Titre du document / Document title

Identification of natural rubber and characterization of rubber biosynthetic activity in fig tree

Auteur(s) / Author(s)

HUNSEUNG KANG ⁽¹⁾ ; MIN YOUNG KANG ⁽¹⁾ ; HAN K.-H. ⁽¹⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Kumho Life and Environmental Science Laboratory, 1 Oryong-dong, Puk-gu, Kwangju, 500-712, COREE, REPUBLIQUE DE

Résumé / Abstract

Natural rubber was extracted from the fig tree (Ficus carica) cultivated in Korea as part of a survey of rubber producing plants. Fourier transform infrared and ¹³C nuclear magnetic resonance analysis of samples prepared by successive extraction with acetone and benzene confirmed that the benzene-soluble residues are natural rubber, cis-1,4-polyisoprene. The rubber content in the latex of fig tree was about 4%, whereas the rubber content in the bark, leaf, and fruit was 0.3%, 0.1%, and 0.1%, respectively. Gel-permeation chromatography revealed that the molecular size of the natural rubber from fig tree is about 190 kD. Similar to rubber tree (Hevea brasiliensis) and guayule (Parthenium argentatum Gray), rubber biosynthesis in fig tree is tightly associated with rubber particles. The rubber transferase in rubber particles exhibited a higher affinity for farnesyl pyrophosphate than for isopentenyl pyrophosphate, with apparent K_m values of 2.8 and 228 μM, respectively. Examination of latex serum from fig tree by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed major proteins of 25 and 48 kD in size, and several proteins with molecular mass below 20 and above 100 kD. Partial N-terminal amino acid sequencing and immunochemical analyses revealed that the 25- and 48-kD proteins were novel and not related to any other suggested rubber transferases. The effect of EDTA and Mg²⁺ ion on in vitro rubber biosynthesis in fig tree and rubber tree suggested that divalent metal ion present in the latex serum is an important factor in determining the different rubber biosynthetic activities in fig tree and rubber tree.

Revue / Journal Title

Plant physiology   ISSN 0032-0889   CODEN PPHYA5 

Source / Source

2000, vol. 123, n^o3, pp. 1133-1142 (1 p.1/4)

Langue / Language

Anglais

Editeur / Publisher

American Society of Plant Physiologists, Rockville, MD, ETATS-UNIS  (1926) (Revue)

Mots-clés anglais / English Keywords

Natural rubber ; Characterization ; Identification ; Biosynthesis ; Interspecific comparison ; Chemical composition ; Affinity ; Catalyst activity ; Transferases ; Ficus carica ; Hevea brasiliensis ; Parthenium argentatum ; Isoprene polymer ; Metal ion ; Divalent cation ; Enzyme ; Moraceae ; Dicotyledones ; Angiospermae ; Spermatophyta ; Euphorbiaceae ; Compositae ; Fruit tree ; Laticiferous plant ;

Mots-clés français / French Keywords

Caoutchouc naturel ; Caractérisation ; Identification ; Biosynthèse ; Comparaison interspécifique ; Composition chimique ; Affinité ; Activité catalytique ; Transferases ; Ficus carica ; Hevea brasiliensis ; Parthenium argentatum ; Isoprène polymère ; Ion métallique ; Cation divalent ; Enzyme ; Moraceae ; Dicotyledones ; Angiospermae ; Spermatophyta ; Euphorbiaceae ; Compositae ; Arbre fruitier ; Plante à latex ;

Mots-clés espagnols / Spanish Keywords

Caucho natural ; Caracterización ; Identificación ; Biosíntesis ; Comparación interespecífica ; Composición química ; Afinidad ; Actividad catalítica ; Transferases ; Ficus carica ; Hevea brasiliensis ; Parthenium argentatum ; Isopreno polímero ; Ión metálico ; Catión bivalente ; Enzima ; Moraceae ; Dicotyledones ; Angiospermae ; Spermatophyta ; Euphorbiaceae ; Compositae ; Arbol frutal ; Planta de latex ;

Localisation / Location

INIST-CNRS, Cote INIST : 3000, 35400009032906.0360