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Epidermal growth factor receptor or EGFR or Erb-1 is a membranal protein that acts as a receptor for the extracellular EGF proteins family. This protein is a part of a family of receptors called ErbB family which are all tyrosine kinases receptors. Mutations in the gene of this receptors can cause cancer.

The DENV is small structure that can only reproduce inside a host organism. There are 4 related dengue viruses- Degue-1, Dengue-2, Dengue-3, & Dengue4. All of them are present in the same areas of the world. The dengue virus has just about a sphere shaped structure comprised of the viral genome and capsid proteins bordered by an envelope and a shell of antigen. Subsequently infecting, the dengue virus takes over the host cell's system to replicate the viral RNA genome and viral antigens. Once matured, the resynthesized DENVs are discharged and continue to infect additional host cells.

The OmpA protein is one of the main outer-membrane proteins of a large array of Gram-negative bacteria such as A.salmonicida, Shigella dysenteriae and E.coli.OmpA’s major physiological functions include maintenance of the structural integrity and morphology of the cells and porin activity, as well as a role in conjugation and bacteriophage binding.Achromogenic atypical Aeromonas salmonicida is the causative agent of goldfish ulcer disease.Virulence of this bacterium is associated with the production of a paracrystalline outer membrane A-layer protein.The species specific structural gene for the monomeric form of A-protein was cloned into a pET-3d plasmid in order to express and produce a recombinant form of the protein in E.coli BL21(DE3). The induced protein was isolated from inclusion bodies by a simple solubilization-renaturation procedure and purified by ion exchange chromatography on Q-Sepharose to over 95% pure monomeric protein.Recombinant A-protein was compared by biochemical, immunological and molecular methods with the A-protein isolated from atypical A.salmonicida bacterial cells by the glycine and the membrane extraction methods.

The life cycle of Toxoplasma gondii has two phases. The coccidia like takes place only in members of the Felidae family which makes these animals the parasite's primary host. The asexual part of the life cycle can take place in any warm-blooded animal, like other mammals(including felines) and birds. T. gondii constructing daughter scaffolds within the mother cell. In the intermediate hosts (including felines), the parasite invades cells, forming intracellular so-called parasitophorous vacuoles containing bradyzoites, the slowly replicating form of the parasit. Vacuoles form tissue cysts mainly within the muscles and brain. Since they are within cells, the host's immune system does not detect these cysts. Resistance to antibiotics varies, but the cysts are very difficult to eradicate entirely. Within these vacuoles T. gondii propagates by a series of binary fissions until the infected cell eventually bursts and tachyzoites are released. Tachyzoites are the motile, asexually reproducing form of the parasite. Unlike the bradyzoites, the free tachyzoites are usually efficiently cleared by the host's immune response, although some manage to infect cells and form bradyzoites, thus maintaining the infection.

EPH Receptor B2 (EPHB2) is a part of the transmembrane Eph receptor tyrosine kinase family (RTKs) which binds proteins of the Ephrin family on adjacent cells. The interaction leads to contact-dependent bidirectional signaling into neighboring cells. Hippocampal neurons can release vesicles containing full length EPHB2, and these are taken up by neighboring glial cells. EPHB2 takes part in the guidance of commissural axons through the embryonic midline and regulates dendritic spines development and maturation and stimulates the formation of excitatory synapses.

Chikungunya is an infection caused by the chikungunya virus which is passed to humans by two species of mosquito of the genus Aedes: A. albopictus and A. aegypti. Animal reservoirs of the virus include monkeys, birds, cattle, and rodents. The features of the disease are a sudden onset of fever 2-4 days after exposure. The fever typically lasts 2-7 days, while the associated joint pains usually last weeks or months but sometimes years. The mortality rate is a little less than 1 in 1,000. The disease has occurred in outbreaks in Asia, Europe and the Americas since 2004. CHIKV is a single-stranded positive-sense RNA genome, 11,800 nts long which encodes 2 open reading frames. The nucleocapsid is tightly enveloped by a host-derived lipid bilayer (envelope) supporting the virus-encoded envelope proteins. 80 glycoprotein spikes are C- terminally anchored within the viral envelope. The structural polyprotein is translated from a viral sub genomic mRNA, while as the 5 structural proteins (capsid, E3, E2, 6K, E1) are translated as a single polyprotein, from which capsid (C) is cleaved off to encapsidate. The envelope polyprotein precursor E3-E2-6K-E1 is translocated to the endoplasmatic reticulum. Polyprotein is processed by host signalases, resulting in E3, E2 & E1 forming viral hetero-trimeric spikes. The viral spikes majorly contains E2 and E1 facilitate cell receptor recognition, cell entry thru pH-dependent endocytosis and support viral budding.

Ubiquitin-conjugating enzyme E2S (UBE2S) belongs to the ubiquitin-conjugating enzyme family. UBE2S is able to form a thiol ester linkage with ubiquitin in a ubiquitin activating enzyme-dependent manner, a typical property of ubiquitin carrier proteins. UBE2S catalyzes the covalent attachment of ubiquitin to other proteins. UBE2S acts as a crucial factor of the anaphase promoting complex/cyclosome (APC/C), which is a cell cycle-regulated ubiquitin ligase that controls progression through mitosis. UBE2S acts by purposely elongating 'Lys-11'-linked polyubiquitin chains initiated by the E2 enzyme UBE2C/UBCH10 on APC/C substrates, augmenting the degradation of APC/C substrates by the proteasome and promoting mitotic exit. UBE2S also acts by elongating ubiquitin chains initiated by the E2 enzyme UBE2D1/UBCH5 in vitro; it is nevertheless uncertain whether UBE2D1/UBCH5 acts as an E2 enzyme for the APC/C in vivo. UBE2S is also involved in ubiquitination and consequent degradation of VHL, resulting in an accumulation of HIF1A.

Hepatitis A virus cellular receptor 1 (HAVCR1) is a membrane receptor for both human hepatitis A virus (HHAV) and TIMD4. HAVCR1 is a type I trans-membrane structural glycoprotein located in the renal proximal tubule epithelial cells. HAVCR1 protein may be involved in the control of asthma and allergic diseases. The reference genome represents an allele which retains a MTTVP amino acid segment that presents defense against atopy in HHAV seropositive individuals.

SARS Coronavirus is an enveloped virus containing three outer structural proteins, namely the membrane (M), envelope (E), and spike (S) proteins. Spike (S)-glycoprotein of the virus interacts with a cellular receptor and mediates membrane fusion to allow viral entry into susceptible target cells. Accordingly, S-protein plays an important role in virus infection cycle and is the primary target of neutralizing antibodies.
It has recently been shown that SARS (severe acute respiratory syndrome) is caused by a human coronavirus. Human coronaviruses are the major cause of upper respiratory tract illness, such as the common cold, in humans. Coronaviruses are positive-stranded RNA viruses, featuring the largest viral RNA genomes known to date (27-31 kb). The first step in coronavirus infection is binding of the viral spike protein, a 139-kDa protein, to certain receptors on host cells. The spike protein is the main surface antigen of the coronavirus. The glycosilated spike protein (as well as the nucleocapsid protein) can be detected in infected cell culture supernatants with antisera from SARS patients.

IFNI30 inducible lysosomal thiol reductase (IFI30), is a part of the GILT family. IFI30 is a lysosomal thiol reductase which at low pH is capable of decreasing protein’s disulfide bonds. IFI30 is expressed constitutively in antigen-presenting cells and induced by gamma-IFN in other cell types. Also, IFI30 plays an important role in MHC class II-restricted antigen processing. IFI30 facilitates the generation of MHC class II-restricted epitopes from disulfide bond-containing antigen by the endocytic reduction of disulfide bonds and Also facilitates MHC class I-restricted recognition of exogenous antigens containing disulfide bonds by CD8+ T-cells or cross-presentation.

ReoVirus belongs to the RNA virus family of Reoviridae. The virions of reoviruses lack an outer envelope and show spheroidal. They measure approximately 70 nanometres and have two icosahedral capsids. Reoviruses enclose a core of segmented, double-stranded RNA virus and are a non-pathogenic naturally occurring virus. Approximately 100% of the population demonstrate signs of a previous reovirus infection, normally confined to the gastrointestinal or respiratory systems in the body. Reovirus particularly targets cells with a highly activated Ras signaling pathway and hence is a potent cancer killer.

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period. Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry of the target cell, the viral RNA genomeis converted to double-stranded DNAby a virally encoded reverse transcriptasethat is present in the virus particle. This viral DNA is then integrated into the cellular DNA by a virally encoded integraseso that the genome can be transcribed. Once the virus has infected the cell, two pathways are possible: either the virus becomes latentand the infected cell continues to function, or the virus becomes active and replicates, and a large number of virus particles are liberated that can then infect other cells.

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period.HIV-1 gp41 Subtype-b reacts to HIV1 antibody from HIV infected patients, over 90% HIV1 samples collected in house were tested strongly positive by rapid test.

HIV-1 and HIV-2 appear to package their RNA differently. HIV-1 binds to any appropriate RNA whereas HIV-2 preferentially binds to mRNA which creates the Gag protein itself. This means that HIV-1 is better able to mutate. HIV-2 is transmitted in the same ways as HIV-1: Through exposure to bodily fluids such as blood, semen, tears and vaginal fluids. Immunodeficiency develops more slowly with HIV-2. HIV-2 is less infectious in the early stages of the virus than with HIV-1. The infectiousness of HIV-2 increases as the virus progresses. Major differences include reduced pathogenicity of HIV-2 relative to HIV-1, enhanced immune control of HIV-2 infection and often some degree of CD4-independence. Despite considerable sequence and phenotypic differences between HIV-1 and 2 envelopes, structurally they are quite similar. Both membrane-anchored proteins eventually form the 6-helix bundles from the N-terminal and C-terminal regions of the ectodomain, which is common to many viral and cellular fusion proteins and which seems to drive fusion.

HIV2 gp160 protein contains HIV2 Subtype A sequence, covering C4, V5, and C5 from HIV2 gp120 and extending to HIV2 gp36.

The B19 virus, usually referred to as parvovirus B19 or sometimes as erythrovirus B19, belongs to the family of parvoviruses, genus erythrovirus. B19 virus causes a childhood rash named “fifth disease” or “erythema infectiosum” which is ordinarily known as “slapped cheek syndrome”. Erythroviruses are members of the Parvoviridae family of small DNA viruses. The B19 virus is a non-enveloped, icosahedral virus which contains a single-stranded linear DNA genome. Parvovirus B19 is classified as erythrovirus because of its capability to invade red blood cell precursors in the bone marrow. This virus is mainly spread by infected respiratory droplets; though, blood-borne transmission has also been reported.

Adiponectin is an important negative regulator in hematopoiesis and immune systems. It may be involved in ending inflammatory responses through its inhibitory functions. Inhibits endothelial nf-kappa-b signaling through a camp-dependent pathway. Inhibits tnf-alpha- induced expression of endothelial adhesion molecules. Involved in the control of fat metabolism and insulin sensitivity.

E-selectin which is also called Endothelial leukocyte adhesion molecule 1, ELAM1, ELAM belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. Eselectin is expressed on the surface of endothelial cells and mediates the interaction of leukocytes and platelets with endothelial cells during an inflammatory response. E-selectin is present in single copy in the human genome and contains 14 exons spanning about 13 kb of DNA.

NFKB inhibitor interacting Ras-like 2 (NKIRAS2) is an inhibitor of the transcription factor NF-kappaB. NKIRAS2 is similar to the Ras-like small GTPases which associate with IkappaB. The Ras-like proteins- NKIRAS1 and NKIRAS2, interact with the PEST domains of I?B? and I?B? and reduce their rate of degradation. NKIRAS2 is an atypical Ras-like protein which functions as a potent regulator of NF-kappa-B activity by preventing the degradation of NF-kappa-B inhibitor beta (NFKBIB) by most signals, explaining why NFKBIB is more impervious to degradation.

IFNs are cytokines that are widely known to induce potent anti-viral activity. IFN-a exerts a variety of other biological effects, including antitumor and immunomodulatory activities and are increasingly used clinically to treat a range of malignancies, myelodysplasias and autoimmune diseases.

EIF1 is important for scanning and plays a role in initiation site selection. EIF1 promotes the assembly of 48S ribosomal at the authentic initiation codon of a conventional capped mRNA.

UBE2D3 enzymes are human homologs of the yeast UBC4/5 family and play many important regulatory roles in inflammation and cancer. UbcH5a mediates the degradation of a myriad of short-lived regulatory proteins (such as p53 in the presence of E6/E6-AP or MDM2, c-Fos, I?B?, p105) and abnormal proteins. UBE2D3 has 88% and 89% sequence identity with UbcH5a and UbcH5b respectively.

UbcH12 is functional in in vitro NEDDylation reactions. It has been shown to form a thioester linkage with NEDD8 in the presence of the NEDD8 activating enzyme complex Uba3/APP-BP1. APP-BP1 binds to the amyloid precursor protein (APP) carboxy terminal domain and is important in conjunction with Uba3 and UbcH12 in driving cells through the S to M checkpoint. It was demonstrated to be the E2 responsible for the NEDDylation of the Cul-1 component of the SCF (?-TRCP) complex which is important as the E3-ligase in the ubiquitinylation of I?B?. NEDDylation of Cul-1 is essential for conjugation and processing of NF-?B p105 by SCF (?-TRCP) following phosphorylation of the complex. A dominant negative form of UbcH12, previously demonstrated to sequester NEDD8 and inhibit its conjugation, inhibits both conjugation and processing of p105, which is alleviated by wild-type UbcH12.

CD21 is expressed strongly on mature B cells, follicular dentritic cells and weakly on immature thymocytes and T lymphocytes. In B-cell ontogeny, CD21 appears after the pre-B-stage, is maintained during peripheral B-cell development and is lost upon terminal differentiation into plasma cells. CD21 expression is also gradually lost after stimulation of B cells in vitro. CD21 functions as receptor for C3d, C3dg and iC3b Complement components, for EBV and for IFNalpha. CD21 binds to CD23 and associates with CD19, CD81 and Leu13 to form a large signal-transduction complex involved in B cell activation.