Reference "Root tip-dependent, active riboflavin secretion by Hyoscyamus albus hairy roots under iron deficiency"

Reference ID

54975

Title

Root tip-dependent, active riboflavin secretion by Hyoscyamus albus hairy roots under iron deficiency

Source

Plant Physiol Biochem, 2008, vol. 46, pp. 452-460

Authors (4)

Higa-A	Miyamoto-E
ur-Rahman-L	Kitamura-Y

Abstract

Hyoscyamus albus hairy roots with/without an exogenous gene (11 clones) were
established by inoculation of Agrobacterium rhizogenes. All clones cultured
under iron-deficient condition secreted riboflavin from the root tips into the
culture medium and the productivity depended on the number and size of root tips
among the clones. A decline of pH was observed before riboflavin production and
root development. By studying effects of proton-pump inhibitors, medium
acidification with external organic acid, and riboflavin addition upon pH change
and riboflavin productivity, we indicate that riboflavin efflux is not directly
connected to active pH reduction, and more significantly active riboflavin
secretion occurs as a response to an internal requirement in H. albus hairy
roots under iron deficiency.