Molecular evidence for the contribution of methylobacteria to the pink-pigmentation process in pink-colored plants

Abstract The presence of Fe-efficient pink-pigmented methylobacterium (Fe-PPM) has been recently certified in the leaves of Celosia plant by priming of a specific Fe-siderophore receptor gene in our laboratory (GenBank accession number: FM955594). Considering Celosia as a pink-colored plant, a new proposal was made with regard to the possible contribution of Fe-PPM in the pigmentation process of this plant. To examine this, the quantitative expression level of methylobacterial-type Fe siderophore receptor gene was analyzed in differentially scored colored leaves of Celosia cristata. The normalized gene expression data analysis using 2−ΔΔCt method revealed that there is a positive correlation between the expression level of target gene and the intensity of the test leaf color as well as the total flavonoid content, total carotenoid content, and total antioxidative capacity as representatives of color intensity. The overall results lead to questioning'Do Fe-PPM reliably contributes the pigmentation process ...