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131.
Baweja RB Zaman MS Mattoo AR Sharma K Tripathi V Aggarwal A Dubey GP Kurupati RK Ganguli M Chaudhury NK Sen S Das TK Gade WN Singh Y 《Archives of microbiology》2008,189(1):71-79
Bacillus anthracis makes highly stable, heat-resistant spores which remain viable for decades. Effect of various stress conditions on sporulation
in B. anthracis was studied in nutrient-deprived and sporulation medium adjusted to various pH and temperatures. The results revealed that
sporulation efficiency was dependent on conditions prevailing during sporulation. Sporulation occurred earlier in culture
sporulating at alkaline pH or in PBS than control. Spores formed in PBS were highly sensitive towards spore denaturants whereas,
those formed at 45°C were highly resistant. The decimal reduction time (D-10 time) of the spores formed at 45°C by wet heat,
2 M HCl, 2 M NaOH and 2 M H2O2 was higher than the respective D-10 time for the spores formed in PBS. The dipicolinic acid (DPA) content and germination
efficiency was highest in spores formed at 45°C. Since DPA is related to spore sensitivity towards heat and chemicals, the
increased DPA content of spores prepared at 45°C may be responsible for increased resistance to wet heat and other denaturants.
The size of spores formed at 45°C was smallest amongst all. The study reveals that temperature, pH and nutrient availability
during sporulation affect properties of B. anthracis spores. 相似文献
132.
Muhammad Saleem Sara Musaddiq Naheed Riaz Momina Zubair Muhammad Ashraf Rumana Nasar Abdul Jabbar 《Steroids》2013,78(11):1098-1102
Four new ecdysteroids (1–4), along with three known steroids, β-ecdysone (5), 5-β-2-deoxyintegristerone A (6) and 24-epi-makisterone A (7) (Fig. 1), were isolated from the methanolic extract of the flowers of Aerva javanica by using normal and reverse phase chromatography. The structures of the new compounds (1–4) were determined due to 1D (1H and 13C), 2D NMR (HSQC, HMBC, COSY, NOESY) techniques and high resolution mass spectrometry (HREIMS). The known compounds (5–7) were characterized based on the 1D NMR spectroscopy and mass spectrometry and by comparison with the literature values. All isolates were evaluated for their inhibitory activities against enzymes acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase (LOX). 相似文献
133.
Shahzab Riaz Joel B. Johnson Munir Ahmad Gary P. Fitt Mani Naiker 《Journal of Applied Entomology》2021,145(6):467-498
Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is one of the most damaging insect pests globally, causing estimated global economic losses of over 3 billion US dollars annually. Crops most affected include cotton, tomato, soybean, grain crops such as corn and sorghum, chickpea and other pulses. Adults of this species possess strong migratory abilities (>2000 km), high fecundity and rapid reproductive rates; completing 4–6 generations per year in most cropping regions. Furthermore, the larvae are polyphagous, with a wide and diverse host range and possess the ability to enter diapause in order to survive adverse climatic conditions. At present, it is distributed across most of Oceania, Asia, Africa and southern Europe and has recently spread to South America. Various control measures have been trialled or proposed for the treatment of this pest, including synthetic insecticides, phytopesticides, microbial pesticides, macro-biocontrol agents (both parasitoids and predators) and the development of genetically modified crops (e.g. Bt cotton). Successful control necessitates the use of an integrated pest management (IPM) approach, wherein biological, chemical and physical control measures are combined for the greatest control efficacy. 相似文献
134.
Abdulrahman Nabeel Jaballah Maiy Poomakkoth Noufira Riaz Sadaf Abdelaziz Somaia Issa Aya Mraiche Fatima 《Molecular and cellular biochemistry》2016,420(1-2):21-28
135.
Abdul Wadood Muhammad Riaz Syed Babar Jamal Masaud Shah 《Molecular biology reports》2014,41(1):337-345
HCV infection in more than 200 million individuals worldwide is a principal health problem. Prior to the development of HCV protease inhibitor combination therapy, HCV infected patients were treated with pegylated interferon-α and ribavirin. The adverse side effects associated with this type of treatment may lead to the discontinuation of treatment in certain number of patients. Currently, the inhibitors of NS3/4A Protease were found promising candidates for the treatment of HCV infection. There are several inhibitors of HCV NS3/4A protease that are passing through clinical improvement showing good potency against HCV infections in a number of patients. To further recognize binding interactions and activity trend, the molecular docking studies were performed on a number of HCV NS3/4A protease ketoamide inhibitors via MOE docking protocol. The docking analysis resulted in the detection of important ligand interactions with respect to binding site of target proteinand produced good correlation coefficient (r2 = 0.690) between docking score and biological activities. These molecular docking results should, in our view, contribute for further optimization of ketoamide derivatives as NS3/4A protease inhibitors. 相似文献
136.
137.
Syed Muddassar Hussain Gilani Zubia Rashid Saddia Galani Sahar Ilyas Shagufta Sahar Khalid Al-Ghanim Sitwat Zehra Abid Azhar F. Al-Misned Z. Ahmed N. Al-Mulham S. Mahboob 《Saudi Journal of Biological Sciences》2021,28(6):3438-3447
In an epoch of escalating number of antibiotic-resistance bacteria, there is a dire need to develop efficient and novel feeding strategies for animal nutrition as alternatives to antibiotics. Here, implicating nutrigenomic approach, phytobiotics and organic acids were used to evaluate ghrelin gene expression levels, gut microflora composition, performance parameters and intestinal histomorphological changes in broiler chickens. One-day-old chicks (n = 315) were reared for 42 days and distributed randomly into five experimental groups; each with three replicates (21 birds per replicate). Experimental groups were control: basal diet only, antimicrobial growth promoter: 40 g/metric ton of basal diet (virginiamycin), organic acids: 4 kg/metric ton of basal diet, phytobiotics: 3 kg/metric ton of basal diet, combination: 7 kg/metric ton of basal diet (organic acids 4 kg and phytobiotics 3 kg metric ton of feed). Growth performance, histological and ghrelin gene expression analysis were executed on 21 and 42 days while, quantitative bacterial analysis of cecum and ileum was performed on day 42. Increased feed intake and body weight (p < 0.05) were noticed in phytobiotics group. Addition of phytobiotics significantly improved (p < 0.05) villus height and ratio of villus height/crypt depth in ileum, jejunum, and duodenum and down-regulated ghrelin gene expression levels. Total coliform and Escherichia coli in cecal and ileal digesta were decreased significantly (p < 0.05) in organic acids group. Correlation analysis revealed Lactobacillus spp. were positively correlated to villus height/crypt depth ration in duodenum. The findings indicated the importance of gene-nutrient-microbiota interactions based on nutrigenomics approach. Hence, phytobiotics and organic acids might be suitable alternatives to antibiotics for improved performance and immunity, along with healthier meat production in poultry. 相似文献
138.
Sidra Younis Farah Deeba Rida Fatima Saeed Ramzi A. Mothana Riaz Ullah Muhammad Faheem Qamar Javed Miroslav Blumenberg 《Saudi Journal of Biological Sciences》2022,29(3):1717-1729
Skin is the first line of defense against the physical, chemical and the biological environment. It is an ideal organ for studying molecular responses to biological infections through a variety of skin cells that specialize in immune responses. Comparative analysis of skin response to pathogenic, non-pathogenic, and commensal bacteria would help in the identification of disease specific pathways for drug targets. In this study, we investigated human breast reduction skin responses to Cutibacterium acnes (C. acnes), Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and TLR1/2 agonist using Affymetrix microarray chips. The Pam3CSK4 solution and bacterial cultures were prepared and inoculated in steel rings, that were placed on the acetone treated epidermis in a petri dish. After 24 h incubation, 8 mm punch biopsies were taken from the center of the ring, and RNA was extracted. The genome-wide expression was then analyzed using Affymetrix HG-133A gene chip microarray. We found that the C. acnes and S. aureus boosted the production of extracellular matrix components and attenuated the expression of differentiation markers. The above responses were mediated through the TLR2 pathway. Skin also responded to S. aureus and C. acnes by inducing the genes of the cell cycle machinery; this response was not TLR2-dependent. S. aureus induced, whereas C. acnes suppressed the genes associated with apoptosis; this was also not TLR2-dependent. Moreover, S. epidermis apparently did not lead to changes in gene expression. We conclude that the breast reduction skin is a very useful model to study the global gene expression in response to bacterial treatments. 相似文献
139.
140.
Muhammad Zafar-ul-Hye Misbah Batool Zahra Subhan Danish Mazhar Abbas Abdur Rehim Muhammad Naeem Akbar Ayesha Iftikhar Mehreen Gul Ifat Nazir Maria Abid Muhammad Tahzeeb-ul-Hassan Maria Murtaza 《Phyton》2020,89(2):405-413
Rhizosphere bacteria that colonize plant roots and confer beneficialeffects are referred as plant growth promoting rhizobacteria (PGPR). Among allPGPR, some rhizobacteria have an ability to produce ACC deaminase enzyme.This enzyme catalyzes stress ACC into a-ketobutyrate and ammonia instead ofletting it to be converted to ethylene. Ethylene level rises in plants under stressconditions i.e., drought, salinity, poor soil fertility etc. As poor soil fertility is abig hurdle to achieve the optimum yield of crops, inoculation of ACC deaminasePGPR can overcome this problem to some extent. The aim of the current studywas to examine the influence of multi-strain and single-strain inoculation of different ACC deaminase producing PGPR on wheat growth and yield. There werethree PGPR strains, Enterobacter cloacae, Serratia ficaria and Burkholderia phytofirmans which were used as consortia and single-strain inoculations. The resultsshowed that inoculation of E. cloacae + S. ficaria + B. phytofirmans significantlyincreased plant height (63%), spike length (61%), number of spikelets spike-1(61%), number of grains spike-1 (131%), 1000 grains weight (33%), grains yield(71%), straw yield (71%) and biological yield (68%) of wheat as compared tocontrol. A significant improvement in N (37 and 200%), P (46 and 166%) andK (39 and 61%) of seeds and shoot respectively, validated the efficacious andmore effective role of multi-strain (E. cloacae + S. ficaria + B. phytofirmans)inoculation over control. It is obviously concluded that multi-strain ACC deaminase producing PGPR inoculation is a better approach as compared to singlestrain inoculation for the improvement in growth and yield of wheat. 相似文献