Newly patented diagnostic tool for aquaculture pathogen to boost shrimp cultivation

Scientists have developed a handy diagnostic tool that detects an aquaculture pathogen known as the White Spot Syndrome Virus (WSSV). The peptide-based diagnostic tool by scientists of Agharkar Research Institute (ARI), an autonomous institute of the Department of Science and Technology (DST) has been grated patent on 31 March 2022 as an alternative biorecognition element.

Infection caused by the WSSV to the shrimp Penaeus vannamei results in huge loss of crop. This high value super-food is susceptible to a wide range of viral and bacterial pathogens and the probability of occurrence of infections is rather high.  Improved nutrition, probiotics, disease resistance, quality control of water, seed and feed, immuno-stimulants and affordable vaccines play an important role in enhancing the production. Technologies for early and rapid detection of pathogens on the field will help fish and shell-fish farming which provides significant export revenue to the country which is a leading supplier of shrimp to the USA.

To provide a handy, self-use diagnostic for WSSV, Dr Prabir Kulabhusan, Dr Jyutika Rajwade and Dr Kishore Paknikar developed a lateral flow assay using gold nanoparticles for easy visualization of the results. Instead of using poly-/mono-clonal antibodies in assay development, the ARI scientists selected twelve amino acid containing peptides from a phage display library by biopanning. This was a time- and cost-saving approach, eliminating the need for immunization of laboratory animals to obtain the antisera. With the use of peptides, cold-chain requirements for storage are reduced and the assay becomes production friendly.

“Our data indicates high specificity (100%) and sensitivity (96.77%) of the assay, early detection from hemolymph, highly reproducible results with a time-to-result of only 20 minutes,” said Dr Jyutika Rajwade.

The inventors have published this research in Applied Microbiology & Biotechnology and Journal of Molecular Modelling. ARI PhD student Ms Snehal Jamalpure-Lakka, has presented this idea at the National Bio-Entrepreneurship Conclave (NBEC)-2021 and awarded. She will take this work further for commercialization.

Publications

• PK Kulabhusan, JM Rajwade, ASS Hameed, KM Paknikar. 2017. Lateral flow assay for rapid detection of white spot syndrome virus (WSSV) using a phage-displayed peptide as bio-recognition probe. Applied Microbiology and Biotechnology. 101:4459–4469
• S Jamalpure, G Panditrao, PK Kulabhusan, AS Sahul Hameed, KM Paknikar, M Joshi, JM Rajwade. 2020. In silico studies on the interaction of phage displayed biorecognition element (TFQAFDLSPFPS) with the structural protein VP28 of White spot syndrome virus. Journal of Molecular Modelling. 26:264 10.1007/s00894-020-04524-z
• Immunoassay, peptide-based agent and field-usable kit for early rapid detection of white spot syndrome virus (Patent No. 393879)

Handy assay for detection of WSSV (High specificity for WSSV, other viruses not detected)	In-silico study of VP28 (major capsid protein of WSSV) binding to the 12-mer peptide (blue)

Patent

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