anti-TRAP (AT) protein specific to BacilliIn Bacillus subtilis and related bacteria, AT binds to the TRAP protein, (tryptophan-activated trp RNA-binding attenuation protein), effectively disrupting interaction of TRAP with mRNAs. Upon binding of tryptophan, TRAP (which forms a complex of 11 identical subunits) interacts with a specific location in the leader RNA and blocks translation of the tryptophan biosynthetic operon. AT, in turn, recognizes the tryptophan-activated TRAP complex and prevents RNA binding. AT is expressed in response to high levels of uncharged tryptophan tRNA. AT contains a zinc-binding motif that closely resembles the zinc-binding motifs in the zinc-finger region of DnaJ/Hsp40. AT has been shown to form homo-dodecameric assemblies, and can actually do that in two different relative orientations, resulting in two different dodecamers. Recent data suggest that the trimeric form of AT may be the biologically relevant active complex.