Loss of Human Tyrosinase DOPA Oxidase Activity in Artificial M374 Arg and M 374 Lys Mutants

      Tyrosinase (Ec: 1.14.18.1) is a copper - containing enzyme which is distributed in all domains of life such as prokaryote, eukaryote, mammals, invertebrates and plants. Tyrosinase catalyzes the oxidation of monophenols to diphenols and diphenols to o-quinones . The tyrosinase crystallographic data shows two histidine -rich regions named CuA and CuB. A loop containing residues M374, S375 and V377 connects the CuA and CuB Centers. This loop is essential for stability of the enzyme. In this study, site directed mutagenesis was used for the replacement of M374 by Arginine and Lysine.in synthesized cDNA cloned in pET 28b (+) . These mutations don't affect the orientation of the Histidin 367(H367) side chain, resulting in loss of activity.

DUŽINSKO-MASENI ODNOS I ODNOS DUŽINA-DUŽINA KOD ŠEST VRSTA RIBA IZ PERZIJSKOG ZALJEVA

Length–weight relationship (LWR) and length–length relationship (LLR) were estimated for six species of ponyfishes captured in the Persian Gulf, Iran. The LWRs indicated isometric growth in ornate ponyfish (Equulites lineolatus), common ponyfish (Leiognathus equulus) and deep pugnose ponyfish (Secutor ruconius) species, positive allometric growth in striped ponyfish (Aurigequula fasciata) and negative allometric growth in decorated ponyfish (Nuchequula gerreoides) and orangefin ponyfish (Photopectoralis bindus). LWR and LLR parameters for one of the species (E. lineolatus) are given for the first time. The relationships between TL, FL and SL were all linear and highly correlated (for all cases: r2 > 0.97).Dužinsko-maseni odnos (LWR) i odnos dužina-dužina (LLR) procijenjene su na šest vrsta riba ulovljenih u Perzijskom zaljevu, Iran. Dužinsko-masenim odnosom ustanovljen je izometrijski rast kod vrsta Equulites lineolatus, Leiognathus equulus i Secutor ruconius, pozitivni alometrijski rast kod Aurigequula fasciata i negativan alometrijski rast kod Nuchequula gerreoides i Photopectoralis bindus. LWR i LLR parametri vrste E. lineolatus prikazani su po prvi put. Odnosi između TL, FL i SL su linearni i visoko korelirani (za sve slučajeve: r2> 0,97)

Association of Fibroblast Growth Factor (Fgf-21) as a Screening Biomarker for Chronic Progressive External Ophthalmoplesia

Purpose: To investigate whether or not fibroblast growth factor (FGF-21) can be used as a screening biomarker in chronic progressive external ophthalmoplesia (CPEO) patients.Methods: FGF-21 concentration was measured in the serum of 24 patients with CEPO phenotype and 24 control samples by enzyme-linked immunosorbent assay (ELISA) and determined the deletion of mitochondrial genome by multiplex polymerase chain reaction (PCR).Results: FGF-21 concentration in 50 % of CPEO patients showed notable differences from that in control subjects. FGF-21 concentration ratio in patient group, 2 disorder control groups (mitochondrial and non-mitochondrial) and normal group, respectively, was 294.87 } 42.10 (p < 0.0001), 761.78} 75.07 (p < 0.0001), 124.26 } 12.27 (p = 0.1203), 69.27 } 10.09 (p = 0.2195). A statistically significant inverse correlation between FGF-21 concentration and age onset was found, with a significant difference (p < 0.05) in the age group . 19 years (mean FGF-21  concentration, 460.36 pg/mL) and for the age group . 51years (mean concentration FGF-21, 57.87 pg/mL. Surprisingly, there was no significant difference between FGF-21 concentration and age in the mid-age group (20 . 50 years) .Conclusion: These findings indicate that FGF-21 concentration significantly increases in CPEO patients like in other mitochondrial disorders and this factor can be used as a biomarker in primary diagnosis of mitochondrial disorders. In this regard, FGF-21 assay is only valid in teenagers and the >50 years age group who show acute symptoms.Keywords: Chronic progressive external ophthalmoplesia, Fibroblast growth factor-21, Mitochondrial disorders, Ophthalmoplesia, Biomarke

Antisense PNA accumulates in Escherichia coli and mediates a long post-antibiotic effect

Antisense agents that target growth-essential genes display surprisingly potent bactericidal properties. In particular, peptide nucleic acid (PNA) and phosphorodiamidate morpholino oligomers linked to cationic carrier peptides are effective in time kill assays and as inhibitors of bacterial peritonitis in mice. It is unclear how these relatively large antimicrobials overcome stringent bacterial barriers and mediate killing. Here we determined the transit kinetics of peptide-PNAs and observed an accumulation of cell-associated PNA in Escherichia coli and slow efflux. An inhibitor of drug efflux pumps did not alter peptide-PNA potency, indicating a lack of active efflux from cells. Consistent with cell retention, the post-antibiotic effect (PAE) of the anti-acyl carrier protein (acpP) peptide-PNA was greater than 11 hours. Bacterial cell accumulation and a long PAE are properties of significant interest for antimicrobial development.Peer reviewe

Dendrosomal nanocurcumin prevents EBV-associated cell transformation by targeting the lytic cycle genes of the Epstein-Barr virus in the generation of lymphoblastoid cell line

Objective(s): Targeting the lytic cycle of the Epstein-Barr virus (EBV) has been considered a new treatment strategy for malignancies caused by this virus.  This study aimed to investigate the effect of Dendrosomal NanoCurcumin (DNC) to prevent cell transformation and inhibit the expression of viral lytic gene expression in the generation of lymphoblastoid cell line (LCL).Materials and Methods: Cell viability of LCLs and PBMCs was performed by MTT assay, and flow cytometry (Annexin/PI) was used for evaluation of apoptosis. CD markers on the surface of generated LCL (CD19) cells were examined for cell validation. The effect of DNC on transformation was evaluated by examining cell morphology and determining the expression level of lytic genes BZLF1, Zta, BHRF1, and BRLF1 of EBV using Real-time PCR. Student’s t-test was used for statistical analysis.Results: The MTT assay showed that DNC can inhibit the proliferation of LCL in a dose-dependent manner. The 50% cytotoxic concentration (CC50) of DNC and curcumin for LCL was determined 38.8 µg/ml and 75 µg/ml, respectively after 72 hr. Also, Real-time PCR data analysis showed that DNC in 30 µg/ml concentration significantly inhibited cell transformation in the LCL and significantly reduced viral lytic genes such as BZLF1, Zta, BHRF1, and BRLF1expression compared to control.Conclusion: Overall, these findings show that DNC reduces the expression of the viral lytic cycle genes and also the induction of cell apoptosis and finally prevents the generation of LCL

Immunogenicity of a novel tetravalent dengue envelope protein domain III-based antigen in mice

Dengue virus is a mosquito-borne pathogen that causes dengue diseases. All four serotypes of dengue virus are infectious for humans. Therefore, an efficacious dengue vaccine should be tetravalent to provide protection against all types of virus. The goal of this study was to design a new tetravalent recombinant protein from envelope protein of dengue viruses to induce virus-neutralizing antibodies against all four serotypes in mice. A chimeric protein was designed from domain III of envelope protein of all serotypes of dengue virus. Four domain III fragments were linked together by alpha helix making linkers. The final sequence of the designed protein was analyzed in silico and the coding gene sequence was deduced by reverse translation. After cloning and expression of the recombinant protein (ED3-tetravalent protein), identity of the purified protein was confirmed using a pan-dengue specific monoclonal antibody in Western blotting. Then, the immunogenicity of the purified protein was studied in mice using antibody titration. The efficacy of induced antibodies in neutralization of the virus was studies by FRNT method. Furthermore, the induction of cellular immunity was studied by measurement of cytokines using ELISA method and measurement of lymphocyte proliferation using MTT assay. The ED3-tetravalent protein was able to enhance neutralizing immunogenic response against all four dengue serotypes; in similar way to that of tetravalent formulation of four individual domain III-based polypeptides. It is suggested that the ED3-tetravalent fusion protein can induce broadly neutralizing antibody responses against all four serotypes of dengue virus in mice

Signaling pathways involved in chronic myeloid leukemia pathogenesis: the importance of targeting Musashi2-Numb signaling to eradicate leukemia stem cells

Objective(s): Chronic myeloid leukemia (CML) is a myeloid clonal proliferation disease defining by the presence of the Philadelphia chromosome that shows the movement of BCR-ABL1. In this study, the critical role of the Musashi2-Numb axis in determining cell fate and relationship of the axis to important signaling pathways such as Hedgehog and Notch that are essential for self-renewal pathways in CML stem cells will be reviewed meticulously.Materials and Methods: In this review, a PubMed search using the keywords of Leukemia, signaling pathways, Musashi2-Numb was performed, and then we summarized different research works.Results: Although tyrosine kinase inhibitors such as Imatinib significantly kill and remove the cell with BCR-ABL1 translocation, they are unable to target BCR-ABL1 leukemia stem cells. The main problem is stem cells resistance to Imatinib therapy. Therefore, the identification and control of downstream molecules/ signaling route of the BCR-ABL1 that are involved in the survival and self-renewal of leukemia stem cells can be an effective treatment strategy to eliminate leukemia stem cells, which supposed to be cured by Musashi2-Numb signaling pathway.Conclusion: The control of molecules /pathways downstream of the BCR-ABL1 and targeting Musashi2-Numb can be an effective therapeutic strategy for treatment of chronic leukemia stem cells. While Musashi2 is a poor prognostic marker in leukemia, in treatment and strategy, it has significant diagnostic value