Molecular characterisation and in silico analysis of the gene encoding
14-3-3 tegumental protein of Schistosoma spindale
Abstract
Background Schistosoma spindale is a highly prevalent and
pathogenic snail borne trematode of ruminants in the Indian
subcontinent. The zoonotic significance of this parasite is associated
with cercarial dermatitis in man. Human schistosome infection is
infamous for its high morbidity and mortality rates and, animal
schistosomosis adversely affects the livestock sector in endemic areas.
Several protein candidates of schistosomes have been characterised to
exploit the diagnostic and vaccine potential for the control of
infection in man and animals, amongst which tegumental proteins have
been found quite promising. However, such proteins of Indian
schistsosome species have not been yet studied systematically.
Objectives In this study, molecular characterisation of 14-3-3
tegumental protein encoding gene of S. spindale and in
silico analysis of the predicted protein structure were done to assess
its immunogenicity. Methods Kerala isolates of adult S.
spindale worms were collected from mesentery samples, Total RNA was
isolated and cDNA was synthesised from it. The synthesised cDNA was used
as a template for the PCR amplification of the Ss14-3-3 gene and the
confirmed amplicons were then column purified and bidirectionally
sequenced using Sanger’s di-deoxynucleotide chain termination method.
The sequences obtained were merged and subjected to further analysis
using bioinformatic tools. Results A 759 bp amplicon of 14-3-3
tegumental protein encoding gene of S. spindale was translated
into a protein sequence having 252 amino acids. The Ss14-3-3 nucleotide
sequence showed the highest similarity of 94.99 per cent with S.
bovis 14-3-3 zeta isoform mRNA. However, Ss14-3-3 protein sequence had
the highest similarity with the 14-3-3 putative protein of S.
mansoni (99.21 per cent). With the help of bioinformatic tools, it was
concluded that the secondary and tertiary structures of this protein
were stable and three potential B cell epitopes exists within the
translated protein sequence. The protein was shown to possess structural
stability and immunogenicity which makes it a potential immunogenic
candidate against schistosomosis. Conclusions A 14-3-3 tegumental
protein encoding gene of S. spindale was characterized for the
first time. Sequence data was generated and in silico analysis
revealed structural stability and possible immunogenicity. The study
would serve as a platform to unravel the characteristics of tegumental
proteins of animal schistosomes to be used in diagnostics and vaccines.
However, further wet lab experiments including expression studies are
necessary to validate these findings.