Is Ycf9 the Linchpin of Photosystem II?
Heterologous Expression for Structural and Functional Studies. HELEN CHUNG (Cornell University, Ithaca, NY 14853) GEOFFREY HIND (Brookhaven National Laboratory, Upton, NY 11973) . One group of ORF’s, ycfs (hypothetical chloroplast reading frames), have prove to be highly conserved between species of plants, and are thought to be genuine genes. ycf9 in particular has caught the attention of scientists. It encodes for a 62 amino acid protein that contains two alpha helices that are highly hydrophobic and is found in the PS II thylakoid membrane fractions. Gene knockout experiments have been done to determine the function and importance of this gene while fractionation experiments have been done to locate the whereabouts of its products. But no experiments have been done to isolate the protein in attempt to study its structure. In this experiment, I isolated ycf9 from the leaves of a spinach plant, expressed it in E. coli, and identified it through SDS PAGE. Circular dichroism spectroscop
