We successfully separated similarly sized proteins using these particles.
Sorting by sequence coverage showed a steep drop from full-length (~185 residues) to half-size proteins after about 4600 hits.
Clade 2 includes "half-size" proteins.
The detailed analysis was performed separately for each subfamily and, in the case of ABC-B transporters, also for full-length and half-size proteins.
Afterwards, members of each subfamily and, in the case of ABC-B transporters, also full-length and half-size proteins were analyzed separately.
However, for the MDR- and PDR-types, half-sized proteins with only one copy of the domains are also known.
One gene encoding a half-size MDR protein exhibited significantly reduced transcript levels.
The number of members of the 'small' subfamilies (ABC-A, -D, -E, -F, half-size ABC-B proteins, and unclassified ABC proteins) remained low and quite constant in the analyzed species, with only few exceptions, like an amplification of the ABC-F subfamily in R. oryzae.
Both full and half-size ABC-D proteins were identified in plant genomes.
Thus, our observations indicate that both full-length and half-size ABC-A proteins must have been present in the genome of the common ancestor of modern fungi.
Half-size ABC-A proteins (Group II) were exclusively limited to the two species of chytrid fungi included in our analysis, S. punctatus and B. dendrobatidis, where they occur together with full-size transporters.
