Multi-integrated approach for unraveling small open reading frames potentially associated with secondary metabolism in Streptomyces.

IMPORTANCE: Due to their small size and special chemical features, small open reading frame (smORF)-encoding peptides (SEPs) are often neglected. However, they may play critical roles in regulating gene expression, enzyme activity, and metabolite production. Studies on bacterial microproteins have mainly focused on pathogenic bacteria, which are importance to systematically investigate SEPs in streptomycetes and are rich sources of bioactive secondary metabolites. Our study is the first to perform a global identification of smORFs in streptomycetes. We established a peptidogenomic workflow for non-model microbial strains and identified multiple novel smORFs that are potentially linked to secondary metabolism in streptomycetes. Our multi-integrated approach in this study is meaningful to improve the quality and quantity of the detected smORFs. Ultimately, the workflow we established could be extended to other organisms and would benefit the genome mining of microproteins with critical functions for regulation and engineering useful microorganisms.

[Diversity of Endogeny Eumycetes in Gynostemma pentaphyllum and Its Correlation with Gypenoside XLIX].

OBJECTIVE: To study the correlation between active components and endogeny eumycetes in Gynostemma pentaphyllum of different types from different habitats. METHODS: Endogeny eumycetes from different parts of Gynostemma pentaphyllum were isolated by general isolation methods. Insert method and point planting method were used for identification. The content of gypenoside XLIX were determined by HPLC. RESULTS: 125 endogeny eumycetes inhabiting in Gynostemma pentaphyllum were isolated from roots, rhizomes and leaves. By colony morphology and microscopic characteristics, 22 genera from 10 families, 7 orders, 2 classes were identified. Fusarium was the most abundant endogeny eumycetes in Gynostemma pentaphyllum with the account of 22. 4%. Penicillium and Leptosphaeria was 12. 8% and 9. 6% respectively. The correlation between Gypenoside XLIX and endogeny eumycetes in Gynostemma pentaphyllum was revealed. CONCLUSION: Endogeny eumycetes are diverse in species and quantity. The endogeny eumycetes species is related to the quality of Gynostemma pentaphyllum.