Xanthocillin is a unique natural product with an isonitrile group and shows remarkable antibacterial activity. In this study, the genome of an endophytic fungus Penicillium chrysogenum MT-40 isolated from Huperzia serrata was sequenced, and the gene clusters with the potential to synthesize xanthocillin analogues were mined by local BLAST and various bioinformatics analysis tools. As a result, a biosynthetic gene cluster (named for) responsible for the biosynthesis of xanthocillin analogues was identified by further heterologous expression of the key genes in Aspergillus oryzae NSAR1. Specifically, the ForB catalyzes the synthesis of 2-formamido-3-(4-hydroxyphenyl) acrylic acid, and the ForG catalyzes the dimerization of 2-formamido-3-(4-hydroxyphenyl) acrylic acid to produce the xanthocillin analogue N, N'-(1, 4-bis (4-hydroxyphenyl) buta-1, 3-diene-2, 3-diyl) diformamide. The results reported here provide a reference for further discovery of xanthocillin analogues from fungi.
Penicillium chrysogenum/genetics* ; Huperzia/microbiology* ; Acrylates ; Multigene Family

Glutathione transferases (GSTs) are a family of multifunctional proteins that mainly catalyze the conjugation of intracellular glutathione (GSH) to a wide variety of endogenous and exogenous electrophilic compounds. GSTs play important roles in stress tolerance and in the detoxification metabolism in organisms. A novel GST gene, Pc gstB, was cloned from penicillin producing fungus Penicillium chrysogenum using RT-PCR. The open reading frame (ORF) of Pc gstB was 651 bp and encoded a peptide of 216 residues. The deduced amino acids sequence had conserved GST domain and showed 65% identity to the characterized Aspergillus fumigutus gstB. The entire ORF of Pc gstB was inserted into vector pTrc99A and transformed into Escherichia coli DH5alpha. Recombinant PcGstB was overexpressed and its GST activity toward substrate 1-chloro-2,4-dinitrobenzene (CDNB) was validated.
Catalysis ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Fungal Proteins ; genetics ; metabolism ; Genes, Bacterial ; genetics ; Glutathione Transferase ; genetics ; metabolism ; Open Reading Frames ; Penicillium chrysogenum ; enzymology ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Sequence Analysis, Protein