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An opilioacarid mite in Cretaceous Burmese amber.
Naturwissenschaften. 2014 Sep;101(9):759-63
Authors: Dunlop JA, de Oliveira Bernardi LF
Abstract A fossil opilioacarid mite (Parasitiformes: Opilioacarida) in Burmese amber is described as ?Opilioacarus groehni sp. nov. This ca. 99 Ma record (Upper Cretaceous: Cenomanian) represents only the third fossil example of this putatively basal mite lineage, the others originating from Eocene Baltic amber (ca. 44-49 Ma). Our new record is not only the oldest record of Opilioacarida, but it is also one of the oldest examples of the entire Parasitiformes clade. The presence of Opilioacarida-potentially Opiloacarus-in the Cretaceous of SE Asia suggests that some modern genus groups were formerly more widely distributed across the northern hemisphere, raising questions about previously suggested Gondwanan origins for these mites.
PMID: 25027588 [PubMed - indexed for MEDLINE]
Nitrosospira lacus sp. nov., a psychrotolerant ammonia-oxidizing bacterium from sandy lake sediment.
Int J Syst Evol Microbiol. 2014 Oct 21;
Authors: Urakawa H, Garcia JC, Nielsen JL, Le VQ, Kozlowski JA, Stein LY, Lim CK, Pommerening-Röser A, Martens-Habbena W, Stahl DA, Klotz MG
Abstract A Gram-negative, spiral chemolithotrophic ammonia-oxidizing bacterium, designated APG3T was isolated into pure culture from sandy lake sediment collected from Green Lake, Seattle Washington, USA. Phylogenetic analyses based on 16S rRNA genes showed that strain APG3T belongs to the cluster 0 Nitrosospira, which is presently not represented by described species, with Nitrosospira multiformis (cluster 3) as its closest validated species (identity of 98.6 %). Strain APG3T grows at 4°C but cannot grow at 35°C, indicating that this bacterium is psychrotolerant. Remarkably, the strain was able to grow at a wide range of pH (pH 5-9), which was greater than the range of studied ammonia-oxidizing bacteria in pure culture. The G+C content of the APG3T genome is 53.5%, which is similar to N. multiformis ATCC25196 (53.9%) but higher than that of N. europaea (50.7%) and N. eutropha (48.5%). The average nucleotide identity (ANI) calculated for the genomes of strain APG3T and N. multiformis was 75.45%, a significantly lower value than 95% ANI, which corresponds to 70% species level cut-off based on DNA-DNA hybridization. Overall polyphasic taxonomy study indicated that strain APG3T represents a new species in the genus Nitrosospira for which the name Nitrosospira lacus sp. nov. is proposed (type strain APG3T = NCIMB 14869T = LMG 27536T = ATCC BAA-2542T).
PMID: 25336720 [PubMed - as supplied by publisher]
Thiogranum longum gen. nov., sp. nov., a novel obligately chemolithoautotrophic sulfur-oxidizing bacterium of the family Ectothiorhodospiraceae isolated from a hydrothermal field on Suiyo Seamount, and an emended description of the genus Thiohalomonas.
Authors: Mori K, Suzuki KI, Yamaguchi K, Urabe T, Hanada S
Abstract A novel obligately chemolithoautotrophic sulfur-oxidizing bacterial strain, designated strain gps52(T), was isolated from a rock sample collected near the hydrothermal vents of the Suiyo Seamount in the Pacific Ocean. The cells possessed a Gram-negative type cell wall and contained menaquinone-8(H4) and menaquinone-9(H4) as respiratory quinones, and C16:1?7cis, C16:0, and C18:1?7cis as major cellular fatty acids. Neither storage compounds nor extensive internal membranes were observed in the cells. Strain gps52T grew using carbon dioxide fixation and oxidation of inorganic sulfur compounds with oxygen as electron acceptor. The optimum growth was observed at 32°C, pH 6.6 and 3% NaCl. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain gps52T belongs to the family Ectothiorhodospiraceae and is different from any other known bacteria, with sequence similarities of less than 93%. Based on phenotypic and phylogenetic findings, the isolate is considered to represent a new genus and species in the family Ectothiorhodospiraceae, and the name Thiogranum longum gen. nov., sp. nov. is proposed for strain gps52(T) (=NBRC 101260(T) = DSM 19610(T)).
PMID: 25336721 [PubMed - as supplied by publisher]
Parablastomonas arctica gen. nov., sp. nov., a bacterium isolated from high Arctic glacial till.
Authors: Ren L, Chang X, Jiang F, Kan W, Qu Z, Qiu X, Fang C, Peng F
Abstract A pale yellow pigmented, aerobic bacterium, strain M0-2T, was isolated from a till sample. Its taxonomic position was investigated by using a polyphase approach. Cells are Gram-stain-negative, rod-shaped and motile. Cells reproduce by budding or asymmetric cell division. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain M0-2T belonged to the family Sphingomonadaceae and was closely related to Novosphingobium species (96.4-92.0%), Blastomonas species (94.6%), Sphingopyxis witflariensis W-50T (94.0%), Sphingosinicella soli KSL-125T (93.6%) and Sphingomonas astaxanthinifaciens TDMA-17T (93.5%). Ubiquinone-10 (Q-10) was the predominant respiratory quinone. The major fatty acids were summed feature 8 (comprising C18:1 ?7c and/or C18:1 ?6c, 31.9%), summed feature 3 (comprising C16:1 ?7c and/or C16:1 ?6c, 19.8%) and C14:0 2-OH (8.9%). Sphingoglycolipid, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine were the major polar lipids. Spermidine was the major polyamine observed in the cell. The genomic DNA G+C content was 47.5 mol%. Based on the phylogenetic relationship, the low DNA G+C content compared with most other genera of the family Sphingomonadaceae and combined with phenotypic and chemotaxonomic data, strain M0-2T is considered to represent a novel species in a new genus in the family Sphingomonadaceae for which the name Parablastomonas arctica gen. nov., sp. nov. is proposed. The type strain of Parablastomonas arctica gen. nov., sp. nov. is M0-2T (=CCTCC AB 2012968 T = NRRL B-59110T).
PMID: 25336722 [PubMed - as supplied by publisher]
Bombella intestini gen. nov., sp. nov., a novel acetic acid bacterium isolated from bumble bee crop.
Authors: Li L, Praet J, Borremans W, Nunes OC, Manaia CC, Cleenwerck IM, Meeus I, Smagghe G, De Vuyst L, Vandamme PA
Abstract In the frame of a bumble bee gut microbiota study, acetic acid bacteria (AAB) were isolated using a combination of direct isolation methods and enrichment procedures. MALDI-TOF MS profiling of the isolates and a comparison of these profiles with profiles of established AAB species identified most isolates as Asaia astilbes or as "Commensalibacter intestini", except for two isolates (R-52486 and LMG 28161T) that showed an identical profile. A nearly complete 16S rRNA gene sequence of LMG 28161T was determined and showed the highest pairwise similarity to Saccharibacter floricola (96.5 %), which corresponded with genus level divergence in the Acetobacteraceae family. Isolate LMG 28161T was subjected to whole-genome shotgun sequencing; a 16S-23S rRNA internal transcribed spacer (ITS) sequence as well as partial sequences of the housekeeping genes dnaK, groEL and rpoB were extracted for phylogenetic analyses. The data obtained confirmed that this isolate is best classified into a novel genus in the family Acetobacteraceae. Its DNA G+C content was 54.9 mol%. The fatty acid compositions of R-52486 and LMG 28161T were similar to those of established AAB species [with C18:1?7c (43.3 %) as major component], but the amounts of fatty acids such as C19:0 cyclo ?8c, C14:0 and C14:0 2-OH enabled to differentiate them. The major ubiquinone was Q-10. Both isolates could also be differentiated from the known genera of AAB by means of biochemical characteristics, such as their lack of ability to oxidize ethanol to acetic acid, negligible acid production from melibiose, and notable acid production from D-fructose, sucrose and D-mannitol. In addition, they produced 2-keto-D-gluconic acid, but not 5-keto-D-gluconic acid from D-glucose. Therefore, the name Bombella intestini is proposed for this new taxon, with LMG 28161T (= DSM 28636T) as the type strain.
PMID: 25336723 [PubMed - as supplied by publisher]
Read more of this story at Slashdot.
Nearly 50 years after discovering Deinocheirus mirificus, paleontologists have established a complete picture of the 36-foot-long dinosaur.
Morphologic, cytometric and functional characterization of the common octopus (Octopus vulgaris) hemocytes.
Dev Comp Immunol. 2014 May;44(1):50-8
Authors: Castellanos-Martínez S, Prado-Alvarez M, Lobo-da-Cunha A, Azevedo C, Gestal C
Abstract The hemocytes of Octopus vulgaris were morphologically and functionally characterized. Light and electron microscopy (TEM and SEM), and flow cytometry analyses revealed the existence of two hemocyte populations. Large granulocytes showed U-shaped nucleus, a mean of 11.6 ?m±1.2 in diameter with basophilic granules, polysaccharide and lysosomic deposits in the cytoplasm. Small granulocytes measured a mean of 8.1 ?m±0.7 in diameter, and have a round nucleus occupying almost the entire cell and few or not granules in the cytoplasm. Flow cytometry analysis showed that large granulocytes are the principal cells that develop phagocytosis of latex beads (rising up to 56%) and ROS after zymosan stimulation. Zymosan induced the highest production of both ROS and NO. This study is the first tread towards understanding the O. vulgaris immune system by applying new tools to provide a most comprehensive morpho-functional study of their hemocytes.
PMID: 24296436 [PubMed - indexed for MEDLINE]