Poster: Heavy metals & phytoremediation

Abs # 53: Arsenate reduction in arsenic-hyperaccumulating fern Pteris vittata and a proteobacterium isolated from its phyllosphere

Presenter:	Kertulis, Gina , kertulis@ufl.edu
Authors	Rathinasabapathi, Bala  (A)   Raman, Suresh Babu  (A)   Kertulis, Gina  (B)   Ma, Lena  (B)
Affiliations:	(A): University of Florida, Horticultural Sciences (B): University of Florida, Soil and Water Science

Chinese brake fern Pteris vittata is a hyperaccumulator of arsenic. An arsenic- resistant bacterium (ASRB) was isolated from the phyllosphere of P. vittata , growing in an arsenic-contaminated soil. Based on microbiological tests and phylogenetic analyses of the 16SrDNA sequence, the ASRB was identified to be a β subclass proteobacterium. The objective of this study was to characterize arsenate reduction by P. vittata fronds and by the ASRB. Sodium arsenate was supplied to leaf disks of P. vittata via vaccuum infiltration and to cells of ASRB via the culture medium. The tissue and cells were extracted and analyzed for total arsenate and proportions of As III. About 90% and 95% arsenic in P.vittata fronds and ASRB cells respectively were in the form of As(III)following an incubation for 6h or 24h. Arsenate reduction was promoted by light in P. vittata.