大戟乳胶：橡胶颗粒的微观形态和橡胶转移酶活性

Euphorbia characias latex: micromorphology of rubber particles and rubber transferase activity.

作者信息

Spanò Delia, Pintus Francesca, Esposito Francesca, Loche Danilo, Floris Giovanni, Medda Rosaria

机构信息

Department of Sciences of Life and Environment, University of Cagliari, Cittadella Universitaria, I-09042 Monserrato, CA, Italy.

Department of Chemical and Geological Sciences, University of Cagliari, Cittadella Universitaria, I-09042 Monserrato, CA, Italy.

出版信息

Plant Physiol Biochem. 2015 Feb;87:26-34. doi: 10.1016/j.plaphy.2014.12.008. Epub 2014 Dec 13.

DOI:10.1016/j.plaphy.2014.12.008

PMID:25532121

Abstract

We have recently characterized a natural rubber in the latex of Euphorbia characias. Following that study, we here investigated the rubber particles and rubber transferase in that Mediterranean shrub. Rubber particles, observed by scanning electron microscopy, are spherical in shape with diameter ranging from 0.02 to 1.2 μm. Washed rubber particles exhibit rubber transferase activity with a rate of radiolabeled [(14)C]IPP incorporation of 4.5 pmol min(-1)mg(-1). Denaturing electrophoresis profile of washed rubber particles reveals a single protein band of 37 kDa that is recognized in western blot analysis by antibodies raised against the synthetic peptide whose sequence, DVVIRTSGETRLSNF, is included in one of the five regions conserved among cis-prenyl chain elongation enzymes. The cDNA nucleotide sequence of E. characias rubber transferase (GenBank JX564541) and the deduced amino acid sequence appear to be highly homologous to the sequence of several plant cis-prenyltransferases.

摘要

我们最近对大戟乳胶中的天然橡胶进行了表征。在该研究之后，我们在此对该地中海灌木中的橡胶颗粒和橡胶转移酶进行了研究。通过扫描电子显微镜观察到的橡胶颗粒呈球形，直径范围为0.02至1.2μm。洗涤后的橡胶颗粒表现出橡胶转移酶活性，放射性标记的[(14)C]IPP掺入速率为4.5 pmol min(-1)mg(-1)。洗涤后橡胶颗粒的变性电泳图谱显示出一条37 kDa的单一蛋白带，在蛋白质印迹分析中，该蛋白带被针对合成肽产生的抗体识别，该合成肽的序列DVVIRTSGETRLSNF包含在顺式异戊二烯链延长酶中保守的五个区域之一。大戟橡胶转移酶的cDNA核苷酸序列（GenBank JX564541）和推导的氨基酸序列似乎与几种植物顺式异戊二烯转移酶的序列高度同源。