Metal cofactors are necessary for the activity of alkylation by prenyl transfer in enzyme-catalyzed reactions. Rubber transferase (RuT, a cis-prenyl transferase) associated with purified rubber particles from Hevea brasiliensis, Parthenium argentatum and Ficus elastica can use magnesium and manganese interchangably to achieve maximum velocity. We define the concentration of activator required f...

In the rubber extraction process, guayule leaves represent an important biomass waste by-product, up to 32%, whose exploitation might contribute valorization of whole plant. The any its bioactive compounds or use as antioxidant seems be most feasible alternative. This study relates morphology individual content 35 (of 50 tentatively identified), determination overall phenolic and activity. morp...

Cut shoots of guayule (Parthenium argentatum Gray) were treated with four inhibitors of the glycolate pathway (alpha-hydroxypyridinemethanesulfonic acid; isonicotinic acid hydrazide, glycine hydroxamate, and amino-oxyacetate, AOA) in order to evaluate the role of photorespiratory intermediates in providing precursors for the biosynthesis of rubber. Photorespiratory CO(2) evolution in guayule le...

In screening a stem-bark cDNA library from guayule (Parthenium argentatum) for genes involved in isoprenoid biogenesis, we isolated a full-length gene for a P2 60s acidic ribosomal protein that shows sequence similarity to vertebrate (Rich and Steitz, 1987), invertebrate (Qian et al., 1987), and yeast (Beltrame and Bianchi, 1987, 1990; Remacha et al., 1988) 605 acidic ribosomal proteins (Table ...

INTRODUCTION Guayule (Parthenium argentatum Gray, Asteraceae) is a woody desert shrub (Whitworth and Whitehead 1991) which is under commercial development as a domestic source of hypoallergenic natural rubber (Siler and Cornish 1994; Carey et al. 1995; Cornish 1996, 1998; Cornish et al. 1996, 2001; Schloman et al. 1996; Siler et al. 1996; Cornish and Lytle 1999). To expedite commercialization, ...

Natural rubber biosynthesis in guayule (Parthenium argentatum Gray) is associated with moderately cold night temperatures. To begin to dissect the molecular events triggered by cold temperatures that govern rubber synthesis induction in guayule, the transcriptome of bark tissue, where rubber is produced, was investigated. A total of 11,748 quality expressed sequence tags (ESTs) were obtained. T...

Guayule (Parthenium argentatum A. Gray) is a desert-dwelling crop that can produce hard rubber for tires and has the potential to help meet water conservation needs of arid regions such as Southwest U.S. Previous work quantified cost environmental impact from guayule production. However, establishing economic viability domestic industry requires identifying value-added products residual non-rub...