Structural diversity in the 45-kilodalton merozoite surface antigen of Plasmodium falciparum

Jason A. Smythe, M. Gregory Peterson, Ross L. Coppel, Alan J. Saul, David J. Kemp, Robin F. Anders

Research output: Contribution to journalArticleResearchpeer-review

149 Citations (Scopus)


An integral membrane protein associated with the merozoite surface of Plasmodium falciparum termed merozoite surface antigen 2 (the 45-kDa merozoite surface antigen), occurs in antigenically diverse forms. Here we report the sequences of the MSA 2 gene from two other isolates of P. falciparum. The 43 N-terminal residues and the 74 C-terminal residues of all three MSA 2 sequences are highly conserved, but between these conserved regions there are dramatic differences among the alleles. Instead of the two copies of a 32-amino-acid repeat present in the MSA 2 of isolate FC27, MSA 2 from clone 3D7 and isolate Indochina 1 contain 5 and 12 copies respectively of the four amino acid sequence Gly Gly Ser Ala. The sequences flanking the repeats also differ among the three antigens. The repeats in MSA 2 appear to be immunodominant during natural infection, and antibodies to the repeat regions of different alleles react with a restricted number of parasite isolates.

Original languageEnglish
Pages (from-to)227-234
Number of pages8
JournalMolecular and Biochemical Parasitology
Issue number2
Publication statusPublished - 1 Jan 1990
Externally publishedYes


  • Allelic diversity
  • Antigenicity
  • Merozoite surface antigen
  • Plasmodium falciparum
  • Sequence analysis

Cite this