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.

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., 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.

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.