Unravelling the genomic origins of lumpy skin disease virus in recent outbreaks.

Lumpy skin disease virus (LSDV) belongs to the genus Capripoxvirus and family Poxviridae. LSDV was endemic in most of Africa, the Middle East and Turkey, but since 2015, several outbreaks have been reported in other countries. In this study, we used whole genome sequencing approach to investigate the origin of the outbreak and understand the genomic landscape of the virus. Our study showed that the LSDV strain of 2022 outbreak exhibited many genetic variations compared to the Reference Neethling strain sequence and the previous field strains. A total of 1819 variations were found in 22 genome sequences, which includes 399 extragenic mutations, 153 insertion frameshift mutations, 234 deletion frameshift mutations, 271 Single nucleotide polymorphisms (SNPs) and 762 silent SNPs. Thirty-eight genes have more than 2 variations per gene, and these genes belong to viral-core proteins, viral binding proteins, replication, and RNA polymerase proteins. We highlight the importance of several SNPs in various genes, which may play an essential role in the pathogenesis of LSDV. Phylogenetic analysis performed on all whole genome sequences of LSDV showed two types of variants in India. One group of the variant with fewer mutations was found to lie closer to the LSDV 2019 strain from Ranchi while the other group clustered with previous Russian outbreaks from 2015. Our study highlights the importance of genomic characterization of viral outbreaks to not only monitor the frequency of mutations but also address its role in pathogenesis of LSDV as the outbreak continues.

Molecular phylogeny of Capripoxviruses based on major immunodominant protein (P32) reveals circulation of host specific sheeppox and goatpox viruses in small ruminants of India.

Sheeppox and goatpox are highly contagious viral diseases of small ruminants causing severe economic losses to the livestock farmers. The disease is enzootic in Asia including India, Middle East and African countries. In the present study, a total of 28 isolates from twenty five sheeppox and goatpox disease outbreaks were phylogenetically analyzed based on P32 gene/protein along with homology modeling and docking using heparan sulfate and UDP-glucose. Three distinct lineage-specific clusters as per their host origin were recorded. Multiple sequence analysis of P32 gene revealed that genetically similar sheeppox virus (SPPV) and goatpox virus (GTPV) strains are circulating in India. Phylogenetically, Lumpy skin disease (LSDV) and SPPV had a closer genetic relationship than GTPV. Comparative sequence alignment indicated conservation of various motifs such as glycosaminoglycan (GAG), chemokine like motif (CX3C) and Asp-Glu-any other residue-Asp (D/ExD), as well as viral specific signature residues in SPPV and GTPV isolates. Structurally, P32 protein of SPPV and GTPV with mixed α helices and ß sheets resembled with crystal structure of homologue vaccinia virus H3L protein. Docking studies in P32 protein of SPPV and GTPV revealed conserved binding pattern with heparan sulfate which is involved in the virus attachment and varied glycosyltransferase fold with UDP-glucose. These findings may help in development of suitable vaccines/diagnostics and therapeutics against capripoxviruses.

Molecular characterization of sheeppox virus from outbreaks in Karnataka, India.

AIM: This study aimed to characterize sheeppox virus (SPPV) using the P32 gene of the Capripoxvirus (CaPVs). MATERIALS AND METHODS: Clinical samples of skin, scabs, and nasal swab from suspected outbreaks Horalagallu (n=13) and Gerahalli (n=11) at Ramanagara district in Karnataka were collected. All the samples were initially subjected to genus-specific diagnostic polymerase chain reaction (PCR). The pooled clinical samples from each outbreak were also subjected to virus isolation. The isolates were confirmed by CaPVs genotyping PCR targeting the full-length P32 gene, followed by sequencing and phylogenetic analysis. RESULTS: The clinical signs and lesions varied from mild to severe degree with no specificity between age and sex. Specific cytopathic changes in cell morphology were observed in infected Vero cells from both outbreaks, which were confirmed by PCR. The complete P32 gene from two outbreaks was successfully amplified with the expected amplicon size of 1006bp. The sequencing and phylogenetic analysis revealed that both the outbreaks were due to SPPV and shared high similarity with published SPPVs from Karnataka and other parts of India. CONCLUSION: The current study showed that complete P32 gene-based genotypic PCR assay can be used for genetic characterization and molecular epidemiology of both sheeppox and goatpox diseases and also to differentiate the causative agents. The sequence analysis revealed 100% similarity among the two outbreak isolates suggesting the same strain of the virus and common source of infection for the outbreaks.

Protective effect of partially purified 35 kDa protein from silk worm (Bombyx mori) fecal matter against carbon tetrachloride induced hepatotoxicity and in vitro anti-viral properties.

CONTEXT: It has been found that many proteins from silkworm (Bombyx mori L.) fecal matter have been active against human immunodeficiency virus, Sendai virus, herpes simplex virus type-1, and nuclear polyhedrosis virus. OBJECTIVE: A partially purified 35 kDa protein from silkworm was screened for its hepatoprotective activity, and in vitro antioxidant, and antiviral properties against camelpox and goatpox viruses. MATERIALS AND METHODS: The study investigated the efficiency of the partially purified 35 kDa protein from silk worm fecal matter against CCl4-induced liver damage measured in terms of enzyme levels such as aspartate aminotransferase (AST), alanine amino transferase(ALT), alkaline phosphatase (ALP) and total bilirubin, which maintain liver integrity. In vitro antioxidant potential of this protein was determined based on its ability to scavenge 2, 2-diphenylpicrylhydrazyl (DPPH) and superoxide anions scavenging activity. Further, in vitro cytotoxic effect on Vero cells and antiviral activity against goatpox and camelpox viruses were also studied. RESULTS: The protein had significant hepatoprotection against CCl4-induced liver damage and scavenging of DPPH radical and superoxide anion activity. However, the protein did not inhibit the multiplication of either virus tested at its maximum non-toxic concentration (MNTC) in vitro. DISCUSSION AND CONCLUSION: The partially purified 35 kDa protein from silk worm Bombyx mori L fecal matter possessed protective effect against CCl4-induced oxidative stress in rat model. The protein was found to be ineffective against camelpox and goatpox viruses at its MNTC in vitro.