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991.
Dinesh Singh Garima Chaudhary D. K. Yadav 《Archives Of Phytopathology And Plant Protection》2018,51(5-6):267-276
Genetic diversity of 13 isolates of Ralstonia solanacearum causing bacterial wilt in hot pepper and bell pepper (Capsicum annuum L.) from 6 states of India was assessed. All isolates of R. solanacearum belonged to biovar 3, race 1 and phylotype I. These isolates consisted of 4 distinct DNA types at 75% similarity coefficient using ERIC, BOX and REP-PCRs techniques. Multilocus sequence analysis of hrpB, fliC and egl genes of 6 isolates of R. solanacearum along with 2 out group bacteria was done and they showed high level of variability within these three regions of the genome involving in pathogenicity. 相似文献
992.
Vijay Rayamajhi Dipesh Dhakal Amit Kumar Chaudhary Jae Kyung Sohng 《World journal of microbiology & biotechnology》2018,34(6):77
Azasugars, such as 1-deoxynojirymicin (1-DNJ), are associated with diverse pharmaceutical applications, such as antidiabetic, anti-obesity, anti-HIV, and antitumor properties. Different azasugars have been isolated from diverse microbial and plant sources though complicated purification steps, or generated by costly chemical synthesis processes. But the biosynthesis of such potent molecules using Escherichia coli as a heterologous host provides a broader opportunity to access these molecules, particularly by utilizing synthetic biological, metabolic engineering, and process optimization approaches. This work used an integrated approach of synthetic biology, enzyme engineering, and pathway optimization for rational metabolic engineering, leading to the improved production of 1-DNJ. The production of 1-DNJ in recombinant E. coli culture broth was confirmed by enzymatic assays and mass spectrometric analysis. Specifically, the pathway engineering for its key precursor, fructose-6-phosphate, along with optimized media condition, results in the highest production levels. When combined, 1-DNJ production was extended to ~?273 mg/L, which is the highest titer of production of 1-DNJ reported using E. coli. 相似文献
993.
Jaywant M. Nawale Sandip N. Patil Digvijay D. Nalawade Nikhil A. Borikar Bhushan S. Sonawane Ajay S. Chaurasia 《Indian pacing and electrophysiology journal》2018,18(4):148-149
Implantation of temporary pacemaker lead is commonly performed procedure and is usually safe, but can sometimes develop rare and serious complication like intracardiac lead knotting which may require challenging retrieval techniques. We report a case of successful percutaneous retrieval of unusually knotted right internal jugular venous temporary pacing lead via left femoral transvenous approach using snare over a long sheath after cutting the electrode proximally and thus avoiding any surgical intervention. 相似文献
994.
Regulated proteolysis is required in all organisms for the removal of misfolded or degradation-tagged protein substrates in cellular quality control pathways. The molecular machines that catalyze this process are known as ATP-dependent proteases with examples that include ClpAP and ClpCP. Clp/Hsp100 subunits form ring-structures that couple the energy of ATP binding and hydrolysis to protein unfolding and subsequent translocation of denatured protein into the compartmentalized ClpP protease for degradation. Copies of the clpA, clpC, clpE, clpK, and clpL genes are present in all characterized bacteria and their gene products are highly conserved in structure and function. However, the evolutionary relationship between these proteins remains unclear. Here we report a comprehensive phylogenetic analysis that suggests divergent evolution yielded ClpA from an ancestral ClpC protein and that ClpE/ClpL represent intermediates between ClpA/ClpC. This analysis also identifies a group of proteobacterial ClpC proteins that are likely not functional in regulated proteolysis. Our results strongly suggest that bacterial ClpC proteins should not be assumed to all function identically due to the structural differences identified here. 相似文献
995.
A. Sivakumar H. M. Yathish Chinmoy Mishra Rajendra Prasad Modi Rajni Chaudhary 《Animal biotechnology》2018,29(1):34-40
122 randomly selected Vrindavani cattle were studied to detect polymorphism in four fragments of the CatSper2 gene that were comprised of exon 2, 4, 5, and 6 with flanking regions. Using PCR-SSCP and sequencing analysis, three SNPs (T157C, C273A, and A274C) in the first fragment, one SNP (C30G) in the second fragment, and two SNPs (T86G and T292C) in the fourth fragment were identified. The third fragment did not reveal any polymorphism. The SNPs were used for construction of haplotypes and three haplotypes were found. The least square analysis of variance revealed a significant (P?0.01) effect of haplotype on all three motility parameters. The haplotype II and III were nonsignificantly different from each other while being significantly (P?0.01) different from haplotype I. The nonsignificant difference of haplotype II with III can lead to a hypothesis that T>G or C>T SNPs may not play a role in sperm motility. However, when the comparison was made between haplotype I and II, it can be inferred that C>T SNP may have a role in sperm motility, as haplotype II has better motility parameters. Expression profiling of Catper2 gene revealed nonsignificant down regulation of CatSper2 gene in poor motility sperm compared to good motility sperm. 相似文献
996.
Background
The present study elucidates the protective potential of bromelain against dichlorvos intoxication in mice brains. Dichlorvos induces the oxidative stress by disproportionating the balance between free radicals generation and their scavenging in neurons which leads to neuronal degeneration.Methods
In this study, mice were divided into four groups-group I (control), group II (dichlorvos treated), group III (bromelain treated) and group IV (exposed to both bromelain and dichlorvos both).Results
Dichlorvos treatment increased the levels of thiobarbituric acid reactive substances (TBARS) and protein carbonyl content (PCC) which indicate the increased oxidative stress. Meanwhile, brain endogenous antioxidants and cholinesterases level was decreased after dichlorvos exposure. Levels of TBARS and PCC decreased whereas cholinesterases level was recorded to be elevated after bromelain exposure.Conclusion
Bromelain offered neuroprotection by decreasing oxidative stress and augmenting cholinesterases in mice brains. This study highlights the invulnerability of bromelain against oxidative and cholinergic deficits in mice brains.997.
Prakash Kishore Hazam Gaurav Jerath Nitin Chaudhary Vibin Ramakrishnan 《International journal of peptide research and therapeutics》2018,24(2):299-307
Biocompatibility, low toxicity and high selectivity towards bacterial cells has been the hallmark of peptide-based antibiotics. The innate immune system has been employing such molecular systems against invading pathogens as a successful defense strategy. In this study, we attempt to develop topologically constrained antimicrobial peptides with syndiotactic stereochemical arrangement, by incorporating L and D amino acids successively in its amino acid sequence. Acetylated versions of the designed peptides were also examined for its influence on bactericidal potency, against Gram-positive and Gram-negative bacteria. Syndiotactic stereochemical arrangement of the polypeptide main chain mimics stereochemistry of Gramicidin, a naturally occurring antimicrobial peptides. Gramicidin is a class of penta-deca-peptides isolated from soil bacteria Bacillus brevis, but their utility as antibiotic was limited to topical use due to high levels of hemotoxicity. Activity profiles of the four de novo designed peptide variants show higher specificity towards Gram-positive bacteria than Gram-negative variants, matching earlier reports on the therapeutic potential of gramicidin as a broad spectrum antibiotic. Significantly, our hemolytic assay confirms very low (<1%) levels of toxicity for the designed peptides unlike gramicidin. Earlier reports confirm that incorporation of D amino acids effectively negates the possibility of proteolytic degradation, thus pointing to the potential utility of de novo designed peptides with diversified stereochemistry as a promising new approach in the generation of novel antibiotic peptides. 相似文献
998.
Tandem tyrosine phosphosites in the Enteropathogenic Escherichia coli chaperone CesT are required for differential type III effector translocation and virulence
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Cameron S. Runte Umang Jain Landon J. Getz Sabrina Secord Asaomi Kuwae Akio Abe Jason J. LeBlanc Andrew W. Stadnyk James B. Kaper Anne‐Marie Hansen Nikhil A. Thomas 《Molecular microbiology》2018,108(5):536-550
Enteropathogenic Escherichia coli (EPEC) use a type 3 secretion system (T3SS) for injection of effectors into host cells and intestinal colonization. Here, we demonstrate that the multicargo chaperone CesT has two strictly conserved tyrosine phosphosites, Y152 and Y153 that regulate differential effector secretion in EPEC. Conservative substitution of both tyrosine residues to phenylalanine strongly attenuated EPEC type 3 effector injection into host cells, and limited Tir effector mediated intimate adherence during infection. EPEC expressing a CesT Y152F variant were deficient for NleA effector expression and exhibited significantly reduced translocation of NleA into host cells during infection. Other effectors were observed to be dependent on CesT Y152 for maximal translocation efficiency. Unexpectedly, EPEC expressing a CesT Y153F variant exhibited significantly enhanced effector translocation of many CesT‐interacting effectors, further implicating phosphosites Y152 and Y153 in CesT functionality. A mouse infection model of intestinal disease using Citrobacter rodentium revealed that CesT tyrosine substitution variants displayed delayed colonization and were more rapidly cleared from the intestine. These data demonstrate genetically separable functions for tandem tyrosine phosphosites within CesT. Therefore, CesT via its C‐terminal tyrosine phosphosites, has relevant roles beyond typical type III secretion chaperones that interact and stabilize effector proteins. 相似文献
999.
Circadian rhythms are perhaps among the genetically best characterized behaviours.
Several mutations with drastic effects on circadian processes have been identified and
models developed to explain how clock genes and their products generate self-sustained
oscillations. Although natural variations in circadian phenotypes have been studied
extensively, the genetic basis of such adaptive variations remains largely unknown. Here
we report the results of a preliminary genetic analysis of adaptive divergence of
circadian phenotypes in populations of fruit flies Drosophila melanogaster. Two
sets of populations, ‘early'' and ‘late'', were created in a
long-term laboratory selection for morning and evening emergence, with four independent
replicates each. Over the course of ∼55 generations, the early flies evolved increased
morning emergence and a shorter circadian period, whereas late flies evolved increased
evening emergence and longer period. To examine the genetic basis of circadian phenotypes,
we set up crosses between early and late flies, and monitored emergence and
activity/rest rhythms in the F1, backcrossed and F2 progeny. Our analysis suggests
that the genetic basis of divergent circadian phenotypes in early and late stocks is
primarily autosomal. Line-cross analysis revealed that additive and non-additive genetic
effects contribute to the divergence of circadian phenotypes in early and late flies. 相似文献
1000.
Benoit Boivin Fauzia Chaudhary Bryan C. Dickinson Aftabul Haque Stephanie C. Pero Christopher J. Chang Nicholas K. Tonks 《The Journal of biological chemistry》2013,288(52):36926-36935
We investigated the role of protein-tyrosine phosphatase α (PTPα) in regulating signaling by the ErbB2 oncoprotein in mammary epithelial cells. Using this model, we demonstrated that activation of ErbB2 led to the transient inactivation of PTPα, suggesting that attenuation of PTPα activity may contribute to enhanced ErbB2 signaling. Furthermore, RNAi-induced suppression of PTPα led to increased cell migration in an ErbB2-dependent manner. The ability of ErbB2 to increase cell motility in the absence of PTPα was characterized by prolonged interaction of GRB7 with ErbB2 and increased association of ErbB2 with a β1-integrin-rich complex, which depended on GRB7-SH2 domain interactions. Finally, suppression of PTPα resulted in increased phosphorylation of focal adhesion kinase on Tyr-407, which induced the recruitment of vinculin and the formation of a novel focal adhesion kinase complex in response to ErbB2 activation in mammary epithelial cells. Collectively, these results reveal a new role for PTPα in the regulation of motility of mammary epithelial cells in response to ErbB2 activation. 相似文献