MIBiG 4.0: advancing biosynthetic gene cluster curation through global collaboration.

Specialized or secondary metabolites are small molecules of biological origin, often showing potent biological activities with applications in agriculture, engineering and medicine. Usually, the biosynthesis of these natural products is governed by sets of co-regulated and physically clustered genes known as biosynthetic gene clusters (BGCs). To share information about BGCs in a standardized and machine-readable way, the Minimum Information about a Biosynthetic Gene cluster (MIBiG) data standard and repository was initiated in 2015.

A high-quality genome of the early diverging tychoplanktonic diatom Paralia guyana.

The diatom Paralia guyana is a tychoplanktonic microalgal species that represents one of the early diverging diatoms. P. guyana can thrive in both planktonic and benthic habitats, making a significant contribution to the occurrence of red tide events.

Progress and future directions for seaweed holobiont research.

In the marine environment, seaweeds (i.e. marine macroalgae) provide a wide range of ecological services and economic benefits.

Impact of host species on assembly, composition, and functional profiles of phycosphere microbiomes.

Unlabelled: Microalgal microbiomes play vital roles in the growth and health of their host, however, their composition and functions remain only partially characterized, especially across microalgal phyla. In this study, a natural seawater microbiome was introduced to three distinct, axenic species of microalgae, the haptophyte the chlorophyte and the diatom (previously ), and its divergence and assembly under constant illumination was monitored over 49 days using 16S rRNA amplicon and metagenomic analyses. The microbiomes had a high degree of host specificity in terms of taxonomic composition and potential functions, including CAZymes profiles.

Two high-quality genomes provide new insights into their evolution as obligate algal heterotrophs and their pathogenicity.

Unlabelled: The majority of the nearly 10,000 described species of green algae are photoautotrophs; however, some species have lost their ability to photosynthesize and become obligate heterotrophs that rely on parasitism for survival. Two high-quality genomes of the heterotrophic algae Pz20 and Pz23 were obtained using short- and long-read genomic as well as transcriptomic data. The genome sizes were 31.

Chromosome-level reference genome and resequencing of 322 accessions reveal evolution, genomic imprint and key agronomic traits in adzuki bean.

Adzuki bean (Vigna angularis) is an important legume crop cultivated in over 30 countries worldwide. We developed a high-quality chromosome-level reference genome of adzuki bean cultivar Jingnong6 by combining PacBio Sequel long-read sequencing with short-read and Hi-C technologies. The assembled genome covers 97.

Antagonistic activity of against the emerging fish pathogen in aquaculture feed algae.

Aquaculture provides a rich resource of high-quality protein; however, the production is challenged by emerging pathogens such as . While probiotic bacteria have been proposed as a sustainable solution to reduce pathogen load in aquaculture, their application requires a comprehensive assessment across the aquaculture food chain. The purpose of this study was to determine the antagonistic effect of the potential probiotic bacterium against the emerging fish pathogen in aquaculture feed algae that can be an entry point for pathogens in fish and shellfish aquaculture.

The ability of Phaeobacter inhibens to produce tropodithietic acid influences the community dynamics of a microalgal microbiome.

Microbial secondary metabolites facilitate microbial interactions and are crucial for understanding the complexity of microbial community dynamics. The purpose of the present study was to determine how a secondary metabolite producing marine bacteria or its metabolite deficient mutant affected the microbiome of the marine microalgae Tetraselmis suecica during a 70 day long co-evolution experiment. Using 16S rRNA gene amplicon sequencing, we found that neither the tropodithietic acid (TDA)-producing Phaeobacter inhibens wildtype nor the TDA-deficient mutant had major impacts on the community composition.

Long-read genome sequencing provides novel insights into the harmful algal bloom species Prymnesium parvum.

Prymnesium parvum is a toxin-producing haptophyte that causes harmful algal blooms worldwide, which are often associated with massive fish-kills and subsequent economic losses. In here, we present nuclear and plastid genome assemblies using PacBio HiFi long reads and DNBseq short reads for the two P. parvum strains UTEX 2797 and CCMP 3037, representing producers of type A prymnesins.

Sequence-Based Characterization of Microalgal Microbiomes: Impact of DNA Extraction Protocol on Yield and Community Composition.

The bacterial communities associated with microalgae are vital for the growth and health of the host, and engineering algal microbiomes can enhance the fitness of the algae. Characterization of these microbiomes mostly relies on sequencing of DNA, which can be extracted with an array of protocols that potentially impact DNA quantity and quality and thus potentially affect subsequent analyses of microbiome composition. Here, we extracted DNA from Isochrysis galbana, Tetraselmis suecica, and Conticribra weissflogii microbiomes using four different protocols.

Chemotaxis increases metabolic exchanges between marine picophytoplankton and heterotrophic bacteria.

Behaviours such as chemotaxis can facilitate metabolic exchanges between phytoplankton and heterotrophic bacteria, which ultimately regulate oceanic productivity and biogeochemistry. However, numerically dominant picophytoplankton have been considered too small to be detected by chemotactic bacteria, implying that cell-cell interactions might not be possible between some of the most abundant organisms in the ocean. Here we examined how bacterial behaviour influences metabolic exchanges at the single-cell level between the ubiquitous picophytoplankton Synechococcus and the heterotrophic bacterium Marinobacter adhaerens, using bacterial mutants deficient in motility and chemotaxis.

Tropodithietic Acid, a Multifunctional Antimicrobial, Facilitates Adaption and Colonization of the Producer, Phaeobacter piscinae.

In the marine environment, surface-associated bacteria often produce an array of antimicrobial secondary metabolites, which have predominantly been perceived as competition molecules. However, they may also affect other hallmarks of surface-associated living, such as motility and biofilm formation. Here, we investigate the ecological significance of an antibiotic secondary metabolite, tropodithietic acid (TDA), in the producing bacterium, Phaeobacter piscinae S26.

The Cycas genome and the early evolution of seed plants.

Cycads represent one of the most ancient lineages of living seed plants. Identifying genomic features uniquely shared by cycads and other extant seed plants, but not non-seed-producing plants, may shed light on the origin of key innovations, as well as the early diversification of seed plants. Here, we report the 10.

Genome Sequences of Two Strains of Provide Insight Into the Protothecosis Evolution.

The alga is the only chlorophyte known to be involved in a series of clinically relevant opportunistic infections in humans and animals, namely, protothecosis. Most pathogenic cases in humans are caused by . In order to investigate the evolution of and the genetic basis for its pathogenicity, the genomes of two strains S1 and S931 were sequenced using Nanopore long-read and Illumina short-read technologies.

Role is in the eye of the beholder-the multiple functions of the antibacterial compound tropodithietic acid produced by marine Rhodobacteraceae.

Many microbial secondary metabolites have been studied for decades primarily because of their antimicrobial properties. However, several of these metabolites also possess nonantimicrobial functions, both influencing the physiology of the producer and their ecological neighbors. An example of a versatile bacterial secondary metabolite with multiple functions is the tropone derivative tropodithietic acid (TDA).

The Draft Genome of the Centric Diatom Conticribra weissflogii (Coscinodiscophyceae, Ochrophyta).

Here, we present a 231 Mb draft genome of the centric diatom Conticribra weissflogii CCMP1336. Comparative genomics of C. weissflogii and other Ochrophyta support the existence of unique carbon-concentrating mechanisms and chitin metabolic processes in diatoms.

Draft Genome Sequences of Nine Environmental Bacterial Isolates Colonizing Plastic.

Here, we report the draft genome sequences of nine bacterial isolates obtained after laboratory incubation of seawater, soil, and wastewater samples with polylactic acid, polyethylene, or polyethylene terephthalate film for 2 weeks. Assuming colonization as a prerequisite of degradation, these strains could contribute to a solution to the global plastic waste problem.

Effect of polymer type on the colonization of plastic pellets by marine bacteria.

Plastic is omnipresent in the oceans and serves as a surface for biofilm-forming microorganisms. Plastic debris comprises different polymers, which may influence microbial colonization; here, we evaluated whether polymer type affects bacterial biofilm formation. Quantifying the biofilm on polyethylene (PE), polypropylene (PP) or polystyrene (PS) pellets by six marine bacterial strains (Vibrio,Pseudoalteromonas,Phaeobacter) demonstrated that each strain had a unique colonization behavior with either a preference for PS or PP over the other polymer types or no preference for a specific plastic type.

The -Group Bacterium as a Safe Probiotic Solution for Aquaculture.

Phaeobacter inhibens has been assessed as a probiotic bacterium for application in aquaculture. Studies addressing the efficacy and safety indicate that maintains its antagonistic activity against pathogenic vibrios in aquaculture live cultures (live feed and fish egg/larvae) while having no or a positive effect on the host organisms and a minor impact on the host microbiomes. While produces antibacterial and algicidal compounds, no study has so far found a virulent phenotype of cells against higher organisms.

Production of the antimicrobial compound tetrabromopyrrole and the Pseudomonas quinolone system precursor, 2-heptyl-4-quinolone, by a novel marine species Pseudoalteromonas galatheae sp. nov.

Novel antimicrobials are urgently needed due to the rapid spread of antibiotic resistant bacteria. In a genome-wide analysis of Pseudoalteromonas strains, one strain (S4498) was noticed due to its potent antibiotic activity. It did not produce the yellow antimicrobial pigment bromoalterochromide, which was produced by several related type strains with which it shared less than 95% average nucleotide identity.

Changes in the Microbiome of Mariculture Feed Organisms after Treatment with a Potentially Probiotic Strain of Phaeobacter inhibens.

The genus has been explored as probiotics in mariculture as a sustainable strategy for the prevention of bacterial infections. Its antagonistic effect against common fish pathogens is predominantly due to the production of the antibacterial compound tropodithietic acid (TDA), and TDA-producing strains have repeatedly been isolated from mariculture environments. Despite many trials targeting pathogens, little is known about its impact on host-associated microbiomes in mariculture.

Dissecting modular synthases through inhibition: A complementary chemical and genetic approach.

Modular synthases, such as fatty acid, polyketide, and non-ribosomal peptide synthases (NRPSs), are sophisticated machineries essential in both primary and secondary metabolism. Various techniques have been developed to understand their genetic background and enzymatic abilities. However, uncovering the actual biosynthetic pathways remains challenging.

Bacterial Candidates for Colonization and Degradation of Marine Plastic Debris.

With the rising plastic pollution in the oceans, research on the plastisphere-the microorganisms interacting with marine plastic debris-has emerged. Microbial communities colonizing plastic have been characterized from several ocean regions and they are distinct from the communities of the surrounding waters, and a few plastic-degrading microorganisms have been isolated from other environments. Therefore, we propose that marine microorganisms have adapted to plastic as a surface for colonization and potentially degradation.

Marine Proteobacteria as a source of natural products: advances in molecular tools and strategies.

Covering: up to 2019Humanity is in dire need for novel medicinal compounds with biological activities ranging from antibiotic to anticancer and anti-dementia effects. Recent developments in genome sequencing and mining have revealed an unappreciated potential for bioactive molecule production in marine Proteobacteria. Also, novel bioactive compounds have been discovered through molecular manipulations of either the original marine host bacteria or in heterologous hosts.