Application of MicroResp™ for quick and easy detection of plastic degradation by marine bacterial isolates.

Microplastic debris in the marine environment is a global problem. Biodegradable polymers are being developed as alternatives to petroleum-based plastics, and quick and easy methods for screening for bacterial strains that can degrade such polymers are needed. As a screening method, the clear zone method has been widely used but has technical difficulties such as plate preparation and interpretation of results.

sp. nov., isolated from Japanese faecal samples.

Two Gram-positive, anaerobic, non-spore-forming and coccoid or oval-shaped bacterial strains, namely, DN0138 and DN0266, were isolated from faecal samples of healthy Japanese people. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain DN0138 clustered with a species of the genus and was closely related to JCM 1471, JCM 1395, KB1 and '' Marseille-P2377, with sequence similarities of 98.6, 98.

Characterization and Demonstration of Mock Communities as Control Reagents for Accurate Human Microbiome Community Measurements.

Standardization and quality assurance of microbiome community analysis by high-throughput DNA sequencing require widely accessible and well-characterized reference materials. Here, we report on newly developed DNA and whole-cell mock communities to serve as control reagents for human gut microbiota measurements by shotgun metagenomics and 16S rRNA gene amplicon sequencing. The mock communities were formulated as near-even blends of up to 20 bacterial species prevalent in the human gut, span a wide range of genomic guanine-cytosine (GC) contents, and include multiple strains with Gram-positive type cell walls.

Validation and standardization of DNA extraction and library construction methods for metagenomics-based human fecal microbiome measurements.

Background: Validation and standardization of methodologies for microbial community measurements by high-throughput sequencing are needed to support human microbiome research and its industrialization. This study set out to establish standards-based solutions to improve the accuracy and reproducibility of metagenomics-based microbiome profiling of human fecal samples.

Results: In the first phase, we performed a head-to-head comparison of a wide range of protocols for DNA extraction and sequencing library construction using defined mock communities, to identify performant protocols and pinpoint sources of inaccuracy in quantification.