Endozoicomonas atrinae sp. nov., a bacterium isolated from the intestine of a comb pen shell Atrina pectinata.

Int J Syst Evol Microbiol. 2014 Apr 14;

Authors: Hyun DW, Shin NR, Kim MS, Oh SJ, Kim PS, Whon TW, Bae JW

Abstract
A novel strain, designated strain WP70T, was isolated from the gut of a comb pen shell (Atrina pectinata) collected from the southern sea of Yeosu in Korea. The isolate was Gram-stain-negative, aerobic, non-motile and rod-shaped. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain WP70T belongs to the genus Endozoicomonas. The highest level of sequence similarity (98.4%) was shared with Endozoicomonas elysicola. Optimal growth occurred in 2 % (w/v) NaCl at 30 °C and at pH 7. The major cellular fatty acids were summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), summed feature 8 (C18:1 ω7c and/or C18:1 ω6c) and C16:0. The main respiratory quinone was ubiquinone Q-9. The polar lipids comprised phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, three unidentified phospholipids, an unidentified aminolipid, an unidentified amino-phospholipid and an unidentified lipid. The genomic DNA G+C content was 50.5 mol% and DNA-DNA hybridization values indicated <11 % genomic relatedness to the closest phylogenetic species. Physiological, biochemical, chemotaxonomic and genotypic analyses indicated that strain WP70T represents a novel species of Endozoicomonas, for which the name Endozoicomonas atrinae sp. nov. is proposed. The type strain is WP70T (= KACC 17474T = JCM 18190T).

PMID: 24733175 [PubMed - as supplied by publisher]

Related Articles

Effects of a dietary β-(1,3)(1,6)-D-glucan supplementation on intestinal microbial communities and intestinal ultrastructure of mirror carp (Cyprinus carpio L.).

J Appl Microbiol. 2013 Nov;115(5):1091-106

Authors: Kühlwein H, Emery MJ, Rawling MD, Harper GM, Merrifield DL, Davies SJ

Abstract
AIM: To assess the effects of dietary Saccharomyces cerevisiae β-(1,3)(1,6)-D-glucan supplementation (MacroGard(®)) on mirror carp (Cyprinus carpio L.) intestinal microbiota and ultrastructure of the enterocyte apical brush border.
METHODS AND RESULTS: Carp were fed either a control diet or diets supplemented with 0.1, 1 or 2% w/w MacroGard(®). Culture-dependent microbiology revealed that aerobic heterotrophic bacterial levels were unaffected by dietary MacroGard(®) after 2 and 4 weeks. No effects were observed on the allochthonous lactic acid bacteria (LAB) populations at either time point; however, reduced autochthonous LAB populations were observed at week 4. PCR-DGGE confirmed these findings through a reduction in the abundance of autochthonous Lactococcus sp. and Vagococcus sp. in MacroGard(®)--fed fish compared with the control-fed fish. Overall, sequence analysis detected microbiota belonging to the phyla Proteobacteria, Firmicutes, Fusobacteria and unidentified uncultured bacteria. DGGE analyses also revealed that dietary MacroGard(®) reduced the number of observed taxonomical units (OTUs) and the species richness of the allochthonous microbiota after 2 weeks, but not after 4 weeks. In contrast, dietary MacroGard(®) reduced the number of OTUs, the species richness and diversity of the autochthonous microbiota after 2 weeks, and those parameters remained reduced after 4 weeks. Transmission electron microscopy revealed that intestinal microvilli length and density were significantly increased after 4 weeks in fish fed diets supplemented with 1% MacroGard(®).
CONCLUSIONS: This study indicates that dietary MacroGard(®) supplementation modulates intestinal microbial communities of mirror carp and influences the morphology of the apical brush border.
SIGNIFICANCE AND IMPACT OF THE STUDY: To the authors' knowledge, this is the first study to investigate the effects of β-(1,3)(1,6)-D-glucans on fish gut microbial communities, using culture-independent methods, and the ultrastructure of the apical brush border of the enterocytes in fish. This prebiotic-type effect may help to explain the mechanisms in which β-glucans provide benefits when fed to fish.

PMID: 23889777 [PubMed - indexed for MEDLINE]

Cellulomonas pakistanensis sp. nov., a novel moderately halotolerant Actinobacteria.

Int J Syst Evol Microbiol. 2014 Apr 14;

Authors: Ahmed I, Kudo T, Abbas S, Ehsan M, Iino T, Fujiwara T, Ohkuma M

Abstract
A rod-shaped, motile, facultative anaerobic and moderately halotolerant plant growth promoting actinobacterial strain, designated as NCCP-11T, was isolated from paddy grains. To delineate its taxonomic position, the strain was subjected to polyphasic characterization. Cells of strain NCCP-11T grew at 10-37°;C (optimum 28-32°C), at pH ranges of 6&-9 (optimum growth at pH 7) and in 0-12% (optimum 1-2%) NaCl (w/v) in broth medium. Based on 16S rRNA gene sequence analysis, strain NCCP-11T showed highest similarity to type strains of Cellulomonas hominis (98.99%), and Cellulomonas denverensis (98.09%) and less than 97% with other closely related taxa. The chemotaxonomic data [major menaquinone, MK-9(H4); cell wall peptidoglycan, type A4β; major fatty acids, anteiso-C15:0 (55.7%), C16:0 (15.1%) and C14:0 (12.8%) and anteiso-C17:0 (6.3%); major polar lipids, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol-mannosides and two unknown polar lipids] also supported the affiliation of strain NCCP-11T to genus Cellulomonas. The level of DNA-DNA relatedness between strain NCCP-11T and the two type strains mentioned above was less than 42.7 %. On the basis of DNA-DNA relatedness, physiological and biochemical characteristics and phylogenetic position, strain NCCP-11T can be differentiated from the validly published Cellulomonas species and thus represents as new species, for which the name, Cellulomonas pakistanensis sp. nov. is proposed with the type strain NCCP-11T (= DSM 24792T = JCM 18755T = KCTC 19798T).

PMID: 24733176 [PubMed - as supplied by publisher]

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Surfers are safe, crustaceans less so

The nearest most of us get to a sponge is when it's sitting on the bathroom shelf, but scientists at the Monterey Bay Aquarium Research Institute (MBARI) have found four new species of carnivorous sponge that are chomping their way through undersea life off the coast of California.…

Crates containing the Wankel T. rex have arrived at the Smithsonian National Museum of Natural History in Washington, shipped from the Museum of the Rockies, in Bozeman, Mt., near where it was first discovered in 1988. 

Mitochondria in hepatitis C-infected cells (bottom row) are self-destructing. The self-annihilation process explains the persistance and virulence of the virus in human liver cells. Researchers at the University of California, San Diego School of Medicine have identified a mechanism that explains why people with the hepatitis C virus get liver disease and why the virus is able to persist in the body for so long.

Ectomycorrhizal Cortinarius species participate in enzymatic oxidation of humus in northern forest ecosystems.

New Phytol. 2014 Apr 14;

Authors: Bödeker IT, Clemmensen KE, de Boer W, Martin F, Olson A, Lindahl BD

Abstract
In northern forests, belowground sequestration of nitrogen (N) in complex organic pools restricts nutrient availability to plants. Oxidative extracellular enzymes produced by ectomycorrhizal fungi may aid plant N acquisition by providing access to N in macromolecular complexes. We test the hypotheses that ectomycorrhizal Cortinarius species produce Mn-dependent peroxidases, and that the activity of these enzymes declines at elevated concentrations of inorganic N. In a boreal pine forest and a sub-arctic birch forest, Cortinarius DNA was assessed by 454-sequencing of ITS amplicons and related to Mn-peroxidase activity in humus samples with- and without previous N amendment. Transcription of Cortinarius Mn-peroxidase genes was investigated in field samples. Phylogenetic analyses of Cortinarius peroxidase amplicons and genome sequences were performed. We found a significant co-localization of high peroxidase activity and DNA from Cortinarius species. Peroxidase activity was reduced by high ammonium concentrations. Amplification of mRNA sequences indicated transcription of Cortinarius Mn-peroxidase genes under field conditions. The Cortinarius glaucopus genome encodes 11 peroxidases - a number comparable to many white-rot wood decomposers. These results support the hypothesis that some ectomycorrhizal fungi - Cortinarius species in particular - may play an important role in decomposition of complex organic matter, linked to their mobilization of organically bound N.

PMID: 24725281 [PubMed - as supplied by publisher]

A Paleozoic Stem Group to Mite Harvestmen Revealed through Integration of Phylogenetics and Development.

Curr Biol. 2014 Apr 9;

Authors: Garwood RJ, Sharma PP, Dunlop JA, Giribet G

Abstract
Successfully placing fossils in phylogenies is integral to understanding the tree of life. Crown-group Paleozoic members of the arachnid order Opiliones are indicative of ancient origins and one of the earliest arthropod terrestrialization events [1, 2]. Opiliones epitomize morphological stasis, and all known fossils have been placed within the four extant suborders [3-5]. Here we report a Carboniferous harvestman species, Hastocularis argusgen. nov., sp. nov., reconstructed with microtomography (microCT). Phylogenetic analysis recovers this species, and the Devonian Eophalangium sheari, as members of an extinct harvestman clade. We establish the suborder Tetrophthalmi subordo nov., which bore four eyes, to accommodate H. argus and E. sheari, the latter previously considered to be a phalangid [6-9]. Furthermore, embryonic gene expression in the extant species Phalangium opilio demonstrates vestiges of lateral eye tubercles. These lateral eyes are lost in all crown-group Phalangida, but are observed in both our fossil and outgroup chelicerate orders. These data independently corroborate the diagnosis of two eye pairs in the fossil and demonstrate retention of eyes of separate evolutionary origins in modern harvestmen [10-12]. The discovery of Tetrophthalmi alters molecular divergence time estimates, supporting Carboniferous rather than Devonian diversification for extant suborders and directly impacting inferences of terrestrialization history and biogeography. Multidisciplinary approaches integrating fossil and neontological data increase confidence in phylogenies and elucidate evolutionary history.

PMID: 24726154 [PubMed - as supplied by publisher]

Hypoxia, Blackwater and Fish Kills: Experimental Lethal Oxygen Thresholds in Juvenile Predatory Lowland River Fishes.

PLoS One. 2014;9(4):e94524

Authors: Small K, Kopf RK, Watts RJ, Howitt J

Abstract
Hypoxia represents a growing threat to biodiversity in freshwater ecosystems. Here, aquatic surface respiration (ASR) and oxygen thresholds required for survival in freshwater and simulated blackwater are evaluated for four lowland river fishes native to the Murray-Darling Basin (MDB), Australia. Juvenile stages of predatory species including golden perch Macquaria ambigua, silver perch Bidyanus bidyanus, Murray cod Maccullochella peelii, and eel-tailed catfish Tandanus tandanus were exposed to experimental conditions of nitrogen-induced hypoxia in freshwater and hypoxic blackwater simulations using dried river red gum Eucalyptus camaldulensis leaf litter. Australia's largest freshwater fish, M. peelii, was the most sensitive to hypoxia but given that we evaluated tolerances of juveniles (0.99±0.04 g; mean mass ±SE), the low tolerance of this species could not be attributed to its large maximum attainable body mass (>100,000 g). Concentrations of dissolved oxygen causing 50% mortality (LC50) in freshwater ranged from 0.25±0.06 mg l-1 in T. tandanus to 1.58±0.01 mg l-1 in M. peelii over 48 h at 25-26°C. Logistic models predicted that first mortalities may start at oxygen concentrations ranging from 2.4 mg l-1 to 3.1 mg l-1 in T. tandanus and M. peelii respectively within blackwater simulations. Aquatic surface respiration preceded mortality and this behaviour is documented here for the first time in juveniles of all four species. Despite the natural occurrence of hypoxia and blackwater events in lowland rivers of the MDB, juvenile stages of these large-bodied predators are vulnerable to mortality induced by low oxygen concentration and water chemistry changes associated with the decomposition of organic material. Given the extent of natural flow regime alteration and climate change predictions of rising temperatures and more severe drought and flooding, acute episodes of hypoxia may represent an underappreciated risk to riverine fish communities.

PMID: 24728094 [PubMed - as supplied by publisher]

Sarcocystis schneideri n. sp. (Sarcocystidae) infecting the barber skink Eumeces schneideri schneideri (Scincidae) Daudin, 1802. A light and ultrastructural study.

Parasitol Res. 2014 Apr 12;

Authors: Bashtar AR, Al Aal ZA, Maarouf W, Morsy K, Al Quraishy S

Abstract
The current study provides the first record of infection with Sarcocystis species in the barber skink Eumeces schneideri schneideri (Scincidae) captured from the north region of Egypt around the cities of El-Hamam and Al-Dabaa, Mersa Matruh Governorate, Egypt. Morphology of the parasite cysts was described using light and transmission electron microscopy. Five out of 80 (6.25 %) of the examined skinks were found to be infected. The infection was recorded firstly by light microscopy as spindle-shaped cysts embedded in the muscle tissue. The cysts were microscopic and measured 250-900 μm in length × 50-100 μm in width (mean, 575 × 75 μm). The validity of this species was confirmed by means of ultrastructural characteristics of the primary cyst wall (0.28 μm thick) which revealed the presence of irregularly shaped crowded and osmiophilic knob-like projections underlined by a thin layer of ground substance measuring 0.15-0.17 μm (mean, 0.16 μm). This layer consisted mainly of fine, dense homogenous granules enclosing the developing metrocytes and merozoites that usually contain nearly all the structures of the apical complex and fill the interior cavity of the cyst. Several septa derived from the ground substance divided the cyst into compartments. The merozoites were banana-shaped and measured 3-5 μm in length and 1.5-2.5 in width with centrally or posteriorly located nuclei. The morphological and morphometric data obtained during study were compared with those recorded previously from organisms within the Scincidae family. It was observed that this parasite possessed some distinguishing characteristics from the comparable species, which should be considered as a new species of the Sarcocystis genus, and the proposed name was Sarcocystis schneideri n. sp. with new host and locality records in Egypt.

PMID: 24728518 [PubMed - as supplied by publisher]

Survey on diversity of marine/saline anaerobic Heterolobosea (Excavata: Discoba) with description of seven new species.

Int J Syst Evol Microbiol. 2014 Apr 11;

Authors: Pánek T, Ptácková E, Cepicka I

Abstract
Diversity of anaerobic Heterolobosea (Excavata: Discoba) is only poorly understood, especially in marine environments. We have isolated and cultured 16 strains of anaerobic heteroloboseid amoebae and flagellates from brackish, marine and saline anoxic habitats worldwide. Phylogenetic analyses of SSU rDNA and light-microscopic observations showed that all the strains belong to Psalteriomonadidae, the main anaerobic lineage of Heterolobosea and that they represent eight species from genera Monopylocystis, Harpagon and Pseudoharpagon. Seven species are new and described here as Monopylocystis minor n. sp., M. robusta n. sp., M. elegans n. sp., M. disparata n. sp., Harpagon salinus n. sp., Pseudoharpagon longus n. sp., and P. tertius n. sp.. Amoebae, cysts, and the ultrastructure of the genus Pseudoharpagon are presented for the first time.

PMID: 24729392 [PubMed - as supplied by publisher]

A new species of Simulium (Gomphostilbia) (Diptera: Simuliidae) from Thailand, with keys to 11 species of the Simulium varicorne species-group.

J Med Entomol. 2014 Mar;51(2):314-22

Authors: Takaoka H, Srisuka W, Saeung A, Choochote W

Abstract
Simulium (Gomphostilbia) piroonae sp. nov. is described on the basis of females, males, pupae, and mature larvae collected in Mae Hong Son Province, Thailand. This new species is placed in the chumpornense subgroup of the varicorne species-group in the subgenus Gomphostilbia by having the antenna with eight flagellomeres, the pleural membrane bare, the female subcosta lacking hairs, and the pupal gill basally divided into two somewhat inflated branches. It is distinguished from all 10 known species of this group by the pupal gill with six filaments. Keys to identify 11 species of the varicorne species-group are provided for females, males, pupae, and mature larvae.

PMID: 24724279 [PubMed - in process]

Mucilaginibacter koreensis sp. nov., isolated from leaf mold.

Int J Syst Evol Microbiol. 2014 Apr 11;

Authors: Park CS, Han K, Ahn TY

Abstract
A Gram-staining-negative, strictly aerobic, rod-shaped, pale-pink pigmented bacterial strain, designated TF8T, was isolated from leaf mold in Cheonan, Republic of Korea. Its taxonomic position was determined through a polyphasic approach. Optimal growth occurred on R2A agar without NaCl supplementation, at 25-28°C and at pH 6.0-7.0. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain TF8T belongs to the genus Mucilaginibacter in the family Sphingobacteriaceae. The sequence similarity between 16S rRNA genes of strain TF8T and the type strains of other Mucilaginibacter species ranged from 92.1 to 94.7 %. The closest relatives of strain TF8T were Mucilaginibacter lutimaris BR-3T (94.7%), M. soli R9-65T (94.5%), M. litoreus BR-18T (94.5%), M. rigui WPCB133T (94.0%) and M. daejeonensis Jip 10T (93.8%). The major isoprenoid quinone was MK-7 and the major cellular fatty acids were iso-C15:0 (33.0%), summed feature 3 (C16:1ω7c and/or C16:1ω6c; 24.8%) and summed feature 8 (C18:1ω7c and/or C18:1ω6c; 13.0%). The major polar lipids of TF8T were phosphatidylethanolamine and three unidentified aminophospholipids. The G+C content of the genomic DNA was 46.2 mol%. On the basis of the data presented here, strain TF8T is considered to represent a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter koreensis sp. nov. is proposed. The type strain is TF8T (=KACC 17468T =JCM 19323T).

PMID: 24729393 [PubMed - as supplied by publisher]