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Skeletonema costatum , a cosmopolitan diatom primarily inhabiting coastal ecosystems, exhibits a typically close yet variable relationship with heterotrophic bacteria. The increasing temperature of surface seawater is expected to substantially affect the viability and ecological dynamics of S. costatum , potentially altering its relationship with bacteria. However, it remains unclear to what extent the elevated temperature could change these relationships. Here, the relationship between axenic S. costatum and natural seawater bacteria underwent a dramatic shift from mutualism to antagonism as the co-culture temperature increased from 20°C to 25°C. The co-occurrence network indicated significantly increased complexity of interaction between S. costatum and bacteria community after temperature elevation, especially with Flavobacteriaceae , implying their potential role in eliminating S. costatum under higher temperatures. Additionally, a Flavobacteriaceae isolate, namely MS1 identified as Tamlana genus, was isolated from the co-culture system at 25°C. MS1 had a remarkable ability to eliminate S. costatum , with the mortality rate at 25°C steadily rising from 30.2% at 48 h to 92.4% at 120 h. However, it promoted algal growth to some extent at 20°C. These results demonstrated that increased temperature promotes MS1 shifts from mutualism to antagonism with S. costatum . According to the comparative genomics analysis, changes in the lifestyle of MS1 were attributed to the increased gliding motility and attachment of MS1 under elevated temperature, enabling it to exert an algicidal effect through direct contact with alga. This investigation provided an advanced understanding of interactions between phytoplankton and bacteria in future warming oceanic ecosystems., Importance: Ocean warming profoundly influences the growth and metabolism of phytoplankton and bacteria, thereby significantly reshaping their interactions. Previous studies have shown that warming can change bacterial lifestyle from mutualism to antagonism with phytoplankton, but the underlying mechanism remains unclear. In this study, we found that high temperature promotes Tamlana sp. MS1 adhesion to Skeletonema costatum , leading to algal lysis through direct contact, demonstrating a transition in lifestyle from mutualism to antagonism with increasing temperature. Furthermore, the gliding motility of MS1 appears to be pivotal in mediating the transition of its lifestyle. These findings not only advance our understanding of the phytoplankton-bacteria relationship under ocean warming but also offer valuable insights for predicting the impact of warming on phytoplankton carbon sequestration., Competing Interests: The authors declare no conflict of interest.

Background: Vector-borne pathogens must survive and replicate in the hostile environment of an insect's midgut before successful dissemination. Midgut microbiota interfere with pathogen infection by activating the basal immunity of the mosquito and by synthesizing pathogen-inhibitory metabolites., Methods: The goal of this study was to assess the influence of Zika virus (ZIKV) infection and increased temperature on Aedes albopictus midgut microbiota. Aedes albopictus were reared at diurnal temperatures of day 28 °C/night 24 °C (L) or day 30 °C/night 26 °C (M). The mosquitoes were given infectious blood meals with 2.0 × 10 8 PFU/ml ZIKV, and 16S rRNA sequencing was performed on midguts at 7 days post-infectious blood meal exposure., Results: Our findings demonstrate that Elizabethkingia anophelis albopictus was associated with Ae. albopictus midguts exposed to ZIKV infectious blood meal. We observed a negative correlation between ZIKV and E. anophelis albopictus in the midguts of Ae. albopictus. Supplemental feeding of Ae. albopictus with E. anophelis aegypti and ZIKV resulted in reduced ZIKV infection rates. Reduced viral loads were detected in Vero cells that were sequentially infected with E. anophelis aegypti and ZIKV, dengue virus (DENV), or chikungunya virus (CHIKV)., Conclusions: Our findings demonstrate the influence of ZIKV infection and temperature on the Ae. albopictus microbiome along with a negative correlation between ZIKV and E. anophelis albopictus. Our results have important implications for controlling vector-borne pathogens., (© 2021. The Author(s).)

Polyphasic taxonomic analysis was performed on a novel bacterium, designated UR159 T , isolated in 2016 from human blood of a septic patient hospitalized in France. Preliminary 16S rRNA gene sequence-based phylogenetic analysis indicated that strain UR159 T belonged to the family Flavobacteriaceae, forming a distinct phyletic line distantly related (<94% sequence similarity) to known species of the family. Further phenotypic, chemotaxonomic and genomic analyses were performed. Cells were non-motile, oxidase-negative, catalase-positive Gram-negative rods. It was strictly aerobic yielding yellow-pigmented colonies, and was metabolically rather inert. Major fatty acids were iso-branched fatty acids, predominantly iso-C 15:0 (55.5%) and iso-C 17:1 ω9c (8.8%). Whole genome sequencing revealed a 2.3-Mbp genome encoding a total of 2262 putative genes with a genomic DNA G+C content at 37.6mol%. The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (isDDH) values between strain UR159 T and the most closely related members of the Flavobacteriaceae family were <75% and <39%, respectively, much below the established cut-offs for ANI (<95-96%) and isDDH (<70%) for species and genus delineation. Average Amino Acid Identity (AAI) percentages were also estimated and were lower than 65% (cut-off proposed for genus delineation for uncultivated prokaryotes) in all cases, except for F. marinum that was just at the limit (65.1%). Based on these findings, we propose it as a new genus and species, Avrilella dinanensis gen. nov., sp. nov. (type strain UR159 T =CIP 111616 T =DSM 105483 T )., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Mass mortality due to necrosis signs occurred in hatchery-reared zoea stage larvae of the mud crab Scylla serrata in Okinawa, Japan, and a causative bacterium was isolated. In this study, we identified and characterized the bacterium by genome analysis, biochemical properties and pathogenicity. The bacterium was a Gram-negative, non-motile, long rod, forming yellow colonies on a marine agar plate. It grew at 20-33°C (not at 37°C) and degraded chitin and gelatin. Phylogenetic analysis of the 16S rRNA gene sequence identified the bacterium as Aquimarina hainanensis. Genome sequence data obtained from Illumina MiSeq generated 29 contigs with 3.56 Mbp in total length and a G + C content of 32.5%. The predicted 16 chitinase genes, as putative virulence factors, had certain homologies with those of genus Aquimarina. Experimental infection with the bacterium conducted on larvae of four crustacean species, brine shrimp Artemia franciscana, freshwater shrimp Caridina multidentata, swimming crab Portunus trituberculatus and mud crab S. serrata, revealed that this bacterium was highly virulent to these species. The present study suggests that the bacterium caused mass mortality in mud crab seed production was A. hainanensis and can be widely pathogenic to crustaceans., (© 2020 John Wiley & Sons Ltd.)

The aim of the present study was to characterize two gram-negative bacterial strains that were isolated from diseased Atlantic Horse Mackerel Trachurus trachurus in 2017. Based on the results obtained from the biochemical and chemotaxonomic characterization, the isolates were identified as Lacinutrix spp. The highest similarity of the 16S rRNA gene sequences was obtained with the strain L. venerupis CECT 8573 T (99.1%), while other species showed similarities of 98% (L. jangbogonensis) and 97% (L. algicola and L. mariniflava). Molecular characterization by repetitive element (REP)-PCR and enterobacterial repetitive intergenic consensus (ERIC)-PCR, as well as proteomic characterization by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS), demonstrated heterogeneity between the strains from the Atlantic Horse Mackerel and the type strain, CECT 8573 T . The virulence of one of the isolates for Turbot Scophthalmus maximus, European Sea Bass Dicentrarchus labrax, Senegalese Sole Solea senegalensis, and Rainbow Trout Oncorhynchus mykiss was assessed under experimental conditions. No mortalities were recorded after intraperitoneal injections with high doses of bacteria (1 × 10 9  CFU/mL). Thus, further studies are necessary to elucidate the impact of this bacterial species as a fish pathogen., (© 2019 American Fisheries Society.)

Microalgae and bacteria are known to be closely associated in diverse environments. To isolate dominant bacterial species associated with a green alga, Dunaliella tertiolecta, a photoreactor culture of the microalga was investigated using culture-based and culture-independent approaches. The bacterial community structure of the algal culture showed that the most abundant bacterial species under the culture conditions was related to the genus Winogradskyella. The closely related amplicon sequences, showing ≥ 99.5% 16S rRNA gene sequence similarity to one of the isolates, designated IMCC-33238 T , constituted > 49% of the bacterial community and was therefore regarded as the most dominant species in the algal culture. Strain IMCC33238 T was characterized by Gramstaining-negative and orange-colored rods. Phylogenetic analyses of the 16S rRNA genes as well as whole genome sequences revealed that strain IMCC33238 T belonged to Winogradskyella and shared more than 97.2% 16S rRNA gene sequence similarity with Winogradskyella species. The strain contained iso-C 15:1 G, iso-C 15:0 , iso-C 15:0 3-OH, and summed feature 3 (C 16:1 ω6c and/or C 16:1 ω7c) as major fatty acids and MK-6 as the predominant quinone. The polar lipids found in strain IMCC33238 T were phosphatidylethanolamine, two unidentified aminolipids, and three unidentified lipids. The genome of strain IMCC33238 T was 3.37 Mbp in size with 33.9 mol% G + C content and proteorhodopsin. Many genes encoding folate and vitamin production are considered to play an important role in the bacteria-algae interaction. On the basis of phylogenetic and phenotypic characteristics, strain IMCC33238 T represents a novel species in the genus Winogradskyella, for which the name Winogradskyella algicola sp. nov. is proposed. The type strain is IMCC33238 T (= KACC 21192T = NBRC 113704 T ).

Most species of the genus Elizabethkingia are pathogenic to humans and animals, most commonly causing meningitis. However, our understanding of the pathogenic mechanisms involved is poor and there have been few pathological studies of Elizabethkingia spp. in animals. To understand the host injury induced by Elizabethkingia spp., we established a model of E. miricola infection in the black-spotted frog ( Pelophylax nigromaculatus ). The systematic pathology in and oxidative damage in the infection model were investigated. Our results show that recently isolated E. miricola is a bacterium that mainly parasitizes the host brain and that neurogenic organs are the predominant sites of damage. Infection mainly manifested as severe brain abscesses, meningoencephalitis, necrotic spondylitis, and necrotic retinitis. The liver, spleen, kidney, gastrointestinal tract, and lung were also affected to varying degrees, with bacterial necrotic inflammation. P. nigromaculatus also suffered enormous damage to its oxidative system during E. miricola infection, which may have further aggravated its disease state. Our results provide a preliminary reference for the study and treatment of Elizabethkingia spp. - induced neurological diseases in animals., Competing Interests: The authors declare that they have no conflict of interests., (Copyright © 2019 Xiaoli Huang et al.)

A Gram-stain negative, rod-shaped and non-flagellated bacterium, designated strain 1Q3 T , was isolated from coastal seawater in Xiamen Island, China, and subjected to taxonomic characterisation using a polyphasic approach. Strain 1Q3 T was found to be aerobic, non-gliding and to lack flexirubin-type pigments. Catalase activity was found to be negative and oxidase positive. The strain has the ability to degrade protein. The nearly complete 16S rRNA gene sequence of strain 1Q3 T shows high sequence similarities with Nonlabens aestuariivivens OITF-31 T (96.1%), Nonlabens halophilus CAU 1131 T and Nonlabens spongiae UST030701-156 T (95.7% and 95.5%, respectively). Phylogenetic analysis based on 16S rRNA gene sequences and phylogenomic analysis based on a 92 bacterial core gene set indicated that strain 1Q3 T should be affiliated to the genus Nonlabens, but forms a distinct monophyletic branch, which is separated from the other members within the genus Nonlabens. The predominant fatty acids (> 10%) were identified as iso-C 17:0 3-OH, iso-C 15:0 and anteiso-C 15:0 . The predominant respiratory quinone was found to be MK-6. The polar lipids were identified as phosphatidylethanolamine, a phospholipid, an aminolipid and three unidentified polar lipids. The draft genome size of strain 1Q3 T is 3.7 Mb with genomic G + C content of 41.1 mol%. Based on these results, strain 1Q3 T is concluded to represent a novel species within the genus Nonlabens, for which the name Nonlabens xiamenensis sp. nov. is proposed with the type strain 1Q3 T (= MCCC 1A14023 T  = KCTC 62889 T ).

Growing demands for bio-friendly antifouling surfaces have stimulated the development of new and ever-improving material paradigms. Despite notable progress in bio-friendly coatings, the biofouling problem remains a critical challenge. In addition to biofouling characteristics, mechanically stressed surfaces such as ship hulls, piping systems, and heat exchangers require long-term durability in marine environments. Here, we introduce a new generation of anti-biofouling coatings with superior characteristics and high mechanical, chemical and environmental durability. In these surfaces, we have implemented the new physics of stress localization to minimize the adhesion of bio-species on the coatings. This polymeric material contains dispersed organogels in a high shear modulus matrix. Interfacial cavitation induced at the interface of bio-species and organogel particles leads to stress localization and detachment of bio-species from these surfaces with minimal shear stress. In a comprehensive study, the performance of these surfaces is assessed for both soft and hard biofouling including Ulva, bacteria, diatoms, barnacles and mussels, and is compared with that of state-of-the-art surfaces. These surfaces show Ulva accumulation of less than 1%, minimal bacterial biofilm growth, diatom attachment of 2%, barnacle adhesion of 0.02 MPa and mussel adhesion of 7.5 N. These surfaces promise a new physics-based route to address the biofouling problem and avoid adverse effects of biofouling on the environment and relevant technologies.

Plankton communities consist of complex microbial consortia that change over time. These fluctuations can be only partially explained by limiting resources. Biotic factors such as herbivores and pathogens also contribute to the control of algal blooms. Here we address the effects of algicidal bacteria on a natural plankton community in an indoor enclosure experiment. The algicidal bacteria, introduced into plankton taken directly from the North Sea during a diatom bloom, caused the rapid decline of the bloom-forming Chaetoceros socialis within only 1 day. The haptophyte Phaeocystis , in contrast, is resistant to the lytic bacteria and could benefit from the removal of the competitor, as indicated by an onset of a bloom in the treated enclosures. This cascading effect caused by the bacterial pathogen accelerated the succession of Phaeocystis , which bloomed with a delay of only several weeks in the in situ waters at Helgoland Roads in the North Sea. The algicidal bacteria can thus modulate the community within the limits of the abiotic and biotic conditions of the local environment. Implications of our findings for plankton ecosystem functioning are discussed. IMPORTANCE Plankton communities change on a seasonal basis in temperate systems, with distinct succession patterns; this is mainly due to algal species that have their optimal timing relative to environmental conditions. We know that bacterial populations are also instrumental in the decay and termination of phytoplankton blooms. Here, we describe algicidal bacteria as modulators of this important species succession. Upon treatment of a natural plankton consortium with an algicidal bacterium, we observed a strong shift in the phytoplankton community structure, compared to controls, resulting in formation of a succeeding Phaeocystis bloom. Blooms of this alga have a substantial impact on global biogeochemical and ecological cycles, as they are responsible for a substantial proportion of primary production during spring in the North Sea. We propose that one of the key factors influencing such community shifts may be algicidal bacteria., (Copyright © 2019 Bigalke et al.)

Interactions between photoautotrophs and heterotrophs are central to marine microbial ecosystems. Synechococcus are dominant marine phototrophs, and they are frequently associated with heterotrophic bacteria. These co-cultures provide a useful research system to investigate photoautotroph-heterotroph interactions in marine systems. Bacteria within the Roseobacter clade and Flavobacteria are two of the main bacterial lineages that exhibit intimate associations with Synechococcus populations. We conducted metagenomic analyses of a Synechococcus culture, followed by genomic binning of metagenomic contigs, and recovered five nearly complete genomes, including members of the Roseobacter clade (i.e. Marivita sp. XM-24) and Flavobacteria (i.e. Fluviicola sp. XM-24). Marivita sp. XM-24 is an ecological generalist of the Roseobacter clade and displays diverse metabolic capacities for the acquisition of nutrients and energy sources. Specifically, the genome contained numerous gene complements involved in the uptake and metabolism of nitrogen- and phosphorus-containing inorganic and organic compounds, in addition to the potential for aerobic anoxygenic photosynthesis, oxidation of carbon monoxide, inorganic sulfur oxidation, DMSP demethylation and PHA metabolism. The genome of the Flavobacteria representative, Fluviicola sp. XM-24, contained numerous peptidases, glycoside hydrolases, adhesion-related proteins and genes involved in gliding motility. Fluviicola sp. XM-24 likely specialize in the degradation of high molecular weight compound exudates from Synechococcus cells, including polysaccharides and polypeptides via attachment to particles, surfaces or cells. The distinct metabolic strategies identified within several heterotrophic bacteria that are associated with Syneochococcus cells provide insights into their lifestyles and nutrient utilization patterns, in addition to their interactions with photoautotrophs. Biological interactions, including mutualism, competition and antagonism, shape the microbial community structure of marine environments and are critical for understanding biogeochemical cycling in the ocean. These results provide valuable insights into the nature of interactions between dominant marine photoautotrophs and associated bacterial heterotrophs., (© FEMS 2019.)

The taxonomy of marine and non-marine organisms rarely overlap, but the mechanisms underlying this distinction are often unknown. Here, we predicted three major ocean-to-land transitions in the evolutionary history of Flavobacteriaceae, a family known for polysaccharide and peptide degradation. These unidirectional transitions were associated with repeated losses of marine signature genes and repeated gains of non-marine adaptive genes. This included various Na + -dependent transporters, osmolyte transporters and glycoside hydrolases (GH) for sulfated polysaccharide utilization in marine descendants, and in non-marine descendants genes for utilizing the land plant material pectin and genes facilitating terrestrial host interactions. The K + scavenging ATPase was repeatedly gained whereas the corresponding low-affinity transporter repeatedly lost upon transitions, reflecting K + ions are less available to non-marine bacteria. Strikingly, the central metabolism Na + -translocating NADH: quinone dehydrogenase gene was repeatedly gained in marine descendants, whereas the H + -translocating counterpart was repeatedly gained in non-marine lineages. Furthermore, GH genes were depleted in isolates colonizing animal hosts but abundant in bacteria inhabiting other non-marine niches; thus relative abundances of GH versus peptidase genes among Flavobacteriaceae lineages were inconsistent with the marine versus non-marine dichotomy. We suggest that phylogenomic analyses can cast novel light on mechanisms explaining the distribution and ecology of key microbiome components., (© 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Polysaccharide degradation by heterotrophic microbes is a key process within Earth's carbon cycle. Here, we use environmental proteomics and metagenomics in combination with cultivation experiments and biochemical characterizations to investigate the molecular details of in situ polysaccharide degradation mechanisms during microalgal blooms. For this, we use laminarin as a model polysaccharide. Laminarin is a ubiquitous marine storage polymer of marine microalgae and is particularly abundant during phytoplankton blooms. In this study, we show that highly specialized bacterial strains of the Bacteroidetes phylum repeatedly reached high abundances during North Sea algal blooms and dominated laminarin turnover. These genomically streamlined bacteria of the genus Formosa have an expanded set of laminarin hydrolases and transporters that belonged to the most abundant proteins in the environmental samples. In vitro experiments with cultured isolates allowed us to determine the functions of in situ expressed key enzymes and to confirm their role in laminarin utilization. It is shown that laminarin consumption of Formosa spp. is paralleled by enhanced uptake of diatom-derived peptides. This study reveals that genome reduction, enzyme fusions, transporters, and enzyme expansion as well as a tight coupling of carbon and nitrogen metabolism provide the tools, which make Formosa spp. so competitive during microalgal blooms.

A yellow pigmented bacterium designated strain MBLN094 T within the family Flavobacteriaceae was isolated from a halophyte Salicornia europaea on the coast of the Yellow Sea. This strain was a Gram-stain negative, aerobic, non-spore forming, rod-shaped bacterium. Phylogenetic analysis of the 16S rRNA gene sequence of strain MBLN094 T was found to be related to the genus Zunongwangia, exhibiting 16S rRNA gene sequence similarity values of 97.0, 96.8, 96.4, and 96.3% to Zunongwangia mangrovi P2E16 T , Z. profunda SM-A87 T , Z. atlantica 22II14-10F7 T , and Z. endophytica CPA58 T , respectively. Strain MBLN094 T grew at 20‒37°C (optimum, 25‒30°C), at pH 6.0‒10.0 (optimum, 7.0‒8.0), and with 0.5‒15.0% (w/v) NaCl (optimum, 2.0‒5.0%). Menaquinone MK-6 was the sole respiratory quinone. The polar lipids were phosphatidylethanolamine, two unidentified aminolipids, and four unidentified lipids. Major fatty acids were iso-C 17:0 3-OH, summed feature 3 (C 16:1 ω6c and/or C16:1 ω7c), and iso-C 15:0 . The genomic DNA G + C content was 37.4 mol%. Based on these polyphasic taxonomic data, strain MBLN094 T is considered to represent a novel species of the genus Zunongwangia, for which the name Zunongwangia flava sp. nov. is proposed. The type strain is MBLN094 T (= KCTC 62279 T = JCM 32262 T ).

Background: Pyropia yezoensis is an important marine crop which, due to its high protein content, is widely used as a seafood in China. Unfortunately, red rot disease, caused by Pythium porphyrae, seriously damages P. yezoensis farms every year in China, Japan, and Korea. Proteomic methods are often used to study the interactions between hosts and pathogens. Therefore, an iTRAQ-based proteomic analysis was used to identify pathogen-responsive proteins following the artificial infection of P. yezoensis with P. porphyrae spores., Results: A total of 762 differentially expressed proteins were identified, of which 378 were up-regulated and 384 were down-regulated following infection. A large amount of these proteins were involved in disease stress, carbohydrate metabolism, cell signaling, chaperone activity, photosynthesis, and energy metabolism, as annotated in the KEGG database. Overall, the data showed that P. yezoensis resists infection by inhibiting photosynthesis, and energy and carbohydrate metabolism pathways, as supported by changes in the expression levels of related proteins. The expression data are available via ProteomeXchange with the identifier PXD009363., Conclusions: The current data provide an overall summary of the red algae responses to pathogen infection. This study improves our understanding of infection resistance in P. yezoensis, and may help in increasing the breeding of P. porphyrae-infection tolerant macroalgae.

The Gram-stain-negative, rod-shaped, aerobic strain, designated YC1039 T , was isolated from a seamount northern Mariana Trench in the tropical western Pacific. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain YC1039 T was related to the genus Mesoflavibacter and had highest 16S rRNA gene sequence similarities to Mesoflavibacter sabulilitoris GJMS-9 T (98.3%) and Mesoflavibacter zeaxanthinifaciens TD-ZX30 T (98.2%). The predominant cellular fatty acids were iso-C 15:1 G and iso-C 15:0 . The polar lipid profile contained phosphatidylethanolamine, two unidentified phospholipids, and 13 unidentified lipids. The respiratory quinone was MK-6. The genomic DNA G+C content of strain YC1039 T was 29.8 mol%. On the basis of the evidence presented in this study, strain YC1039 T represents a novel species of the genus Mesoflavibacter, for which we propose the name Mesoflavibacter profundi sp. nov. (type strain YC1039 T  = KACC 19026 T  = CGMCC 1.16329 T ).

An aerobic, Gram-stain negative, rod-shaped, non-motile bacterium, designated as strain HQA918 T , was isolated from an ascidian, Botryllus schlosseri, which was collected from the coast of Weihai in the north of the Yellow Sea, in China. The strain grew optimally at 28-30 °C, at pH values 7.0-8.0, and in the presence of 1.0-3.0% (w/v) sodium chloride (NaCl). A phylogenetic analysis based on 16S rRNA gene sequences showed that strain HQA918 T can be affiliated with the family Flavobacteriaceae in the phylum Bacteroidetes, with 92.7% similarity to its close relatives. The major fatty acids identified were iso-C 15:0 , iso-C 15:0 3-OH, and summed feature 3 (iso-C 15:0 2-OH and/or C 16:1 ω7c). The major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, and five unidentified polar lipids. The G+C content of the genomic DNA was 44.1 mol%. On the basis of the phylogenetic, genotypic, phenotypic, and chemotaxonomic data, this organism should be classified as a representative of a novel genus, for which the name Ascidiaceibacter gen. nov. is proposed. The type species is Ascidiaceibacter salegens sp. nov. (type strain HQA918 T  = KCTC 52719 T  = MCCC 1K03259 T ).

A Gram-negative, non-motile, aerobic bacterium, designated strain IP7 T , was isolated from seawater at the shore of the Incheon Eulwang-ri beach, South Korea. Cells of strain IP7 T are straight or slightly rod-shaped and colonies are round, convex and orange-yellow. Strain IP7 T is flexirubin-negative, mild halophile, catalase-and oxidase-positive, and produces a yellow-orange carotenoid pigment. Growth is optimal at 30°C, pH 7-9, and 2.0-4.0% NaCl (w/v). On the basis of 16S rRNA gene sequence similarity, strain IP7 T is affiliated with genus Aestuariibaculum in the family Flavobacteriaceae, the closest relative being Aestuariibaculum suncheonense SC17 T (98.3% sequence similarity). The DNA G + C content of the novel strain is 37.4 mol%. The only quinone is MK-6 menaquinone. Iso-branched C 15:0 , iso-branched C 15:1 G, and iso-branched C 17:0 3-OH are major fatty acids. The major polar lipids are phosphatidylethanolamine, an unidentified aminoglycolipid and two unidentified glycolipids. The DNA-DNA hybridization value of strain IP7 T with Aestuariibaculum suncheonense SC17 T is 28.87%. Based on the collective DNA-DNA hybridization, biochemical, phylogenetic and physiological data, we report a novel species of the genus Aestuariibaculum for which the name Aestuariibaculum marinum sp. nov. is proposed. The type strain is IP7 T (= KCTC 52521 T = JCM 31725 T ).

Background: Myroides spp. are common environmental organisms and they can be isolated predominantly in water, soil, food and in sewage treatment plants. In the last two decades, an increasing number of infections such as urinary tract infections and skin and soft tissue infections, caused by these microorganisms has been reported. Selection of appropriate antibiotic therapy to treat the infections caused by Myroides spp . is difficult due to the production of a biofilm and the organism's intrinsic resistance to many antibiotic classes., Case Presentation: We report the case of a 69-year-old immunocompromised patient who presented with repeated episodes of macroscopic haematuria, from Northern Italy.A midstream urine sample cultured a Gram negative rod in significant amounts (> 10 5 colony-forming units (cfu)/mL), which was identified as Myroides odoratimimus. The patient was successfully treated with trimethoprim/sulfamethoxazole after antibiotic susceptibility testing confirmed its activity., Conclusion: This case underlines the emergence of multidrug resistant Myroides spp. which are ubiquitous in the environment and it demands that clinicians should be more mindful about the role played by atypical pathogens, which may harbour or express multidrug resistant characteristics, in immunocompromised patients or where there is a failure of empiric antimicrobial therapy., Competing Interests: Not necessary for case reports.Written informed consent was provided by the patient for the publication of this case report.The authors declare that they have no competing interests.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Sponges interact with diverse and rich communities of bacteria that are phylogenetically often distinct from their free-living counterparts. Recent genomics and metagenomic studies have indicated that bacterial sponge symbionts also have distinct functional features from free-living bacteria; however, it is unclear, if such genome-derived functional signatures are common and present in different symbiont taxa. We therefore compared here a large set of genomes from cultured (Pseudovibrio, Ruegeria and Aquimarina) and yet-uncultivated (Synechococcus) bacteria found in either sponge-associated or free-living sources. Our analysis revealed only very few genera-specific functions that could be correlated with a sponge-associated lifestyle. Using different sets of sponge-associated and free-living bacteria for each genus, we could however show that the functions identified as 'sponge-associated' are dependent on the reference comparison being made. Using simulation approaches, we show how this influences the robustness of identifying functional signatures and how evolutionary divergence and genomic adaptation can be distinguished. Our results highlight the future need for robust comparative analyses to define genomic signatures of symbiotic lifestyles, whether it is for symbionts of sponges or other host organisms., (© 2018 Society for Applied Microbiology and John Wiley & Sons Ltd.)

We report the isolation and characterization of two Elizabethkingia anophelis strains (OSUVM-1 and OSUVM-2) isolated from sources associated with horses in Oklahoma. Both strains appeared susceptible to fluoroquinolones and demonstrated high MICs to all cell wall active antimicrobials including vancomycin, along with aminoglycosides, fusidic acid, chloramphenicol, and tetracycline. Typical of the Elizabethkingia, both draft genomes contained multiple copies of β-lactamase genes as well as genes predicted to function in antimicrobial efflux. Phylogenetic analysis of the draft genomes revealed that OSUVM-1 and OSUVM-2 differ by only 6 SNPs and are in a clade with 3 strains of Elizabethkingia anophelis that were responsible for human infections. These findings therefore raise the possibility that Elizabethkingia might have the potential to move between humans and animals in a manner similar to known zoonotic pathogens., Competing Interests: The authors have declared that no competing interests exist.

Phage-host interactions are critical to ecology, evolution, and biotechnology. Central to those is infection efficiency, which remains poorly understood, particularly in nature. Here we apply genome-wide transcriptomics and proteomics to investigate infection efficiency in nature's own experiment: two nearly identical (genetically and physiologically) Bacteroidetes bacterial strains (host18 and host38) that are genetically intractable, but environmentally important, where phage infection efficiency varies. On host18, specialist phage phi18:3 infects efficiently, whereas generalist phi38:1 infects inefficiently. On host38, only phi38:1 infects, and efficiently. Overall, phi18:3 globally repressed host18's transcriptome and proteome, expressed genes that likely evaded host restriction/modification (R/M) defenses and controlled its metabolism, and synchronized phage transcription with translation. In contrast, phi38:1 failed to repress host18's transcriptome and proteome, did not evade host R/M defenses or express genes for metabolism control, did not synchronize transcripts with proteins and its protein abundances were likely targeted by host proteases. However, on host38, phi38:1 globally repressed host transcriptome and proteome, synchronized phage transcription with translation, and infected host38 efficiently. Together these findings reveal multiple infection inefficiencies. While this contrasts the single mechanisms often revealed in laboratory mutant studies, it likely better reflects the phage-host interaction dynamics that occur in nature.

Flavobacterial diseases are significant impediments to hatchery-based fishery conservation and aquaculture productivity worldwide. Recent studies revealed a multitude of novel flavobacteria within the reproductive fluids and unfertilized eggs of feral Chinook salmon Oncorhynchus tshawytscha broodstock, some of which were associated with systemic disease. Herein, embryonated eggs/fry from these broodstock were assayed for flavobacteria while in incubator stacks in three hatcheries over 2 years, as was the water entering hatchery incubators. Overall, >65% of sampled eggs and 38% of fry were colonized by flavobacteria. One hundred and ninety-one egg and fry-associated flavobacterial isolates were characterized phenotypically and via 16S rRNA gene sequencing and phylogenetic analyses, revealing that the majority fell into 22 clades (i.e., 15 Flavobacterium spp. groups and seven Chryseobacterium spp. groups) that varied in presence by facility. Although some matched previously described fish-pathogenic species, the majority were distinct from all described flavobacteria and likely represent novel species. Of concern, iodophor disinfection at the commonly utilized dose/duration for egg-surface disinfection did not eliminate flavobacteria. Results also implicated maternal routes of infection and source water for some flavobacteria. In total, study findings underscore the complexity of flavobacterial ecology within hatchery environments and highlight the need for improved hatchery biosecurity practices., (© 2018 John Wiley & Sons Ltd.)

Iridescence is an original type of colouration that is relatively widespread in nature but has been either incompletely described or entirely neglected in prokaryotes. Recently, we reported a brilliant 'pointillistic' iridescence in agar-grown colony biofilms of Cellulophaga lytica and some other marine Flavobacteria that exhibit gliding motility. Bacterial iridescence is created by a unique self-organization of sub-communities of cells, but the mechanisms underlying such living photonic crystals are unknown. In this study, we used Petri dish assays to screen a large panel of potential activators or inhibitors of C. lytica's iridescence. Derivatives potentially interfering with quorum-sensing and other communication or biofilm formation processes were tested, as well as metabolic poisons or algal exoproducts. We identified an indole derivative, 5-hydroxyindole (5HI, 250 µM) which inhibited both gliding and iridescence at the colonial level. 5HI did not affect growth or cell respiration. At the microscopic level, phase-contrast imaging confirmed that 5HI inhibits the gliding motility of cells. Moreover, the lack of iridescence correlated with a perturbation of self-organization of the cell sub-communities in both the WT and a gliding-negative mutant. This effect was proved using recent advances in machine learning (deep neuronal networks). In addition to its effect on colony biofilms, 5HI was found to stimulate biofilm formation in microplates. Our data are compatible with possible roles of 5HI or marine analogues in the eco-biology of iridescent bacteria.

We report a case of recurrent post-traumatic ulcer infection due to Myroides odoratimimus in an immunocompromised male. We have also reviewed the medical literature on isolated M. odoratimimus infections. The strain, isolated from ulcer discharge, was multidrug-resistant and treatment with meropenem, based on susceptibility testing, led to resolution of infection. The strain was also able to form a relevant amount of biofilm over time, thus suggesting a possible role of sessile communities in the chronicization of infection. To our knowledge, this is the first description of recurrent ulcer infection caused by a biofilm-producer M. odoratimimus strain. This case reminds us of the need to consider uncommon pathogens as etiology of skin and soft tissue infections, especially in immunocompromised patients. Further, since the treatment of infections due to M. odoratimimus is often difficult both due to multidrug resistance and scarce clinical experience, antibiotic therapy should be adapted to in vitro susceptibility testing.

Freezing temperatures are a major challenge for life at the poles. Decreased membrane fluidity, uninvited secondary structure formation in nucleic acids, and protein cold-denaturation all occur at cold temperatures. Organisms adapted to polar regions possess distinct mechanisms that enable them to survive in extremely cold environments. Among the cold-induced proteins, cold shock protein (Csp) family proteins are the most prominent. A gene coding for a Csp-family protein, cspB, was cloned from an arctic bacterium, Polaribacter irgensii KOPRI 22228, and overexpression of cspB greatly increased the freeze-survival rates of Escherichia coli hosts, to a greater level than any previously reported Csp. It also suppressed the cold-sensitivity of an E. coli csp-quadruple deletion strain, BX04. Sequence analysis showed that this protein consists of a unique domain at its N-terminal end and a well conserved cold shock domain at its C-terminal end. The most common mechanism of Csp function in cold adaption is melting of the secondary structures in RNA and DNA molecules, thus facilitating transcription and translation at low temperatures. P. irgensii CspB bound to oligo(dT)-cellulose resins, suggesting single-stranded nucleic acid-binding activity. The unprecedented level of freeze-tolerance conferred by P. irgensii CspB suggests a crucial role for this protein in survival in polar environments., (Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.)

Heterotrophic microbial communities process much of the carbon fixed by phytoplankton in the ocean, thus having a critical role in the global carbon cycle. A major fraction of the phytoplankton-derived substrates are high-molecular-weight (HMW) polysaccharides. For bacterial uptake, these substrates must initially be hydrolysed to smaller sizes by extracellular enzymes. We investigated polysaccharide hydrolysis by microbial communities during a transect of the Atlantic Ocean, and serendipitously discovered-using super-resolution structured illumination microscopy-that up to 26% of total cells showed uptake of fluorescently labelled polysaccharides (FLA-PS). Fluorescence in situ hybridisation identified these organisms as members of the bacterial phyla Bacteroidetes and Planctomycetes and the gammaproteobacterial genus Catenovulum. Simultaneous membrane staining with nile red indicated that the FLA-PS labelling occurred in the cell but not in the cytoplasm. The dynamics of FLA-PS staining was further investigated in pure culture experiments using Gramella forsetii, a marine member of Bacteroidetes. The staining patterns observed in environmental samples and pure culture tests are consistent with a 'selfish' uptake mechanisms of larger oligosaccharides (>600 Da), as demonstrated for gut Bacteroidetes. Ecologically, this alternative polysaccharide uptake mechanism secures substantial quantities of substrate in the periplasmic space, where further processing can occur without diffusive loss. Such a mechanism challenges the paradigm that hydrolysis of HMW substrates inevitably yields low-molecular-weight fragments that are available to the surrounding community and demonstrates the importance of an alternative mechanism of polysaccharide uptake in marine bacteria.

A series of eight novel siloxane-polyurethane fouling-release (FR) coatings were assessed for their FR performance in both the laboratory and in the field. Laboratory analysis included adhesion assessments of bacteria, microalgae, macroalgal spores, adult barnacles and pseudobarnacles using high-throughput screening techniques, while field evaluations were conducted in accordance with standardized testing methods at three different ocean testing sites over the course of six-months exposure. The data collected were subjected to statistical analysis in order to identify potential correlations. In general, there was good agreement between the laboratory screening assays and the field assessments, with both regimes clearly distinguishing the siloxane-polyurethane compositions comprising monofunctional poly(dimethyl siloxane) (PDMS) (m-PDMS) as possessing superior, broad-spectrum FR properties compared to those prepared with difunctional PDMS (d-PDMS). Of the seven laboratory screening techniques, the Cellulophaga lytica biofilm retraction and reattached barnacle (Amphibalanus amphitrite) adhesion assays were shown to be the most predictive of broad-spectrum field performance.

Iridescent color appearances are widespread in nature. They arise from the interaction of light with micron- and submicron-sized physical structures spatially arranged with periodic geometry and are usually associated with bright angle-dependent hues. Iridescence has been reported for many animals and marine organisms. However, iridescence has not been well studied in bacteria. Recently, we reported a brilliant "pointillistic" iridescence in colony biofilms of marine Flavobacteria that exhibit gliding motility. The mechanism of their iridescence is unknown. Here, using a multi-disciplinary approach, we show that the cause of iridescence is a unique periodicity of the cell population in the colony biofilm. Cells are arranged together to form hexagonal photonic crystals. Our model highlights a novel pattern of self-organization in a bacterial biofilm. "Pointillistic" bacterial iridescence can be considered a new light-dependent phenomenon for the field of microbiology.

An aerobic, Gram-stain negative, non-spore-forming and psychrotolerant bacterium, designated strain XJ109(T), was isolated from a sewage water sample collected from Xinjiang Uigur Autonomous Region, China. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain XJ109(T) represents a novel member of the family Flavobacteriaceae. The strain showed 95.5 % similarity with the 16S rRNA gene sequence of Empedobacter brevis LMG 4011(T), 95.4% with Chishuiella changwenlii BY4(T), 95.3% with Empedobacter falsenii NF 993(T) and 92.3% with Weeksella virosa DSM 16922(T). Strain XJ109(T) showed the common phenotypic and chemotaxonomic characteristics of the family Flavobacteriaceae, containing menaquinone-6 (MK-6) as the predominant respiratory quinone and iso-C17:0 3OH and iso-C15:0 as the major fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, one unidentified phospholipid and two unidentified lipids. The genomic DNA G+C content was 38.0 mol%. Strain XJ109(T) was positive for catalase and oxidase activities, and it was observed to grow at 4-30 °C (optimal 16-20 °C), pH 6.5-10.0 (optimal 7.0-7.5) and in media containing 0-2.0% (w/v) NaCl (optimal 0.5 %). On the basis of the polyphasic evidence presented, strain XJ109(T) is considered to represent a novel genus and species of the family Flavobacteriaceae, for which the name Algoriella xinjiangensis gen. nov., sp. nov. is proposed. The type strain is XJ109(T) (=CGMCC 1.10229(T)=JCM 16590(T)).

A novel pale-yellow coloured bacterial strain, designated AM327(T), was isolated by using an in situ cultivation technique from seawater from the coastal zone around a shipyard located in Otsuchi Bay, Japan. The strain was found to be facultatively anaerobic, Gram-stain negative, chemoheterotrophic, non-motile and rod-shaped. Preliminary analysis based on the 16S rRNA gene sequence revealed that the novel isolate is affiliated with the family Flavobacteriaceae of the phylum Bacteroidetes and that it shows high sequence similarity (94.7 %) to Frondibacter aureus A5Q-67(T). The strain can be differentiated phenotypically from recognised members of the family Flavobacteriaceae. The DNA G+C content of strain AM327(T) was determined to be 36.2 mol%; MK-6 was identified as the major menaquinone; iso-C15:0 and iso-C17:0 3-OH were identified as the major (>10 %) cellular fatty acids. The polar lipid profile was found to consist of phosphatidylethanolamine, an unidentified aminophospholipid, an unidentified glycolipid and two unidentified lipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, strain AM327(T) is considered to represent a novel genus for which the name Neptunitalea chrysea gen. nov., sp. nov. is proposed. The type strain of N. chrysea is AM327(T) (=KCTC 32989(T) = NBRC 110019(T)).

A polyphasic taxonomic investigation was performed on a bacterial strain, 38-Ka-2(T), which was isolated from the green alga Ulva pertusa Kjellman (Chlorophyta) in Hokkaido, Japan. The bacterial cells were observed to be golden-yellow coloured, Gram-negative, strictly aerobic, non-spore-forming, non-motile and rod-shaped. Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain is a member of the family Flavobacteriaceae within the phylum Bacteroidetes and that it shows high sequence similarity (94.8 %) to Aquimarina addita JC2680(T). The genomic DNA G+C content of strain 38-Ka-2(T) was determined to be 36 mol%; MK-6 was identified as the major menaquinone; and the presence of iso-C15:0, C18:0 and iso-C17:0 3-OH as the major (>10 %) cellular fatty acids. The polar lipid profile was found to consist of phosphatidylethanolamine, an unidentified glycolipid and two unidentified lipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, strain 38-Ka-2(T) is considered to represent a novel genus for which the name Algitalea ulvae gen. nov., sp. nov. is proposed. The type strain of A. ulvae is 38-Ka-2(T) (=KCTC 32994(T) = NBRC 110017(T)).

A novel Gram-stain negative, spherical, non-motile, strictly aerobic, heterotrophic, yellow pigmented bacterium, designated strain 04OKA003-7(T) was isolated from the hard coral Galaxea fascicularis L. collected at Akajima, Okinawa, Japan. Phylogenetic analysis based on the 16S rRNA gene sequence revealed the novel isolate is affiliated with the family Flavobacteriaceae of the phylum Bacteroidetes and that it showed highest sequence similarity (92.9 %) to Vitellibacter aestuarii JC2436(T) and Aureitalea marina S1-66(T). The strain could be differentiated phenotypically from recognized members of the family Flavobacteriaceae. The major fatty acids of strain 04OKA003-7(T) were identified as iso-C15:0 and iso-C17:0 3-OH as defined by the MIDI system. The DNA G+C content was determined to be 41 mol%, the major respiratory quinone was identified as menaquinone 6 (MK-6) and a polar lipid profile was present consisting of phosphatidylethanolamine, two unidentified aminolipids and an unidentified lipid. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus for which the name Aureisphaera galaxeae gen. nov., sp. nov. is proposed. The type strain of A. galaxeae is 04OKA003-7(T) (=KCTC 32993(T) = NBRC 110018(T)).

A Gram-negative, strictly aerobic, beige-pigmented, non-motile, rod-shaped bacterial strain designated N5DB13-4(T) was isolated from the red alga Gracilaria vermiculophylla (Rhodophyta) collected at Sodegaura Beach, Chiba, Japan. Phylogenetic analyses based on the 16S rRNA gene sequence revealed that the novel isolate is affiliated with the family Flavobacteriaceae within the phylum Bacteroidetes and that it showed highest sequence similarity (97.3 %) to Wenyingzhuangia heitensis H-MN17(T). The hybridization values for DNA-DNA relatedness between the strains N5DB13-4(T) and W. heitensis H-MN17(T) were 34.1 ± 3.5 %, which is below the threshold accepted for the phylogenetic definition of a novel prokaryotic species. The DNA G+C content of strain N5DB13-4(T) was determined to be 31.8 mol%; MK-6 was identified as the major menaquinone; and the presence of iso-C15:0, iso-C15:0 3-OH and iso-C17:0 3-OH as the major (>10 %) cellular fatty acids. A complex polar lipid profile was present consisting of phosphatidylethanolamine, two unidentified glycolipids and four unidentified lipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel species of the genus Wenyingzhuangia for which the name Wenyingzhuangia gracilariae sp. nov. is proposed. The type strain of W. gracilariae sp. nov. is N5DB13-4(T) (=KCTC 42246 (T)=NBRC 110602(T)).

Elizabethkingia anophelis is an emerging pathogen that can cause life-threatening infections in neonates, severely immunocompromised and postoperative patients. The lack of genomic information on E. anophelis hinders our understanding of its mechanisms of pathogenesis. Here, we report the first complete genome sequence of E. anophelis NUHP1 and assess its response to oxidative stress. Elizabethkingia anophelis NUHP1 has a circular genome of 4,369,828 base pairs and 4,141 predicted coding sequences. Sequence analysis indicates that E. anophelis has well-developed systems for scavenging iron and stress response. Many putative virulence factors and antibiotic resistance genes were identified, underscoring potential host-pathogen interactions and antibiotic resistance. RNA-sequencing-based transcriptome profiling indicates that expressions of genes involved in synthesis of an yersiniabactin-like iron siderophore and heme utilization are highly induced as a protective mechanism toward oxidative stress caused by hydrogen peroxide treatment. Chrome azurol sulfonate assay verified that siderophore production of E. anophelis is increased in the presence of oxidative stress. We further showed that hemoglobin facilitates the growth, hydrogen peroxide tolerance, cell attachment, and biofilm formation of E. anophelis NUHP1. Our study suggests that siderophore production and heme uptake pathways might play essential roles in stress response and virulence of the emerging pathogen E. anophelis., (© The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)

The gene encoding proteorhodopsin AEX55013 from Dokdonia sp. PRO95 was cloned and expressed in Escherichia coli cells. Illumination of the proteorhodopsin-producing E. coli cells in Na+-containing media resulted in alkalinization of the media. This response was accelerated by uncoupler CCCP and inhibited by penetrating anion SCN(-). Illumination of the cells in a sodium-free medium (made by substituting Na+ with K+) resulted in SCN(-)-stimulated and CCCP-sensitive acidification of the medium. Illumination of the proteorhodopsin-containing E. coli cells caused CCCP-resistant transmembrane sodium export from these cells. We conclude that the proteorhodopsin from the marine flavobacterium Dokdonia sp. PRO95 is a primary light-driven Na+-pump. A high level of the heterologous production in E. coli cells as well as stability and purity of the isolated protein makes this proteorhodopsin an attractive model for studying the mechanism of active sodium transmembrane translocation.

A Gram-stain negative, non-spore-forming, non-motile, strictly aerobic bacterial strain, designated CAU 1296(T), was isolated from an aquafarm waste water sludge and its taxonomic position was investigated using a polyphasic approach. Cells of strain CAU 1296(T) grew optimally at 30 °C, at pH 7.5 and in the presence of 4 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CAU 1296(T) formed a distinct lineage within the genus Eudoraea and exhibited similarity to Eudoraea adriatica AS06/20a(T) (95.4 % similarity). The major cellular fatty acids of the isolate were iso-C15:0, iso-C15:1 G, and summed feature 3 (C16:1 ω6c and C16:1 ω7c). The polar lipid pattern of strain CAU 1296(T) consisted of phosphatidylethanolamine, and unidentified lipids including a phosphoglycolipid, phospholipid, glycolipid, aminophospholipid, two aminolipids, and six further unidentified lipids. The strain contained menaquinone-6 (MK-6) as the major isoprenoid quinone. The G+C content of the genomic DNA was 38.7 mol%. On the basis of phenotypic, chemotaxonomic, and phylogenetic data, strain CAU 1296(T) should be classified as a novel species in the genus Eudoraea, for which the name Eudoraea chungangensis sp. nov. is proposed. The type strain is CAU 1296(T) (=KCTC 42048(T), =CCUG 66239(T), =CECT 8744(T)).

A group of five Gram-negative strains isolated from clams (Venerupis decussata and Venerupis philippinarum) in Galicia (NW Spain) were analyzed using a polyphasic taxonomic approach. The strains were non-motile, strictly aerobic rods, and formed yellow-pigmented colonies. Based on 16S rRNA gene sequence similarity, the clam isolates belonged to the Lacinutrix genus, within the Flavobacteriaceae family, and showed the highest sequence similarities with Lacinutrix mariniflava (97.0%) and Lacinutrix algicola (96.9%). The DNA G+C content of the designated type strain Cmf 20.8(T) was 34.1%, which was within the range of the other species in the genus (29.0-37.0%). The main cellular fatty acids of the type strain Cmf 20.8(T) were iso-C15:0 3-OH, iso-C15:1 G, iso-C15:0 and iso-C17:0 3-OH. The DNA-DNA analysis value of strain Cmf 20.8(T) with L. mariniflava AKS292(T) was 51% and with L. algicola AKS293(T) it was 56%. Phenotypic data showed that the isolates could be differentiated easily from the other species of the genus. On the basis of these results, the strains represent a novel species of the genus Lacinutrix, for which the name Lacinutrix venerupis sp. nov. is proposed, with Cmf 20.8(T) (=CECT 8573(T)=DSM 28755(T)) as the designated type strain., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

A Gram-negative, strictly aerobic, beige-pigmented, non-motile, rod-shaped strain designated H-MN17(T) was isolated from seawater in Japan. Phylogenetic analyses based on the 16S rRNA gene sequence revealed that the novel isolate was affiliated with the family Flavobacteriaceae within the phylum Bacteroidetes and that it showed highest sequence similarity (97.5 %) to Wenyingzhuangia marina D1(T). The hybridization values for DNA-DNA relatedness between the strains of H-MN17(T) and W. marina D1(T) were lower than 70 %, which is accepted as the phylogenetic definition of a novel species. The DNA G+C content of strain H-MN17(T) was 31.8 mol%; MK-6 was the major menaquinone; and anteiso-C15:0, anteiso-C17:0 and anteiso-C19:0 were identified as the major (>10 %) cellular fatty acids. A complex polar lipid profile was present consisting of phosphatidylethanolamine, three unidentified lipids, three unidentified glycolipids and three unidentified aminolipids. From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel species of the genus Wenyingzhuangia for which the name Wenyingzhuangia heitensis sp. nov. is proposed. The type strain of W. heitensis sp. nov. is H-MN17(T) (=KCTC 42245(T) = NBRC 110601(T)).

A Gram-negative, yellow-pigmented, rod-shaped bacteria, designated M09-0166(T)and M09-1053 were isolated from human urine samples. 16S rRNA gene sequence analysis revealed that the isolates belong to the Myroides cluster and were closely related to Myroides phaeus DSM 23313(T) (96.3 %), Myroides odoratimimus KCTC 23053(T) (96.1 %), Myroides profundi KCTC 23066(T) (96.0 %), Myroides odoratus KCTC 23054(T) (95.4 %) and Myroides pelagicus KCTC 12661(T) (95.2 %). The major mena quinone was identified as MK-6. The major polar lipids were identified as phosphatidylethanolamine, amino lipids, and several unknown lipids, and the major fatty acids as iso-C15:0 and iso-C17:0 3-OH. Phenotypic and chemotaxonomic data supported the affiliation of the isolates with the genus Myroides and clearly indicated that two isolates represent novel species, for which the name Myroides injenensis sp. nov. (type strain, M09-0166(T) = KCTC 23367(T) = JCM 17451(T)) is proposed.

A Gram-stain negative, non-flagellated, non-gliding, aerobic and rod-shaped bacterium, designated GYSW-15(T), was isolated from a seawater of Geoje island on the South Sea, South Korea, and subjected to a polyphasic taxonomic approach. Strain GYSW-15(T) was found to grow optimally at 30 °C, at pH 7.0-8.0 and in the presence of approximately 2.0 % (w/v) NaCl. Neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain GYSW-15(T) belongs to the genus Polaribacter, clustering coherently with the type strain of Polaribacter porphyrae showing sequence similarity value of 97.0 %. Strain GYSW-15(T) exhibited 16S rRNA gene sequence similarity values of 94.3-96.4 % to the type strains of the other Polaribacter species. Strain GYSW-15(T) was found to contain MK-6 as the predominant menaquinone and iso-C15:0, iso-C15:1 G, iso-C16:0 3-OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) as the major fatty acids. The polar lipid profile of strain GYSW-15(T) containing phosphatidylethanolamine and an unidentified lipid as major components was similar to that of the type strain of P. porphyrae. The DNA G + C content of strain GYSW-15(T) was determined to be 31.2 mol% and its mean DNA-DNA relatedness with P. porphyrae LMG 26671(T) was 17 %. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain GYSW-15(T) is separated from recognized Polaribacter species. On the basis of the data presented, strain GYSW-15(T) is considered to represent a novel species of the genus Polaribacter, for which the name Polaribacter marinivivus sp. nov. is proposed. The type strain is GYSW-15(T) ( = KCTC 42156(T) = CECT 8655(T)).

A Gram-strain negative, rod-shaped and gliding bacterial strain, designated HD-44(T), was isolated from a tidal flat sediment in the Korean peninsula. Strain HD-44(T) was found to grow optimally at pH 7.0-8.0, at 25° C and in the presence of 2-3% (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain HD-44(T) falls within the clade comprising the Maribacter species, clustering with the type strains of Maribacter aquivivus, Maribacter ulvicola, Maribacter stanieri, Maribacter dokdonensis, Maribacter orientalis, Maribacter forsetii, Maribacter arcticus and Maribacter sedimenticola, with which it exhibits 97.1-98.3% sequence similarity values. Sequence similarities to the type strains of the other recognized Maribacter species are 95.6-96.8%. Strain HD-44(T) was found to contain MK-6 as the predominant menaquinone and iso-C(17:0)3-OH, iso-C(15:1)G, iso-C(15:0) and summed feature 3 (C(16:1)ω6c and/or C(16:1)ω7c) as the major fatty acids. The major polar lipids were identified as phosphatidylethanolamine and two unidentified lipids. The DNA G+C content of strain HD-44(T) was determined to be 37.6 mol% and its mean DNA-DNA relatedness values with M. aquivivus KCTC 12968(T), M. ulvicola KCTC 12969(T), M. stanieri KCTC 22023(T), M. dokdonensis DSW-8(T), M. orientalis KCTC 12967(T), M. forsetii KT02ds18-6(T), M. arcticus KCTC 22053(T) and M. sedimenticola KCTC 12966(T) were 27.7-8.0%. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain HD-44(T) is distinguishable from recognized Maribacter species. On the basis of the data presented, strain HD-44(T) is proposed to represent a novel species of the genus Maribacter, for which the name Maribacter caenipelagi sp. nov. is proposed. The type strain is HD-44(T) (= KCTC 32549(T) = CECT 8455(T)).

A novel Gram-negative, non-flagellated, non-gliding, rod-shaped bacterial strain, designated PB-M7(T), was isolated from the intestine of a sea cucumber collected from Pohang, South Korea. Growth was observed at 4-30 °C (optimum, 25 °C), pH 6.0-9.0 (optimum, pH 7.0-8.0), and with 2.0-6.0% (w/v) NaCl (optimum, 2.0%). In a phylogenetic analysis based on 16S rRNA gene sequences, strain PB-M7(T) was found to belong to the genus Bizionia and to be most closely related to Bizionia echini KMM 6177(T) (99.0% 16S rRNA gene sequence similarity), Bizionia hallyeonensis T-y7(T) (97.9%), Bizionia algoritergicola APA-1(T) (97.5%), Bizionia argentinensis JUB59(T) (97.5%) and Bizionia myxarmorum ADA-4(T) (97.1%). The predominant fatty acids of strain PB-M7(T) were identified as iso-C(15:0) (22.2%), iso-C(15:1) G (10.8%), iso-C(17:0) 3-OH (16.7%) and summed feature 3 (C(16:1) ω7c and/or C(16:1) ω6c; 11.2%). The major respiratory quinone was identified as menaquinone-6 (MK-6). The polar lipid profile of strain PB-M7(T) was found to contain phosphatidylethanolamine, an unidentified phospholipid, three unidentified aminolipids and three unidentified lipids. The DNA G + C content of strain PB-M7(T) was determined to be 33.4 mol% and the mean DNA-DNA relatedness values with the type strains of B. echini, B. hallyeonensis, B. algoritergicola, B. argentinensis, and B. myxarmorum were 52.9, 48.5, 46.5, 37.1 and 26.6%, respectively. Based on the data presented, strain PB-M7(T) represents a novel species of the genus Bizionia, for which the name Bizionia psychrotolerans sp. nov. is proposed. The type strain of B. psychrotolerans is PB-M7(T) (= KCCM 43042 (T) = JCM 19924 (T)).

A Gram-stain negative, non-flagellated, non-gliding and rod-shaped bacterium, strain JHH-2(T), was isolated from seawater collected in Jeju Island, Korea. The novel isolate was found to grow at 25-30 °C, at pH 6.5-7.0 and in the presence of 1-2% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain JHH-2(T) is closely related to Siansivirga zeaxanthinifaciens JCM 17682(T), with 16S rRNA gene sequence similarity of 96.6%. The predominant respiratory quinone was identified as menaquinone-6 and the major cellular fatty acids were detected as iso-C(15:0), C(16:0) and iso-C(17:0) 3-OH. Polar lipid profiling revealed the presence of phosphatidylethanolamine, an unidentified glycolipid, four unidentified aminolipids and two unidentified lipids. The DNA G+C content of the chromosomal DNA of the type strain is 35.6 mol%. On the basis of several distinct phenotypic characteristics and phylogenetic analysis, a new species of the genus Siansivirga, Siansivirga jejuensis [corrected] JHH-2(T) sp. nov. is proposed. The type strain is JHH-2(T) (= KCCM 90230(T) = JCM 19228(T)). [corrected].

A facultatively anaerobic, Gram-stain negative, rod-shaped and yellow pigmented bacterium, designated strain IDSW-73(T), was isolated from a seawater sample and subjected to a polyphasic taxonomic study. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the novel strain formed a distinct phyletic line in the family Flavobacteriaceae and is most closely related to the members of the genus Leeuwenhoekiella, with 16S rRNA gene sequence similarity of 91.4-92.6 %. Strain IDSW-73(T) was found to be able to grow with 0-12 % NaCl and at 4-33 °C; and was able to hydrolyse gelatin, starch and Tweens 20, 40 and 80. The DNA G+C content was determined to be 42.2 mol%. The predominant cellular fatty acids were identified as branched-chain saturated and unsaturated and straight-chain unsaturated fatty acids such as iso-C15:0, iso-C15:1, iso-C17:1 ω9c, C15:1 ω6c, iso-C15:0 3-OH, iso-C17:0 3-OH and summed feature 3 (as defined by MIDI), comprising iso-C15:0 2-OH and/or C16:1 ω7c. The polar lipids found were phosphatidylethanolamine, two unknown aminolipids and one unknown lipid. The major respiratory quinone was identified as MK-6. The significant molecular distinctiveness between the novel isolate and its nearest neighbours were strongly supported by notable differences in physiological and biochemical tests. Therefore, strain IDSW-73(T) is considered to represent a novel genus and species within the family Flavobacteriaceae, for which the name Flavimarina pacifica gen. nov., sp. nov. is proposed. The type strain is IDSW-73(T) (=KCTC 32466(T) = KMM 6759(T)). Emended descriptions of the recognized species of the genus Leeuwenhoekiella are also proposed.

A Gram-negative, strictly aerobic, non-motile, rod-shaped and psychrophilic bacterial strain, PAMC 27137(T), was isolated from the marine sediment of the Ross Sea, Antarctica. Strain PAMC 27137(T) was observed to grow at 4-10 °C, at pH 6.5-7.5 and in the presence of 2.5-4.0 % (w/v) sea salts. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain PAMC 27137(T) belongs to the genus Lacinutrix showing the high similarities with Lacinutrix mariniflava JCM 13824(T) (97.6 %) and Lacinutrix algicola JCM 13825(T) (97.1 %). Genomic relatedness analyses based on the average nucleotide identity and the genome-to-genome distance showed that strain PAMC 27137(T) is clearly distinguished from the most closely related Lacinutrix species. The major fatty acids (>5 %) were identified as iso-C15:1 G (19.9 %), iso-C15:0 (19.3 %), iso-C17:0 3-OH (11.3 %), summed feature 9 (C16:0 10-methyl and/or iso-C17:1 ω9c as defined by MIDI, 9.1 %), iso-C15:0 3-OH (7.5 %), and anteiso-C15:1 A (5.8 %). The polar lipids were found to consist of phosphatidylethanolamine, an unidentified aminolipid, an unidentified aminophospholipid, and five unidentified phospholipids. The major respiratory quinone was identified as MK-6. The genomic DNA G+C content was determined to be 32.1 mol%. Based on the data from this polyphasic taxonomic study, strain PAMC 27137(T) is considered to represent a novel species of the genus Lacinutrix, for which the name Lacinutrix jangbogonensis sp. nov. is proposed. The type strain is PAMC 27137(T) (=KCTC 32573(T)=JCM 19883(T)).

A Gram-negative, aerobic, non-flagellated and rod-shaped bacterial strain able to move by gliding, designated TYO-10(T), was isolated from an oyster collected at Tongyoung on the South Sea, South Korea. Strain TYO-10(T) was found to grow optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain TYO-10(T) joined the cluster comprising the type strains of Mariniflexile species. Strain TYO-10(T) exhibited 16S rRNA gene sequence similarity values of 95.4-95.7 % to the type strains of Mariniflexile species and of less than 95.4 % to the type strains of other recognized species. Strain TYO-10(T) was found to contain MK-6 as the predominant menaquinone and iso-C15:0, iso-C15:1 G, anteiso-C15:0, iso-C17:0 3-OH and iso-C15:0 3-OH as the major fatty acids. The major polar lipids of strain TYO-10(T) were identified as phosphatidylethanolamine and an unidentified lipid, which is similar to those of the type strains of Mariniflexile species, but different from those of other phylogenetically related species. The DNA G+C content of strain TYO-10(T) was determined to be 35.9 mol%. The differential phenotypic properties, together with the phylogenetic distinctiveness, revealed that strain TYO-10(T) is separated from other Mariniflexile species. On the basis of the data presented, strain TYO-10(T) is considered to represent a novel species of the genus Mariniflexile, for which the name Mariniflexile ostreae sp. nov. is proposed. The type strain is TYO-10(T) (= KCTC 42113(T) = CECT 8622(T)).

A taxonomic study was carried out on strain 22II-S11-z7(T), which was isolated from the surface seawater of the Atlantic Ocean. The bacterium was found to be Gram-negative, oxidase negative and catalase positive, long-rod shaped, and gliding. Growth was observed at salinities of 1-5 % and at temperatures of 10-41 °C. The isolate was capable of hydrolysing gelatin and Tween 80 and able to reduce nitrate to nitrite, but unable to degrade aesculin. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 22II-S11-z7(T) belongs to the genus Aquimarina, with highest sequence similarity to Aquimarina megaterium XH134(T) (98.31 %), followed by Aquimarina macrocephali JAMB N27(T) (96.59 %); other species of the genus Aquimarina shared 93.63-96.08 % sequence similarity. The ANI value between strain 22II-S11-z7(T) and A. megaterium XH134(T) was found to be 91.86-91.81 %. The DNA-DNA hybridization estimated value between strain 22II-S11-z7(T) and A. megaterium XH134(T) was 47.7 ± 2.6 %. The principal fatty acids were identified as Summed Feature 3 (C16:1 ω7c/ω6c, as defined by the MIDI system; 8.1 %), SummedFeature 9 (iso-C17:1 ω7c/C16:110-methyl; 6.8 %), iso-C15:0 G (11.3 %), iso-C15:0 (24.9 %), iso-C16:0 (5.7 %), C16:0 (5.2 %), iso-C15:0 3OH (6.4 %) and iso-C17:0 3OH (21.5 %). The G+C content of the chromosomal DNA was determined to be 32.99 mol %. The respiratory quinone was determined to be MK-6 (100 %). Phosphatidylethanolamine, two unidentified aminolipids, five unidentified phospholipids and two unidentified lipids were found to be present. The combined genotypic and phenotypic data show that strain 22II-S11-z7(T) represents a novel species within the genus Aquimarina, for which the name Aquimarina atlantica sp. nov. is proposed, with the type strain 22II-S11-z7(T) (=MCCC 1A09239(T) = KCTC 42003(T)).

A Gram-negative, strictly aerobic, pale-yellow pigmented, rod-shaped bacterium designated A4O-5(T) was isolated from a red coloured marine alga (Chondrus ocellatus Holmes). Phylogenetic analyses based on the 16S rRNA gene sequence indicated that the new strain was affiliated with the family Flavobacteriaceae and shared approximately 90 % sequence similarity with Leptobacterium flavescens YM3-0301(T) and Gangjinia marincola GJ16(T). The strain could be differentiated phenotypically from the related members of the family Flavobacteriaceae. The major fatty acids of strain A4O-5(T) were identified as iso-C15:0, iso-C17:0 3-OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c). A complex polar lipid profile was present consisting of phosphatidylethanolamine, an unidentified phospholipid, three unidentified amino lipids and an unidentified lipid. The DNA G+C content of the strain was determined to be 41.9 mol% and the major respiratory quinone was identified as menaquinone 6 (MK-6). From the distinct phylogenetic position and combination of genotypic and phenotypic characteristics, the strain is considered to represent a novel genus in the family Flavobacteriaceae, for which the name Citreitalea marina gen. nov., sp. nov. is proposed. The type strain of C. marina is A4O-5(T) (=KCTC 32483(T)=NBRC 109918(T)).

Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is a widespread disease of amphibians responsible for population declines and extinctions. Some bacteria from amphibians' skins produce antimicrobial substances active against Bd. Supplementing populations of these cutaneous antifungal bacteria might help manage chytridiomycosis in wild amphibians. However, the activity of protective bacteria may depend upon environmental conditions. Biocontrol of Bd in nature thus requires knowledge of how environmental conditions affect their anti-Bd activity. For example, Bd-driven amphibian declines have often occurred at temperatures below Bd's optimum range. It is possible these declines occurred due to reduced anti-Bd activity of bacterial symbionts at cool temperatures. Better understanding of the effects of temperature on chytridiomycosis development could also improve risk evaluation for amphibian populations yet to encounter Bd. We characterized, at a range of temperatures approximating natural seasonal variation, the anti-Bd activity of bacterial symbionts from the skins of three species of rainforest tree frogs (Litoria nannotis, Litoria rheocola, and Litoria serrata). All three species declined during chytridiomycosis outbreaks in the late 1980s and early 1990s and have subsequently recovered to differing extents. We collected anti-Bd bacterial symbionts from frogs and cultured the bacteria at constant temperatures from 8 °C to 33 °C. Using a spectrophotometric assay, we monitored Bd growth in cell-free supernatants (CFSs) from each temperature treatment. CFSs from 11 of 24 bacteria showed reduced anti-Bd activity in vitro when they were produced at cool temperatures similar to those encountered by the host species during population declines. Reduced anti-Bd activity of metabolites produced at low temperatures may, therefore, partially explain the association between Bd-driven declines and cool temperatures. We show that to avoid inconsistent antifungal activity, bacteria evaluated for use in chytridiomycosis biocontrol should be tested over a range of environmental temperatures spanning those likely to be encountered in the field.