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111.
Alida Frankline Hasiniaina Ute Radespiel Sharon E. Kessler Mamy Rina Evasoa Solofonirina Rasoloharijaona Blanchard Randrianambinina Elke Zimmermann Sabine Schmidt Marina Scheumann 《Ecology and evolution》2020,10(8):3784-3797
Acoustic phenotypic variation is of major importance for speciation and the evolution of species diversity. Whereas selective and stochastic forces shaping the acoustic divergence of signaling systems are well studied in insects, frogs, and birds, knowledge on the processes driving acoustic phenotypic evolution in mammals is limited. We quantified the acoustic variation of a call type exchanged during agonistic encounters across eight distinct species of the smallest‐bodied nocturnal primate radiation, the Malagasy mouse lemurs. The species live in two different habitats (dry forest vs. humid forest), differ in geographic distance to each other, and belong to four distinct phylogenetic clades within the genus. Genetically defined species were discriminated reliably on the phenotypic level based on their acoustic distinctiveness in a discriminant function analysis. Acoustic variation was explained by genetic distance, whereas differences in morphology, forest type, or geographic distance had no effect. The strong impact of genetics was supported by a correlation between acoustic and genetic distance and the high agreement in branching pattern between the acoustic and molecular phylogenetic trees. In sum, stochastic factors such as genetic drift best explained acoustic diversification in a social communication call of mouse lemurs. 相似文献
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Sharon A. Appleyard Safia Maher John J. Pogonoski Stephen J. Bent Xin-Yi Chua Annette McGrath 《Journal of fish biology》2021,98(5):1421-1432
Natural history collections are repositories of biodiversity and are potentially used by molecular ecologists for comparative taxonomic, phylogenetic, biogeographic and forensic purposes. Specimens in fish collections are preserved using a combination of methods with many fixed in formalin and then preserved in ethanol for long-term storage. Formalin fixation damages DNA, thereby limiting genetic analyses. In this study, the authors compared the DNA barcoding and identification success for frozen and formalin-fixed tissues obtained from specimens in the CSIRO Australian National Fish Collection. They studied 230 samples from fishes (consisting of >160 fish species). An optimized formalin-fixed, paraffin-embedded DNA extraction method resulted in usable DNA from degraded tissues. Four mini barcoding assays of the mitochondrial DNA (mtDNA) were characterized with Sanger and Illumina amplicon sequencing. In the good quality DNA (without exposure to formalin), up to 88% of the specimens were correctly matched at the species level using the cytochrome oxidase subunit 1 (COI) mini barcodes, whereas up to 58% of the specimens exposed to formalin for less than 8 weeks were correctly identified to species. In contrast, 16S primers provided higher amplification success with formalin-exposed tissues, although the COI gene was more successful for identification. Importantly, the authors found that DNA of a certain size and quality can be amplified and sequenced despite exposure to formalin, and Illumina sequencing provided them with greater power of resolution for taxa identification even when there was little DNA present. Overall, within parameter constraints, this study highlights the possibilities of recovering DNA barcodes for identification from formalin-fixed fish specimens, and the authors provide guidelines for when successful identification could be expected. 相似文献
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Tra-My N. Duong Thanh-Van Le Khanh-Linh H. Tran Phuong-Tuyen Nguyen Bich-Phuong T. Nguyen Thu-Anh Nguyen Huong-Lan P. Nguyen Bich-Ngoc T. Nguyen Matthew C. Fisher Johanna Rhodes Guy Marks Greg J. Fox Sharon C.-A. Chen Michael G. Walsh Vanessa R. Barrs Jessica Talbot Catriona L. Halliday Tania C. Sorrell Jeremy N. Day Justin Beardsley 《Environmental microbiology》2021,23(12):7632-7642
Azole-resistant environmental Aspergillus fumigatus presents a threat to public health but the extent of this threat in Southeast Asia is poorly described. We conducted environmental surveillance in the Mekong Delta region of Vietnam, collecting air and ground samples across key land-use types, and determined antifungal susceptibilities of Aspergillus section Fumigati (ASF) isolates and azole concentrations in soils. Of 119 ASF isolates, 55% were resistant (or non-wild type) to itraconazole, 65% to posaconazole and 50% to voriconazole. Azole resistance was more frequent in A. fumigatus sensu stricto isolates (95%) than other ASF species (32%). Resistant isolates and agricultural azole residues were overrepresented in samples from cultivated land. cyp51A gene sequence analysis showed 38/56 resistant A. fumigatus sensu stricto isolates carried known resistance mutations, with TR34/L98H most frequent (34/38). 相似文献
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Calf thymus DNA containing defined levels of 8-hydroxy-2′-deoxyguanosine (8-oxodG) was prepared by treatment with visible light in the presence of photosensitiser Ro 19-8022. The DNA was checked for stability; after freeze-drying, the amount of 8-oxodG did not increase during 6 weeks' storage at room temperature. However, freeze-drying itself can introduce additional oxidative damage. Two enzymic hydrolysis regimes (DNase I, phosphodiesterases I and II, and alkaline phosphatase; or P1 nuclease and alkaline phosphatase) give similar values for 8-oxodG. 相似文献
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R. F. McGregor M. S. Sharon M. Atkinson D. E. Johnson 《Preparative biochemistry & biotechnology》2013,43(6):403-419
The isolation of polyamines from urinary hydrolysates in a sufficiently pure state for subsequent analysis by gas chromatography has proved to be difficult. However, by using columns of Porapak-Q and ion-exchange resins, urinary hydrolysates are readily purified and formation of trifluoroacetyl derivatives of polyamines proceeds in high yield without carryover of artifacts in the gas chromatographic elution profile. Good yields from the trifluoroacetylation reaction are not achieved if large quantities of salts or urinary pigments are present. By obtaining the polyamine carbonates in the final stages of the method described, the trifluoroacetylation reaction yields excellent derivatives of nanogram or microgram amounts, particularly after standing over-night at room temperature. The procedure described in detail should permit routine urinary polyamine analysis where rapidity, ease of handling many samples, freedom from complications and artifacts are a consideration. The recent reports by Russell1, 2 that the urinary excretion of polyamines are greatly elevated in cancer patients has stimulated interest in these compounds as possible biological “markers” for the diagnosis of cancer. The polyamines usually considered are: putrescine, 1, 4-diaminobutane; cadaverine, 1, 5-diaminopentane; spermidine, and spermine. An extensive literature has developed over the last 50 years concerning the isolation and determination of polyamines including many excellent reviews. 3–5 However, the isolation and determination of small quantities of polyamines from biological sources has proven to be difficult. This has led to conflicting conclusions among investigators as to which polyamine is the major excretion product in the urine of cancer patients. 2, 6, 7, 8 The following report presents in detail a new procedure of isolation of urinary polyamines in high yield and pure state that facilitates quantitation of these amines by gas chromatography. 相似文献