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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Proteins,Energy transfer,Plant Roots,Plant Shoots,Xylem
- چکیده:
- چکیده انگلیسی: Background: Root to shoot connection and transfer of information seems to be taken place mostly via the transmissions of signal molecules, secondary metabolites, amino acids, hormones and proteins, through xylem sap. Examination of earlier reports is indicative of relatively high levels of conservation in xylem sap protein compositions. Apparently these protein molecules are being synthesized in roots in response to environmental changes and get transported to aerial plant parts after secretion into xylem sap.
Objectives: In order to comprehend this so-called passive signaling, some questions need to be answered: 1) Do these proteins have the capability to act as signals? 2) How much energy does root spend for the biosynthesis of the secreted proteins? How similar is the amount of energy that root cells spent for the biosynthesis of intra- and extra-cellular proteins?
Materials and Methods: Reported xylem sap proteins curated from Arabidopsis, maize and soybean. Their sequences were put under scrutiny in terms of considering their mobility, and physical and chemical properties. Metabolic energy required for their biosynthesis along with the energy hidden in their peptide bonds were calculated and compared with random non-xylem sap proteins as control.
Results: Xylem sap proteins were significantly smaller than the root proteins, while they were bigger in size when compared to the leaf group. Xylem protein pIs were significantly higher than the control proteins in different plants. Similarly, the protein stability was higher for xylem sap proteins in comparison with roots and leaves in all analyzed plants, except for soybean that the stability was indifferent between xylem and root. The data were suggestive a significantly lower energy consumption for the synthesis of xylem sap proteins.
Conclusions: Lower energy consumption may suggest an economical route of communication between roots and shoots in plants that mainly rely on symplastic signaling.- انتشار مقاله: 17-07-1395
- نویسندگان: Mehri Rostaminedjad,Hossein Askari,Maryam Zakavi,Masood Soltani Nadjafabadi,Naser Farrokhi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: MicroRNA,Brassica rapa,Expressed sequence tag,Homology search,Non-protein coding RNA
- چکیده:
- چکیده انگلیسی: Background: Micro RNAs (miRNAs) are a pivotal part of non-protein-coding endogenous small RNA molecules that regulate the genes involved in plant growth and development, and respond to biotic and abiotic environmental stresses posttranscriptionally.
Objective: In the present study, we report the results of a systemic search for identifi cation of new miRNAs in B. rapa using homology-based ESTs (Expressed Sequence Tags) analysis and considering a series of fi ltration criteria.
Materials and Methods: Plant mature miRNA sequences were searched in non-protein coding ESTs registered in NCBI EST database. Zuker RNA folding algorithm was used to generate the secondary structures of the ESTs. Potential sequences were candidate as miRNA genes and characterized evolutionarily only and if only they fi t some described criteria. Also, the web tool psRNATarget was applied to predict candidate B. rapa miRNA targets.
Results: In this study, 10 novel miRNAs from B. rapa belonging to 6 miRNA families were identifi ed using EST-based homology analysis by considering a series of fi ltration criteria. All potent miRNAs appropriate fold back structure. Several potential targets with known/unknown functions for these novel miRNAs were identifi ed. The target genes mainly encode transcription factors, enzymes, DNA binding proteins, disease resistance proteins, carrier proteins and other biological processes.
Conclusions: MicroRNA having diverse functions in plant species growth, development and evolution by post transcriptionally regulating the levels of specifi c transcriptome so by eff ecting on their translation products. Research in miRNA led to the identifi cation of many miRNAs and their regulating genes from diverse plant species.- انتشار مقاله: 16-08-1394
- نویسندگان: Behzad Hajieghrari,Naser Farrokhi,Bahram Goliaei,Kaveh Kavousi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Biotechnology
- نوع مقاله: Journal Article
- کلمات کلیدی: Biocontrol,bacteriocin,Protein sequencing,Taguchi orthogonal array,Xanthomonas citri
- چکیده:
- چکیده انگلیسی: Background: Xanthomonas citri subsp. citri (Xcc), the causative agent of bacterial citrus canker, has affected citriculture worldwide. Varieties of means have been used to minimize its devastating effects, but no attention has been given to bacteriocins. Objectives: Here and for the first time, we report the isolation and characterization of two novel bacteriocins. Materials and Methods: Secretome containing bacteriocins of isolated bacteria was separated via SDS-PAGE. Each isolated protein band was characterized and checked for its efficacy in controlling two pathogenic isolates of Xcc via disk diffusion assay. The effects of varieties of carbon, nitrogen and phosphate sources were evaluated on both bacterial growth and bacteriocin production via Taguchi orthogonal method. Results: The two bacteriocins showed an activity up to 55ºC that were sensitive to proteases suggesting being protein in nature. Analysis of SDS-PAGE purified protein bands of bacterial secretomes with demonstrated potency against Xcc revealed the presence of peptides with relative molecular masses of 16.9 and 17 kDa for Cronobacter and Enterobacter, respectively. Sequence analysis of peptides revealed an HCP1 family VI secretion system homologue for Cronobacter (YP_001439956) and pilin FimA homologue for Enterobacter (CBK85798.1). A Taguchi orthogonal array was also implemented to determine the effect of temperature and eight other chemical factors on bacteriocin production for each bacterium. Conclusions: Two peptides with novel antibacterial activities effective against Xcc were isolated, characterized and conditions were optimized for their higher production.
- انتشار مقاله: 17-10-1393
- نویسندگان: Dariush Gholami,Tannaz Goodarzi,Saeed Aminzadeh,Seyed Mehdi Alavi,Nasrin Kazemipour,Naser Farrokhi
- مشاهده
- جایگاه : پژوهشی
- مجله: Advanced Research in Microbial Metabolites & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Amylopullulanase,Pullulan,Recombinant protein,Zymogram
- چکیده:
- چکیده انگلیسی: Starch debranching enzymes that merely hydrolyze α-(1→6) glycosidic linkages are classified into isoamylases (EC 3.2.1.68) and pullulanases (EC 3.2.1.41). An exception to this definition would be amylopullulanase, a type of pullulanase that is capable of cleaving both α-(1→4) and α-(1→6) linkages. Amylopullulanases are in demand in liquid sugar industries to generate glucose and some other starch derivatives. Pullulanases can be used in conjunction with amylases to improve sugar availability during sugar syrup production. Here, a thermophilic Cohnella sp. A01 amylopullulanase (EC 3.2.1.41) gene, namely Coh4159, was PCR amplified and cloned in pET-26b(+) and transformed into BL21(DE3). Recombinant Coh4159 was heterologously expressed in the presence of 0.5 mM IPTG and purified via affinity chromatography, and further characterized. Enzyme activity was demonstrated via zymogram analysis in the presence of pullulan. The enzyme had a hydrolytic effect on pullulan with Vmax = 2.85 µmol.min-1 and Km = 0.5 mM. Temperature optima and pH were 60 ˚C and 6.0. In which the enzyme kept its activity at wide pH (4-9) and temperature (30-70 ˚C) ranges. The recombinant enzyme kept 50% of its activity for 60 min, 100 min and 120 min when incubated at 80, 70 and 60 ˚C, respectively. Amongst metal ions tested, Mn2+, and Ca2+ have improved the enzyme activity both at 5 and 10 mM. The results promise the capability of producing a commercial industrial enzyme, well-suited to liquid sugar syrup industry specification.
- انتشار مقاله: 02-11-1396
- نویسندگان: Parvin Valiulahi,Saeed Aminzadeh,Mehdi Shamsara,Naser Farrokhi,Jahan Alikhajeh
- مشاهده