*1.7.3 Envelope or full length glycoprotein of EBOV*

It is generated on the surface of mature infectious virions and formed when RNA is edited by the process of transcription. The GP protein has 676 amino acids and is a structural polypeptide chain. It is encoded in two frames and functions in attachment and entry of virus into the defenseless cells of the host [48]. The GP is sub-divided into two glycoproteins; GP1 and GP2. They are membrane associated proteins and are linked with each other through disulfide bonding as shown in **Figure 6**. The GP1 is 130 kDa and GP2 is 24 kDa in size [47]. The GP1 helps in attachment to the receptors which are present on target cells [54]. The interactions allow the binding of viral particles to the dendritic cells and thus facilitates virus into cell entry [48]. GP2 is known as a class I viral fusion protein. Some characteristics of GP2 subunit protein of EBOV are as follows: towards the C-termini is the transmembrane helix while the "fusion- peptide" is found at the N-terminus [55]. The formation of this structure drives to combine the cell membranes of target cells and EBOV. It also helps the particles to enter into the cytoplasm of a healthy cell. The penetration of virus is mediated by the fusion of the membranes of endosomes with the endocytosed virus particle [56].

Survey of the literature showed that currently there are no crystal structures of both secreted and envelope glycoproteins available which are important for designing novel drugs that can inhibit the attachment of these glycoprotein to the host cells receptors and also to halt the activity of the secretary and soluble glycoproteins. In one of our study, we have constructed 3D structures through homology modeling [57]. The molecular dynamics simulation study of the obtained homology models and several drug docking results showed that these proteins can be targeted with small

**Figure 5.**

*EBOV soluble glycoprotein (sGP) involved in host neutrophil neutralization and immune system evasion.*

**59**

*Ebola, the Negative Stranded RNA Virus DOI: http://dx.doi.org/10.5772/intechopen.91776*

**Figure 6.**

*EBOV envelope glycoprotein.*

ligand molecules [57]. Further computation studies and experimental work will prove the usefulness of these small molecules as inhibitor of the EBOV important proteins [57]. The current advancement in cryo-electron microscopy should be utilized for the elucidation of EBOV structure like that of influenza, dengue, Zika and other arboviral diseases [57–60]. The availability of protein structure will help in molecular dynamics simulation and docking of these important viral proteins with suitable ligands and it

A number of researchers have developed vaccines in their laboratories which are in initial stages and have some minor side effects [61]. A recent investigation showed the development of a vaccine when the EBOV glycoproteins like GP and VP40 were injected in the guinea pigs and a protective immune response was observed [62]. The constructed vaccine recovers the infected rhesus macaque in a single dose [62]. Similarly the glycoproteins along with the matrix proteins VP24 and VP40 and in their absence were also tested in guinea pigs [63]. The antibodies produced against these antigens completely cure the tested subjects from EBOV [63]. Several other vaccine of EBOV was developed recently and they showed promising results in murine models with high success rate [64]. Thus, a success in the development of vaccine has been achieved but passing the clinical trials and its

A number of steps can be taken for the control and prevention of EBOV breakout and its spread. It is always better to avoid traveling to areas of EBOV outbreak and strict quarantine should be imposed on the people of that particular towns. Only medical teams with proper safety masks, cloths should be allowed for the care of patients infected with EBOV [65]. The damaged fruits and vegetables eaten by bat should not be consumed. Bats, monkeys, pangolins, and other wild animals' meat and their utilization in food, medicine, and soaps should be avoided [66]. Contacting these animals should be discouraged. Proper washing of hands and use of sanitizers should be encouraged in schools, airports, shopping malls, trains, and all public areas. It is always necessary for hospitals and health working organizations to share and spread information related to viral diseases outbreak to the general public on time and awareness campaigns should be launched at regular intervals of time. The advancement in cryo-electron microscopy should be utilized for structural resolution of the important enzymes of the EBOV and other fatal viruses so that novel drugs can be synthesized for their inhibition and control [67].

will enhance the exploration of novel antiviral drugs [59, 60].

**1.8 Progress in vaccines development for EBOV**

availability in the market will take time.

*1.8.1 Prevention and control*

**Figure 6.** *EBOV envelope glycoprotein.*

*Some RNA Viruses*

the small secretary glycoprotein neutralizes the host cell neutrophils through CD16b and resulting in lymphocyte death and further vascular dysregulation [52].

The soluble glycoprotein (sGP) is a non-structural protein with a single frame and has total 364-372 residues. At the N-terminal, 295 residues which also include the signal sequence are similar with full length GP. It differs in the length of C-terminal sequences [46, 50]. The formation of sGP is from Precursor (pre-sGP). Unedited mRNA is frequently produced from infected cells which results in the formation of precursor (pre-sGP). Precursor (pre-sGP) is cleaved by the furin protein to produce sGP and delta peptide [46, 50]. The orientation of sGP is antiparallel and linked together by disulfide bonding. It possesses dimerization between amino and carboxy groups as shown in **Figure 5**. The sGP plays a role in the evasion of humoral immune response by absorbing elicited antibodies. It also predicted to be involved in interaction with neutrophils of the host cells and their neutralization [53].

It is generated on the surface of mature infectious virions and formed when RNA is edited by the process of transcription. The GP protein has 676 amino acids and is a structural polypeptide chain. It is encoded in two frames and functions in attachment and entry of virus into the defenseless cells of the host [48]. The GP is sub-divided into two glycoproteins; GP1 and GP2. They are membrane associated proteins and are linked with each other through disulfide bonding as shown in **Figure 6**. The GP1 is 130 kDa and GP2 is 24 kDa in size [47]. The GP1 helps in attachment to the receptors which are present on target cells [54]. The interactions allow the binding of viral particles to the dendritic cells and thus facilitates virus into cell entry [48]. GP2 is known as a class I viral fusion protein. Some characteristics of GP2 subunit protein of EBOV are as follows: towards the C-termini is the transmembrane helix while the "fusion- peptide" is found at the N-terminus [55]. The formation of this structure drives to combine the cell membranes of target cells and EBOV. It also helps the particles to enter into the cytoplasm of a healthy cell. The penetration of virus is mediated by the fusion of the membranes of endosomes

Survey of the literature showed that currently there are no crystal structures of both secreted and envelope glycoproteins available which are important for designing novel drugs that can inhibit the attachment of these glycoprotein to the host cells receptors and also to halt the activity of the secretary and soluble glycoproteins. In one of our study, we have constructed 3D structures through homology modeling [57]. The molecular dynamics simulation study of the obtained homology models and several drug docking results showed that these proteins can be targeted with small

*EBOV soluble glycoprotein (sGP) involved in host neutrophil neutralization and immune system evasion.*

*1.7.2 Secreted or soluble glycoprotein and delta peptide of EBOV*

*1.7.3 Envelope or full length glycoprotein of EBOV*

with the endocytosed virus particle [56].

**58**

**Figure 5.**

ligand molecules [57]. Further computation studies and experimental work will prove the usefulness of these small molecules as inhibitor of the EBOV important proteins [57]. The current advancement in cryo-electron microscopy should be utilized for the elucidation of EBOV structure like that of influenza, dengue, Zika and other arboviral diseases [57–60]. The availability of protein structure will help in molecular dynamics simulation and docking of these important viral proteins with suitable ligands and it will enhance the exploration of novel antiviral drugs [59, 60].

#### **1.8 Progress in vaccines development for EBOV**

A number of researchers have developed vaccines in their laboratories which are in initial stages and have some minor side effects [61]. A recent investigation showed the development of a vaccine when the EBOV glycoproteins like GP and VP40 were injected in the guinea pigs and a protective immune response was observed [62]. The constructed vaccine recovers the infected rhesus macaque in a single dose [62]. Similarly the glycoproteins along with the matrix proteins VP24 and VP40 and in their absence were also tested in guinea pigs [63]. The antibodies produced against these antigens completely cure the tested subjects from EBOV [63]. Several other vaccine of EBOV was developed recently and they showed promising results in murine models with high success rate [64]. Thus, a success in the development of vaccine has been achieved but passing the clinical trials and its availability in the market will take time.

#### *1.8.1 Prevention and control*

A number of steps can be taken for the control and prevention of EBOV breakout and its spread. It is always better to avoid traveling to areas of EBOV outbreak and strict quarantine should be imposed on the people of that particular towns. Only medical teams with proper safety masks, cloths should be allowed for the care of patients infected with EBOV [65]. The damaged fruits and vegetables eaten by bat should not be consumed. Bats, monkeys, pangolins, and other wild animals' meat and their utilization in food, medicine, and soaps should be avoided [66]. Contacting these animals should be discouraged. Proper washing of hands and use of sanitizers should be encouraged in schools, airports, shopping malls, trains, and all public areas. It is always necessary for hospitals and health working organizations to share and spread information related to viral diseases outbreak to the general public on time and awareness campaigns should be launched at regular intervals of time. The advancement in cryo-electron microscopy should be utilized for structural resolution of the important enzymes of the EBOV and other fatal viruses so that novel drugs can be synthesized for their inhibition and control [67].
