Exploring the potential of marine microbes in clinical management of Alzheimer's disease: A road map for bioprospecting and identifying promising isolates

Marine Organisms as Alkaloid Biosynthesizers of Potential Anti-Alzheimer Agents

The incidence of neurodegenerative diseases, such as Alzheimer's disease (AD), increases continuously demanding the urgent development of anti-Alzheimer's agents. Marine organisms (MO) have to create their own defenses due to the adverse environment where they live and so synthesize several classes of compounds, such as akaloids, to defend themselves. Therefore, the identification of marine natural products with neuroprotective effects is a necessity. Being that AD is not only a genetic but also an environmental complex disease, a treatment for AD remains to discover. As the major clinical indications (CI) of AD are extracellular plaques formed by β-amyloid (Aβ) protein, intracellular neurofibrillary tangles (NFTs) formed by hyper phosphorylated τ-protein, uncommon inflammatory response and neuron apoptosis and death caused by oxidative stress, alkaloids that may decrease CI, might be used against AD. Most of the alkalolids with those properties are derivatives of the amino acid tryptophan mainly with a planar indole scaffold. Certainly, alkaloids targeting more than one CI, multitarget-directed ligands (MTDL), have the potential to become a lead in AD treatment. Alkaloids to have a maximum of activity against CI, should be planar and contain halogens and amine quaternization.

Draft Genome Sequence of Mycolicibacterium sp. Strain 018/SC-01/001, Isolated from the Marine Sponge Iotrochota sp

Here, we report the draft genome sequence of a marine bacterium, Mycolicibacterium sp. strain 018/SC-01/001, isolated from the marine sponge Iotrochota sp. collected from the Singapore Strait. The analysis of the bacterial genome using the bioinformatics tool antiSMASH 4.0.2 revealed the presence of a number of unique natural product biosynthetic pathways.

Here, we report the draft genome sequence of a marine bacterium, Mycolicibacterium sp. strain 018/SC-01/001, isolated from the marine sponge Iotrochota sp. collected from the Singapore Strait. The analysis of the bacterial genome using the bioinformatics tool antiSMASH 4.0.2 revealed the presence of a number of unique natural product biosynthetic pathways.

Draft Genome Sequence of Bacillus sp. Strain 007/AIA-02/001, Isolated from the Marine Sponge Coelocarteria singaporensis

We report the draft genome sequence of a marine bacterium, Bacillus sp. strain 007/AIA-02/001, isolated from the marine sponge Coelocarteria singaporensis, obtained from water off the coast of Singapore. The analysis of the bacterial genome using the bioinformatics tool antiSMASH 4.0.2 showed the presence of a number of unique natural product biosynthetic pathways.

We report the draft genome sequence of a marine bacterium, Bacillus sp. strain 007/AIA-02/001, isolated from the marine sponge Coelocarteria singaporensis, obtained from water off the coast of Singapore. The analysis of the bacterial genome using the bioinformatics tool antiSMASH 4.0.2 showed the presence of a number of unique natural product biosynthetic pathways.

Integrated Genomic and Metabolomic Approach to the Discovery of Potential Anti-Quorum Sensing Natural Products from Microbes Associated with Marine Samples from Singapore

With 70% of the Earth's surface covered in water, the marine ecosystem offers immense opportunities for drug discovery and development. Due to the decreasing rate of novel natural product discovery from terrestrial sources in recent years, many researchers are beginning to look seaward for breakthroughs in new therapeutic agents. As part of an ongoing marine drug discovery programme in Singapore, an integrated approach of combining metabolomic and genomic techniques were initiated for uncovering novel anti-quorum sensing molecules from bacteria associated with subtidal samples collected in the Singapore Strait. Based on the culture-dependent method, a total of 102 marine bacteria strains were isolated and the identities of selected strains were established based on their 16S rRNA gene sequences. About 5% of the marine bacterial organic extracts showed quorum sensing inhibitory (QSI) activity in a dose-dependent manner based on the Pseudomonas aeruginosa QS reporter system. In addition, the extracts were subjected to mass spectrometry-based molecular networking and the genome of selected strains were analysed for known as well as new biosynthetic gene clusters. This study revealed that using integrated techniques, coupled with biological assays, can provide an effective and rapid prioritization of marine bacterial strains for downstream large-scale culturing for the purpose of isolation and structural elucidation of novel bioactive compounds.