Phytochelatins synthesis

Scheller, H.V., Haung, B., Hatch, E. Goldsbrough, P.B. (1987). Phytochelatin synthesis and glutathione levels in response to heavy metals in tomato cells. Plant Physiology 85, 1031-5. 

Pawlik-Skowronska, B., di Toppi, L. S., Favali, M. A. et al. (2002). Lichens respond to heavy metals by phytochelatin synthesis. New Phytologist, 156, 95-102. 

De Vos ChHR, Vonk MJ, Vooijs R and Schat H (1992) Glutathione depletion due to copper-induced phytochelatin synthesis causes oxidative stress in Silene cucubalus. Plant Physiol 98 853-858. 

Clemens, S.K.M., E. J., Neumanna, D. and Schroede J.I. (1999). Tolerance to toxic metals by a gene family of phytochelatin synthesis from plants and yeast. EA1BO Journal 18 3325-3333. 

Stillman, M.J. Shaw, C.F. Jill and Suzuki, K.T (eds) (1992) MetaUothioneins Synthesis, Structure, and Properties of MetaUothioneins, Phytochelatins and Metal-... 

Robbins, A.H. and Stout, C.D. (1992) Metallothioneins Synthesis, Structure and Properhes of Metallothioneins, Phytochelatins, and Metal-Thiolate Complexes (eds M.l. ShDman, C.F. Shawlll and KT. Suzuki), VCH Publishers, Weinheim, pp. 31—54. 

In contrast to MT induction, the available evidence suggests that PC synthesis is not stimulated by direct transcriptional activation. PCs can be synthesised very rapidly (within 5 min) in response to metals entering the cells, even when protein synthesis is totally inhibited (Scheller et al., 1987 Robinson etal., 1988). Phytochelatin synthase thus appears to be a constitutive enzyme. Loeffler et al. (1989) have shown that, for the enzyme purified from Silene cucubalus, metal ion induction is a post-... 

Grill, E., Winnacker, E.-L. Zenk, M.H. (1986n). Synthesis of seven different homologous phytochelatins in metal-exposed Schizosac-charomyces pombe cells. FEBS Letters 197, 115-20. 

Stillman MJ, Shaw CF III, Suzuki KT (1992) Metallothioneins. Synthesis, structure, and properties of metallothioneins, phytochelatins and metal-thiolate complexes. VCH Publishers, New York Stratford IJ, Hoe S, Adams GE, Hardy C, Williamson C (1983) Abnormal radiosensitizing and cytotoxic properties of ortho-substituted nitroimidazoles. Int J Radiat Biol 43 31-43 Stubbe J, Kozarich JW (1987) Mechanisms of bleomycin-induced DNA degradation. Chem Rev 87 1107-1136... 

As an indirect effect of increased metal uptake, the physiological state of the cell can alter and defence mechanisms can be induced. Phytochelatin (metal binding proteins) synthesis and induction of free radical quenching enzymes and metabolites were frequently observed. Especially the latter can protect membranes against oxidative breakdown. 

M. J. Stillman, C. F. Shaw 111, and K. T. Suzuki, eds, Metallothioneins Synthesis, Structure and Properties of Metallothioneins, Phytochelatins and Metalthiolate Ccomplexes , Wiley, New York, 1992. 

Plants could maintain the necessary concentrations of essential metal ions in cells by homeostatic mechanisms. They are also involved in the reduction of damage induced by heavy metal toxicity. One of the major tolerance mechanisms is chelation of heavy metals by a family of peptide ligands, the phytochelatins (similar to other xenobiotics) [108], The molecular basis for the chelators and chaperone synthesis is well known and could be applied in the modification of tolerant plants. Tolerance to Cd and As is largely dependent on the phytochelatin pathway, but molecular biology of Cd hypertolerance in certain plant species, such as the... 

EXPERIMENT 7.2 SOLID-PHASE PEPTIDE SYNTHESIS AND HPLC PURIFICATION OF THE PHYTOCHELATIN, PENTAPEPTIDE, (y-Glu-Cys)2-Gly (PC2)... 

Phytochelatins [ y-Glu-Cys) -Gly], PC , may be induced by a variety of heavy metals in vivo and in vitro. The response is complex and varies with each system of study. It is certain, however, that Cd2+ is by far the strongest inducer of PC synthesis and is the... 

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