3 research outputs found
Data_Sheet_1_Lobophorin Producing Endophytic Streptomyces olivaceus JB1 Associated With Maesa japonica (Thunb.) Moritzi & Zoll..PDF
In this study, we focused on endophytes of Maesa japonica (Thunb.) Moritzi & Zoll. and the plant-microbe interaction at metabolite levels. We isolated seven endophytes associated with M. japonica (JB1−7), and focused on Streptomyces olivaceus JB1 because of antibacterial activities of its secondary metabolites. We confirmed lobophorin analogs production from the bacterial strain JB1 by using spectroscopic techniques such as NMR, UV, and LC/Q-TOF-MS. In the LC/MS system, thirteen reported lobophorin analogs and twelve unreported analogs were detected. Among metabolites, lobophorin A was clearly detected in the dried foliar residues of M. japonica which implies that JB1 resides in the host and accumulates its secondary metabolites likely interacting with the plant. Antimicrobial activity tests of the secondary metabolites against undesirable contaminants isolated from the external surface of M. japonica supported the host and microbe mutualistic relationship. In the meantime, lobophorin producing Streptomyces spp. were isolated from marine environments such as marine sediments, algae, corals, and sponges. As lobophorin producing Streptomyces is isolated commonly from marine environments, we conducted a saline water stress tolerance test with JB1 showing saline medium does not accelerate the growth of the bacterium.</p
DataSheet_1_Pentacyclic triterpenoids saponins pannosides A-E from Tripolium pannonicum.pdf
Five previously undescribed pentacyclic triterpenoid saponins, pannoside A–E (1–5), were discovered from the whole plant of seashore aster, Tripolium pannonicum, collected from the Songdo tidal flat, Incheon, Korea. The planar structures of pannosides were elucidated as pentacyclic triterpenoids bearing sugar moieties and 3-hydroxybutyrate (3-HB) based on the interpretation of the NMR, IR spectroscopic and MS data. The relative configurations of the aglycone and sugar moieties of 1–5 were determined based on careful analysis of ROESY correlations. To determine the absolute configuration of 3-hydroxybutyrate, we utilized the phenylglycine methyl ester (PGME) derivatization with LC-MS chromatographic analysis. Pannoside E (5) exhibited inhibitory activities against diverse cancer cell lines including prostate carcinoma and non-small cell lung carcinoma, with IC50 values of 0.34 and 0.89 μM, respectively. Pannosides are the first triterpenoid saponin isolated from T. pannonicum, implying that undiscovered secondary metabolites from a halophyte could be a good source of bioactive compounds.</p
Genomic and Metabolomic Analyses of <i>Nocardiopsis maritima</i> YSL2 as the Mycorrhizosphere Bacterium of <i>Suaeda maritima</i> (L.) Dumort
Nine
bacteria were isolated from the episphere of Suaeda
maritima (L.) Dumort. Among them, the bacterial strain YSL2
displayed the highest antimicrobial activity on agar plates and exhibited
significant novelty compared with other bacteria based on 16S rRNA
analysis. Consequently, Nocardiopsis maritima YSL2T was subjected to phenotypic characterization and whole-genome
sequencing. Phylogenetic analysis revealed its close association with Nocardiopsis aegyptia SNG49T. Furthermore, genomic
analysis of strain YSL2T revealed the presence of various
gene clusters, indicating its potential for producing antimicrobial
secondary metabolites. Upon cultivation on a large scale, maritiamides
A and B (1 and 2) were isolated and characterized
as cyclic hexapeptides based on nuclear magnetic resonance, ultraviolet,
infrared, and mass spectrometric data. The absolute configurations
of the amino acid residues in the maritiamides were determined through
chiral derivatization, utilizing FDAA and GITC. Maritiamides 1 and 2 exhibited promising antibacterial activities
against Staphylococcus epidermidis and weakly inhibited
the growth of Escherichia coli and Pseudomonas
fluorescens
