Molecular Characterization, Recombinant Expression, and Functional Analysis of Carboxypeptidase B in .

The Pacific white shrimp () is economically significant, and its growth is regulated by multiple factors. Carboxypeptidase B (CPB) is related to protein digestion, but its gene sequence and features in are not fully understood. This study aimed to explore the molecular and functional properties of CPB in . The Lv-CPB gene was cloned, and bioinformatics analysis, qRT-PCR, in situ hybridization, recombinant protein expression in , and an enzyme activity assay were performed. The Lv-CPB gene is 1414 bp long with a 1263 bp ORF encoding a 420-amino-acid protein. It is stable, hydrophilic, and is highly expressed in the hepatopancreas. The recombinant protein was efficiently expressed with a molecular weight of about 47 kDa. The optimal pH and temperature for Lv-CPB were 8.0 and 50 °C, respectively. This study revealed the molecular and functional characteristics of Lv-CPB, providing insights into its role in shrimp digestion, as well as suggestions for improving aquaculture practices.