Screening and bioinformatic analysis of trehalase in Thelazia callipaeda / 中国血吸虫病防治杂志

Objective To characterize the trehalase gene in Thelazia callipaeda through screening the annotated data of the T. callipaeda genome, and to investigate the biological characteristics of the trehalase gene-coding protein. Methods The trehalase gene was screened from the T. callipaeda genome and subjected to validation by using a PCR assay. The structural features of the coding protein were analyzed with bioinformatics tools, including hydrophobicity, transmembrane region, signal peptides, conserved domains, as well as the secondary and tertiary structures and the antigen epitope. Homology analysis of the amino acid sequences was performed, and the phylogenetic tree was built by the MEGA X software. In addition, the protein-protein interaction network was deduced from the STRING database. Results The sequence of the trehalase gene with the complete CDS region was obtained from T. callipaeda genome, which had a length of 1 638 bp and encoded 545 amino acids. The encoded protein was predicted to have a molecular weight of 63 478.48 ku and be a secretory protein. The 5′ domain of the encoded protein contained a signal peptide without transmembrane regions, and was predicted to contain 7 antigen epitopes. Based on the protein-protein interaction network of nematodes in the STRING database, the protein-protein interaction network of the trehalase gene of T. callipaeda was deduced, and 27 interactions covering 10 genes were identified. Conclusions A trehalase gene is successfully identified in T. callipaeda genome and its coding protein receives a bioinformatics analysis, which provides insights into the research on the biological functions of the protein and the screening of vaccine candidates for thelaziasis callipaeda.

A new cadalene sesquiterpene glycoside from Dendrobium nobile / 药学学报

Using column chromatographic and preparative HPLC technologies, we isolated a new sesquiterpene glycoside from the stem of Dendrobium nobile. With spectroscopic techniques including NMR and MS, the new compound was identified as cadalene-12-O-β-D-glucopyranoside. This type of compound was dehydrogenated from cadinane sesquiterpene to achieve a naphthalene ring, and it is rare from a natural resource.