title: Molecular Characterization and Antibacterial Activity Analysis of Two Novel Penaeidin Isoforms from Pacific White Shrimp, Litopenaeus vannamei.
abstract: Penaeidins were important immunity effector molecules, which played a crucial role in innate immunity system of penaeid shrimp. Here, we reported two penaeidin isoforms from Litopenaeus vannamei, which were named as Lva-PEN 2 and Lva-PEN 3 according to the respective structure features. The results of amino acid sequence multiple alignments showed that high similarities existed among these penaeidins. A signal peptide sequence and a cysteine-rich domain which contained six cysteine amino acid residues existed in each penaeidin at the same time. Besides, there was a proline-rich motif which was composed of eight proline residues existed in each penaeidin. After the expression profile analysis was studied, we found that both Lva-pen 2 and Lva-pen 3 transcripts were up-regulated at 48 h after bacteria challenge. Except for the antibacterial activity against Gram-positive bacteria like other penaeidins, these two penaeidins could strongly bind to bacteria and possessed antiproteinase activity. It was speculated that these two penaeidins could prevent bacteria pervasion through bacteria-binding activity and antiproteinase activity. Meantime, the proline-rich motif played a crucial role in these biological processes.
authors.affiliation: The Institute of Bioengineering and Technology, Inner Mongolia University of Science and Technology, Baotou, 014010, Inner Mongolia Autonomous Region, China. nmdzq1981@163.com.
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Du
authors.affiliation: The Institute of Bioengineering and Technology, Inner Mongolia University of Science and Technology, Baotou, 014010, Inner Mongolia Autonomous Region, China.
authors.forename: Yan-Hui
authors.initials: YH
authors.lastname: Jin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000276:immunology* / Q000382:microbiology; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D020033:Protein Isoforms / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D016415:Sequence Alignment
chemical_list: D010455:Peptides; D020033:Protein Isoforms; D011994:Recombinant Proteins; C109157:penaeidin 2; C109158:penaeidin 3
keywords: Antibacterial activity; Litopenaeus vannamei; Penaeidin isoforms; Proline-rich motif; Proteinase inhibitor activity