To discover novel antimalarial and anticancer compounds, we carried out a genome analysis, bioassay, metabolite profiling, and molecular docking of marine sediment actinobacteria strain GMY01. The whole-genome sequence analysis revealed that Streptomyces sp. GMY01 (7.9 Mbp) is most similar to Streptomyces sennicomposti strain RCPT1-4^T with an average nucleotide identity (ANI) and ANI based on BLAST+ (ANIb) values of 98.09 and 97.33% (>95%). An in vitro bioassay of the GMY01 bioactive on Plasmodium falciparum FCR3, cervical carcinoma of HeLa cell and lung carcinoma of HTB cells exhibited moderate activity (IC₅₀ value of 46.06; 27.31 and 33.75 µg/mL) with low toxicity on Vero cells as a normal cell (IC₅₀ value of 823.3 µg/mL). Metabolite profiling by LC-MS/MS analysis revealed that the active fraction of GMY01 contained carbohydrate-based compounds, C17H29NO14 (471.15880 Da) as a major compound (97.50%) and mannotriose (C18H32O16; 504.16903 Da, 1.96%) as a minor compound. Molecular docking analysis showed that mannotriose has a binding affinity on glutathione reductase (GR) and glutathione-S-transferase (GST) of P. falciparum and on autophagy proteins (mTORC1 and mTORC2) of cancer cells. Streptomyces sennicomposti GMY01 is a potential bacterium producing carbohydrate-based bioactive compounds with anti-plasmodial and anticancer activities and with low toxicity to normal cells.

Blister beetles are an important object of study in the field of agriculture and health. Despite being known to be important for the host animal, the gut bacteria of blister beetles have not been investigated deeply. This study aimed to provide the first initial description of the gut bacterial community of Mylabris pustulata as one species of blister beetles, based on a culture-independent technique. Adult blister beetles of the same colony were sampled and confirmed as Mylabris pustulata Thunberg. The gut content was used in high throughput sequencing, targeting the V3-V4 regions of 16S rRNA gene, and in the cultivation of resident bacteria. The results showed that higher bacterial richness was present in the gut communities when compared to the grown bacterial culture. Proteobacteria was confirmed as the most abundant phylum in the gut of M. pustulata, whereby most reads belonged to the class of Gammaproteobacteria. The dominant bacterial genera were determined as Enterobacter, Acinetobacter, Enterococcus, Klebsiella, and Pseudomonas. In addition, our cultivation attempts led to successful isolation of members of Klebsiella and Enterococcus. The subject of this study could be explored further to find the potential roles of these microbiota in the gut of the specific beetles and their bioprospects.