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Numerous studies showed that lipid transfer proteins (LTPs) play important roles in flower, development, cuticular wax deposition and pathogen responses; however, their roles in abiotic stresses are relatively less reported. This study characterized the function of a maize LTP gene (ZmLTP3) during drought stress. ZmLTP3 gene was transferred into maize inbred line Jing2416; subsequently the glyphosate and drought tolerance of the over-expression (OE) lines were analyzed. Analysis showed that OE lines could significantly enhance drought tolerance. Transgenic maize lines OE6, OE7 and OE8 showed lower cell membrane damage, higher chlorophyll contents, higher protective enzymes activities, better growth and development under drought condition. The results strongly indicated that overexpression of ZmLTP3 could increase drought tolerances in maize.

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Better vaccines and new therapeutic drugs could be a successful breakthrough against intracellular bacteria. M. tuberculosis ABC transporter ATPase (Rv0986) plays a role in mycobacterial virulence by inhibiting phagosome-lysosome fusion. Thus, it could be a potential vaccine candidate. C. pneumoniae another important intracellular bacterium possesses a protein named CpB0255, which is homologous with the mycobacterial Rv0986. The aim of this study was the cloning, over-expression and purification of CpB0255 ABC transporter ATPase protein to study its biological properties. The immunogenicity and protective effect of recombinant chlamydial ATPase protein combined with Alum adjuvant were investigated in mice. The immunization resulted in the reduction of the number of viable C. pneumoniae in the lungs after challenge. Our results confirm that chlamydial ATPase induces protective immunity in mice.

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Acta Microbiologica et Immunologica Hungarica
Authors: Ildikó Faludi, Ágnes Csanádi, Ágnes Szabó, Katalin Burián, Valéria Endrész, and A. Miczák

Chlamydophila pneumoniae possesses a type III secretion system (TTSS), which allows the bacteria to secrete effector molecules into the inclusion membrane and into the cytosol of the host cell. Low calcium response protein H (LcrH), as a part of the TTSS, is a chaperone protein expressed from the middle to late stages of the chlamydial developmental cycle. Gene of LcrH (CPn0811) in a 6His-tagged form was cloned from C. pneumoniae CWL029, expressed and purified from Escherichia coli using the HIS-select TALON CellThru Resin. The purity was checked with mass spectrometry. The samples were used for immunization of BALB/c mice. The inducible E. coli clone, which over-expresses the chlamydial LcrH, permits the study of the biological properties of this protein.

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Iron deficiency is the most common nutritional disorder, affecting over 30% of the world’s human population. The primary method used to alleviate this problem is nutrient biofortification of crops so as to improve the iron content and its availability in food sources. The over-expression of ferritin is an effective method to increase iron concentration in transgenic crops. For the research reported herein, sickle alfalfa (Medicago falcata L.) ferritin was transformed into wheat driven by the seed-storage protein glutelin GluB-1 gene promoter. The integration of ferritin into the wheat was assessed by PCR, RT-PCR and Western blotting. The concentration of certain minerals in the transgenic wheat grain was determined by inductively coupled plasma-atomic emission spectrometry, the results showed that grain Fe and Zn concentration of transgenic wheat increased by 73% and 44% compared to nontransformed wheat, respectively. However, grain Cu and Cd concentration of transgenic wheat grain decreased significantly in comparison with non-transformed wheat. The results suggest that the over-expression of sickle alfalfa ferritin, controlled by the seed-storage protein glutelin GluB-1 gene promoter, increases the grain Fe and Zn concentration, but also affects the homeostasis of other minerals in transgenic wheat grain.

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Matrix metalloproteinases (MMPs) constitute a large family of enzymes that degrade extracellular matrix proteins (ECM). MMPs are implicated in different pathological conditions such as cancer. Bcl-2 and P53 are key controllers of programmed cell death (PCD) or apoptosis. The aim of the present study was to determine the MMP-9, P53 and Bcl-2 levels in Egyptian patients with Mycobacterium tuberculosis (MTB) (Group I) compared with healthy control individuals (Group II). The concentrations of serum MMP-9 were determined quantitatively using enzyme immunoassay (EIA). P53 and Bcl-2 levels were assayed by flow cytometric analysis using specific monoclones. MMP-9 level was significantly higher in MTB patients compared with healthy control. Similarly, P53 and Bcl-2 levels were increased in MTB patients compared with healthy ones. These data reflect the alteration of MMP-9 level during the course of MTB infection, accompanied with apparent dysregulation of cellular apoptosis as indicated by P53 and Bcl-2 over-expression.

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Abstract  

The over-expression of folate receptors in variety of neoplastic tissues makes radiolabeled folate conjugates potential agents for imaging and therapy of such cancers. With the aim of preparing an imaging agent for targeting folate receptors, folic acid has been conjugated with homocysteine for complexation with [99mTc(CO)3(H2O)3]+ core. The radiolabeled complex of the homocysteine-folate could be obtained in >95% radiochemical yield as observed by HPLC. Stability of complex in saline was studied and challenge studies with histidine and cysteine revealed kinetic stability of the complex. Lipophilicity of the radiolabeled complex (log P) was found to be 0.45. In vitro uptake of 99mTc(CO)3-labeled folic acid derivative was studied in KB cells and inhibition studies were carried out using 3H-folic acid and cold homocysteine–folate conjugate. The in vitro studies indicated loss of binding affinity of the derivative towards folate receptors.

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Nowadays, identification of the novel physio-biological and therapeutic functions of plant cysteine proteinase inhibitors “plant cystatins / phytocystatins” are the great of interests for molecular biologists. Whether for biochemical, structural or functional studies, their successful expression along with an easy purification method is required. To date, fusion tags are the best available tools that meet all those requirements. We report here the cloning and simple functional expression and purification of a barley putative cystatin in Escherichia coli cells. For the first time, a part of barley coding sequence containing a predicted active cystatin was amplified by polymerase chain reaction and expressed as maltose binding fusion protein in TB1 strain of E. coli cells using pMALc2X over-expression vector system without affecting the bacterial growth. The expressed product was purified by single step affinity chromatography from the soluble fraction of induced culture at a yield of about 37 mg/ liter of bacterial cell culture. The purified fused protein could efficiently inhibit papain activity in vitro without the cleavage of the fusion partner.

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The present study was designed to reveal possible common and specific neuroendocrine mechanisms of depressionand anxiety-like states in rodents. Animal models of depression and anxiety (in particular, posttraumatic stress disorder, PTSD) were applied including the learned helplessness and the stress-restress paradigms, respectively. Immunocytochemical staining revealed that depressive- and anxiety-like states in animals were accompanied by the rise in corticotropin-releasing hormone (CRH) immunoreactivity in the parvocellular division of the hypothalamic paraventricular nucleus (PVN). Decrease in vasopressin-immunoreactivity in early period of depressive-like state development was followed by the normalization of vasopressin content in the hypothalamic PVN in delayed period. Increased CRH and vasopressin immunoreactivity in the magnocellular part of the PVN in delayed period of anxiety-like state development was detected only in the stress-restress paradigm. These results suggest that CRH hyperdrive in the parvocellular PVN appears to be a common neuroendocrine abnormality for depressive- and anxiety-like states in animals, while over-expression of CRH and vasopressin in the magnocellular PVN represents a specific feature of anxiety/PTSD-like state.

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The effects of environment and the high molecular weight glutenins on some quality properties (sedimentation volume, % protein content, and starch pasting viscosity) of bread wheat mutant waxy lines were evaluated. Thirty-eight 100% amylose-free F 2 derived F 6 and F 7 lines were used. The results indicated that the environment did not influence sedimentation volume, mixograph parameters and starch viscosity parameters of waxy flour. Variation in the % protein content was determined mainly by the environment. The sedimentation volume and the mixograph peak development time were influenced by the variation at over expression of Bx7 and the mixograph peak development time was influenced by the Glu-D1 locus. One starch viscosity parameter, time to peak viscosity, was influenced by variation at the Glu-A1 locus. This parameter is significantly lower in the waxy lines than the parent line, which shows the influence of the waxy loci. No significant correlation was observed for sedimentation volume, mixograph parameters, protein content and viscosity parameters of waxy lines.

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It remains difficult to distinguish adenoid cystic carcinoma (ACC) from polymorphous low-grade adenocarcinoma (PLGA). Although these neoplasms exhibit nearly similar histologic patterns, their biologic behavior is significantly different. This study was carried out in an attempt to overcome the histological overlap between these tumors using immunohistochemical method for c-kit and galectin-3 proteins on twenty cases of salivary gland tumors including twelve ACC and eight PLGA. Results revealed positive cytoplasmic reactivity for c-kit in 100% of ACC cases and only in 25% of PLGA. On the other hand, galectin-3 expression was observed in 100% of both ACC and PLGA cases. Moreover, solid variant of ACC showed overexpression of both proteins than cribriform and tubular subtypes. Significant positive correlation between the two studied proteins in ACC and PLGA was also observed (p < 0.05). Upon these results, over expression of c-kit and galectin-3 in ACC cases supports the concept of solid variant as a high-grade tumor. Moreover, c-kit may be used as a helpful marker to distinguish ACC from PLGA in cases where the diagnosis can be challenging.

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