Taxonomic study of Marinomonas strains isolated from the seagrass Posidonia oceanica, with descriptions of Marinomonas balearica sp. nov. and Marinomonas pollencensis sp. nov.

Abstract

Novel aerobic, Gram-negative bacteria with DNA G+C contents below 50 mol% were isolated from the culturable microbiota associated with the Mediterranean seagrass Posidonia oceanica. 16S rRNA gene sequence analyses revealed that they belong to the genus Marinomonas. Strain IVIA-Po-186 is a strain of the species Marinomonas mediterranea, showing 99.77 % 16S rRNA gene sequence similarity with the type strain, MMB-1T, and sharing all phenotypic characteristics studied. This is the first description of this species forming part of the microbiota of a marine plant. A second strain, designated IVIA-Po-101T, was closely related to M. mediterranea based on phylogenetic studies. However, it differed in characteristics such as melanin synthesis and tyrosinase, laccase and antimicrobial activities. In addition, strain IVIA-Po-101T was auxotrophic and unable to use acetate. IVIA-Po-101T shared 97.86 % 16S rRNA gene sequence similarity with M. mediterranea MMB-1T, but the level of DNA–DNA relatedness between the two strains was only 10.3 %. On the basis of these data, strain IVIA-Po-101T is considered to represent a novel species of the genus Marinomonas, for which the name Marinomonas balearica sp. nov. is proposed. The type strain is IVIA-Po-101T (=CECT 7378T =NCIMB 14432T). A third novel strain, IVIA-Po-185T, was phylogenetically distant from all recognized Marinomonas species. It shared the highest 16S rRNA gene sequence similarity (97.4 %) with the type strain of Marinomonas pontica, but the level of DNA–DNA relatedness between the two strains was only 14.5 %. A differential chemotaxonomic marker of this strain in the genus Marinomonas is the presence of the fatty acid C17 : 0 cyclo. Strain IVIA-Po-185T is thus considered to represent a second novel species of the genus, for which the name Marinomonas pollencensis sp. nov. is proposed. The type strain is IVIA-Po-185T (=CECT 7375T =NCIMB 14435T). An emended description of the genus Marinomonas is given based on the description of these two novel species, as well as other Marinomonas species described after the original description of the genus.

A diverse group of halophilic bacteria exist in Lunsu, a natural salt water body of Himachal Pradesh, India

“…Marinomonas strain IVIA-Po-185T and M. pontica 46-16 have been isolated from the sea grass Posidonia oceanic . They are helical in shape, have salt tolerance up to 10% and grow at temperatures between 5–37°C and 4–33°C, respectively (Espinosa et al 2010). The halotolerant isolate Marinomonas sp.…”

Quorum Sensing and Quorum Quenching in the Mediterranean Seagrass Posidonia oceanica Microbiota

“…However, similar bacteria lineages were also found in epiphytic bacterial communities of seaweeds (Egan et al, 2013) and in the core microbiota of seagrass roots, which appears dominated by Gammaproteobacteria (Egan et al, 2013) represented in our study by three strains affiliated with Marinomonas posidonica, and one strain affiliated with M. mediterranea. Previous studies revealed that microorganisms within the genus Marinomonas can be readily isolated from the different tissues of P. oceanica (Espinosa et al, 2010;Lucas-Elio et al, 2011), including Marinomonas balnearica, pollencensis, mediterranea, and posidonica. Marinomonas posidonica is frequently detected in the microbiota of P. oceanica, and some authors suggest an ancient relationship between these two species (Lucas-Elio et al, 2011), including the bacteria promoting the growth of the angiosperm (Celdran et al, 2012).…”

Regulation of the Marinomonas mediterranea Antimicrobial Protein Lysine Oxidase by l -Lysine and the Sensor Histidine Kinase PpoS

“…The natural inducer may well be L-Lys, since it is the substrate of the enzyme, while the others would act simply because of the striking structural similarity of all these compounds containing a side chain with at least three carbons and an amino group. M. mediterranea is a component of the microbiota associated with the marine plant Posidonia oceanica (12). One possibility is that the presence of L-Lys reflects an environment in close proximity to the plant that would release the amino acid.…”

“…The melanogenic marine bacterium Marinomonas mediterranea is a component of the microbiota of the marine plant Posidonia oceanica, which is of great importance in Mediterranean Sea ecosystems (12). It synthesizes an antimicrobial protein that was initially named marinocine and was later named LodA (24,25).…”