Solution NMR structures of Pyrenophora tritici-repentis ToxB and its inactive homolog reveal potential determinants of toxin activity.

ABSTRACT: Pyrenophora tritici-repentis Ptr ToxB (ToxB) is a proteinaceous host-selective toxin produced by Pyrenophora tritici-repentis (P. tritici-repentis), a plant pathogenic fungus that causes the disease tan spot of wheat. One feature that distinguishes ToxB from other host-selective toxins is that it has naturally occurring homologs in non-pathogenic P. tritici-repentis isolates that lack toxic activity. There are no high-resolution structures for any of the ToxB homologs, or for any protein with >30% sequence identity, and therefore what underlies activity remains an open question. Here, we present the NMR structures of ToxB and its inactive homolog Ptr toxb. Both proteins adopt a β-sandwich fold comprising three strands in each half that are bridged together by two disulfide bonds. The inact

SUBMITTER: Nyarko A 

PROVIDER: S-EPMC4162193 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature