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21.
Plant Molecular Biology - Role of Rubisco Activase in imparting thermotolerance to the photosynthetic apparatus under high temperature. Thus, to improve the grain filling, we need to fine tune... 相似文献
22.
Microbial plant interaction plays a major role in the sustainability of plants. The understanding of phytomicrobiome interactions enables the gene-editing tools for the construction of the microbial consortia. In this interaction, microbes share several common secondary metabolites and terpenoid metabolic pathways with their host plants that ensure a direct connection between the microbiome and associated plant metabolome. In this way, the CRISPR-mediated gene-editing tool provides an attractive approach to accomplish the creation of microbial consortia. On the other hand, the genetic manipulation of the host plant with the help of CRISPR-Cas9 can facilitate the characterization and identification of the genetic determinants. It leads to the enhancement of microbial capacity for more trait improvement. Many plant characteristics like phytovolatilization, phytoextraction, phytodesalination and phytodegradation are targeted by these approaches. Alternatively, chemical communications by PGPB are accomplished by the exchange of different signal molecules. For example, quorum-sensing is the way of the cell to cell communication in bacteria that lead to the detection of metabolites produced by pathogens during adverse conditions and also helpful in devising some tactics towards understanding plant immunity. Along with quorum-sensing, different volatile organic compounds and N-acyl homoserine lactones play a significant role in cell to cell communication by microbe to plant and among the plants respectively. Therefore, it is necessary to get details of all the significant approaches that are useful in exploring cell to cell communications. In this review, we have described gene-editing tools and the cell to cell communication process by quorum-sensing based signaling. These signaling processes via CRISPR- Cas9 mediated gene editing can improve the microbe-plant community in adverse climatic conditions. 相似文献
23.
Saghir Abbas Muhammad Tariq Javed Qasim Ali Muhammad Sohail Akram Kashif Tanwir Shafaqat Ali Hassan Javed Chaudhary Naeem Iqbal 《Physiology and Molecular Biology of Plants》2021,27(2):297
Cadmium (Cd) in soil–plant system can abridge plant growth by initiating alterations in root zones. Hydroponics and rhizoboxes are useful techniques to monitor plant responses against various natural and/or induced metal stresses. However, soil based studies are considered more appropriate in order to devise efficient food safety and remediation strategies. The present research evaluated the Cd-mediated variations in elemental dynamics of rhizospheric soil together with in planta ionomics and morpho-physio-biochemical traits of two differentially Cd responsive maize cultivars. Cd-sensitive (31P41) and Cd-tolerant (3062) cultivars were grown in pots filled with 0, 20, 40, 60 and 80 µg/kg CdCl2 supplemented soil. The results depicted that the maize cultivars significantly influenced the elemental dynamics of rhizosphere as well as in planta mineral accumulation under applied Cd stress. The uptake and translocation of N, P, K, Ca, Mg, Zn and Fe from rhizosphere and root cell sap was significantly higher in Cd stressed cv. 3062 as compared to cv. 31P41. In sensitive cultivar (31P41), Cd toxicity resulted in significantly prominent reduction of biomass, leaf area, chlorophyll, carotenoids, protein contents as well as catalase activity in comparison to tolerant one (3062). Analysis of tolerance indexes (TIs) validated that cv. 3062 exhibited advantageous growth and efficient Cd tolerance due to elevated proline, phenolics and activity of antioxidative machinery as compared to cv. 31P41. The cv. 3062 exhibited 54% and 37% less Cd bio-concentration (BCF) and translocation factors (TF), respectively in comparison to cv. 31P41 under highest Cd stress regime. Lower BCF and TF designated a higher Cd stabilization by tolerant cultivar (3062) in rhizospheric zone and its potential use in future remediation plans. 相似文献
24.
H. Panwar N. Rokana S. V. Aparna J. Kaur A. Singh J. Singh K.S. Singh V. Chaudhary A.K. Puniya 《Journal of applied microbiology》2021,130(4):1035-1061
The human gastrointestinal (GI) tract has been bestowed with the most difficult task of protecting the underlying biological compartments from the resident commensal flora and the potential pathogens in transit through the GI tract. It has a unique environment in which several defence tactics are at play while maintaining homeostasis and health. The GI tract shows myriad number of environmental extremes, which includes pH variations, anaerobic conditions, nutrient limitations, elevated osmolarity etc., which puts a check to colonization and growth of nonfriendly microbial strains. The GI tract acts as a highly selective barrier/platform for ingested food and is the primary playground for balance between the resident and uninvited organisms. This review focuses on antimicrobial defense mechanisms of different sections of human GI tract. In addition, the protective mechanisms used by microbes to combat the human GI defence systems are also discussed. The ability to survive this innate defence mechanism determines the capability of probiotic or pathogen strains to confer health benefits or induce clinical events respectively. 相似文献
25.
26.
Rinky Rajput Ved Vrat Verma Vishal Chaudhary Rani Gupta 《Extremophiles : life under extreme conditions》2013,17(1):29-41
??-Glutamyl transpeptidase of a thermo-acidophilic archaeon Picrophilus torridus was cloned and expressed using E. coli Rosetta-pET 51b(+) expression system. The enzyme was expressed at 37 °C/200 rpm with ??-GT production of 1.99 U/mg protein after 3 h of IPTG induction. It was improved nearby 10-fold corresponding to 18.92 U/mg protein in the presence of 2 % hexadecane. The enzyme was purified by Ni2+-NTA with a purification fold of 3.6 and recovery of 61 %. It was synthesized as a precursor heterodimeric protein of 47 kDa with two subunits of 30 kDa and 17 kDa, respectively, as revealed by SDS-PAGE and western blot. The enzyme possesses hydrolase activity with optima at pH 7.0 and 55 °C. It was thermostable with a t 1/2 of 1 h at 50 °C and 30 min at 60 °C, and retained 100 % activity at 45 °C even after 24 h. It was inhibited by azaserine and DON and PMSF. Pt??-GT shared 37 % sequence identity and 53 % homology with an extremophile ??-GT from Thermoplasma acidophilum. Functional residues identified by in silico approaches were further validated by site-directed mutagenesis where Tyr327 mutated by Asn327 introduced significant transpeptidase activity. 相似文献
27.
Preeti Gupta Yingfeng Zheng Tay Wan Ting Ecosse L. Lamoureux Ching-Yu Cheng Tien-Yin Wong 《PloS one》2013,8(10)
Objective
To determine the prevalence of cataract surgery and factors associated with post-surgical visual outcomes in migrant Indians living in Singapore.Research Design and Methods
We conducted a population-based study in 3,400 Indian immigrants residing in Singapore−the Singapore Indian Eye Study (SINDI). All participants underwent comprehensive medical eye examination and a standardized interview. Post-operative visual impairment (VI) was defined as best-corrected or presenting visual acuity (BCVA or PVA) of 20/60 or worse.Results
The age- and gender-standardized prevalence of cataract surgery was 9.7% (95% confidence interval [CI]: 8.9%, 10.7%) in Singapore resident Indians. Post-operative VI defined by BCVA occurred in 10.9% eyes (87/795). The main causes of post-operative VI were diabetic retinopathy (20.7%), posterior capsular opacification (18.4%), and age-related macular degeneration (12.6%). Undercorrected refractive error doubled the prevalence of post-operative VI when PVA was used.Conclusions
The rate of cataract surgery is about 10% in Indian residents in Singapore. Socioeconomic variables and migration had no significant impact on the prevalence of cataract surgery. Diabetic retinopathy was a major cause of post-operative VI in migrant Indians living in Singapore. Uncorrected postoperative refractive error remains an efficient way to improve vision. 相似文献28.
Vijayalakshmi Sridharan Preeti Tripathi Sunil Sharma Peter M. Corry Eduardo G. Moros Awantika Singh Cesar M. Compadre Martin Hauer-Jensen Marjan Boerma 《PloS one》2013,8(7)
Radiation-induced heart disease (RIHD) is a long-term side effect of radiotherapy of intrathoracic, chest wall and breast tumors when radiation fields encompass all or part of the heart. Previous studies have shown that pentoxifylline (PTX) in combination with α-tocopherol reduced manifestations of RIHD in rat models of local heart irradiation. The relative contribution of PTX and α-tocopherol to these beneficial effects are not known. This study examined the effects of PTX alone or in combination with tocotrienols, forms of vitamin E with potential potent radiation mitigation properties. Rats received localized X-irradiation of the heart with an image-guided irradiation technique. At 3 months after irradiation rats received oral treatment with vehicle, PTX, or PTX in combination with a tocotrienol-enriched formulation. At 6 months after irradiation, PTX-treated rats showed arrhythmia in 5 out of 14 animals. PTX alone or in combination with tocotrienols did not alter cardiac radiation fibrosis, left ventricular protein expression of the endothelial markers von Willebrand factor and neuregulin-1, or phosphorylation of the signal mediators Akt, Erk1/2, or PKCα. On the other hand, tocotrienols reduced cardiac numbers of mast cells and macrophages, but enhanced the expression of tissue factor. While this new rat model of localized heart irradiation does not support the use of PTX alone, the effects of tocotrienols on chronic manifestations of RIHD deserve further investigation. 相似文献
29.
Aadithya Arumugam Zhiping Weng Sarang S. Talwelkar Sandeep C. Chaudhary Levy Kopelovich Craig A. Elmets Farrukh Afaq Mohammad Athar 《PloS one》2013,8(11)
Non-melanoma skin cancer (NMSC) is the most common type of skin cancer in Caucasian populations. Its increasing incidence has been a major public health concern. Elevated expressions of ODC and COX-2 are associated with both murine and human NMSCs. Inhibition of these molecular targets singly employing their respective small molecule inhibitors showed limited success. Here, we show that combined blockade of ODC and COX-2 using their potent inhibitors, DFMO and diclofenac respectively abrogates growth of A431 epidermal xenograft tumors in nu/nu mice by more than 90%. The tumor growth inhibition was associated with a diminution in the proliferation and enhancement in apoptosis. The proliferation markers such as PCNA and cyclin D1 were reduced. TUNEL-positive apoptotic cells and cleaved caspase-3 were increased in the residual tumors. These agents also manifested direct target-unrelated effects. Reduced expression of phosphorylated MAPKAP-2, ERK, and Akt (ser473 & thr308) were noticed. The mechanism by which combined inhibition of ODC/COX attenuated tumor growth and invasion involved reduction in EMT. Akt activation by ODC+COX-2 over-expression was the key player in this regard as Akt inhibition manifested effects similar to those observed by the combined inhibition of ODC+COX-2 whereas forced over-expression of Akt resisted against DFMO+diclofenac treatment. These data suggest that ODC+COX-2 over-expression together leads to pathogenesis of aggressive and invasive cutaneous carcinomas by activating Akt signaling pathway, which through augmenting EMT contributes to tumor invasion. 相似文献
30.
<i>Aspergillus tubingensis</i> Causes Leaf Spot of Cotton (<i>Gossypium hirsutum</i> L.) in Pakistan
Maria Khizar Urooj Haroon Musrat Ali Samiah Arif Iftikhar Hussain Shah Hassan Javed Chaudhary Muhammad Farooq Hussain Munis 《Phyton》2020,89(1):103-109
Cotton (Gossypium hirsutum L.) is a key fiber crop of great commercial
importance. Numerous phytopathogens decimate crop production by causing
various diseases. During July-August 2018, leaf spot symptoms were recurrently
observed on cotton leaves in Rahim Yar Khan, Pakistan and adjacent areas. Infected
leaf samples were collected and plated on potato dextrose agar (PDA) media.
Causal agent of cotton leaf spot was isolated, characterized and identified as
Aspergillus tubingensis based on morphological and microscopic observations.
Conclusive identification of pathogen was done on the comparative molecular
analysis of CaM and β-tubulin gene sequences. BLAST analysis of both sequenced
genes showed 99% similarity with A. tubingensis. Koch’s postulates were followed
to confirm the pathogenicity of the isolated fungus. Healthy plants were inoculated
with fungus and similar disease symptoms were observed. Fungus was re-isolated
and identified to be identical to the inoculated fungus. To our knowledge, this is the
first report describing the involvement of A. tubingensis in causing leaf spot disease
of cotton in Pakistan and around the world. 相似文献