Jute (Corchorussp.) is one of the most important sources of natural fibre, covering ∼80% of global bast fibre production¹. OnlyCorchorus olitoriusandCorchorus capsularisare commercially cultivated, though there are more than 100Corchorusspecies²in the Malvaceae family. Here we describe high-quality draft genomes of these two species and their comparisons at the functional genomics level to support tailor-designed breeding. The assemblies cover 91.6% and 82.2% of the estimated genome sizes forC. olitoriusandC. capsularis, respectively. In total, 37,031C. olitoriusand 30,096C. capsularisgenes are identified, and most of the genes are validated by cDNA and RNA-seq data. Analyses of clustered gene families and gene collinearity show that jute underwent shared whole-genome duplication ∼18.66 million years (Myr) ago prior to speciation. RNA expression analysis from isolated fibre cells reveals the key regulatory and structural genes involved in fibre formation. This work expands our understanding of the molecular basis of fibre formation laying the foundation for the genetic improvement of jute.

The role of conserved nucleotides in nitrogen-fixation promoter function has been examined using both oligonucleotide and chemical mutagenesis to introduce base changes in the Klebsiella pneumoniae nifL and nifH promoters. Among ten mutations analysed, including six spontaneous mutations, base changes at -12, -13, -14, and -26, located in previously identified conserved sequences, perturbed the activity of the promoters, demonstrating that these sequences are required for transcription. Not all base changes produced similar strong promoter down phenotypes when the nifL and nifH promoters were compared: activation of the nifH promoter by the nifA gene product was less sensitive to base changes in conserved nucleotides than was activation of the equivalently altered nifL promoter by the nifA or ntrC products. We have found that the nifH promoter can be weakly activated by the ntrC product; this activation shows the same down response to base changes seen with ntrC activation of the nifL promoter. We present evidence that the efficient activation of the nifH promoter by nifA (but not ntrC) can be attributed to specific upstream sequences present in the nifH promoter.

Grammothele lineata, an endophyte isolated in our laboratory from jute (Corchorus olitorius acc. 2015) was found to be a substantial paclitaxel producer. Taxol and its related compounds, produced by this endophyte were extracted by growing the fungus in simple nutrient media (potato dextrose broth, PDB). Taxol was identified and characterized by different analytical techniques (TLC, HPLC, FTIR, LC-ESI-MS/MS) following its extraction by ethyl acetate. In PDB media, this fungus was found to produce 382.2 μgL^-1 of taxol which is about 7.6 x10³ fold higher than the first reported endophytic fungi, Taxomyces andreanae. The extracted taxol exhibited cytotoxic activity in an in vitro culture of HeLa cancer cell line. The fungal extract also exhibited antifungal and antibacterial activities against different pathogenic strains. This is the first report of a jute endophytic fungus harboring the capacity to produce taxol and also the first reported taxol producing species that belongs to the Basidiomycota phylum, so far unknown to be a taxol producer. These findings suggest that the fungal endophyte, Grammothele lineata can be an excellent source of taxol and can also serve as a potential species for chemical and genetic engineering to enhance further the production of taxol.