Genome sequence of bioactive streptomycete isolated from mangrove forest in East Malaysia, Streptomyces monashensis MUSC 1JT

Members of Streptomyces are known to be prolific producers of bioactive compounds, including antibacterials, antioxidants, neuroprotective agents as well as immunomodulatory compounds. Isolated from East Malaysia, Streptomyces monashensis MUSC 1JT (=DSM 103626T =MCCC 1K03221T) was initially described as a novel streptomycete using a polyphasic approach. Based on phylogenetic analyses, the closely strains related to MUSC 1JT were identified as Streptomyces corchorusii DSM 40340T (98.7 %), Streptomyces olivaceoviridis NBRC 3066T (98.7 %), Streptomyces canarius NBRC 13431T (98.6 %), and Streptomyces coacervatus AS-0823T (98.4 %). Seven day fermentative extracts of MUSC 1JT exhibited potent antioxidant activity and significant cytotoxic activity against colon cancer cell lines, thus the strain was selected for whole genome sequencing. The genome size of MUSC 1JT is described to be 10.3 Mbps with G + C content of 71.50%. Based on antiSMASH analysis, the strain possessess great genomic potential, having fifty nine biosynthetic gene clusters related to production of secondary metabolites and antibiotics. Therefore, these results serve a foundation for further in-depth investigation to harness its bioactive potential for the development of highly valuable pharmaceutical products.

Potensi Bacillus licheniformis dan Streptomyces olivaceoviridis sebagai Penghambat Pertumbuhan Jamur Saprolegnia sp. Penyebab Saprolegniasis pada Ikan secara In Vitro [Potential of Bacillus licheniformis and Streptomyces olivaceoviridis as Inhibiting The Growth of Fungus Saprolegnia sp, Cause Saprolegniasis on Fish by Using In Vitro]

Saprolegniasis is a fungal disease on fish caused by Saprolegnia sp, which is saprophyte, damaging healthy tissue and makes the immune system in fish deacreased. The uniquennes of Saprolegnia sp has the main components of the cell wall in the form of chitin that was instrumental in shaping the structure of the tip growth of fungal hyphae. Control of fungal pathogenic Saprolegnia sp can use chitinolytic microorganisms based on ability to produce chitinase for example using bacteria. This study aims to potential of Bacillus licheniformis and Streptomyces olivaceoviridis as inhibiting the growth of fungus Saprolegnia sp, cause saprolegniasis on fish by using in vitro. The research method is experimental with completely randomized design (CRD), which consists of four treatments with five replications. The experimental used is A (Saprolegnia sp and Bacillus licheniformis), B (Saprolegnia sp and Streptomyces olivaceoviridis), C negative control (Saprolegnia sp) and D positive control (Saprolegnia sp and Ketokonazol 2 %). The main parameters measured were observed inhibition zone on each treatment. Supporting parameters were observed is an observation of abnormal hpyphae structure after being induced by bacteria Bacillus licheniformis dan Streptomyces olivaceoviridis. Data were analyzed using analysis of variants (ANOVA) and to know the difference between treatments were determined by Tukey honestly significant difference (Tukey HSD) Test. The results showed that the potential of chitinolytic Bacillus licheniformis can provide a good barrier of 4,62 cm by 5,48 cm compared Streptomyces olivaceoviridis in inhibiting the growth Saprolegnia sp. Suggestions in this research is the need to further research on the value of chitinase Bacillus licheniformis and Streptomyces olivaceoviridis. Further research by using in vivo.