Analysis of Bacterial Communities on North Sea Macroalgae and Characterization of the Isolated Planctomycetes Adhaeretor mobilis gen. nov., sp. nov., Roseimaritima multifibrata sp. nov., Rosistilla ulvae sp. nov. and Rubripirellula lacrimiformis sp. nov.

Abstract

Planctomycetes are bacteria that were long thought to be unculturable, of low abundance, and therefore neglectable in the environment. This view changed in recent years, after it was shown that members of the phylum Planctomycetes can be abundant in many aquatic environments, e.g., in the epiphytic communities on macroalgae surfaces. Here, we analyzed three different macroalgae from the North Sea and show that Planctomycetes is the most abundant bacterial phylum on the alga Fucus sp., while it represents a minor fraction of the surface-associated bacterial community of Ulva sp. and Laminaria sp. Especially dominant within the phylum Planctomycetes were Blastopirellula sp., followed by Rhodopirellula sp., Rubripirellula sp., as well as other Pirellulaceae and Lacipirellulaceae, but also members of the OM190 lineage. Motivated by the observed abundance, we isolated four novel planctomycetal strains to expand the collection of species available as axenic cultures since access to different strains is a prerequisite to investigate the success of planctomycetes in marine environments. The isolated strains constitute four novel species belonging to one novel and three previously described genera in the order Pirellulales, class Planctomycetia, phylum Planctomycetes.

Changes in the Rhizosphere Prokaryotic Community Structure of Halodule wrightii Monospecific Stands Associated to Submarine Groundwater Discharges in a Karstic Costal Area

“…Conversely, sites S5 and S6 were clustered apart. Acidobacteria ( Subgroup 9 class and Subgroup 10 genus), Bacteroidetes ( SJA-28 order, Aquibacter and Portibacter genus) and Planctomycetes ( Rubripirellula genus ) were more abundant for these sites ( Figure 5 ), which have been reported as important players in marine nutrient cycling due to the degradation of complex organic matter [ 3 , 63 , 64 ]. This is supported by the positive correlations obtained between organic matter and Planctomycetacia and the fact that higher organic matter contents were obtained for these sites.…”

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

“…The first described species in the family was Bythopirellula goksoeyrii [25, 26] and the type genus/species is Lacipirellula/Lacipirellula parvula [24]. In the last 2 years, additional novel taxa were described and the family currently comprises 13 species and 8 genera [22]: Bythopirellula , Lacipirellula , Aeoliella , Posidoniimonas , Botrimarina , Adhaeretor , Pseudobythopirellula and Pirellulimonas [24–29]. These include freshwater species (genus Lacipirellula ) [24, 29] and marine-associated ones, retrieved from a variety of environments such as hydrothermal areas, seawater, iron-hydroxide deposits and associated with the biofilms of Posidonia oceanica and the alga Laminaria sp.…”

“…These include freshwater species (genus Lacipirellula) [24,29] and marine-associated ones, retrieved from a variety of environments such as hydrothermal areas, seawater, iron-hydroxide deposits and associated with the biofilms of Posidonia oceanica and the alga Laminaria sp. [27,28].…”

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

“…The phylum Planctomycetota [1] is formed of bacteria that inhabit a wide range of environments, such as marine, terrestrial, freshwater and extreme ones (like hot springs or hydrothermal vents) or in association with other organisms such as macroalgae or invertebrates [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Planctomycetes are highly diverse and complex regarding their cell biology and structure [4,[17][18][19][20].…”