The influence of the phylum Planctomycetota in the environmental resistome.

Antimicrobial resistance is one of the leading causes of death worldwide and research on this topic has been on the spotlight for a long time. More recently and in agreement with the One Health Approach, the focus has moved towards the environmental resistome. Members of the phylum Planctomycetota are ubiquitously present in the environment including in hotspots for antimicrobial resistance selection and dissemination.

Uncovering the biotechnological capacity of marine and brackish water Planctomycetota.

An appealing strategy for finding novel bioactive molecules in Nature consists in exploring underrepresented and -studied microorganisms. Here, we investigated the antimicrobial and tumoral anti-proliferative bioactivities of twenty-three marine and estuarine bacteria of the fascinating phylum Planctomycetota. This was achieved through extraction of compounds produced by the Planctomycetota cultured in oligotrophic medium followed by an antimicrobial screening against ten relevant human pathogens including Gram-positive and Gram-negative bacteria, and fungi.

Unveiling the bioactive potential of Actinomycetota from the Tagus River estuary.

The increase in global travel and the incorrect and excessive use of antibiotics has led to an unprecedented rise in antibiotic resistance in bacterial and fungal populations. To overcome these problems, novel bioactive natural products must be discovered, which may be found in underexplored environments, such as estuarine habitats. In the present work, estuarine actinomycetotal strains were isolated with conventional and iChip techniques from the Tagus estuary in Alcochete, Portugal, and analysed for different antimicrobial bioactivities.

sp. nov., a member of the from marine beach sediment of the north coast of Portugal.

The oceans harbour a myriad of unknown micro-organisms that remain unstudied because of a failure to establish the right growth conditions under laboratory conditions. To overcome this limitation, an isolation effort inspired by the iChip was performed using marine sediments from Memória beach, Portugal. A novel strain, PMIC_1C1B, was obtained and subjected to a polyphasic study.

Stieleria tagensis sp. nov., a novel member of the phylum Planctomycetota isolated from Tagus River in Portugal.

A bacterial strain was isolated from a brackish water sample of Tagus river, Alcochete, Portugal and was designated TO1_6. It forms light pink colonies on M13 medium supplemented with N-acetylglucosamine. Cells are pear-shaped to spherical, form rosettes and divide by budding.

sp. nov., isolated from marine beach sediment.

A novel actinomycetal strain, designated M600PL45_2, was isolated from marine sediments obtained from Ingleses beach, Porto, on the Northern Coast of Portugal and was subjected to a polyphasic taxonomic characterisation study. The here described Gram-reaction-positive strain is characterised by the production of a brown pigment in both solid and liquid medium and forms typical helical hyphae that differentiate into smooth spores. The results of a phylogenetic analysis based on the 16S rRNA gene sequence indicated that M600PL45_2 has a high similarity to two members of the genus , ASO4wet (98.

sp. nov. isolated from brackish water of the Tagus estuary in Alcochete, Portugal.

An isolation effort focused on sporogenous from the Tagus estuary in Alcochete, Portugal, yielded a novel actinomycetal strain, designated MTZ3.1, which was subjected to a polyphasic taxonomic study. MTZ3.

Microbiological quality, antibiotic resistant bacteria and relevant resistance genes in ready-to-eat Pacific oysters (Magallana gigas).

Oysters are a highly valued seafood but can endanger public health, if they are eaten raw or barely cooked. We evaluated the microbiological quality of Pacific oysters (Magallana gigas) by international standard methods in four groups (each with four to five animals) acquired from supermarkets and directly from a farm producer. Most of the groups presented satisfactory microbiological quality.

sp. nov., a novel member of the phylum with an unusual filamentous structure.

Organisms with distinctive biological features and cellular organization constitute the bacterial phylum . In this study, we formally describe a novel isolate, strain ICT_H6.2, isolated from sediment samples collected in the brackish environment of the Tagus River estuary (Portugal) using an iChip-based culturing technique.

sp. nov., a Novel Member of the Family with Antimicrobial Activity Isolated in Portugal from Brackish Sediments.

The phylum is known for having uncommon biological features. Recently, biotechnological applications of its members have started to be explored, namely in the genus . Here, we formally describe a novel isolate designated as strain ICT_E10.

Rhodopirellula aestuarii sp. nov., a novel member of the genus Rhodopirellula isolated from brackish sediments collected in the Tagus River estuary, Portugal.

Bacteria within the phylum Planctomycetota are biologically relevant due to unique characteristics among prokaryotes. Members of the genus Rhodopirellula can be abundant in marine habitats, however, only six species are currently validly described. In this study, we expand the explored genus diversity by formally describing a novel species.

Does a Diet Rich in the Bacterium Improve Performance?

Background: In the wild various organisms contribute to daphnids diet. This study, intendeds to evaluate the potential of the concentration of as a single or supplementary food source for .

Methods: Feeding assays were performed according to standard guidelines for chronic assays (21 days), and life-history parameters and several biomarkers (protein content, oxidative stress, energetic reserves and pigments) were measured.

iChip-Inspired Isolation, Bioactivities and Dereplication of from Portuguese Beach Sediments.

Oceans hold a stunning number of unique microorganisms, which remain unstudied by culture-dependent methods due to failures in establishing the right conditions for these organisms to grow. In this work, an isolation effort inspired by the iChip was performed using marine sediments from Memoria beach, Portugal. The isolates obtained were identified by 16S rRNA gene analysis, fingerprinted using BOX-PCR and ERIC-PCR, searched for the putative presence of secondary metabolism genes associated with polyketide synthase I (PKS-I) and non-ribosomal peptide synthetases (NRPS), screened for antimicrobial activity against ATCC 25922 and ATCC 29213, and had bioactive extracts dereplicated by LC/HRMS.

Culturomics remains a highly valuable methodology to obtain rare microbial diversity with putative biotechnological potential from two Portuguese salterns.

Background: The high salt concentration is the major factor limiting microbial growth at salterns, along with solar radiation, temperature, and pH. These environmental factors play key roles in the acquisition of unique genetic adaptations for the survival of microorganisms in salterns, which can result in the production of interesting secondary metabolites. The main goal of the present work was to isolate and compare the culturable microbiota from two geographically distant salterns in Portugal and access their biotechnological potential.

Isolation, diversity and antimicrobial activity of planctomycetes from the Tejo river estuary (Portugal).

The discovery of new bioactive compounds is an invaluable aid to the development of new drugs. Strategies for finding novel molecules can focus on the exploitation of less studied organisms and ecosystems such as planctomycetes and brackish habitats. The unique cell biology of the underexplored Planctomycetota mean it is of particular interest.

sp. nov., a novel planctomycete isolated from marine sediments collected in the Portuguese north coast.

The phylum is constituted by bacteria with unique features that are well adapted to a vast range of habitats. Here, we describe a novel planctomycete isolated from marine sediments collected on a beach in Matosinhos (Portugal) using an iChip-based culturing technique. Strain ICM_H10 forms beige-coloured colonies in modified M14 medium and its cells are spherical to ovoid in shape, stalked, rosette-forming and showing motility in a phase of the life cycle.

The Planctomycetia: an overview of the currently largest class within the phylum Planctomycetes.

The phylum Planctomycetes comprises bacteria with uncommon features among prokaryotes, such as cell division by budding, absence of the bacterial tubulin-homolog cell division protein FtsZ and complex cell plans with invaginations of the cytoplasmic membrane. Although planctomycetes are ubiquitous, the number of described species and isolated strains available as axenic cultures is still low compared to the diversity observed in metagenomes or environmental studies. An increasing interest in planctomycetes is reflected by the recent description of a large number of new species and their increasing accessibility in terms of pure cultures.

Novel and Conventional Isolation Techniques to Obtain Planctomycetes from Marine Environments.

Bacteria from the distinctive phylum are well spread around the globe; they are capable of colonizing many habitats, including marine, freshwater, terrestrial, and even extreme habitats such as hydrothermal vents and hot springs. They can also be found living in association with other organisms, such as macroalgae, plants, and invertebrates. While ubiquitous, only a small fraction of the known diversity includes axenic cultures.

Comparison of neutral lipid fatty acid composition in organisms from different trophic levels.

The profiles of total fatty acids (TFAs) and the neutral lipid fatty acids (NLFAs) were compared for the bacterium Rhodopirellula rubra and the alga Raphidocelis subcapitata (conventional food source for Daphnia magna). D. magna NLFAs were assessed when this crustacean was fed with bacterium and alga, individually or in combination.

Bremerella alba sp. nov., a novel planctomycete isolated from the surface of the macroalga Fucus spiralis.

A bacterial strain, designated FF15, was isolated from the thallus surface of the macroalga Fucus spiralis sampled on a rocky beach in Porto, Portugal. Based on the 16S rRNA gene sequence, strain FF15 was affiliated to the phylum Planctomycetes. This strain forms white colonies on modified M13 medium and the cells are pear-shaped, can form rosettes, divide by polar budding and are motile.

as a Vital Constituent of the Microbial Communities Inhabiting Different Layers of the Meromictic Lake Sælenvannet (Norway).

Meromictic lakes are permanently stratified lakes that display steep gradients in salinity, oxygen and sulphur compounds tightly linked to bacterial community structure and diversity. Lake Sælenvannet is a meromictic lake located south of Bergen, Norway. The 26 m deep lake is connected to the open sea and permanently stratified into two layers separated by a chemocline.

Ecotoxicological evaluation of fungicides used in viticulture in non-target organisms.

The effect of fungicides, commonly used in vine cultures, on the health of terrestrial and aquatic ecosystems has been poorly studied. The objective of this study was to evaluate the toxicity of three viticulture fungicides (myclobutanil, cymoxanil, and azoxystrobin) on non-target organisms, the bacteria Rhodopirellula rubra, Escherichia coli, Pseudomonas putida, and Arthrobacter sp., the microalgae Raphidocelis subcapitata, and the macrophyte Lemna minor.