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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.

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.

Treponema pallidum is a gram-negative spirochaete bacterium and is considered to be metabolically crippled. There are at least four known subspecies: T. pallidum pallidum, T. pallidum pertenue, T. pallidum carateum and T. pallidum endemicum. The helical structure of T. pallidum pallidum allows it to move in a corkscrew motion through viscous mediums such as mucus. Treponema pallidum sub sp. pallidum has one of the smallest bacterial genomes at 1.14 million base pairs (Mb) and has limited metabolic capabilities, reflecting its adaptation through genome reduction to the rich environment of mammalian tissue.

GST family of enzymes comprises a long list of cytosolic, mitochondrial, and microsomal proteins that are 45-55 kDa (dimer form) size and are capable of multiple reactions with a multitude of substrates, both endogenous and xenobiotic. GST catalyses the conjugation of reduced glutathione meaning the sulfhydryl group, to electrophilic centers on a wide variety of substrates. This activity is useful in the detoxification of endogenous compounds such as peroxidised lipids, as well as the metabolism of xenobiotics. GST binds toxins and function as transport protein. Glutathione S-transferase is used to create the so-called 'GST gene fusion system'. The GST is used to purify and detect proteins of interest. In a GST gene fusion system, the GST sequence is incorporated into an expression vector alongside the gene sequence encoding the protein of interest. Induction of protein expression from the vector's multiple cloning sites results in expression of a fusion protein - the protein of interest fused to the GST protein. This GST-fusion protein can then be purified from cells via its high affinity for glutathione. Fusion proteins offer an important biological assay for direct protein-to-protein interactions. The GST tag has the size of 220 amino acids, which, compared to other tags like the myc- or the FLAG-tag, is quite big. It is fused to the N-terminus of a protein. However, many commercially-available sources of GST-tagged plasmids include a thrombin domain for cleavage of the GST tag during protein purification. A GST-tag is often used to separate and purify proteins that contain the GST-fusion. GST-fusion proteins can be produced in Escherichia coli, as recombinant proteins.

PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and accelerate the folding of proteins. Cyclophilin-A is a cyclosporin binding-protein and may play a role in cyclosporin A-mediated immunosuppression. Cyclophilin-A can also interact with several HIV proteins, including p55 gag, Vpr, and capsid protein, and has been shown to be necessary for the formation of infectious HIV virions. Multiple pseudogenes that map to different chromosomes have been reported.

Aminoacylase-1 is a cytosolic, homodimeric, zinc-binding enzyme that catalyzes the hydrolysis of acylated L-amino acids to L-amino acids and acyl group, and has been postulated to function in the catabolism and salvage of acylated amino acids. ACY1 has been assigned to chromosome 3p21.1, a region reduced to homozygosity in small-cell lung cancer (SCLC), and its expression has been reported to be reduced or undetectable in SCLC cell lines and tumors. The amino acid sequence of human aminoacylase-1 is highly homologous to the porcine counterpart, and ACY1 is the first member of a new family of zinc-binding enzymes.

AHSG (fetuin-A) which is a glycoprotein present in the serum, is synthesized by hepatocytes. AHSG is one of the fetuin class of plasma binding proteins. It is involved in a number of functions, such as endocytosis, brain development and the formation of bone tissue. It is usually present in the cortical plate of the immature cerebral cortex and bone marrow hemopoietic matrix, hence it has been postulated that it participates in the development of the tissues. Yet, its exact significance is still vague. AHSG promotes endocytosis, hold opsonic properties and influences the mineral phase of the bone. Affinity for calcium and barium ions has been shown.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Borrelia belongs to a genus of bacteria of the spirochete phylum. Borrelia causes borreliosis, which is a zoonotic, vector-borne disease transmitted mainly by ticks and some by lice, depending on the species. Of the 36 known species of Borrelia, 12 are distinguished to cause Lyme disease or borreliosis and are transmitted by ticks. The main Borrelia species causing Lyme disease are Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii. The Borrelia genus members have a linear chromosome which is about 900 kbp in length as well as an excess of both linear and circular plasmids in the 5-220 kbp size range. The plasmids are atypical, as compared to most bacterial plasmids, since they contain many paralogous sequences, a large number of pseudogenes and, in some cases, essential genes. Moreover, a number of the plasmids have features suggesting that they are prophages.

WHSC2 (NELF-A) is a protein factor required for DRB-sensitive transcription. WHSC2 is one of the 5 components of the multisubunit NELF complex which cooperates with DSIF to repress RNA polymerase II elongation. The Wolf-Hirschhorn syndrome is a multiple malformation syndrome characterized by mental and developmental defects resulting from a hemizygous deletion of the distal short arm of chromosome 4 (4p16.3).

ADH1C is a member of the zinc-containing alcohol dehydrogenase family which metabolizes a large assortment of substrates, such as ethanol, retinol, other aliphatic alcohols, hydroxysteroids, and lipid peroxidation products. ADH1 is a monomorphic and a key factor in fetal and infant livers, becoming less active in gestation and only weakly active during adulthood.

AHSG (fetuin-A) which is a glycoprotein present in the serum, is synthesized by hepatocytes. AHSG is one of the fetuin class of plasma binding proteins. It is involved in a number of functions, such as endocytosis, brain development and the formation of bone tissue. It is usually present in the cortical plate of the immature cerebral cortex and bone marrow hemopoietic matrix, hence it has been postulated that it participates in the development of the tissues. Yet, its exact significance is still vague. AHSG promotes endocytosis, hold opsonic properties and influences the mineral phase of the bone. Affinity for calcium and barium ions has been shown.

AK3L1 is an affiliate of the adenylate kinase family of enzymes. AK3L1 enzyme is restricted to the mitochondrial matrix. Adenylate kinases-3 regulates the adenine and guanine nucleotide compositions within a cell by means of catalyzing the reversible transfer of phosphate group among these nucleotides. 5 different isozymes of adenylate kinase have been identified in vertebrates. The enzyme expression of various adenylate kinase isozymes is growth regulated and tissue-specific.

AKR1C3 is part of the aldo/keto reductase superfamily, which has at least 40 identified proteins. AKR1C3 catalyzes the conversion of aldehydes and ketones to their corresponding alcohols by utilizing NADH and/or NADPH as cofactors. AKR1C3 displays overlapping but distinct substrate specificity. AKR1C3 catalyzes the reduction of prostaglandin (PG) D2, PGH2 and phenanthrenequinone (PQ), and the oxidation of 9alpha,11beta-PGF2 to PGD2. AKR1C3 is involved in the pathogenesis of allergic diseases such as asthma. AKR1C3 controls cell growth and/or differentiation. AKR1C3 takes part in adrenal testosterone production. AKR1C3 expression is affected by metabolic disease, and its levels are considerably reduced in response to diet-induced weight loss and correlate with leptin levels.

Major Histocompatibility Complex Class I C (HLA-C) belongs to the HLA class I heavy chain paralogues. The HLA-C (class I molecule) is a heterodimer comprised of a heavy chain and a light chain (beta-2 microglobulin). The heavy chain is anchored in the membrane. Class I molecules have a key role in the immune system by presenting peptides derived from endoplasmic reticulum lumen. Class I molecules are expressed in virtually all cells.

Aspartoacylase is a homodimer which catalyzes the deacetylation of N-acetylaspartic acid (NAA) (a protein whose hydrolysis is crucial to maintenance of intact white matter) to generate acetate and L-aspartate. Aspartoacylase (ASPA) is expressed in the liver, lung and kidney tissue, as well as in the skeletal muscle and in cerebral white matter. NAA is ample in the brain where hydrolysis by aspartoacylase is believed to aid maintain white matter. In other tissues ASPA functions as a scavenger of NAA from body fluids. ASPA gene mutations cause Canavan disease (CAND or spongy degeneration of the brain).

Zinc-alpha-2-glycoprotein (AZGP1) protein stimulates lipid degradation in adipocytes and causes the massive fat losses linked with various advanced cancers. AZGP1 may bind polyunsaturated fatty acids.

ENSA is an endogenous ligand for sulfonylurea receptor. ENSA reduces K(ATP) channel currents by inhibiting sulfonylurea from binding to the receptor and thus stimulates insulin secretion. Endosulfine Alpha is part of a conserved cAMP-regulated phosphoprotein (ARPP) family. Endosulfine Alpha is an endogenous ligand for the sulfonylurea receptor, ABCC8/SUR1. Endosulfine Alpha is an endogenous regulator of KATP channels. ENSA modulates insulin secretion through the interaction with KATP channel. ENSA is a candidate gene for type 2 diabetes. ENSA is expressed in a wide range of tissues including muscle, brain, and endocrine tissues.

BLVRB (EC 1.3.1.24) catalyzes electron transfer from reduced pyridine nucleotides to flavins as well as methylene blue, pyrroloquinoline quinone, riboflavin, or methemoglobin. BLVRB is involved in protecting cells from oxidative damage or in regulating iron metabolism. BLVRB converts biliverdin to bilirubin in the liver, converting a double-bond between the second and third pyrrole ring into a single-bond. BLVRB plays a role as in human erythrocytic heme catabolic pathway and most mammalian species. Biliverdin reductase is abundantly expressed in kidney, spleen, liver and brain as well as at lower levels in the thymus and minimal levels being detected in testis.

O-Sialoglycoprotein Endopeptidase, also known as OSGEP is a member of the KAE1 / TsaD family. OSGEP is essential for the formation of threonylcarbamoyl group on adenosine at position 37 (t6A37) in tRNAs which read codons beginning with adenine. OSGEP take a direct catalytic part in the above reaction, however other proteins of the complex are required to fulfill this activity.

Glutathione S-transferase or GST, stands for a large family of detoxification proteins and enzymes. Glutathione S-transferase catalyzes glutathione reaction and an acceptor molecule to create S-substituted glutathione (S stands for sulfur). By this reaction, a large variety of compounds, for example therapeutic drugs, carcinogens & oxidative stress products, transformed. Glutathione S-transferase acts as a transport protein by binding toxins and acts as a transport protein. At first, the protein was isolated from Schistosomajaponicum, nowadays it is isolated from E. coli bacteria.

AHA1 is a cochaperone that stimulates hsp90 ATPase activity. AHSA1 binds the middle domain of Hsp90 (amino acid 272-627) and functions as an ATPase-activating protein that competes with p23 and other co-chaperones for Hsp90 binding.
AHA1 affects a step in the endoplasmic reticulum to golgi trafficking.

DLAT gene encodes component E2 of the multi-enzyme pyruvate dehydrogenase complex (PDC). PDC is located in the inner mitochondrial membrane and catalyzes the conversion of pyruvate to acetyl coenzyme A. The protein product of this gene, dihydrolipoamide acetyltransferase, takes acetyl groups created by the oxidative decarboxylation of pyruvate and transfers them to coenzyme A. Dihydrolipoamide acetyltransferase is the antigen for antimitochondrial antibodies which are found in about 95% of patients with the autoimmune liver disease primary biliary cirrhosis (PBC). In patients who suffer from this illness, activated T lymphocytes attack and destroy epithelial cells in the bile duct where this protein is abnormally distributed and overexpressed. PBC ultimately leads to cirrhosis and liver failure. Mutations in DLAT are also a cause of pyruvate dehydrogenase E2 deficiency which causes primary lactic acidosis in infancy and early childhood.

OAZ1 is a member of the ODC antizyme family. OAZ1 is auto-regulated expressed by polyamine-enhanced translational frame shifting. OAZ1 negatively controls polyamine synthesis by increasing the negative feedback loop regulating ornithine decarboxylase (ODC) activity. The OAZ1 protein inhibits ornithine decarboxylase and speeds up its detraction.