Search results

Uridine phosphorylase from Salmonella typhimurium (StUP) catalyzes the reversible phosphorolysis of uridine with the formation of ribose-1-phosphate and uracil.

Chemokine (C-C motif) ligand 2 (CCL2) is a small cytokine belonging to the CC chemokine family that is also known as monocyte chemotactic protein-1 (MCP-1). It is found at the site of tooth eruption and bone degradation. In the bone, CCL2 is expressed by mature osteoclasts and osteoblasts and is under the control of nuclear factor ?B (NF?B).CCL2 recruits immune cells, such as monocytes, to sites of tissue injury and infection.This chemokine is produced as a protein precursor containing signal peptide of 23 amino acids and a mature peptide of 76 amino acids. It is a monomeric polypeptide, with a molecular weight of approximately 13kDa. As with many other CC chemokines, CCL2 is located on chromosome 17 in humans.The cell surface receptors that bind CCL2 are CCR2 and CCR5

The SARS CoV-2 3CL protease (C30 Endopeptidase) derived from human SARS-CoV-2 is a C30-type cysteine protease situated in the NS3 segment. SARS CoV-2 3CL protease biological functionality is needed to process viral polyproteins to functional complete units. SARS CoV-2 3CL protease (main protease) is the core protease protein in CoV and corresponds to non-structural protein 5. SARS CoV-2 3CL cleaves the CoV polyprotein at 11 locations. SARS CoV-2 3CL protease has a cysteine-histidine catalytic dyad at its active site and cleaves a Gln–(Ser/Ala/Gly) peptide bond. SARS CoV-2 3CL protease at position P1 cleaves the bond between the glutamine and serine/alanine/glycine. SARS CoV-2 3CL protease is necessary in the processing of the CoV replicase polyprotein.

The SARS Nucleocaspid is a protein that has a crucial structural importance, by making the virions associates with the RNA genome and therefore create a nucleocapsid that has the specific helical form. There has been found 3 different domain structures to the nucleocapsid antigen. This protein contains 3 outer structural proteins, the membrane (M), envelope (E), and spike (S) proteins.

CD55 belongs to the RCA (regulators of complement activation) family characterized by 4-30 SCRs (short consensus repeats) in their plasma-exposed regions. CD55 is widely expressed in malignant tumors and nevertheless functions as an inhibitor of the complement system.

African swine fever virus (ASFV) causes African swine fever (ASF), a disease of swine characterized by high morbidity and mortality. ASFV is a large DNA virus which belongs to Asfarviridae family. ASFV’s multilayered virion consists from up to 54 polypeptides while p72 is the major capsid component. Middle part of p72 protein contains most epitopes tested by monoclonal antibodies, while C-terminal peptide of P72 isused for the genotyping of ASFV isolates.

C1q is the first component of the classical pathway of complement activation. C1q along with the enzymatically active components C1r and C1s forms the C1 complex. When C1 binds to immunoglobulins in the form of immune complexes, it leads to activation of C1r and C1s proteases and a further activates the classical pathway of complement. C1q is a glycoprotein that belongs to the collectin family, having a molecular weight of about 410-462 kDa. C1q is a hexamer composed of globular heads attached to collagen-like triple-helix tails. The globular heads of C1q exclusively bind to the CH2 domain of IgG molecules or the CH3 domain of IgM. Each heavy chain of the immunoglobulin molecule contains a single binding site for C1q. Given that C1q must bind to no less than two heavy chains in order to alter its conformation and activate C1r and C1s, its activation follows only after binding to immunoglobulins in the form of immune complexes bound to multivalent antigens. C1q’s main physiological role is in the clearance of immune complexes and apoptotic bodies from the organism. Interruption of this process may lead to development of autoimmunity. Individuals with genetic deficiencies of C1q or other components of the classical pathway are at risk to develop SLE. C1q specifically binds to apoptotic bodies of human keratinocytes, vascular endothelial cells and lymphocytes. Complement components C1q and bound C3 mediate the clearance of apoptotic bodies. Hence, C1q may advance the clearance of autoantigens, avoiding stimulation of the immune system. Nonetheless, an extended exposition of the immune system to the neoepitope exposed on C1q molecules bound to immune complexes or apoptotic bodies could ultimately lead to an autoimmune response against C1q itself and to an altered complement function. C1q deficiency may also lead to disruption of the negative selection of autoreactive B cells. C1q along with other specific recognition proteins bind to the highly conserved lupus antigens (dsDNA and nuclear proteins) and activate the complement system. Autoantibodies against C1q (anti-C1q) are found in a number of autoimmune and infectious diseases like glomerulonephritis (GN) and lupus erythematosus (SLE), these antibodies are significant in clinical practice due to their negative predictive value.

ICAM-1 also called CD54 is a single chain membrane glycoprotein expressed on the surface of a variety of non-haematopoietic and haematopoietic cell types and has roles in signal transduction, cell signaling and lymphocyte adhesion. ICAM1 binds to integrins such as CD11a / CD18, or CD11b / CD18. ICAM1 is also used by Rhinovirus as a receptor. ICAM-1 is an intercellular adhesion molecule constantly present in low concentrations in the membranes of leukocytes and endothelial cells. When stimulated by cytokine the concentrations significantly increase. ICAM-1 can be stimulated by interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFA) and is expressed by the vascular endothelium, macrophages and lymphocytes. ICAM-1 is a ligand for LFA-1 which is a receptor found on leukocytes. Upon activation, leukocytes bind to endothelial cells via ICAM-1/LFA-1 and then transmigrate into tissues.
ICAM-1 is implicated in subarachnoid hemorrhage (SAH). Levels of ICAM-1 are shown to be notably elevated in patients with SAH.
Soluble ICAM-1 is detectable in the plasma and is elevated in patients with various inflammatory conditions.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

Chlamydia pneumoniae, a human pathogen causing respiratory infections and most likely contributing to the development of atherosclerosis and heart disease, is an obligate intracellular parasite which for replication needs to productively interact with and enter human cells. A specific region of a major outer membrane protein (MOMP), C. pneumonia is only recognized by C. pneumonia positive sera, and is used as an antigen for detection of IgG and IgM to Chlamydia pneumonia.

Chlamydia is a common term for infection with any bacterium belonging to the phylum Chlamydiae. This term derives from the name of the bacterial genus Chlamydiain the family Chlamydiaceae, order Chlamydiales, class and phylum Chlamydiae. There are two genera in Chlamydiaceae: Chlamydia and Chlamydophila. The genus Chlamydia includes three species: C. trachomatis, C. muridarum, and C. suis.

Human coronavirus NL63 also known as HCoV-NL63 is a type of coronavirus that was identified in 2004. Among the associated diseases are mild to moderate upper respiratory tract infections, bronchiolitis, severe lower respiratory tract infection and croup. Coronavirus NL63 appears mainly in young children, the elderly and immunocompromised patients with acute respiratory illness. Coronavirus NL63 has a seasonal association in temperate climates. Coronavirus NL63 is not an emerging virus, but rather one that continually circulates the human population. Transmission of HCoV-NL63 is likely through droplet expulsion from the respiratory tract, which may be cottages when close personal contact occurs. Coronavirus NL63 is able to endure for up to7 days in respiratory secretions and remains infective at room temperature. Once the virus has entered the host it binds to cellular receptors using spike proteins, similar to those found in HIV-1. Coronavirus NL63 is able to use Angiotensin-converting enzyme 2 (ACE2) as an entry receptor to target cells. Since coronavirus NL63 is a positive single-stranded RNA virus, the processes of replication via transcription and translation can be carried out in the cytoplasm of the infected cell.

Alpha 1 ACT is an early-stage acute-phase plasma protein and a serpin that preferentially inactivates chymotrypsin, cathepsin G, and chymase. Alpha-1- ACT, a serine protease inhibitor, is tightly associated with amyloid plaques in Alzheimer's disease (AD) and in normal aged human and monkey brain.
Regulation of the serine proteases and serine protease inhibitors plays an important role in neuromuscular differentiation. Prostate specific antigen (PSA), a chymotrypsin-like serine protease, is predominantly complexed to Alpha-1-ACT.

A human infecting coronavirus (viral pneumonia) called 2019 novel coronavirus, 2019-nCoV was found in the fish market at the city of Wuhan, Hubei province of China on December 2019.

The 2019-nCoV shares an 87% identity to the 2 bat-derived severe acute respiratory syndrome 2018 SARS-CoV-2 located in Zhoushan of eastern China. 2019-nCoV has an analogous receptor-BD-structure to that of 2018 SARS-CoV, even though there is a.a. diversity so thus the 2019-nCoV might bind to ACE2 receptor protein (angiotensin-converting enzyme 2) in humans.

While bats are possibly the host of 2019-nCoV, researchers suspect that animal from the ocean sold at the seafood market was an intermediate host. RSCU analysis proposes that the 2019-nCoV is a recombinant within the viral spike glycoprotein between the bat coronavirus and an unknown coronavirus.

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.

Chemokine (C-C motif) ligand 11 (CCL11) is a small cytokine belonging to the CC chemokine family that is also known as eotaxin. CCL11 selectively recruits eosinophils by inducing their chemotaxis, and therefore, is implicated in allergic responses. The effects of CCL11 are mediated by its binding to a G-protein-linked receptor known as a chemokine receptor. Chemokine receptors for which CCL11 is a ligand include CCR2, CCR3 and CCR5. The gene for human CCL11 (scya11) is encoded on three exons and is located on chromosome 17.

Zika virus (ZIKV) belongs to the family Flaviviridae and the genus Flavivirus, it is transmitted by daytime-active Aedes mosquitoes, such as A. aegypti and A. albopictus. The Zika virus is related to the dengue, yellow fever, Japanese encephalitis, and West Nile viruses. Much like the other flaviviruses, Zika virus is enveloped and icosahedral and has a nonsegmented, single-stranded, positive-sense RNA genome. Zika fever is an infection, which often causes no symptoms or only mild ones, like a mild form of dengue fever, and it is treated by rest. As of February 2016, there has been mounting evidence that Zika fever in pregnant women can cause abnormal brain development in their fetuses by mother-to-child transmission, which may result in miscarriage or microcephaly, however it is not yet known whether Zika virus causes microcephaly. Furthermore, a connection has been established with neurologic conditions in infected adults, including Guillain–Barre syndrome.

Complement Component C5a (C5a) is involved in the complement system and it is encoded by the C5 gene in human. Complement C5 is cleaved into C5a and C5b. C5a has an imperative role in chemotaxis and C5b forms the 1st part of the complement membrane attack complex. Complement C5 is the 5th component of complement, which plays a central role in inflammatory and cell killing processes. C5a protein is composed of alpha and beta polypeptide chains, which are linked by a disulfide bridge. An activation peptide, C5a, which is an anaphylatoxin, which has potent spasmogenic and chemotactic activity, is derivative from the alpha polypeptide via cleavage with a convertase. The C5b macromolecular cleavage product forms a complex with the C6 complement component, and this complex is the basis for creation of the membrane attack complex, which includes supplementary complement components.

Human T-lymphotropic virus (HTLV) is a human, single-stranded RNA retrovirus that causes T-cell leukemia and T-cell lymphoma. The virus activates a subset of T-helper cellscalled Th1cells. The result is a proliferation of Th1 cells and overproduction of Th1 related cytokines (mainly IFN-gamma and TNF-alpha). Feedback mechanisms of these cytokines cause a suppression of the Th2 lymphocytes and a reduction of Th2 cytokine production (mainly IL-4, IL-5, IL-10 and IL-13). The end result is a reduction in the ability of the infected host to mount an adequate immune response to invading organisms that require a predominantly Th2 dependant response (these include parasitic infections and production of mucosal and humoral antibodies).

Chlamydia is a common term for infection with any bacterium belonging to the phylum Chlamydiae. This term derives from the name of the bacterial genus Chlamydiain the family Chlamydiaceae, order Chlamydiales, class and phylum Chlamydiae. There are two genera in Chlamydiaceae: Chlamydia and Chlamydophila. The genus Chlamydia includes three species: C. trachomatis, C. muridarum, and C. suis.

SERPINA1 is secreted and is a serine protease inhibitor which its targets include elastase, plasmin, collagenase, leucocytic proteases, trypsin, chymotrypsin, and plasminogen activator. Defects in SERPINA1 gene can cause emphysema or liver disease. SERPINA1 is an endogenous inhibitor of serine proteases and inhibits the catalytic domain of human recombinant matriptase in vitro. Rise in SERPINA1 occurs as an acute phase response to tissue necrosis and inflammation. mutations in SERPINA1 and SLC11A1 genes change the balance between elastase produced by leukocytes during phagocytosis.

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.

Trichomonas vaginalis, an anaerobic, flagellated protozoan parasite, is most dominant protozoan causing sexual transmitted disease. T. vaginalis induced vaginal tract infection occurs as multiple steps involving interactions between host macromolecules and protozoan virulent factor. Adhension protein P65 of T. vaginalis has a vital part in assisting the penetration into vaginal tract surface.

Plasmodium falciparum heat shock proteins (PfHSPs) contribute to immunopathological alterations in infected hosts PfHSP70s may have a significant function during parasite adaptation in its environments. They have also been a focus of considerable attention due to their immunodominant antigenic nature and their properties as mediators of protective immunity.