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排序方式: 共有502条查询结果,搜索用时 15 毫秒
481.
Chin Hong Lee Nathaniel P. Hawker Jonathan R. Peters Thierry G. A. Lonhienne Nial R. Gursanscky Louisa Matthew Christopher A. Brosnan Christopher W. G. Mann Laurence Cromer Christelle Taochy Quy A. Ngo Venkatesan Sundaresan Peer M. Schenk Bostjan Kobe Filipe Borges Raphael Mercier John L. Bowman Bernard J. Carroll 《PLoS genetics》2021,17(5)
The DEFECTIVE EMBRYO AND MERISTEMS 1 (DEM1) gene encodes a protein of unknown biochemical function required for meristem formation and seedling development in tomato, but it was unclear whether DEM1’s primary role was in cell division or alternatively, in defining the identity of meristematic cells. Genome sequence analysis indicates that flowering plants possess at least two DEM genes. Arabidopsis has two DEM genes, DEM1 and DEM2, which we show are expressed in developing embryos and meristems in a punctate pattern that is typical of genes involved in cell division. Homozygous dem1 dem2 double mutants were not recovered, and plants carrying a single functional DEM1 allele and no functional copies of DEM2, i.e. DEM1/dem1 dem2/dem2 plants, exhibit normal development through to the time of flowering but during male reproductive development, chromosomes fail to align on the metaphase plate at meiosis II and result in abnormal numbers of daughter cells following meiosis. Additionally, these plants show defects in both pollen and embryo sac development, and produce defective male and female gametes. In contrast, dem1/dem1 DEM2/dem2 plants showed normal levels of fertility, indicating that DEM2 plays a more important role than DEM1 in gamete viability. The increased importance of DEM2 in gamete viability correlated with higher mRNA levels of DEM2 compared to DEM1 in most tissues examined and particularly in the vegetative shoot apex, developing siliques, pollen and sperm. We also demonstrate that gamete viability depends not only on the number of functional DEM alleles inherited following meiosis, but also on the number of functional DEM alleles in the parent plant that undergoes meiosis. Furthermore, DEM1 interacts with RAS-RELATED NUCLEAR PROTEIN 1 (RAN1) in yeast two-hybrid and pull-down binding assays, and we show that fluorescent proteins fused to DEM1 and RAN1 co-localize transiently during male meiosis and pollen development. In eukaryotes, RAN is a highly conserved GTPase that plays key roles in cell cycle progression, spindle assembly during cell division, reformation of the nuclear envelope following cell division, and nucleocytoplasmic transport. Our results demonstrate that DEM proteins play an essential role in cell division in plants, most likely through an interaction with RAN1. 相似文献
482.
483.
Dharman Kalaimurugan Palaniappan Sivasankar Kaliannan Durairaj Manokaran Lakshmanamoorthy Sulaiman Ali Alharbi Sulaiman A. Al Yousef Arunachalam Chinnathambi Srinivasan Venkatesan 《Saudi Journal of Biological Sciences》2021,28(1):833
The mass organic compound 4-nitrophenol with low molecular is involved in many chemicals processes and most common organic pollutants. 4-Nitrophenol (4-NP) existing in soils and water bodies, thereby causing severe environmental impact and health risk. Even low concentrations are harmful to health and potential mutagenic and carcinogenic. Though the existing methods of biodegradation though effective, their popularity is hindered due to high cost. Hence, in the present study a less expensive method involving the use of Pseudomonas sp. with gum arabic (PAA) was tested. The biodegradation of 4-NP was thoroughly investigated by progressive characterization methods. The promising Pseudomonas sp. YPS 3 was identified with biochemical and molecular identification process. The average particle sizes of stable crystalline PAA was 8–20 nm. The experiments were conducted with optimized parameters viz., pH (7.0), concentration (30 ppm), temperature (37 °C) and time (6 h). The study was tested as adsorbent particle size on 4-NP concurrent adsorption-biodegradation. In addition, these Pseudomonas sp. YPS3 and its PAA are used as an eco-friendly for removal of toxic organic 4-NP pollutant from the ecosystems. 相似文献
484.
Alagesan Paari Kanmani Paulraj Satishkumar Ramraj Yuvaraj Neelkandan Pattukumar Vellaiyan Ponni Siva Arul Venkatesan 《Probiotics and antimicrobial proteins》2011,3(2):103-111
The influence of Streptococcus phocae PI80 on the shelf life of Sardinella longiceps and Penaeus monodon was investigated by measurement of microbial and chemical analysis after appraising the safety of the protective probiotic culture in wistar rat’s model. The results of this safety assessment indicate that oral administration of protective culture does not demonstrate any toxicological effects. Consumption of this LAB strain had no adverse effects on animal’s general health status, hematology, blood biochemistry, histology parameters, or on the incidence of bacterial translocation. The effect of Streptococcus phocae is very evident with the reduction of Listeria monocytogenes, Vibrio parahemolyticus, and coliforms. During storage, a marked decline in total volatile base and peroxide value was observed in protective culture-treated samples than the control. This strain looks promising as a protective culture for the preservation of fish products. 相似文献
485.
Hee-Seok Jeong Jayachandran Venkatesan Se-Kwon Kim 《Biotechnology and Bioprocess Engineering》2013,18(6):1185-1191
In the present study, we isolated collagen from Thunnus obesus bone, which was physiochemically characterized. Two different kinds of methods were used to isolate the collagen; they are the Acid Soluble Collagen (ASC) and Acid Soluble Enzyme Collagen (ASEC) methods. The isolated collagen was characterized with Fourier Transform Infrared Spectroscopy (FT-IR), SDS-polyacrylamide gel electrophoresis (SDS-PAGE), Optical Microscopy (OM) and Scanning Electron Microscopy (SEM). FT-IR results revealed the presence of collagen. SEM and OM results depicted that collagen was in the form of fiber sponge-like scaffolds. The isolated collagen scaffold was checked with pre-osteoblast (MC3T3-E1) cell line for biocompatibility. The in vitro results revealed that the collagen scaffolds were highly biocompatible and nontoxic in nature. Herewith, we are suggesting that marine fish-derived collagen will be an excellent material for leather, film industry, pharmaceutical, cosmetics, biomedical and food applications. 相似文献
486.
Males, females and egg carrying males of water bug D. indicus were collected at different sites from Chetpet pond, Madras, India. The bugs showed differences in their predatory efficiencies in relation to density, size and type of prey. The bug showed a typical predatory response in relation to hunger level. 相似文献
487.
Ranganathan Budhi Venkatesan 《International journal of phytoremediation》2019,21(8):816-820
AbstractThe present study investigates the suitability of growing Dicloster acuatus MH013435 and Kalenjinia gelatinosa MH012185 in Garcinia cambogia washwater for biomass production and nutrient removal. In recent years, the wastewater effluent treatment with microalgae is gaining importance since it serves multiple purposes including CO2 sequestration, production of biofuel feedstock and value-added biochemicals in addition to wastewater treatment. Contaminated washwater is generated at a significant quantity during extraction of hydroxycitric acid from G. cambogia and it represents a serious environmental concern when discharged without proper processing. However, this G. cambogia washwater can be used as a low-cost source of nutrients for microalgal growth. The two microalgal species D. acuatus MH013435 and K. gelatinosa MH012185 demonstrated robust growth in washwater and achieved maximum biomass concentration of 0.68 and 0.63?g/L dry weight. The nitrate was removed to an extent of 98.5 and 99.6% whereas chloride removal was 72 and 80.5%, sulfate concentration got reduced by 98 and 98.7% and phosphate got reduced to 95 and 92% for D. acuatus MH013435 and K. gelatinosa MH012185, respectively. The results indicate the suitability of D. acuatus MH013435 and K. gelatinosa MH012185 in treating G. cambogia washwater with efficient nutrient removal. 相似文献
488.
Lavanya Raja Srinivasadesikan Venkatesan Ming-Chang Lin Padmini Vediappen 《Luminescence》2023,38(3):224-231
An economical and green approach to the synthesis of naphthyl derivative for detection of l -carnitine (3-hydroxy-4-N-trimethyl-aminobutyrate) is practically important. We developed a naphthyl derivative as a probe showing ‘turn-on’ response towards l -carnitine selectively at pH 7.2 through ICT mechanism with a good limit of detection (LOD) of 0.126 μM. Using Job's plot for determining the binding stoichiometry, it was found that probe could form a more stable complex (1:1) with carnitine. The binding constant (K) between probe and carnitine was calculated as 8 × 107 M−1 using the Benesi–Hildebrand plot. The binding interaction of the probe with l -carnitine was confirmed by nuclear magnetic resonance titrations, Fourier-transform infrared spectroscopy, photo physical studies and density functional theory calculations. Meanwhile, the probe can be used to quantitatively detect carnitine in food samples. 相似文献
489.
Soumhya Venkatesan 《The journal of the Royal Anthropological Institute》2021,27(3):478-495
A wedding between two trees in a Tamil village reveals that a tree can be more than, while still remaining, a tree. It needs to be a tree because trees do certain things. It can be made more than a tree, however, through a logic of homological connections which temporarily create equivalences between trees and divinities. The wedding (kalyanam), a ubiquitous Tamil ritual form which pertains not only to marriage, creatively and subjunctively opens up new possibilities to change ‘it could be’ and ‘it should be’ to ‘let it be so’. The wedding of two trees seeks to materialize ideal situations and outcomes by mobilizing the aliveness of trees, a quality they share with humans and animals, without positing personhood, identity, or confusing categories. In making this argument, I question choices of comparators in anthropological analyses which posit a holistic ‘non-West’ against a dualistic ‘West’ and contrast a taken-for-granted ‘us’ with ‘our’ really rather different ‘others’. 相似文献
490.