Structural fingerprinting: Subgrouping of comoviruses by structural studies of red clover mottle virus to 2.4-angstrom resolution and comparisons with other comoviruses

Red clover mottle virus (RCMV) is a member of the comoviruses, a group of p icornavirus-like plant viruses. The X-ray structure of RCMV strain S has be en determined and refined to 2.4 Angstrom. The overall structure of RCMV is similar to that of two other comoviruses, Cowpea mosaic vines (CPMV) and B ean pod mottle virus (BPMV). The sequence of the coat proteins of RCMV stra in O were modeled into the capsid structure of strain S without causing any distortion, confirming the close resemblance between the two strains. By c omparing the RCMV structure with that of other comoviruses, a structural fi ngerprint at the N terminus of the small subunit was identified which allow ed subgrouping of comoviruses into CPMV-like and BPMV-like viruses.