipase A2 neurotoxin, crotoxin, with monoclonal antibodies. Mol. Immunol.,29, 871-882. 

Choumet, V., Saliou, B., Fideler, L., Chen, Y.C., Gubensek, F., Bon, C., and Delot, E. (1993) Snake-venom phospholipase A2 neurotoxins potentiation of a single-chain neurotoxin by the chaperon subunit of a two-component neurotoxin. Eur. J. Biochem., 211, 57-62. 

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