16 research outputs found

    Complete Genome Sequence of Erwinia amylovora Bacteriophage

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    The complete genome of an Erwinia amylovora bacteriophage, vB_EamM_Ea35-70 (Ea35-70), is 271,084 bp, encodes 318 putative proteins, and contains one tRNA. Comparative analysis with other Myoviridae genomes suggests that Ea35-70 is related to the Phikzlikevirus genus within the family Myoviridae, since 26% of Ea35-70 proteins share homology to proteins in Pseudomonas phage φKZ.This work was supported by a Growing Forward II grant from Agriculture and Agri-Food Canada and Brock University. Financial support for the graduate student was obtained from the Ministry of Higher Education and Scientific Research of Libya

    Phage-mediated biological control of Erwinia amylovora: The role of CRISPRs and exopolysaccharide

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    Fire blight, caused by bacterium Erwinia amylovora, is a very serious disease affecting apple, pear and other fruit plants. The development of phage-based biopesticides is currently in progress in our lab. Emergence of phage-resistant bacteria is a valid concern. Two attributes of the bacterial host that may contribute to the development of resistance were studied, the Clustered Regularly Interspaced Short Palindromic Repeats/ CRISPR-associated (CRISPR/Cas) system and exopolysaccharide (EPS) interaction with phages. The structure of E. amylovora CRISPR/Cas system was determined in 8 E. amylovora isolates from different geographical regions. Three CRISPR-array sets named CR1, CR2 and CR3 were detected in 4 isolates, and only 2 arrays were determined in the rest of the isolates. No significant similarity was found between spacers in any of these systems to phage DNA sequenced in this study or from GenBank. Also the Cas level of expression was not stimulated during phage infection. Introduction of extra copies of Cas genes to enhance expression did not result in phage resistance. Nevertheless, E. amylovora CRISPR/Cas system was found to be efficient in blocking the transformation of plasmids carrying protospacers matched spacers in CRR1 and CRR2. Among phages that have been sequenced in this study are ΦEa9-2 and ΦEa35-70. ΦEa9-2 (Podoviridae) genome is 75,568 bp, and found to be related to coliphage N4. ΦEa35-70 (Myoviridae) genome is 271,084 bp, and found to carry a potential EPS depolymerase gene. Activity of ΦEa35-70 EPS depolymerase was only detected when cloned and expressed in E. coli, but His-tagged purified protein did not exhibit any EPS-depolymerase activities. This study offers critical information for the design of novel and effective phage-based biopesticides for the control of E. amylovora. It provides a new knowledge on the molecular structure and function of CRISPR/Cas system and EPS-phage interaction

    Subclasses of analytic functions defined by new generalised derivative operator

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    A new generalised derivative operator 12,,,nmDbλλ is introduced. This operator generalised some well-known operators studied earlier. New subclasses of analytic functions in the open unit disc which are defined using generalised derivative operator are introduced. Inclusion theorems are investigated. Furthermore, generalised Bernardi-Libera-Livington integral operator is shown to be preserved for these classes

    On fekete-szegö problems for a subclass of analytic functions

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    The aim of this paper is to determine the Fekete-Szegö inequalities for a normalised analytic function f (z) defined on the open unit disc for which z(Dλ1,λ2 ,δ m,b f (z))′ / (Dλ1,λ2 ,δ m,b f (z)),δ ,m,b ∈N0 ,λ2 ≥ λ1 ≥ 0 lies in a region starlike with respect to 1 and it is symmetric with respect to the real axis by using the operator Dλ1,λ2 ,δ m,b f (z) given recently by the authors. As a special case of this result, Fekete-Szegö inequality for a class of functions defined by fractional derivatives is also obtained

    Intuitionistic fuzzy parameterised fuzzy soft set

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    In this paper, the definition of intuitionistic fuzzy parameterised fuzzy soft set (ifpfs-sets) is introduced with their properties. Two operations on ifpfs-set, namely union and intersection are introduced. Also, some examples for these operations are given. The definition of ifpfsaggregation operator which forms ifpfs-decision making method is introduce

    Construction of bovine adenovirus type 3 E1 and E3, substitution plasmids and the sequencing analysis of DNA pol and pTP /

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    The relative ease to concentrate and purify adenoviruses, their well characterized mid-sized genome, and the ability to delete non-essential regions from their genome to accommodate foreign gene, made adenoviruses a suitable candidate for the construction of vectors. The use of adenoviral vectors in gene therapy, vaccination, and as a general vector system for expressing foreign genes have been documented for some time. In this study, the objective was to rescue a BAV3 E1 or E3 recombinant vector carrying the kanamycin resistant gene, a dominant selectable marker with useful applications in studying vectored gene expression in mammalian cells. To accomplish the objective of this study, more information about BAV3 DNA sequences was required in order to make the manipulation of the virus genome accessible. Therefore, sequencing of the BAV3 genome from 1 1 .7% to 30.8% was carried out. Analysis of the determined sequences revealed the primary structure of important viral gene products coded by E2 including BAV3 DNA pol and precursor to terminal protein. Comparative analysis of these proteins with their counterparts from human and non human adenoviruses revealed important insights as to the evolutionary lineage of BAV3. In order to insert the kanamycin resistance gene in either E1 or E3, it was necessary to delete BAV3 sequences to accommodate the foreign gene so as not to exceed the limit of the packaging capacity of the virus. To construct a recombinant BAV3 in which a foreign gene was inserted in the deleted E1 region, an E1 shuttle vector was constructed. This involved the deletion from the viral sequences a region between 1.3% to 9% and inserting the kanamycin resistance gene to replace the deletion. The E1 shuttle vector contained the left (0%- 53.9%) segment of the genome and was expected to generate BAV3 recombinants that can be grown and propagated in cells that can complement the missing E1 functions. To construct a similar shuttle vector for E3 deletion, DNA sequences extending from 78.9% to 82.5% (1281 bp) were deleted from within the E3 region that had been cloned into a plasmid vector. The deleted region corresponds to those that have been shown to be non-essential for viral replication in cell culture. The resulting plasmid was used to construct another recombinant plasmid with BAV3 DNA sequences extending from 37.1% to 100% and with a deletion of E3 sequences that were replaced by kanamycin resistance gene. This shuttle plasmid was used in cotransfections with digested viral DNA in an attempt to rescue a recombinant BAV3 carrying the kanamycin resistance gene to replace the deleted E3. In spite of repeated attempts of transfection, El or E3 recombinant BAV3 were not isolated. It seems that other approaches should be applied to make a final conclusion on BAV3 infectivity

    Differential Subordination with Generalized Derivative Operator of Analytic Functions

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    Motivated by generalized derivative operator defined by the authors (El-Yagubi and Darus, 2013) and the technique of differential subordination, several interesting properties of the operator Dλ1,λ2,δm,b are given

    Tumor necrosis factor gene polymorphisms in advanced non-exudative age-related macular degeneration

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    Purpose: To investigate tumor necrosis factor (TNF)-α gene polymorphisms in advanced dry-type age-related macular degeneration (AMD) in a population from Northeastern Iran. Methods: In this case-control study, 50 patients with geographic macular atrophy and 73 gender-matched controls were enrolled. Genomic deoxyribonucleic acid (DNA) was extracted from the peripheral blood. Polymerase chain reaction was performed to analyze 2 candidate single nucleotide polymorphisms in the TNF-α gene, namely −1031 thymine (T)/cytosine (C) and −308 guanine (G)/adenine (A). Results: The distribution of the - 1031 T/C genotype was TT, 62%; TC, 36%; CC, 2% in the patients and TT, 60%; TC, 36%; CC, 4% in the controls (P = 0.94). Genotype analysis of TNF-α −308 also revealed no significant difference in distribution between patients (G, 78%; GA, 22%; AA, 0%) and controls (GG, 74%; GA, 23%; AA, 3%) (P = 0.51). None of the haplotypes nor alleles of studied TNF-α polymorphisms were significantly associated with advanced dry-type AMD. Conclusion: The findings of this study show that polymorphisms in the TNF-α gene, do not play an important role in dry-type AMD in the studied population
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