Cycad, Cycas

I. J. The lectin from leaves of Japanese cycad, Cycas revoluta Thunb. (gymnosperm) is a member of the jacalin-related family. Eur. J. Biochem. 2002, 269, 4335 1341... 

FIGURE 23.8 Real-time ESI-MS monitoring of (GlcNAc) hydrolysis catalyzed by class V chitinase from cycad Cycas revoluta). Enzymatic reaction was conducted in 20mM ammonium acetate buffer pH 5.0. Concentrations of the enzyme and the substrate were 0.1 and 25 i,M, respectively. Time-course data were corrected with ionization factors. 

The Values of Rate Constants and Binding Free Energy Changes for the Chitin Oligosaccharide Hydrolysis and Transglycosylation Catalyzed by Class V Chitinase from Cycad (Cycas revolta)... 

Some plants regularly eaten by humans contain neurotoxins that pose serious health problems. On Guam, for example, the seeds of Cycas circinalis used to be an important source of carbohydrates. Seeds of Cycas rumphii were ground into flour for tortillas. However, the seeds contain jS-N-methylamino-i-alanine, a suspected excitotoxin that overstimulates and destroys nerve cells. This compound causes a parkinsonism-like disease in macaques (Spencer et al, 1987). Other toxins have been proposed to be responsible for the disease, among them cycasin, another cycad toxin (Stone, 1993). 

Cycas circinalis, (Cycad, sago palm), C. spp. (Cycadaceae) [leaf, seed]... 

Viburnum prunifolium (Caprifoliaceae), Cycas revoluta (cycad) (Cycadaceae), Ginkgo biloba (Ginkgoaceae), Podocarpus montanus (Podocarpaceae), Rhus succedanea (Anacardiaceae)... 

Cycasin (= Cycas reooluta, C. spp. (cycad sago Yields genotoxic... 

N -Oxalyl-L-2,3-diaminopropionic acid (57) is derived from 2,3-diaminopropionic acid (69), which, in turn, is derived from asparagine (64) (Fig. 13.13), The oxalyl derivative (57) is a potent neurotoxin found in Lathyrus sativus and certain other legumes. The corresponding. /V -methyl derivative occurs in certain cycads such as Cycas drdnalis (Rosenthal, 1991). 

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