Cloning and Structure Prediction of C-Type Lectin 19 (CTL-19) from Silkworm (Bombyx mori L.)

Abstract

Bombyx mori L. is a highly significant insect due to its silk production affects several industries. Unfortunately, B. mori farming has recently experienced mortality issues caused by pathogenic infectious diseases. Despite the extensive study of innate immunity of B. mori, information regarding the molecular functions and mode of actions of C-type lectin 19 (CTL-19) in the innate immunity of B. mori remains limited. Therefore, this study aimed to predict the structure of the B. mori CTL-19 also clone and produce the recombinant protein to better understand its role in the silkworm's innate immunity. The open reading frame (ORF) of the CTL-19 gene (945bp) was successfully amplified and cloned to pGEM®-T Easy Vector. The mature protein consists of 294 amino acids with 2 CRDs, 9 conserved cysteine, and two specific carbohydrate binding motifs. Protein threading demonstrated to be superior in order to predict the ligand binding site in comparison to homology modelling. The predicted molecular weight is 33.26 kDa, with pI value of 5.70. Furthermore, molecular docking analysis reveal that BmCTL-19 have ability to bind to various carbohydrate residues. The BmCTL-19 gene will be sub clone into an appropriate expression vector and produce purified recombinant protein to evaluate its properties.