Cloning and sequence analysis of 10-deacetylbaccatin III-10-O-acetyl transferase gene and WRKY1 transcription factor from taxol-producing endophytic fungus Lasiodiplodia theobromea.

Abstract

In this study, we have isolated an endophytic fungal strain Lasiodiplodia theobromae from non-Taxus host plant Piper nigrum. The strain L. theobromae identity was confirmed by morphological characteristics and internal transcribed spacer sequence analysis. Taxol produced by L. theobromae was observed to be identical to the authentic taxol as analyzed by chromatography and spectroscopy methods. The quantity of taxol produced by the fungus was estimated to be 247 μg L-1, and fungal taxol showed potent cytotoxic activity towards cancer cell line. Evidence to support the independent production of taxol by L. theobromea, the gene encoding 10-deacetylbacccation-III-O-acetyltransferase (DBAT), as well as, for the first time, open reading frame (ORF) of WRKY1 transcription factor (TF) were cloned and sequenced. The predicted amino sequence of L. theobromae dbat gene shared high homology with the taxol-producing plant and fungal dbat gene. Not only dbat gene, ORF of WRKY1 TF too shared high homology with Taxus chinensis WRKY1 TF ORF. To the best of our knowledge, this is the first report on cloning of dbat gene and its transcription factor from endophytes of non-Taxus host plant.