Pseudomonas litoralis sp. nov., isolated from Mediterranean seawater

Abstract

Strains 2SM5 T and 2SM6, two strictly aerobic chemo-organotrophic gammaproteobacteria, were isolated from Mediterranean seawater off the coast of Vinaroz, Castelló n, Spain, in February, 1990. They were extensively characterized by a polyphasic study that placed them in the genus Pseudomonas. Phylogenetic analysis of 16S rRNA gene sequences showed that both strains shared 100 % sequence similarity and were closely related to members of the Pseudomonas pertucinogena clade, with less than 97.3 % similarity to strains of established species; Pseudomonas xiamenensis was the closest relative. Analysis of sequences of three housekeeping genes, rpoB, rpoD and gyrB, further confirmed the phylogenetic assignment of the Mediterranean isolates. Chemotaxonomic traits such as quinone and polar lipid composition also corroborated the placement of strains 2SM5 T and 2SM6 in the gammaproteobacteria. Other phenotypic traits, including fatty acid composition, enabled clear differentiation of both isolates from other species of Pseudomonas. We therefore conclude that strains 2SM5 T and 2SM6 represent a novel species of Pseudomonas, for which the name Pseudomonas litoralis is proposed; the type strain is 2SM5 T (5CECT 7670 T 5KCTC 23093 T ).The genus Pseudomonas Migula 1894 was described originally to include Gram-negative, strictly aerobic rods that are motile by polar flagella. Pseudomonas includes a large number of species isolated from a variety of natural sources including soil, plants, water and clinical specimens, and has become a very heterogeneous taxon that is characterized by a high level of metabolic diversity (Rosselló et al., 1991;Palleroni, 2005).With the application of modern taxonomic techniques, including rRNA-DNA hybridization studies (Palleroni, 1984) and phylogenetic studies based on 16S rRNA gene sequence comparisons (Moore et al., 1996;Anzai et al., 2000), the genus Pseudomonas has been split into several genera, some even belonging to different subclasses in the phylum 'Proteobacteria', to accommodate bacteria originally described as species of Pseudomonas. In spite of this, the genus Pseudomonas sensu stricto comprises 120 species with names that have been validly published (http://www. bacterio.cict.fr; Yarza et al., 2010). Based on partial sequences of four housekeeping genes (16S rRNA, gyrB, rpoB and rpoD), Mulet et al. (2010) have recently identified two main intrageneric groups (IG) among species of the genus Pseudomonas, called IG Pseudomonas aeruginosa and IG Pseudomonas fluorescens. In their study, some species were placed on phylogenetic branches apart from both lineages, namely Pseudomonas oryzihabitans, Pseudomonas psychrotolerans, Pseudomonas luteola, Pseudomonas pertucinogena and Pseudomonas pachastrellae; among them, the last two always formed the deepest branch. Although not considered in the study by Mulet et al. (2010), other recently described species closely related to P. pertucinogena (Kawai & Yabuuchi, 1975) and P. pachastrellae (Romanenko et al., 2005) (Palleroni, 2005), three of thes...

Pseudomonas formosensis sp. nov., a gamma-proteobacteria isolated from food-waste compost in Taiwan

“…Identification and comparison were made by using the Aerobe (RTSBA6) database of the MIDI System (Sherlock version 6.0). Malic acid was similar to that of P. pertucinogena ATCC 190 T with respect to the presence of diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE) and phosphatidylglycerol (PG), which is in agreement with data published previously for species of the genus Pseudomonas (Pascual et al, 2012). In addition, a moderate amount of phosphatidylcholine (PC) was also detected irrespective of some quantitative difference in the two strains (Fig.…”

Pseudomonas hussainii sp. nov., isolated from droppings of a seashore bird, and emended descriptions of Pseudomonas pohangensis, Pseudomonas benzenivorans and Pseudomonas segetis

“…Both strains contained ubiquinone 9 (Q-9) as the major respiratory quinone, similar to quinone data reported previously from species of the genus Pseudomonas (Liu et al, 2013;Lin et al, 2013a, b;Feng et al, 2012;Pascual et al, 2012;Weon et al, 2006;Hauser et al, 2004).…”

“…Members of the genus Pseudomonas are ubiquitous in distribution, and have been isolated from various sources such as water (Liu et al, 2013;Pascual et al, 2012;Lang et al, 2010;Hauser et al, 2004), soil (Lin et al, 2013a;Feng et al, 2012;Park et al, 2006), seashore sand (Weon et al, 2006) and food-waste compost (Lin et al, 2013b). The nutritional studies of Stanier et al (1966) on Pseudomonas provided baseline assistance to the phenotypic characterization of representative isolates.…”

Pseudomonas populi sp. nov., an endophytic bacterium isolated from Populus euphratica

“…TLC plates were stained with 10 % molybdophosphoric acid to detect all the lipids and further characterized by spraying with molybdenum blue (specific for phosphates), a-naphthol (specific for sugars) and ninhydrin (specific for amino groups). Strain KBL-4-9 T exhibited a polar lipid profile consisting of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and three unidentified phospholipids, which is in agreement with data published previously for species of the genus (Pascual et al, 2012) (Fig. S5).…”

“…They have a variety of functions related to the decomposition of organic substances as well as promotion of plant growth and they can also act as pathogens (Peix et al, 2009). There are currently more than 120 species of the genus Pseudomonas with validly published names (Pascual et al, 2012). Previously (Palleroni, 1984), members of the genus Pseudomonas were scattered throughout the classes Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria, but they are now restricted to the class Gammaproteobacteria; the members of the classes Alphaproteobacteria and Betaproteobacteria were transferred to other genera (Kersters et al, 1996).…”