scholarly journals Differential inhibitory effects of sulfated polysaccharides and polymers on the replication of various myxoviruses and retroviruses, depending on the composition of the target amino acid sequences of the viral envelope glycoproteins.

1991 ◽  
Vol 35 (12) ◽  
pp. 2515-2520 ◽  
Author(s):  
M Hosoya ◽  
J Balzarini ◽  
S Shigeta ◽  
E De Clercq
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
Viral Envelope ◽  
Sulfated Polysaccharides ◽  
Envelope Glycoproteins ◽  
Inhibitory Effects ◽  
Target Amino Acid

scholarly journals Two Genetic Differences between Closely Related Zika Virus Strains Determine Pathogenic Outcome in Mice

2020 ◽  
Vol 94 (20) ◽  
Author(s):  
Derek L. Carbaugh ◽  
Shuntai Zhou ◽  
Wes Sanders ◽  
Nathaniel J. Moorman ◽  
Ronald Swanstrom ◽  
...  
Keyword(s):  
Amino Acid ◽  
Mouse Models ◽  
Zika Virus ◽  
Clinical Manifestations ◽  
Amino Acid Sequences ◽  
Viral Envelope ◽  
Laboratory Research ◽  
Balanced Polymorphism ◽  
E Protein ◽  
Virus Strains

ABSTRACT Recent Zika virus (ZIKV) outbreaks and unexpected clinical manifestations of ZIKV infection have prompted an increase in ZIKV-related research. Here, we identify two strain-specific determinants of ZIKV virulence in mice. We found that strain H/PF/2013 caused 100% lethality in Ifnar1−/− mice, whereas PRVABC59 caused no lethality; both strains caused 100% lethality in Ifnar1−/− Ifngr1−/− double-knockout (DKO) mice. Deep sequencing revealed a high-frequency variant in PRVABC59 not present in H/PF/2013: a G-to-T change at nucleotide 1965 producing a Val-to-Leu substitution at position 330 of the viral envelope (E) protein. We show that the V330 variant is lethal on both virus strain backgrounds, whereas the L330 variant is attenuating only on the PRVABC59 background. These results identify a balanced polymorphism in the E protein that is sufficient to attenuate the PRVABC59 strain but not H/PF/2013. The consensus sequences of H/PF/2013 and PRVABC59 differ by 3 amino acids, but these were not responsible for the difference in virulence between the two strains. H/PF/2013 and PRVABC59 differ by an additional 31 noncoding or silent nucleotide changes. We made a panel of chimeric viruses with identical amino acid sequences but nucleotide sequences derived from H/PF/2013 or PRVABC59. We found that 6 nucleotide differences in the 3′ quarter of the H/PF/2013 genome were sufficient to confer virulence in Ifnar1−/− mice. Altogether, our work identifies a large and previously unreported difference in virulence between two commonly used ZIKV strains, in two widely used mouse models of ZIKV pathogenesis (Ifnar1−/− and Ifnar1−/− Ifngr1−/− DKO mice). IMPORTANCE Contemporary ZIKV strains are closely related and often used interchangeably in laboratory research. Here, we identify two strain-specific determinants of ZIKV virulence that are evident in only Ifnar1−/− mice but not Ifnar1−/− Ifngr1−/− DKO mice. These results identify a balanced polymorphism in the E protein that is sufficient to attenuate the PRVABC59 strain but not H/PF/2013. We further identify a second virulence determinant in the H/PF/2013 strain, which is driven by the viral nucleotide sequence but not the amino acid sequence. Altogether, our work identifies a large and previously unreported difference in virulence between two commonly used ZIKV strains, in two widely used mouse models of ZIKV pathogenesis. Our results highlight that even very closely related virus strains can produce significantly different pathogenic phenotypes in common laboratory models.

Co-evolution analysis to predict protein–protein interactions within influenza virus envelope

2014 ◽  
Vol 12 (02) ◽  
pp. 1441008 ◽  
Author(s):  
Ramil R. Mintaev ◽  
Andrei V. Alexeevski ◽  
Larisa V. Kordyukova
Keyword(s):  
Amino Acid ◽  
Protein Interactions ◽  
Influenza A ◽  
Matrix Protein ◽  
Amino Acid Sequences ◽  
Viral Envelope ◽  
Research Database ◽  
Virus Envelope ◽  
Physical Constraints ◽  
Matrix Protein M1

Interactions between integral membrane proteins hemagglutinin (HA), neuraminidase (NA), M2 and membrane-associated matrix protein M1 of influenza A virus are thought to be crucial for assembly of functionally competent virions. We hypothesized that the amino acid residues located at the interface of two different proteins are under physical constraints and thus probably co-evolve. To predict co-evolving residue pairs, the EvFold ( http://evfold.org ) program searching the (nontransitive) Direct Information scores was applied for large samplings of amino acid sequences from Influenza Research Database ( http://www.fludb.org/ ). Having focused on the HA, NA, and M2 cytoplasmic tails as well as C-terminal domain of M1 (being the less conserved among the protein domains) we captured six pairs of correlated positions. Among them, there were one, two, and three position pairs for HA–M2, HA–M1, and M2–M1 protein pairs, respectively. As expected, no co-varying positions were found for NA–HA, NA–M1, and NA–M2 pairs obviously due to high conservation of the NA cytoplasmic tail. The sum of frequencies calculated for two major amino acid patterns observed in pairs of correlated positions was up to 0.99 meaning their high to extreme evolutionary sustainability. Based on the predictions a hypothetical model of pair-wise protein interactions within the viral envelope was proposed.

scholarly journals Identification of the Fusion Peptide-Containing Region in Betacoronavirus Spike Glycoproteins

2016 ◽  
Vol 90 (12) ◽  
pp. 5586-5600 ◽  
Author(s):  
Xiuyuan Ou ◽  
Wangliang Zheng ◽  
Yiwei Shan ◽  
Zhixia Mu ◽  
Samuel R. Dominguez ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Cell Fusion ◽  
Fusion Proteins ◽  
Virus Entry ◽  
Amino Acid Sequences ◽  
Viral Envelope ◽  
Class I ◽  
Viral Fusion ◽  
Viral Fusion Proteins

ABSTRACTThe fusion peptides (FP) play an essential role in fusion of viral envelope with cellular membranes. The location and properties of the FPs in the spike (S) glycoproteins of different coronaviruses (CoV) have not yet been determined. Through amino acid sequence analysis of S proteins of representative CoVs, we identified a common region as a possible FP (pFP) that shares the characteristics of FPs of class I viral fusion proteins, including high Ala/Gly content, intermediate hydrophobicity, and few charged residues. To test the hypothesis that this region contains the CoV FP, we systemically mutated every residue in the pFP of Middle East respiratory syndrome betacoronavirus (MERS-CoV) and found that 11 of the 22 residues in the pFP (from G953 to L964, except for A956) were essential for S protein-mediated cell-cell fusion and virus entry. The synthetic MERS-CoV pFP core peptide (955IAGVGWTAGL964) induced extensive fusion of liposome membranes, while mutant peptide failed to induce any lipid mixing. We also selectively mutated residues in pFPs of two other β-CoVs, severe acute respiratory syndrome coronavirus (SARS-CoV) and mouse hepatitis virus (MHV). Although the amino acid sequences of these two pFPs differed significantly from that of MERS-CoV and each other, most of the pFP mutants of SARS-CoV and MHV also failed to mediate membrane fusion, suggesting that these pFPs are also the functional FPs. Thus, the FPs of 3 different lineages of β-CoVs are conserved in location within the S glycoproteins and in their functions, although their amino acid sequences have diverged significantly during CoV evolution.IMPORTANCEWithin the class I viral fusion proteins of many enveloped viruses, the FP is the critical mediator of fusion of the viral envelope with host cell membranes leading to virus infection. FPs from within a virus family, like influenza viruses or human immunodeficiency viruses (HIV), tend to share high amino acid sequence identity. In this study, we determined the location and amino acid sequences of the FPs of S glycoproteins of 3 β-CoVs, MERS-CoV, SARS-CoV, and MHV, and demonstrated that they were essential for mediating cell-cell fusion and virus entry. Interestingly, in marked contrast to the FPs of influenza and HIV, the primary amino acid sequences of the FPs of β-CoVs in 3 different lineages differed significantly. Thus, during evolution the FPs of β-CoVs have diverged significantly in their primary sequences while maintaining the same essential biological functions. Our findings identify a potential new target for development of drugs against CoVs.

Hydrophobic-at-Interface Regions in Viral Fusion Protein Ectodomains

2000 ◽  
Vol 20 (6) ◽  
pp. 519-533 ◽  
Author(s):  
José L. Nieva ◽  
Tatiana Suárez
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
Viral Envelope ◽  
Fusion Pore ◽  
Viral Fusion ◽  
New Approach ◽  
Viral Fusion Protein ◽  
Membrane Partitioning ◽  
Viral Glycoproteins ◽  
New Procedures

In this chapter we shall describe how to apply the hydrophobicity-at-interface scale, as proposed by Wimley and White [Wimley, W. C. and White, S. H. (1996) Nature Struct. Biol. 3:842–848], to the detection of amino acid sequences of viral envelope glycoproteins putatively engaged in interactions with the target membranes. In addition, a new approach will be briefly introduced to infer the bilayer location at equilibrium of membrane-partitioning sequences. The use of these new procedures may be important in describing the molecular mechanism leading to the formation of a fusion pore by viral glycoproteins.

Diversity of Primary Structures of the Carboxy-terminal Regions of Mammalian Fibrinogen Aα-Chains

1993 ◽  
Vol 69 (04) ◽  
pp. 351-360 ◽  
Author(s):  
Masahiro Murakawa ◽  
Takashi Okamura ◽  
Takumi Kamura ◽  
Tsunefumi Shibuya ◽  
Mine Harada ◽  
...  
Keyword(s):  
Amino Acid ◽  
Rhesus Monkey ◽  
Syrian Hamster ◽  
Tandem Repeats ◽  
Mammalian Species ◽  
Amino Acid Sequences ◽  
Point Of View ◽  
Cross Linking ◽  
Amino Terminal ◽  
Rgd Sequence

SummaryThe partial amino acid sequences of fibrinogen Aα-chains from five mammalian species have been inferred by means of the polymerase chain reaction (PCR). From the genomic DNA of the rhesus monkey, pig, dog, mouse and Syrian hamster, the DNA fragments coding for α-C domains in the Aα-chains were amplified and sequenced. In all species examined, four cysteine residues were always conserved at the homologous positions. The carboxy- and amino-terminal portions of the α-C domains showed a considerable homology among the species. However, the sizes of the middle portions, which corresponded to the internal repeat structures, showed an apparent variability because of several insertions and/or deletions. In the rhesus monkey, pig, mouse and Syrian hamster, 13 amino acid tandem repeats fundamentally similar to those in humans and the rat were identified. In the dog, however, tandem repeats were found to consist of 18 amino acids, suggesting an independent multiplication of the canine repeats. The sites of the α-chain cross-linking acceptor and α2-plasmin inhibitor cross-linking donor were not always evolutionally conserved. The arginyl-glycyl-aspartic acid (RGD) sequence was not found in the amplified region of either the rhesus monkey or the pig. In the canine α-C domain, two RGD sequences were identified at the homologous positions to both rat and human RGD S. In the Syrian hamster, a single RGD sequence was found at the same position to that of the rat. Triplication of the RGD sequences was seen in the murine fibrinogen α-C domain around the homologous site to the rat RGDS sequence. These findings are of some interest from the point of view of structure-function and evolutionary relationships in the mammalian fibrinogen Aα-chains.

Bovine Factors X1And X2: Activation Peptide Based Chromatographic Differences

1979 ◽  
Author(s):  
Takashi Morita ◽  
Craig Jackson
Keyword(s):  
Amino Acid ◽  
Anion Exchange ◽  
Gel Filtration ◽  
Heart Association ◽  
Personal Communication ◽  
Exchange Chromatography ◽  
Amino Acid Sequences ◽  
Factor X ◽  
Activation Peptide ◽  
Activation Peptides

Bovine Factor X is eluted in two forms (X1and X2) from anion exchange chromatographic columns. These two forms have indistinguishable amino acid compositions, molecular weights and specific activities. The amino acid sequences containing the γ-carboxyglutamic acid residues have been shown to be identical in X1 and X2(H. Morris, personal communication). An activation peptide is released from the N-terminal region of the heavy chain of Factor X by an activator from Russell’s viper venom. This peptide can be isolated after activation by gel filtration on Sephadex G-100 under nondenaturing conditions. The activation peptides from a mixture of Factors X1 and X2 were separated into two forms by anion-exchange chromatography. The activation peptide (AP1) which eluted first was shown to be derived from Factor X1. while the activation peptiae (AP2) which eluted second was shown to be derived from X2 on the basis of chromatographic separations carried out on Factors X1 and X2 separately. Factor Xa was eluted as a symmetrical single peak. On the basis of these and other data characterizing these products, we conclude that the difference between X1 and X2 are properties of the structures of the activation peptides. (Supported by a grant HL 12820 from the National Heart, Lung and Blood Institute. C.M.J. is an Established Investigator of the American Heart Association).

Application of the Innovative and Non-Invasive Technique, Molecular Music Therapy (MMT), Bio-Frequency Therapy, for the Treatment of a Wide Range of Disorders and Pathologies, with Consequent Verification of Molecular Parameters by Using Bi-Digital O-Ring Test (BDORT)

2020 ◽  
Vol 44 (3) ◽  
pp. 177-189
Author(s):  
Momir Dunjic ◽  
Stefano Turini ◽  
Dejan Krstic ◽  
Katarina Dunjic ◽  
Marija Dunjic ◽  
...  
Keyword(s):  
Amino Acid ◽  
Music Therapy ◽  
Amino Acid Sequences ◽  
Sirtuin 1 ◽  
Ring Test ◽  
Invasive Technique ◽  
Specific Gene ◽  
Radiofrequency Therapy ◽  
Wide Range ◽  
Clinical Pictures

Radiofrequency therapy is an unconventional method, already applied for some time, with numerous results in numerous clinical pictures. Our group has developed a software, later called SONGENPROT-SOLARIS, capable of directly converting nucleotide sequences (DNA and/or RNA) and amino acid sequences (polypeptides and proteins) into musical sequences, based on mathematic matrices, designed by the French physicist and musician Joel Sternheimer, which allows to associate a musical note with a nucleotide or an amino acid. Innovation in our software is that, in the algorithm that defines it, a variant is directly implemented that allows the reproduction of sounds, phase-shifted by 30 Hz, between one ear and another reproducing the phenomenon of Binaural Tones, capable of induce a specific brain activity and also the release of particles called solitons. Thanks to this software we have developed a technique called MMT (Molecular Music Therapy) and currently, we are in the phase of applying the technique on a cohort of 91 patients, with a high spectrum of clinical pictures, examining the same, using the technique Bi-Digital-ORing-Test (BDORT), before and after treatment with MMT. Aim of project is to stimulate the expression of a specific gene (the same genetic sequence that the patient listens to, translated into music), only through the use of sound sequences. We have concentrated our attention on three main molecules: Sirtuin-1, Telomers and TP-53. The results obtained with BDORT, after treatment with MMT, showed a significant increase in the values of the three molecules, on all the examined patients, demonstrating the operative efficacy of the technique and the its applicability to numerous diseases. In order to confirm the data obtained by BDORT, we propose, with the help of an accredited laboratory, to perform epigenetic tests on the three parameters listed above, paving the way to understanding how frequencies can influence gene expression.

The Inducing Roles of the New Isolated Bursal Hexapeptide and Pentapeptide on the Immune Response of AIV Vaccine in Mice

2019 ◽  
Vol 26 (7) ◽  
pp. 542-549 ◽  
Author(s):  
Shan Shan Hao ◽  
Man Man Zong ◽  
Ze Zhang ◽  
Jia Xi Cai ◽  
Yang Zheng ◽  
...  
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Amino Acid ◽  
T Cell ◽  
Antigen Presentation ◽  
Amino Acid Sequences ◽  
Cell Subpopulation ◽  
Igg Antibody ◽  
Antibody Titers ◽  
Specific Igg

Background: Bursa of Fabricius is the acknowledged central humoral immune organ. The bursal-derived peptides play the important roles on the immature B cell development and antibody production. Objective: Here we explored the functions of the new isolated bursal hexapeptide and pentapeptide on the humoral, cellular immune response and antigen presentation to Avian Influenza Virus (AIV) vaccine in mice immunization. Methods: The bursa extract samples were purified following RP HPLC method, and were analyzed with MS/MS to identify the amino acid sequences. Mice were twice subcutaneously injected with AIV inactivated vaccine plus with two new isolated bursal peptides at three dosages, respectively. On two weeks after the second immunization, sera samples were collected from the immunized mice to measure AIV-specific IgG antibody levels and HI antibody titers. Also, on 7th day after the second immunization, lymphocytes were isolated from the immunized mice to detect T cell subtype and lymphocyte viabilities, and the expressions of co-stimulatory molecule on dendritic cells in the immunized mice. Results: Two new bursal hexapeptide and pentapeptide with amino acid sequences KGNRVY and MPPTH were isolated, respectively. Our investigation proved the strong regulatory roles of bursal hexapeptide on AIV-specific IgG levels and HI antibody titers, and lymphocyte viabilities, and the significant increased T cells subpopulation and expressions of MHCII molecule on dendritic cells in the immunized mice. Moreover, our findings verified the significantly enhanced AIV-specific IgG antibody and HI titers, and the strong increased T cell subpopulation and expressions of CD40 molecule on dendritic cells in the mice immunized with AIV vaccine and bursal pentapeptide. Conclusion: We isolated and identified two new hexapeptide and pentapeptide from bursa, and proved that these two bursal peptides effectively induced the AIV-specific antibody, T cell and antigen presentation immune responses, which provided an experimental basis for the further clinical application of the bursal derived active peptide on the vaccine improvement.

Corticosteroid Catabolism by Klebsiella pneumoniae as a Possible Mechanism for Increased Pneumonia Risk

2019 ◽  
Vol 20 (4) ◽  
pp. 309-316 ◽  
Author(s):  
Pritam Chattopadhyay ◽  
Goutam Banerjee
Keyword(s):  
Amino Acid ◽  
Klebsiella Pneumoniae ◽  
Kegg Pathway ◽  
Degradation Pathway ◽  
Amino Acid Sequences ◽  
Biological Mechanism ◽  
Clinical Strains ◽  
Catabolism Pathway ◽  
Steroid Catabolism ◽  
Nutrition Source

Background: Several strains of Klebsiella pneumoniae are responsible for causing pneumonia in lung and thereby causing death in immune-suppressed patients. In recent year, few investigations have reported the enhancement of K. pneumoniae population in patients using corticosteroid containing inhaler. Objectives: The biological mechanism(s) behind this increased incidence has not been elucidated. Therefore, the objective of this investigating was to explore the relation between Klebsiella pneumoniae and increment in carbapenamase producing Enterobacteriaceae score (ICS). Methods: The available genomes of K. pneumoniae and the amino acid sequences of steroid catabolism pathway enzymes were taken from NCBI database and KEGG pathway tagged with UniPort database, respectively. We have used different BLAST algorithms (tBLASTn, BLASTp, psiBLAST, and delBLAST) to identify enzymes (by their amino acid sequence) involved in steroid catabolism. Results: A total of 13 enzymes (taken from different bacterial candidates) responsible for corticosteroid degradation have been identified in the genome of K. pneumoniae. Finally, 8 enzymes (K. pneumoniae specific) were detected in four clinical strains of K. pneumoniae. This investigation intimates that this ability to catabolize corticosteroids could potentially be one mechanism behind the increased pneumonia incidence. Conclusion: The presence of corticosteroid catabolism enzymes in K. pneumoniae enhances the ability to utilize corticosteroid for their own nutrition source. This is the first report to demonstrate the corticosteroid degradation pathway in clinical strains of K. pneumoniae.

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