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1.
A new subgenus of Polia, Metallopolia subgen. n., two new species (Polia (Metallopolia) dysgnorima sp. n. and P. (M.) metagnorima sp. n.) from China (Sichuan, Yunnan, Gansu), and a new subspecies, P. (M.) subviolacea kanchenjunga ssp. n. from Nepal and SE Tibet (Sikkim) are described. Habitus, antennae, male and female genitalia of all Metallopolia species are characterised, depicted and compared with the related species. 相似文献
2.
When two tree species co-occur, decomposition and nitrogen (N) release from the foliage litter depend on two factors: the
forest floor conditions under each canopy type and the species composition of the litter. We conducted an experiment using
fir and oak to answer several questions regarding decomposition beneath canopies of the two species and the effects of litter
species composition on decomposition. We compared the rates of decomposition and N release from three different litters (fir
needle, oak leaf, and a mixture of the two) in 1-mm-mesh litterbags on the forest floor under three different canopies (a
40-year-old fir plantation, large oak trees, and mixed fir and oak trees) in Hokkaido, Japan, over a 2-year period. Beneath
each of these canopy types, the litter decomposition rate and percentage of N remaining in the litterbags containing a mixture
of fir and oak litter were not significantly different from the expected values calculated for litterbags containing litter
from a single tree species. Oak leaf litter decomposed significantly faster than fir needle litter beneath each canopy type.
The litter decomposition rate was significantly higher beneath the fir canopy than under the oak canopy, and was intermediate
under the mixed canopy of fir and oak. No net N release, that is, a decrease in the total N compared to the original amount,
was detected from fir litter under each canopy type or from oak leaf litter beneath the oak canopy. N increased over the original
amount in the fir litter beneath the oak canopy and the mixed canopy of fir and oak, but N was released from the oak litter
under the fir canopy and the mixed canopy of fir and oak. These results suggest that oak leaf litter blown onto fir forest
floor enhances nutrient cycling, and this might be a positive effect of a mixed stand of conifer and broad-leaved trees. 相似文献
3.
Gamal H. Osman Raya Soltane Ibrahim Saleh Hussein H. Abulreesh Khaled S. Gazi Ibrahim A. Arif Ahmed M. Ramadan Hussien F. Alameldin Yehia A. Osman Mamdouh Idriss 《Saudi Journal of Biological Sciences》2019,26(5):1078-1083
Black cutworm (BCW) is an economically important lepidopteran insect. The control of this insect by a Bt toxin and the understanding of the interaction between the Bt toxin and its receptor molecule were the objectives of this research work. A gene coding for a Vip3A receptor molecule was identified, characterized, and cloned, from the brush border membrane vesicles (BBMV) of the BCW. The nucleotide sequence analysis of the cloned putative Vip3A-receptor gene revealed that the gene was 1.3-kb long and exhibited no homology with any gene in the gene bank. We succeeded in identifying and characterizing most of the Vip3A-receptor gene sequence; and the nucleotide sequence analysis of the cloned putative Vip3A-receptor gene (accession no. KX858809) revealed about 92% of the expected sequence was recovered, which exhibited no homology with any gene in the GenBank. 相似文献
4.
Muyiwa Ajoke Akindolire Ajay Kumar Collins Njie Ateba 《Saudi Journal of Biological Sciences》2018,25(7):1348-1355
Food borne diseases are a major public health concern worldwide. Staphylococcus aureus is one of the potential food borne pathogens which causes nosocomial and community acquired infections. In the present study, 74 representative strains of S. aureus isolated and characterized in previous study from different milk samples were subjected to random amplified polymorphic DNA (RAPD) polymerase chain reaction (PCR) and enterobacterial repetitive intergenic consensus (ERIC)-PCR to generate fingerprints to determine the genetic relationships of the isolated strains. A total of 20 RAPD patterns were generated and the number of amplified fragments obtained ranged from 0 to 8 with molecular weight ranging from 250 to 2000 bp. A dendrogram based on fingerprinting pattern grouped isolates into twelve major clusters (I–XII). In the case of ERIC-PCR 9 banding patterns were obtained with amplicons ranging from 1 to 8 and band sizes ranging from 250 to 2000 bp. A total of four major clusters (I–IV) were observed in the dendrogram based on ERIC fingerprints. The discrete banding patterns obtained both from ERIC-PCR and RAPD-PCR showed remarkably the genetic diversity of S. aureus. The findings of this study indicate that raw, bulk and pasteurized milk in the North-West Province was contaminated with toxigenic and multi-drug resistant S. aureus strains. This emphasizes the need to implement appropriate control measures to reduce contamination as well as the spread of virulent S. aureus strains to reduce the burden of disease in humans. 相似文献
5.
Sinodima gen. nov., a new genus in the click-beetle tribe Dimini Candèze, 1863 from the mountains in Hunan, China, is described and figured here to accommodate S. jenisi sp. nov. The new genus is easily recognizable from all other Dimini by the following combination of characters: short antennomeres II and III; transverse pronotum with inconspicuous anterior angles; arcuate prosternal process; mesoventrite with straight frontal margin and oblique and straight sides; absent hind wings; and absent sclerites or spines in the bursa copulatrix. Additionally, we compare Sinodima gen. nov. with the morphologically similar genera, and discuss the systematic position of this genus within Dimini.www.zoobank.org/urn:lsid:zoobank.org:pub:91F22A25-E1F1-4EC4-B3EF-5D632B83FDE5 相似文献
6.
7.
Bristlemouths of the genus Cyclothone are currently regarded as the most abundant vertebrates on Earth. The fossil record seems to suggest that these fishes diversified during the Miocene in the Pacific Ocean, but there is no evidence of their presence in the Miocene of the Atlantic Ocean and Mediterranean basin. A new bristlemouth, Cyclothone gaudanti sp. nov. (Teleostei, Stomiiformes, Gonostomatidae), is described herein based on 16 specimens from the Upper Miocene Makrilia Formation (late Tortonian of Crete, Greece). The small sized species is characterized by light pigmentation, 30–31 (14–15 + 15–16) vertebrae, dorsal fin with 10–13 rays, anal fin with 10–14 rays, premaxilla bearing seven closely spaced teeth, maxilla with 42–55 teeth, epipleurals, and autogenous parhypural. The presence of epipleurals appears to be unique of this Miocene species, and the re-establishment of this ancestral character state may be possibly interpreted as related to a phylogenetic character reversal. Morphological and paleoecological considerations suggest that this species possibly inhabited the upper mesopelagic layer, at depths ranging from 2–300 and 500 meters. 相似文献
8.
Monica Modesto Edoardo Puglisi Andrea Bonetti Samanta Michelini Caterina Spiezio Camillo Sandri Barbara Sgorbati Lorenzo Morelli Paola Mattarelli 《Systematic and applied microbiology》2018,41(6):593-603
Four novel Gram-stain-positive, non spore forming and fructose-6-phosphate phosphoketolase-positive strains were isolated from the faeces of a cotton top tamarin (Saguinus oedipus) and an emperor tamarin (Saguinus imperator). Phylogenetic analyses based on 16S rRNA revealed that bifidobacterial strains TRE 1T exhibit close phylogenetic relatedness to Bifidobacterium catulorum DSM 103154 (96.0%) and Bifidobacterium tissieri DSM 100201 (96.0%); TRE DT and TRE HT were closely related to Bifidobacterium longum subsp. longum ATCC 15708T with similarity values of 97.4% and 97.5%, respectively; TRI 7T was closely related to Bifidobacterium tissieri DSM 100201 (96.0%). The Average Nucleotide Identity (ANI) and in silico DDH (isDDH) analysis with closest neighbour supported an independent phylogenetic position of all strains with values ranged from 74 to 85% for ANI and from 24 to 28% for isDDH. DNA base composition of the four strains was in the range of 58.3–63.5 mol% G + C. Based on the phylogenetic, genotypic and phenotypic data, the strains TRE 1T, TRE DT, TRE HT and TRI 7T clearly represent four novel taxa within the genus Bifidobacterium for which the names Bifidobacterium primatium sp. nov. (type strain TRE 1T = DSM 100687T = JCM 30945T), Bifidobacterium scaligerum sp. nov. (type strain TRE DT = DSM 103140T = JCM 31792T), Bifidobacterium felsineum sp. nov. (type strain TRE HT = DSM 103139T = JCM 31789T) and Bifidobacterium simiarum sp. nov. (type strain TRI 7T = DSM 103153T = JCM 31793) are proposed. 相似文献
9.
Zaibao Zhang Yilin Zhao Xiaobing Feng Zhaoyi Luo Shuwei Kong Chi Zhang Andong Gong Hongyu Yuan Lin Cheng Xiangnan Wang 《Genomics》2019,111(4):619-628
Reactive oxygen species (ROS) are versatile signaling molecules in sensing stresses and play critical roles in signaling and development. Plasma membrane NADPH oxidases (NOXs) are key producers of ROS, and play important roles in the regulation of plant-pathogen interactions. Here, we performed a comprehensive analysis of the NOX gene family in the soybean genome (Glycine max) and 17 NOX (GmNOX) genes were identified. Structural analysis revealed that the GmNOX proteins in soybean were as conserved as those in other plants. 8 duplicated gene pairs were formed by a Glycine-specific whole-genome duplication (WGD) event approximately 13 million years ago (Mya). The Ka/Ks ratios of GmNOX genes ranged from 0.04 to 0.28, suggesting that the GmNOX family had undergone purifying selection in soybean. Gene expression patterns showed different expression of these duplicate genes, suggesting that the GmNOXs were retained by substantial subfunctionalization during the soybean evolutionary processes. Subsequently, the expression of GmNOXs in response to drought and phytohormones were characterized via qPCR. Importantly, four GmNOXs showed strong expression in nodules, pointing to their probable involvement in nodulation. Thus, our results shed light on the evolutionary history of this family in soybean and contribute to the functional characterization of GmNOX genes in soybean. 相似文献
10.
Two associated incomplete thyreophoran dorsal vertebrae from the Callovian Marnes de Dives Formation of the Vaches Noires cliffs, on the Normandy coast, are referred to an indeterminate stegosaur that appears to be different from Lexovisaurus, previously reported from the Callovian of western France. These vertebrae are the first evidence of thyreophorans from the Vaches Noires and complement the dinosaur assemblage from this locality, which hitherto consisted of several theropod taxa and an indeterminate sauropod. The dinosaur record from the Vaches Noires is heavily dominated by theropods and this imbalance is difficult to explain. A possible explanation may be that the dinosaur sample from the Vaches Noires is too small to be statistically significant and representative of the original faunal assemblage from which it is derived. 相似文献
11.
Accumulation of arachidonic acid-rich triacylglycerols in the microalga Parietochloris incisa (Trebuxiophyceae,Chlorophyta) 总被引:2,自引:0,他引:2
The freshwater green microalga Parietochloris incisa is the richest known plant source of the polyunsaturated fatty acid (PUFA), arachidonic acid (20:4omega6, AA). While many microalgae accumulate triacylglycerols (TAG) in the stationary phase or under certain stress conditions, these TAG are generally made of saturated and monounsaturated fatty acids. In contrast, most cellular AA of P. incisa resides in TAG. Using various inhibitors, we have attempted to find out if the induction of the biosynthesis of AA and the accumulation of TAG are codependent. Salicylhydroxamic acid (SHAM) affected a growth reduction that was accompanied with an increase in the content of TAG from 3.0 to 6.2% of dry weight. The proportion of 18:1 increased sharply in all lipids while that of 18:2 and its down stream products, 18:3omega6, 20:3omega6 and AA, decreased, indicating an inhibition of the Delta12 desaturation of 18:1. Treatment with the herbicide SAN 9785 significantly reduced the proportion of TAG. However, the proportion of AA in TAG, as well as in the polar lipids, increased. These findings indicate that while there is a preference for AA as a building block of TAG, the latter can be produced using other fatty acids, when the production of AA is inhibited. On the other hand, inhibiting TAG construction did not affect the production of AA. In order to elucidate the possible role of AA in TAG we have labeled exponential cultures of P. incisa kept at 25 degrees C with [1-14C]arachidonic acid and cultivated the cultures for another 12 h at 25, 12 or 4 degrees C. At the lower temperatures, labeled AA was transferred from TAG to polar lipids, indicating that TAG of P. incisa may have a role as a depot of AA that can be incorporated into the membranes, enabling the organism to quickly respond to low temperature-induced stress. 相似文献
12.
Termites from the genus Odontotermes are known to contain numerous species complexes that are difficult to tell apart morphologically or with mitochondrial DNA sequences. We developed markers for one such cryptic species complex, that is, Odontotermes srinakarinensis sp. nov. from Maxwell Hill Forest Reserve (Perak, Malaysia), and characterised them using a sample of 41 termite workers from three voucher samples from the same area. We then genotyped 150 termite individuals from 23 voucher samples/colonies of this species complex from several sites in Peninsular Malaysia. We analysed their population by constructing dendograms from the proportion of shared-alleles between individuals and genetic distances between colonies; additionally, we examined the Bayesian clustering pattern of their genotype data. All methods of analysis indicated that there were two distinct clusters within our data set. After the morphologies of specimens from each cluster were reexamined, we were able to separate the two species morphologically and found that a single diagnostic character found on the mandibles of its soldiers could be used to separate the two species quite accurately. The additional species in the clade was identified as Odontotermes denticulatus after it was matched to type specimens at the NHM London and Cambridge Museum of Zoology. 相似文献
13.
Carlos A.P. Andrade Iolanda P.G. Brazão Marilyn P. Ferreira Maria T. Dinis 《Journal of experimental marine biology and ecology》2011,407(2):377-381
The feeding performance and behavior at the onset of exogenous feeding, 3 to 4 days after hatching (DAH), were studied in red porgy Pagrus pagrus larvae. Similar feeding efficiency and intensity were achieved for two feeding treatments (live or freeze-dried rotifers) suggesting that prey movement is not decisive for their detection and capture and demonstrating that at first feeding red porgy larvae can ingest inert food. Larvae feeding performance was not affected by a diet shift between treatments. Based on maximum rotifers consumption and gut evacuation time at 18 °C, the daily ration was estimated as 14.035 μg, considering 14 h of feeding and a 25% egg:female rotifer ratio. Larval swimming activity measured by video recording showed a close association with gut fullness and similar swimming patterns for 3 and 4 DAH larvae. However, 20.3% larger mouth gape and 54.6% higher swimming speed of the older larvae should provide a better feeding performance and more energy needed for growth. 相似文献
14.
Darius J.R. Lane Dong-Hun Bae Aritee R. Siafakas Yohan Suryo Rahmanto Lina Al-Akra Patric J. Jansson Robert A. Casero Des R. Richardson 《生物化学与生物物理学报:疾病的分子基础》2018,1864(9):2793-2813
Many biological processes result from the coupling of metabolic pathways. Considering this, proliferation depends on adequate iron and polyamines, and although iron-depletion impairs proliferation, the metabolic link between iron and polyamine metabolism has never been thoroughly investigated. This is important to decipher, as many disease states demonstrate co-dysregulation of iron and polyamine metabolism. Herein, for the first time, we demonstrate that cellular iron levels robustly regulate 13 polyamine pathway proteins. Seven of these were regulated in a conserved manner by iron-depletion across different cell-types, with four proteins being down-regulated (i.e., acireductone dioxygenase 1 [ADI1], methionine adenosyltransferase 2α [MAT2α], Antizyme and polyamine oxidase [PAOX]) and three proteins being up-regulated (i.e., S-adenosyl methionine decarboxylase [AMD1], Antizyme inhibitor 1 [AZIN1] and spermidine/spermine-N1-acetyltransferase 1 [SAT1]). Depletion of iron also markedly decreased polyamine pools (i.e., spermidine and/or spermine, but not putrescine). Accordingly, iron-depletion also decreased S-adenosylmethionine that is essential for spermidine/spermine biosynthesis. Iron-depletion additionally reduced 3H-spermidine uptake in direct agreement with the lowered levels of the polyamine importer, SLC22A16. Regarding mechanism, the “reprogramming” of polyamine metabolism by iron-depletion is consistent with the down-regulation of ADI1 and MAT2α, and the up-regulation of SAT1. Moreover, changes in ADI1 (biosynthetic) and SAT1 (catabolic) partially depended on the iron-regulated changes in c-Myc and/or p53. The ability of iron chelators to inhibit proliferation was rescuable by putrescine and spermidine, and under some conditions by spermine. Collectively, iron and polyamine metabolism are intimately coupled, which has significant ramifications for understanding the integrated role of iron and polyamine metabolism in proliferation. 相似文献