Comparative sequence and structure of different isolates of citrus exocortis viroid

Abstract

The nucleotide sequences of two new Australian isolates of citrus exocortis viroid (CEV), CEV-DE25 and CEV-DE26, have been determined and compared with the previously sequenced Australian isolate, CEV-A (J. E. Visvader, A. R. Gould, G. E. Breuning, and R. H. Symons. FEBS Lett.137, 288-292 (1982).) and a Californian isolate, CEV-C (H. J. Gross, G. Krupp, H. Domdey, M. Raba, P. Jank, C. Lossow, H. Alberty, K. Ramm, and H. L. Sanger. Eur. J. Biochem.121, 249-257 (1982).). Sequencing of recombinant DNA clones prepared from purified CEV-A showed sequence heterogeneity at four nucleotide residues which was not observed by direct RNA sequencing. The data indicated that purified CEV-A contained mino..